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Framed Door x Fully Stamped Door | When designing a new subsystem for a new vehicle platform, technical requirements, performance targets and cost implications drive the decision process towards which concept to be adopted. If this platform is planned for worldwide introduction, local requirements and capabilities have to be put into the business equation. Among the possible design options for a Side Door Subsystem, including basically Inset doors and Limo doors with their variations, the best for the market is selected on: Commonality requirements through the platform family; Technical implications of each design concept; Technical excellence to produce parts with the required quality/cost in the local market; Costs and timing associated with each design concept; Benchmarking. This composition of factors drove the decision to adopt different design options for South America and Europe on the recently launched small car platform. This paper demonstrates the rationale of this decision making process and the positive outcomes of it. |
Average Vehicle Dimensions for Use in Designing Docking Facilities for Motor Vehicles | This SAE Recommended Practice establishes limits for empty vehicle floor heights and provides limits of vehicle dimensions for use in designing docking facilities for motor vehicles. |
Leading Edge Requirements Engineering for the Automotive Industry - With the Use of JAMA | There have been many publications about requirements management, and still organizations are struggling to show 100% coverage and traceability in a lean way. It does not start with CMMI nor SPICE. It does not end with tools like DOORs, Polarion, Codebeamer or JAMA. It does depend on the right setup and how it feels in the everyday life of an engineer. This paper defines and explains what it takes to establish leading edge requirements engineering for the automotive industry. It describes how work day integration of requirements engineering and management can be achieved. The different roles in engineering are addressed with their unique needs to support them. One 120% RQM data model is shown and explained. The necessary rollout project is designed with activities to adapt a tool to existing processes and individual tools, explain, improve, transfer as well as train/coach the engineers. The impact of and resolution for existing bypasses is discussed as well as the necessary qualification of rollout coaches. Before going in bit and byte - let?셲 not forget to get Product Management on board. Usability is a key for product success, so why should it be different for the tool success. Here we show how a tool need to adapt, not just to the different engineering roles but also to the interfaces of management and the rest of the tool landscape. In efficiency in use of roots in hesitation and fear of the engineers. Simple concepts are explained to introduce a creative fail-forward culture around requirements engineering. Chicken-or-Egg discussions are bypassed with a creative distinction or requirements versus specification. The activities around requirements are explained in a complete requirements lifecycle model. Necessary design levels and all RQM items are shown in and exemplary tool setup in JAMA Connect. A test driven bottom up approach is added for special use-cases. Finally it is shown how we can reduce surprises ate product release significantly with 100% traceability and integrated change management. The difference of coverage and traceability if shown and explained and how to use it to lift the readers requirements management in the 21st century. As part of the outlook, the challenge of configuration management is addresses as a problem that today is still not sufficiently supported by most requirements management tools.. |
Experimental noise and vibration analysis in an aircraft simplified hydraulic systems | Due to the great use of airplanes for transportation, it was necessary some studies to improve it, one of the most difficult problems to solve, is the noise generated by the systems. In-flight sound pressure levels can sometimes be intense and cause fatigue to the cabin crew, communication failures and discomfort to the passengers. This is often caused by the turbulent boundary layer over the aircraft body, engine noise and vibration and internal aircraft systems. The aircraft hydraulic system is responsible for moving the rudder, aileron, brakes, main door, and other components, and consequently, the noise of this system became more noticeable. This system comprises a pump, generally, located at the back of the aircraft and pipes, which are fixed along the fuselage. The pipes are connected to the fuselage using rubber mounts. Analyzing experimental measurements is possible to identify that hydraulic system contribute to the in-flight sound pressure level in the aircraft cabin. However is the connection between pipe and fuselage the main problem. In this paper, will be demonstrated a simplified methodology to analyze these noise, generated by the hydraulic system, with results of sound pressure and vibration measured in an experimental device, operated under different conditions. |
Ultra-Thin, Energy-Efficient Photodetector Integrated with Gorilla Glass | Photodetectors ??also known as photosensors ??contribute to the convenience of modern life. They convert light energy into electrical signals to complete tasks such as opening automatic sliding doors and automatically adjusting a cellphone?셲 screen brightness in different lighting conditions. Researchers are advancing photodetectors??use by integrating the technology with durable Gorilla glass, the material used for smartphone screens that is manufactured by Corning Incorporated. |
Simulating the Static and Dynamic Response of an Automotive Weatherstrip Component | Understanding the resonant behavior of vehicle closures such as doors, hoods, trunks, and rear lift gates can be critical to achieve structure-borne noise, vibration, and harshness (NVH) performance requirements, particularly below 100Hz. Nearly all closure systems have elastomer weatherstrip components that create a viscoelastic boundary condition along a continuous line around its perimeter and is capable of influencing the resonant behavior of the closure system. This paper outlines an approach to simulate the static and dynamic characteristics of a closed-cell Ethylene Propylene Diene Monomer (EPDM) foam rubber weatherstrip component that is first subjected to a large-strain quasi-static preload with a small-strain sinusoidal dynamic load superimposed. An outline of a theoretical approach using ?쐏hi-functions??as developed by K.N. Morman Jr., and J.C. Nagtegaal [1] is introduced followed by a discussion of the material characterization that was done to construct a suitable elastomer material model for finite element analysis (FEA). Next, to validate the approach, the FEA and correlation of a simple extension specimen is presented followed by the analysis and correlation of a weatherstrip component with a complex cross sectional shape. It is observed that the static and/or dynamic response of the weatherstrip material and component can be dependent on several factors such as excitation frequency, large-strain preload, vibration amplitude, component geometry, and friction. Correlation between simulation and experimental results for dynamic stiffness and loss factor are in general agreement below 100Hz. |
Application of the Hybrid FE-SEA Method to Predict Sound Transmission Through Complex Sealing Systems | Currently, the use of numerical and analytical tools during a vehicle development is extensive in the automotive industry. This assures that the required performance levels can be achieved from the early stages of development. However, there are some aspects of the vibro-acoustic performance of a vehicle that are rarely assessed through numerical or analytical analysis. An example is the modeling of sound transmission through vehicle sealing systems. In this case, most of the investigations have been done experimentally, and the analytical models available are not sufficiently accurate. In this paper, the modeling of the sound transmission through a vehicle door seal is presented. The study is an extension of a previous work in which the applicability of the Hybrid FE-SEA method was demonstrated for predicting the TL of sealing elements. A numerical validation of simplified Hybrid FE-SEA model is performed, which is followed by the application of the method to the TL of a car door seal. A full non-linear deformation/contact analysis is used to estimate the deformed geometry of the door seal in real conditions. The geometry is then used in a vibro-acoustic analysis to predict the in-situ transmission loss of the seal using a local Hybrid FE-SEA model. The channel between the door and the car structure where the seal is located is also included in the analysis. Results for the transmission loss are compared with experimental data, showing a good correlation. |
A Computational Process for Early Stage Assessment of Automotive Buffeting and Wind Noise | A computational process for early stage vehicle shape assessment for automotive front window buffeting and greenhouse wind noise is presented. It is a challenging problem in an experimental process as the vehicle geometry is not always finalized. For example, the buffeting behavior typically worsens during the vehicle development process as the vehicle gets tighter, leading to expensive late counter measures. We present a solution using previously validated CFD/CAA software based on the Lattice Boltzmann Method (LBM). A CAD model with realistic automotive geometry was chosen to simultaneously study the potential of different side mirror geometries to influence the front window buffeting and greenhouse wind noise phenomena. A glass mounted mirror and a door mounted mirror were used for this comparative study. Interior noise is investigated for the two phenomena studied. The unsteady flow is visualized and changes in the buffeting and wind noise behavior are explored. |
Boundary Condition Effect on the Correlation of an Acoustic Finite Element Passenger Compartment Model | Three different acoustic finite element models of an automobile passenger compartment are developed and experimentally assessed. The three different models are a traditional model, an improved model, and an optimized model. The traditional model represents the passenger and trunk compartment cavities and the coupling between them through the rear seat cavity. The improved model includes traditional acoustic models of the passenger and trunk compartments, as well as equivalent-acoustic finite element models of the front and rear seats, parcel shelf, door volumes, instrument panel, and trunk wheel well volume. An optimized version of the improved acoustic model is developed by modifying the equivalent-acoustic properties. Modal analysis tests of a vehicle were conducted using loudspeaker excitation to identify the compartment cavity modes and sound pressure response to 500 Hz to assess the accuracy of the acoustic models. The optimized acoustic model is also coupled with a structural finite-element model of the trimmed body to evaluate the effect of body panel flexibility on the interior sound pressure response. The optimized acoustic model is found to exhibit the best correlation in terms of the predicted sound pressure FRF response at the passenger compartment interior locations and at the compartment boundary surfaces. |
Evaluation of the Aerodynamic and Aeroacoustic Response of a Vehicle to Transient Flow Conditions | A vehicle on the road encounters an unsteady flow due to turbulence in the natural wind, unsteady wakes of other vehicles and as a result of traversing through the stationary wakes of roadside obstacles. Unsteady effects occurring in the sideglass region of a vehicle are particularly relevant to wind noise. This is a region close to the driver and dominated by separated flow structures from the A-pillar and door mirrors, which are sensitive to unsteadiness in the onset flow. Since the sideglass region is of particular aeroacoustic importance, the paper seeks to determine what impact these unsteady effects have on the sources of aeroacoustic noise as measured inside the passenger compartment, in addition to the flow structures in this region. Data presented were obtained during on-road measurement campaigns using two instrumented vehicles, as well as from aeroacoustic wind tunnel tests. Conventional admittance functions relating oncoming flow yaw angle to cabin noise response are generally not suitable due to the non-linear steady state characteristics obtained in the wind tunnel, i.e. the cabin noise does not vary with yaw angle in a linear fashion under steady-state conditions. Therefore two alternative approaches were used based on instantaneous conditions to determine a quasi-steady predicted cabin noise time-history. These techniques demonstrated that the cabin noise response to oncoming flow unsteadiness remained generally quasi-steady up to fluctuation frequencies of approximately 2 to 5 Hz, where above this smaller flow scales have a progressively smaller impact on cabin noise fluctuations. Therefore, with a measurement of both the cabin noise in the steady environment of the wind tunnel and the unsteady onset flow conditions, the fluctuations (and thus the modulation) of the wind noise under these unsteady conditions is able to be predicted. |
Investigation of Squeak and Rattle Problems in Vehicle Components by Using Simulation & Doe Techniques | The automotive and related industries are concentrating their efforts on improving comfort by lowering engine, wind, and road noise and vibrations. However, as background noise levels decrease, the squeaks and rattles (S & R) generated by the vehicle's many components become more noticeable and distracting. As a result of the absence of a dominant noise source from a traditional petrol/diesel car, (S & R) noise becomes more dominant than other types of noise in electric vehicles. In this paper, we propose a novel simulation technique for developing a systematic approach to identifying and solving (S & R) problems in vehicle components/sub-assemblies during the primary stage of product development cycle, thus reducing the overall product development time. This paper will present a novel approach to comprehending various methods and Design of Experiments (DOE) techniques used to determine the root cause of (S&R) problems and to solve those using numerical methods. |
Axiomatic Design of the Check Link for an Automotive Side Closure System | In the automotive industry, a lot of attention has been paid to the effort required for opening/closing the doors, and for a good reason. The door closing and opening effort creates an impression in the customer?셲 mind about the engineering and quality of the vehicle even before he or she enters it. Although this seems trivial compared to the complexity of the rest of the automobile, effective engineering of the door opening/closing effort is challenging due to the interaction of several design parameters. Some of the best practices focus on satisfying targets for the energy required shutting the door from a small open position (around 10 degrees). However this practice ignores the complete closing/opening motion of the door from a full open position. In this paper Axiomatic Design principles were used to obtain a better understanding of the door opening/closing motion from a full open position, in terms of the functional requirements (FR), and how these requirements are satisfied by the various design parameters (DP) of the door closure system. In this paper we present an analysis of the opening/closing efforts of the side door closure system using this Axiomatic Design approach, and a discussion on the design of the check-link. The complete opening/closing motion is a result of the interaction of the different components of the door closing system, such as the latch, weather seal, energy loss due to air-binding effect, the inclination of the hinge axes, and the check-link. FR/DP decomposition of the Door System is presented. This provides the framework for creative design solutions. |
Development and Validation of Utility Matrix for Automotive Interiors in Real World Usage | As the real world usage profile of customers is becoming increasingly dynamic the need for more utility features in interior parts of vehicle has increased. The main purpose of the study is to analyze how the changing customer style actually influences the volume requirement of the utility spaces i.e. at the glove box, console door pocket etc. In the present study, an exhaustive list of utilities, and a utility matrix based on the user characteristics for automotive interiors is developed. Based on customer reviews on the web and expert opinions, seven user profiles were defined. The selection matrix is arrived at by using the usability index, accessibility index and the disbursement index. The matrix is evaluated using statistical methods and validated for real world usage. The selection matrix is used to identify relatively important utility features and preferred locations in automotive interior parts. |
Secondary Control Modifications | This SAE Recommended Practice establishes a uniform procedure for assuring the manufactured quality, installed utility and performance of automotive products to the relocation, alteration, replacement and/or extension of secondary controls and systems other than those provided by the vehicle manufacturer (OEM). These products are intended to provide driving capability to persons with physical disabilities. These products function as adaptive modifications to compensate for lost or reduced function in the extremities of the driver. These include, but are not limited to the following: Cruise Control; Door Locks; Gear Selector; Hazard Flasher; Headlight Beam Selector; Heater/Vent/Air Conditioner (HVAC); Horn; Ignition/Starter; Light controls; Mirrors; Parking Brake; Power Seats; Turn Signals; Power Window Controls; and Windshield Wiper/Washer and defogger; Rear Accessories (Defogger, Wiper/Washer). The purpose of any secondary control adaptation is to provide the effective use of the motor vehicle operating systems to a driver with a disability, so that he or she may drive and operate that motor vehicle with the same degree of safety as a non-disabled driver. Thus, the adaptive equipment must be (1) accessible to the driver with a disability for whom it is designed, (2) not susceptible to inadvertent operation which may be inconvenient or dangerous for the driver and other users of the roadway, and (3) suitable by non-disabled drivers who may have a need to operate the motor vehicle whenever possible. For purpose of this document, the secondary controls listed previously have been classified according to the following protocols. The categorization of these controls, while different from other SAE publications, is reflective of the manner in which driver rehabilitation specialists determine appropriate vehicle modifications. These categories are arranged to assign priorities that allow the user to operate a vehicle in the most efficient manner possible. Mode A - These controls shall be operable by the driver while the vehicle is in operating mode. They must be accessible to the driver for which they were intended while being able to maintain control of the vehicle steering, brake and accelerator functions. Included in this group are: Cruise control ?쏶et;??Headlight Beam Selector; Horn; Turn Signals; and, Windshield Washer/Momentary Wipe. Mode B - These controls shall be operable by the driver while maintaining control of the vehicle brake function with the vehicle not in motion, as in the case of vehicle start-up or re-start necessitated by engine stall. Included in this group are: Gear Selector and Ignition/Starter. Mode C - These controls shall be at least operable by the driver when the vehicle is stationary, either temporarily or parked. Included in this group are: Cruise control ?쏰n??and ?쏰ff;??Door Locks; Hazard Flashers; Heater/Vent/Air Conditioner (HVAC); Light Controls; Mirrors; Parking Brake; Power Seats; Windshield Wiper; and Power Window Controls; Rear Accessories (Defogger, Wiper/Washer). |
A Study on the Methodology for Improving IQS Score for Door Opening/Closing Effort | IQS score (hard to open/close) is a major factor in determining automotive door closing performance. There are several functions that automotive side doors must fulfill: isolation from snow/ rain/ noise/ dust/ high temperature, wind noise, and opening/closing functions. This paper focuses on side door Opening/Closing, which is not only the primary function but also the first operation that all customers experience when car shopping. As the subjective demands of customers have increased and their level of sophistication has grown, the ergonomics of automotive side door functions has become a critical issue for both designer and customer. The side door area does not generally have specifications because door operability totally relies on each customer's senses and there are no parameters to be measured by test/experimental devices. So the IQS score could become the standard for evaluating a door's difficulty of opening and closing. The objective of this work is 1)to develop a correlation between subjective evaluation, some test results and IQS score (hard to open/close) and 2)to find ways to improve IQS score (hard to open/close) by reducing the minimum closing velocity. |
Study of Minimum Door Closing Speed Analysis Method | The minimum door closing speed is an important target in vehicle door design. Engineers need a proper method to evaluate the door closing speed during the design phase. Analytical approaches are presented to solve the difficult issues in analyzing the minimum door closing speed. First, the weather strip is simplified into a discrete model with several spring elements. This method does not need to use 3-D contact analysis for the weather strip and can save computing time with acceptable accuracy. Second, the minimum closing speed is solved by using the energy equation which needs one iteration only. The method has high efficiency and can be used to evaluate the door closing speed effectively during the design phase. |
Door Check Load Durability - Fatigue Life Prediction | This paper describes an analytical methodology for predicting the fatigue life of a door system for check load durability cycles. A check stop load durability cycle occurs when a customer opens the door beyond the door detent position with a force applied on the check link or hinge check stops. This method combines Finite Element Analysis (FEA) model and fatigue code to compute the durability requirements. The FEA model consists of Door-in-White (DIW) on body with integrated hinge check link or independent check link. Nonlinear material, geometric and parts contact were considered for the door with body-in-white (BIW). Several door hinge designs, with integrated and independent check links, were investigated. Using the Von Mises stress and plastic strain from the above analysis, the fatigue life was predicted and compared with the test data. Integrating FEA and fatigue allows predicting the threshold total strain value, which is developed, for check load durability requirements. The strain-life plots were developed for both car and track programs to be used at the early design stage to estimate the fatigue life of the structure. Various material hardening models were evaluated. The strain hardened-isotropic hardening and cyclic-combined hardening were compared. This method improves design cycle time and reduces the warranty by producing a product design that comprehends the fatigue damage resultant from the application of check stop load to the door structure. |
Direct Sensor Solutions for Anti Pinch and Collision Avoidance for Motorized Closures | Motorized closures support the comfort in vehicles to an increasing degree. In the past the use of indirect sensors was an effective low-cost solution for anti pinch [1,2]. The demand for a reduction of the forces affecting the user and for minimized closing times leads to direct sensor solutions. A new aspect is the protection of moving vehicle parts, which we call collision avoidance. This paper deals with system aspects securing the movement area of motorized closures. An analysis is made for sliding doors, trunk lids and tailgates, pointing out the danger zones and the use cases. The result of a QFD (Qualitiy Function Deployment) with respect to the demands of the customer is shown. This leads to a rough description of the requirements for the technical solutions. A technology benchmark is conducted separately for anti-pinch and for collision avoidance. The two applications have distinct requirements; therefore different technological solutions are identified. As an example, the tailgate is examined in detail and a solution for securing the danger zones is presented. A Lab car is equipped and tested. For anti-pinch, a capacitive sensor system is selected and designed. Collision avoidance is realized by adopting a series automotive ultra-sonic sensor. Environmental influences are examined and described. Special integration problems and their solutions for both sensor systems are discussed. The topology of the electronic components is described and an outlook on the future is given. |
Comparing the Harness Cost of Hardwired and Networked Integrated Door Systems | The objective of the research discussed in this paper is to propose a methodology for comparing candidate electrical architectures on a cost basis at the very beginning of the architecture design process. To achieve this objective, historical data concerning the cost of a wiring harness for a driver?셲 door electrical system is analysed along with information on an electrical architecture for the door system of a small four door passenger car. The study is focused around a driver?셲 door electrical system based on LIN and hardwired integration. However, it is concluded that the results are applicable to other types of automotive electrical architectures. |
Evaluation of Door Latch Response to Vertical Loading Conditions | Field research has consistently demonstrated that the risk of occupant death or serious injury in motor vehicle crashes is significantly reduced when occupants are retained within the vehicle.[1][2] The injury prevention benefits of passenger vehicle door systems require that they remain closed during collisions. Federal Motor Vehicle Safety Standards (FMVSS) and SAE Recommended Practices set forth door latch performance requirements to ?쐌inimize the likelihood of occupants being thrown from the vehicle as a result of impact?? Currently, there is not a vertical latch strength requirement for hinged side doors in FMVSS 206. A recent study has raised concerns about latch performance in response to vertical loading conditions. In order to investigate door latch performance in response to vertical loading conditions, the latch must be evaluated using techniques more representative of loading conditions in real world accidents. This study investigates side door latch performance in full vehicle and door system component testing as opposed to the component-only fixture testing outlined in FMVSS 206. Both full vehicle and door system testing showed that the tested side door latches managed forces that were substantially higher than any loads required by FMVSS 206 when subjected to purely vertical loading. |
A case-study about side door closing effort | Door Closing Effort is one of the first impressions a potential customer has about a vehicle. The energy someone needs to give out to push and lock a side door vehicle is easily felt and can enhance the impression of a robust and high quality design vehicle. In other words, Door Closing Effort is one of the issues manufacturers shall look over in order to achieve perfect levels of Human Vehicle Integration (HVI). The aim of this paper is to present a case study of Side Door Closing Effort of a specific Hummer vehicle. It will be shown how door closing effort varies according to several parameters, and how to improve the design and/or production process in view of achieving better effort levels, considering the Hummer case as a background. Several variables that influence on the overall energy of this process have been evaluated, and the physical differences were weighted to demonstrate what really counts for reaching a comfortable level of Door Closing Effort. |
Guidelines for vehicle development based on principles of universal design | In order to fulfill the users' needs, many innovations are included in vehicles. However, not all of these vehicles can be used by People with Special Needs (PSN), due to their technical characteristics and/or adaptation cost, even with the financial incentives offered by Brazilian Government. In this context, the Universal Design (UD) is inserted, where PSN and people without physical deficiencies can use the same vehicle, with little or no adaptation. In order to identify the needs of PSN, interviews were carried out with PSN and exhibiters of automotive products for PSN, in the VII Reatech 2008 (International Fair of Technologies of Rehabilitation, Inclusion and Accessibility), where can be highlighted: to lower the car floor; to improve the door access (increasing width, height and opening angle); to improve the internal space of vehicles; to reduce the cost of adaptation kits; and others. Inclusion programs of the main Brazilian automotive manufacturers were also identified, focusing on kits for automotive adaptation, where some of them were preliminarily evaluated. Finally, general guidelines for vehicle development are proposed, based on principles of UD, results of interviews and a literature review. |
Bake Hardening Steel (BH220) Characterization | The bake hardening effect depends on three parameters i.e. pre-straining, paint baking temperature and paint baking time. The combined effect of all these parameters results into the increase in yield strength, called the ?쐀aking effect?? This paper explains the individual effects of these parameters on the baking value. Tensile test were carried out for the 495 samples baked at baking temperature from 140째C to 250째C with differential baking time of 10, 15, 20, 25 and 30 minutes and differential pre-straining of 2%, 3% and 5%. The differences of yield strength between the unbaked and baked sample were calculated and the increase in yield strength was noted. After these laboratory trials 800 numbers of door outer panels of a small truck were formed and finish painted. The increment in yield strength after component forming and painting was determined by taking tensile samples from three different locations of 5 painted doors. This would help shop floor optimization of the process parameters and the compatibility with various painting process vis a vis increase in bake hardening strength. It is also leading to a future work to understand clearly the correlation between the baking temperature, increase in strength and the micro structural changes. |
Recycling Long Glass Fiber Reinforced Polypropylene Instrument Panel Trim Offal | Production of soft, padded instrument panels (IP's) with a Long Fiber Reinforced Polypropylene (LFPP) substrate have areas for HVAC outlets, air bag doors, IP clusters and glove box doors that are molded over with substrate/ urethane foam/ skin. These openings are subsequently die punched out. These areas are molded over to prevent foam bleed to the backside of the IP during the production foaming process. Typically they are 12% of the total material usage. The punched sections of composite substrate/foam/skin (punch outs) have traditionally gone to landfill, typically at a cost of $0.05/lb. to the Tier 1 supplier. Wipag Recycling in Germany has developed a process whereby the substrate material is recovered from the composite structure, separating the resin from the foam and skin. The resin has 99.8% purity and can be subsequently blended back into virgin resin for production at a specified percentage without statistically varying the physical properties of the LFPP IP substrate. The WIPAG laminate separation process has been in commercial operation at American Commodities Inc. (ACI) in Flint, MI for the past 7 years albeit with SMA, PC/ABS and TPO substrates. With regard to recycling LFPP, traditional wisdom dictates that the material properties of the resin will be reduced after each heat history due to glass fiber length attrition, caused from the processing of the material. This study shows that up to 30% of resin reclaimed from the composite substrate can be added to virgin material with a minimal effect on the properties of the final part. |
Applicability of Different Loudness Models to Time-Varying Sound in Vehicle | Three sound loudness calculation models, including Zwicker instantaneous loudness model, Moore instantaneous loudness model and Moore time-varying loudness model, and the cited Zwicker time-varying loudness model in ArtemiS, were applied to calculate the time-varying loudness of three typical vehicle sounds, in particular. They are steady engine idle noise, impulsive door closing noise and order-swept electric vehicle pass-by noise. Based on the loudness amplitude and time-frequency loudness results, the applicability of the four loudness models to time-varying sounds was analyzed and compared. It was found that, both Zwicker and Moore time-varying loudness models are more reliable than Zwicker and Moore instantaneous loudness models if the sound amplitude and frequency vary tempestuously. And the time-frequency result of Moore instantaneous loudness model can be very helpful to noise source identification and mechanism analysis. |
Invisible PAB Door Development Using Two-shot Molding | Invisible Passenger-side Airbag (IPAB) door system must be designed with a weakened area such that the airbag will break through the Instrument Panel (IP) in the intended manner, with no flying debris at any temperature. At the same time, there must be no cracking or sharp edges at the head impact test (ECE 21.01). Needless to say, Head impact test must keep pace with the deployment test. In this paper, we suggested soft airbag door system that is integrally molded with a hard instrument panel by using Two-shot molding. First of all, we set up the design parameters of IPAB door for the optimal deployment and head impact performance by CAE analysis. And then we optimized the open-close time at each gate of the mold so that the soft and hard material could be integrally molded with the intended boundary. We could make the boundary of two materials more constant by controlling the open-close time of each gate with resin temperature sensor. |
A Study on the Optimization of Body Structure for Rattle Noise by Exciting Woofer Speakers | With the recent development of technologies for interpreting vibration and noise of vehicles, it has become possible for carmakers to reduce idle vibration and driving noise in the phase of preceding development. Thus, the issue of noise generation is drawing keen attention from production of prototype car through mass-production development. J. D. Power has surveyed the levels of customer satisfaction with all vehicles sold in the U.S. market and released the Initial Quality Study (IQS) index. As a growing number of emotional quality-related items are added to the IQS evaluation index, it is necessary to secure a sufficiently high quality level of low-frequency speaker sound against rattle noise. It is required to make a preceding review on the package tray panel, which is located at the bottom of the rear glass where the woofer speakers of a passenger sedan are installed, the door module panel in which the door speakers are built. Based on the theoretical background of robust design, this study seeks to suggest design criteria that are insensitive to the noise factors of the package tray panel. |
Real-time Simulation of a Vehicle Door Locking Mechanism on a Hardware-in-the-Loop Platform | An automotive side door latch release mechanism has been modelled for the locking and unlocking vehicle functionality in Dymola. The performance of the developed door lock model is evaluated against an existing model of a similar door locking/unlocking system in Stateflow. The model performance is also compared with measurements from a real vehicle door latch. The model is converted into a Simulink model and built for a real-time environment such as the dSPACE target with a fixed step size solver. It is shown that a step size as small as 1 ms can be used for real-time simulation without task overrunning in the real-time target. The model is also benchmarked on a multiprocessor setup as multiprocessor simulators are common in system-level networked Electronic Controller Unit (ECU) testing facilities for implementing high fidelity closed loop models of integrated ECUs and actuators. It is proven that the developed door lock model in Dymola can be built and executed on a multiprocessor platform and there is much potential on the use of such models for future work in ECU testing. |
Capitalizing on the Increased Flexibility that Comes from High Power Density Electrothermal Deicing | This paper introduces a recent development in electrothermal heating technology that enables increased power densities on the leading edge of aircraft wings for the purpose of de-icing. Key aspects of this development include a high temperature heater mat, minimal thermal interference between the heating element and leading edge skin, a high quality bond of the heater to the skin and a power density profile that compensates for non-uniform thermal loads on the leading edge skin. Icing tunnel testing results corroborate the value of these key aspects in enabling operation at extreme power densities, even to the point of achieving full evaporative anti-icing operation under Intermittent Maximum conditions. The advent of higher power density capabilities has opened the door to new approaches to electrothermal deicing that were previously impracticable. Some of these new approaches and their benefits are presented. |
Vehicle Roof Strength Test Procedure | This SAE Recommended Practice establishes a uniform laboratory test method to evaluate the strength characteristics of roof systems. The test procedure is intended to provide reliable and repeatable results and to permit numerical comparisons. A test is conducted in which the vehicle roof system is loaded under controlled laboratory conditions. Structural strength measurements are obtained under load application angles chosen to concentrate forces on the forward portions of the roof panel and roof supporting structure. |
Passenger Car Door System Crush Test Procedure | This SAE Recommended Practice establishes a uniform laboratory test method to evaluate the capability of passenger car door systems to resist a concentrated lateral inward load. The procedure is intended to provide repeatable results and to permit numerical comparisons. A test is conducted in which the door and related structural members of the vehicle are loaded under controlled laboratory conditions. Structural strength measurements obtained under these conditions are reproducible. Background information and rationale for the test procedures described in this Recommended Practice are provided in the Appendix. |
Door-Closing Sound Quality Improvement Process Based on Beamforming Method, Wavelet Analysis, and Component Design Optimization | Door-closing sound quality is a very important noise, vibration, and harshness (NVH) attribute since it may have a significant impact on customers??perception, recognition, and luxury sensation of an automobile brand. Therefore, its evaluation methodology and design process have been one of the research and engineering efforts for all NVH organizations in the automotive industry. In many cases, the resolution of a door-closing sound quality issue lacks a systematic approach, and engineers rush to work when an issue surfaces. While subjective evaluation may easily find a door-closing sound problem, it oftentimes cannot directly pinpoint and go right to the root cause of the issues, and engineers could only guesstimate the possible relevant structural components based on past experiences. In this work, a door-closing sound quality development process, which has already been implemented in vehicle programs, is summarized and presented. The process involves a systematic workflow in a relatively short turnaround time. It begins with the beamforming method to carry out the sound source localization to facilitate the accurate determination of the key areas that impact the door-closing sound quality and then followed by objective measurements to acquire the sound data for the examination of the temporal behavior and spectral content processed by the wavelet analysis. After a better understanding of the key components along with the sound characteristics obtained, the effort is then focused on the investigation of the component mechanisms and optimization of the relevant hardware kinematics. A case study based on a high-end passenger vehicle is presented, and in this particular example, it is found that the door latch design and weather strip on the upper window frame are the critical components. Once the design proposal is implemented, the door-closing sound quality has finally met the program target. |
An Overview of Automotive Wind Noise and Buffeting Active Control | As the wind speed increases, the contribution of wind noise gradually exceeds other noise sources, affecting comfort. First, the classification of automotive wind noise is discussed in detail according to the formation mechanism, sound analogy, and pressure type. Then the wind noise evaluation and development tools are summarized. Finally, the characteristics and control means of vehicle window-induced buffeting noise are discussed. Considering the appearance and field of view, it is currently difficult to control side window buffeting based on passive methods. Therefore, the proposed method of actively controlling the window opening size, actively opening multiple windows, and even releasing an inverse phase sound source based on control logic has a good application prospect. |
Wind Noise Contribution Analysis | This article is motivated by observations of the wind tunnel measurement data acquired during benchmarking and program development for a variety of passenger vehicles over the years. In wind noise development, contribution analysis is a common practice to screen and identify the most significant sources and paths. In order to shed light on the whole picture of the contribution analysis, the work presented in this article falls into two categories. One is the analysis of underlying mechanisms for a better understanding of the phenomena observed in the contribution results. The other is the summarization of wind noise contributions obtained by wind tunnel testing for some representative subsystems, e.g., the contributions based on different reference states, the effect of grilles, underbody, acoustic glass, and auditory masking. A close look at the obtained numbers for each vehicle reveals that all these numbers have their intrinsic characteristics, and the same number may not tell the same story. The components with the same design, cost, and quality behave differently in vehicles with different wind noise levels. This work shows that contributions are generally reference-based and vehicle-dependent, and vary when the reference state is deviated even for the same vehicle. The same subsystem contributes more to a quiet vehicle than a mediocre vehicle, thereby a direct comparison of contributions among different vehicles is unfair and biased against quieter vehicles. As a first approximation, a quantitative estimation is derived to promote a qualitative understanding. It is used to facilitate a fair comparison of contributions, which are based on different reference states from either the same vehicle or different vehicles. It also implies that a vehicle with superior wind noise performance carries with it a much more stringent standard in subsystem design than an average vehicle even though their contribution targets are similar. The understanding of the work presented in this article would further benefit the interpretation of various contribution results, their comparison, and subsystem target setting. |
Finite Element Model Reduction Applied to Nonlinear Impact Simulation for Squeak and Rattle Prediction | Increasing demand for simulation accuracy often leads to increased finite element model complexity, which in turn, results in higher computational costs. As a provision, component mode synthesis approaches are employed to approximate the system response by using dynamic substructuring and model reduction techniques in linear systems. However, the use of available model reduction techniques in nonlinear problems containing the contact type of nonlinearities remains an interesting topic. In this paper, the application of a component mode synthesis method in squeak and rattle nonlinear simulation has been investigated. Critical regions for squeak and rattle of the side door model of a passenger car were modelled by nonlinear contact definition in finite element simulation. Craig-Bampton model reduction method was employed to substructure the finite element model while keeping the nonlinear contacts in the model. The model response was evaluated using the modal assurance criterion, frequency response analysis and contact force magnitude in comparison with the baseline model. Results showed that a great reduction in computational time (about 98%) can be achieved while the accuracy of the system response was maintained at an acceptable range for the intended application for squeak and rattle simulation. Although the prediction of impact events in time was done accurately, the contact force magnitude was estimated with average error of 2.5% to 22%, compared with the baseline results. The outcomes of the study show that to empower squeak and rattle prediction by including contact interfaces in finite element simulations, implementation of the model reduction approach can compensate the simulation cost. |
Passenger Car Door Closing Effort Prediction Using Virtual Simulation and Validation | In the automobile industry, the door closing effort spells out the engineering and quality of the vehicle. After the visual impact a vehicle has on the customer, the doors are most likely the very first part of the vehicle he/she encounters, to enter and exit the vehicle. One of the customer?셲 very first impressions about the quality of the car is given by the behavior of the doors when opening and closing, the swinging velocity and the energy that is required to obtain a full latching that the door makes when closed by the user. Door closing effort gives an indication of how good or bad the vehicle is engineered. The purpose of this paper is to propose modifications in the door system which help in reduction of door closing effort or velocity by two different methods, EZ Slam Door and Bungee Rope. In this paper, parameters like hinge friction, hinge axis inclination, sealing, latch and air bind effect are analyzed which affect door closing effort. A virtual model is prepared in MSC.ADAMS to evaluate door closing velocity through calculating energy contribution by each parameter. Door closing effort or velocity is calculated for the existing model and to improve the existing scenario, design modifications are proposed. These design modifications after implementation have shown 20% reduction in door closing effort or velocity. Physical validation was done, and results were found in line with the virtual simulation. The correct method for door closing effort prediction is proposed based on real world customer usage pattern. |
Deep Generative Design Models for Improved Door Frame Performance | Significance of CAE simulation thus is increasing because of its ability to predict the failure faster, also lot of design combinations can be evaluated with this before physical testing. Frame stiffness of side doors is one of the major criteria of a vehicle closure system. In most cases, designers around the globe will be designing same or very similar side door frame structures recurrently. In addition, in the current growing trend having an optimized side door frame design in quick time is very challenging. In this investigation, a new artificial intelligence (AI) approach was demonstrated to design and optimize frame reinforcement based on machine learning, which has been successful in many fields owing to its ability to process big data, can be used in structural design and optimization. This deep learning-based model is able to achieve accurate predictions of nonlinear structure-parameters relationships using deep neural networks. The optimized designs with optimization objectives as deflection is obtained efficiently and precisely using Bayesian Optimization algorithm. Deep learned computational results were validated by the experimental results. Furthermore, the developed deep neural networks show how various design sections of door frame structures behave and how it can be used as a reference for future door design through deep generative model techniques. Keywords: Door Frame Reinforcement, Deflection, Deep neural networks, Bayesian Optimization algorithm |
1D Modeling of HVAC Unit Air Flow for Automatic Climate Control Simulations | Advanced control techniques are widely used in different automotive applications including climate control. Significant costs associated with the development and calibration of such controllers can be reduced if these tasks are conducted in a virtual environment. Such a virtual environment can be developed by integrating the controller with the system model. Different scenarios can be then simulated to make sure functional objectives of the system are met. 1D models provide the necessary level of accuracy without imposing extra computational cost in such virtual environments. As such, they are perfect candidates for model, hardware or software-in-the loop validation benches for controls. Performance of a heating, ventilation and air-conditioning (HVAC) system can be controlled through the settings of the components like mode door, blend door, recirculation door, blower, and the compressor. In an automatic climate control (ACC) system, these factors are automatically actuated to achieve thermal comfort. For development and calibration of ACC systems, virtual setups with a model of HVAC unit can be used. In this case, the model should capture the flow inside the HVAC unit which could be impacted by the door positions. This paper proposes a 1D model for HVAC unit air flow, where components such as mode door, blend door, recirculation door, and blower are modeled and calibrated. Capability of the model to predict temperature values along the unit is then validated against test data. The promising results demonstrate the model potential in ACC virtual development and calibration. This can reduce the number of tests needed and help minimize the cost, effort, and possible delays in product development. |
Analysis of Discretization for Transient Impact Loads on Door Closing | The transient impact load generated by door closing is used as the input of the closing condition, which is an important part of door system investigation. In this article, the basic theory of transfer path analysis (TPA) is introduced to handle the abnormal vibration of the front-left door with the glass down stall position of a certain vehicle during the closure. The transient impact loads are discretized under the closed door and obtained using the inverse matrix (IM) method in TPA. Vehicle test and bench test are conducted. The closed door is subjected to the transient impact loads of the sealing strip and the latch on the body side. In the vehicle test, acceleration sensors are pasted on the target point and the reference point on the door to obtain the acceleration vibration response upon the door closure. In the bench test, when the hammer strikes the excitation points, the frequency response functions (FRFs) from these points to the reference point and to the target point are recorded by the acceleration sensors. The vibration amplitude of the front-left door with the glass down stall position is taken as the criterion. Finally, a reasonable discretization number of the door-closing transient impact loads is determined, which provides guidance for subsequent research of the door system. |
Air Bind Effect on Door Slam Durability Performance | In the vehicle development process, the door slam durability assessment is of significant importance in the estimation of fatigue life for body closure system. So far, various exertions have been taken into consideration to better represent the door slam simulation for door durability performance. Nowadays, with computer aided engineering (CAE) being extensively implemented, simulation procedures are constantly being investigated in order to get precise outcomes as physical testing. In a real world scenario, the customer closes the door frequently against the sealed cabin which offers the cabin pressure to close. The cabin pressure acts in the opposite direction of door closing providing the damping effect and minimizes the overall damage to the structure. Currently, simulations are focused on determining the total energy required for closing the door by summing up the energy lost in the weather seal and latch. Often the energy required to overcome the air-bind effect is neglected in the analysis. This work addresses the air bind effect on structural durability performance of swing door, simulating customer usage over a 10-year vehicle lifecycle with using stress analysis in explicit solver and strain-life analysis in fatigue solver. |
Prediction of Automotive Side Swing Door Closing Effort | The door closing effort is a quality issue concerning both automobile designers and customers. This paper describes an Excel based mathematical model for predicting the side door closing effort in terms of the required minimum energy or velocity, to close the door from a small open position when the check-link ceases to function. A simplified but comprehensive model is developed which includes the cabin pressure (air bind), seal compression, door weight, latch effort, and hinge friction effects. The flexibility of the door and car body is ignored. Because the model simplification introduces errors, we calibrate it using measured data. Calibration is also necessary because some input parameters are difficult to obtain directly. In this work, we provide the option to calibrate the hinge model, the latch model, the seal compression model, and the air bind model. The door weight effect is geometrically exact, and does not need calibration. The capabilities and accuracy of the developed model are demonstrated using the front and rear doors of a production vehicle. |
Mixture Distributions in Autonomous Decision-Making for Industry 4.0 | Industry 4.0 is expected to revolutionize product development and, in particular, manufacturing systems. Cyber-physical production systems and digital twins of the product and process already provide the means to predict possible future states of the final product, given the current production parameters. With the advent of further data integration coupled with the need for autonomous decision-making, methods are needed to make decisions in real time and in an environment of uncertainty in both the possible outcomes and in the stakeholders??preferences over them. This article proposes a method of autonomous decision-making in data-intensive environments, such as a cyber-physical assembly system. Theoretical results in group decision-making and utility maximization using mixture distributions are presented. This allows us to perform calculations on expected utility accurately and efficiently through closed-form expressions, which are also provided. The practical value of the method is illustrated with a door assembly example and compared to traditional random assembly methods and results. |
A Study on Various Structural Concepts of Automotive Door Trim | An automobile door is a complex module, which consists of various fixed and movable subassemblies and components. Parameters such as safety, vehicle dynamics, aesthetic and strength are critical while designing the door assembly. Apart from the above, the design of door trim should minimize BSR (buzz squeak and rattle) at vehicle running conditions. Stiffness is one of the key engineering requirements which if not optimized will result in higher BSR levels and failure of the door trim components. In this study, more importance is given to optimize the stiffness of door trim. As per DVP (design verification and planning) standards of the OEMs, the range of deflection for the plastic trim parts is defined considering the conditions, comfort level and location of use. If stiffness is higher than the requirement, the door trim plastic parts are harder and will violate the quality and safety norms. If it is lower, then trim parts will not meet the functional requirements and safety norms. To achieve the optimized stiffness within the range, various design proposals capturing different structural concepts are constructed and analyzed. |
Internal Pressure Characteristics when Evaluating Dynamic Door Blow Out Deflection | Wind noise is one of the most influential NVH attributes that impact customer sensation of vehicle interior quietness. Among many factors that influence wind noise performance, the amount of dynamic door deflection under the pressure load due to fast movement of a vehicle plays a key roll. Excessive deflection could potentially lead to loss of sealing contact, causing aspiration leakage, which creates an effectual path through which the exterior aerodynamically induced noise propagates into the vehicle cabin. The dynamic door deflection can be predicted using CFD and CAE approaches which, in addition to modeling the structure correctly, require a correct pressure loading composed of external and internal pressure distributions. The determination of external pressure distributions can be fulfilled fairly straightforward by using commercial CFD codes such as Fluent, Star CCM+, Powerflow and others. However, the capability of predicting the internal pressure due to high wind speed outside of a vehicle has not been developed. This work looks into the internal pressure characteristics associated with the dynamic loading setup that is required for analytical efforts. The work is based on the wind tunnel measurement data involving several vehicles. By comparing the measured internal pressure data, along with CAE results, the issues are summarized and a conservative internal pressure load value is recommended. |
Structural Integrity Evaluation of Plastic Welding (Heat Stake) Tower in Door Trim Panels of Vehicles Using Finite Element Method | Structural integrity is a characteristic that must be evaluated during development of plastic parts as door trim panels. One of the critical areas in door trims is the interface between different parts that often use heat stakes due to process capacity and low costs. To predict issue on those interfaces, a methodology combining finite element analysis (FEA) and physical test results was applied to drive design in two door trim designs, with different material combinations. Aiming to support FEA conclusions, physical tests were performed to determine the maximum retention force that a heat stake withstands, indicating values about 168N for heat stakes of medium impact polypropylene blend >PP+EP(D)M-T<. and 216N for stakes of unfilled polypropylene copolymer >PP<. These values were used as upper limits for reaction forces provided by FEA in each heat stake under a load of 600 N at Pull Handle. The results for first door trim design indicated no structural issue in any heat stake, what generated a weld process investigation. Its conclusion indicated as root cause the weld quality. The results for second door trim design indicated an issue in one heat stake that required a relocation to redistribute the load. After including a new heat stake and redistributing their position, simulation indicated lower efforts, meeting the requirements. This methodology proved to be efficient to evaluate heat stakes performance during door trim development process. |
Small Overlap Impact Countermeasure-Front Door Hinge Pillar Dual Box | Since the inception of the IIHS Small Overlap Impact (SOI) test in 2012, automotive manufacturers have implemented many solutions in the vehicle body structure to achieve an IIHS ?쏥ood??rating. There are two main areas of the vehicle: forward of vehicle cockpit and immediately surrounding the vehicle cockpit, which typically work together for SOI to mitigate crash energy and prevent intrusion into the passenger zones. The structures forward of vehicle cockpit are designed to either 1) absorb vehicle energy from impact to the barrier, or 2) provide enough strength and rigidity to aid deflection of the vehicle away from the barrier. The structures which are immediately surrounding the vehicle cockpit (known as pillars and rocker/sills) are traditionally components designed to be highly rigid sheet metal panels to protect the occupant during crash events. This paper focuses on a concept for a portion of the cockpit structure that combines energy absorption and high rigidity structure, which are not typical in this area of a vehicle?셲 architecture. Using CAE methods, it is observed that a vehicle?셲 SOI structural rating will be enhanced utilizing the presented concept. |
Evaluation of Minimum Door Closing Velocity Using Analytical Approach | Door closing velocity (DCV) is one of the important design parameter for door durability performance. The closing velocity varies with the design parameters and physical properties of the door. The variation in door closing effort may increase or decrease the durability of the door and body components, this can be a concern when the overall vehicle durability performance is considered. This paper gives a mathematical model to calculate the door closing effort accounting the energy sink from various door design parameters such as door seal, latch, hinge, door weight, checkstrap and cabin-pressure. In addition to this, the MS-Excel based computation tool has been developed, which aims to calculate the door closing velocity and energy contribution from each design parameter. This tool is very interactive and effective for durability engineer and helps in improving the quality of vehicle door design. This paper also provides the result comparison study with CAE approach for design parameters as seal stiffness, latch, hinge, door weight and checkstrap. |
Innovative Door Design for Commercial Vehicles | Design of body structures for commercial vehicles differs significantly from automotive due to government, design and usage requirements. Specifically, heavy truck doors are not required to meet side impact requirements due to their height off the ground as compared to automobiles. However, heavy truck doors are subjected to higher loads, longer life, and cannot experience permanent deformation from overload events. Aluminum has been used intensively in commercial vehicle doors and cab structures for over 50 years by several different manufacturers in North America. It has been only in the last few years that aluminum has appeared in automotive door structures other than in high-end luxury vehicles. Commercial vehicle customers are expecting the same features found in premium automobiles resulting in opportunities to learn from each other's designs. In order to optimize the strength and weight of a commercial vehicle door, a new aluminum intensive structure was developed. The new structure featured a unique architecture that was the first in the industry to use a multi-cavity aluminum extrusion joined to stamped sheet reinforcements in order to provide a direct load path between the hinges and the latch. The shape of the extrusion also allows the use of a one piece glass and door mounted mirror. The ?쐀arn door??architecture of the inner structure of the door allowed for gauge optimization of the both the inner and outer stampings, the two largest and heaviest components of the assembly. Additionally, the use of an extrusion allowed for a single drop glass for improved visibility and the ability to use a door mounted mirror with only one extra reinforcement. Overall the design architecture used in the new doors provide best in class structural performance, sealing and features normally found in luxury automobiles for the first time in the heavy truck industry. |
Striker with bumper implementation to improve chucking noise issues | Investing in quality as added value to products becomes a means of guaranteeing satisfaction as well as customer loyalty, making it competitive in its respective segment. In the automotive business, this has not been different, It can observed a progress in the perception and customers demand in quality in the last few years. At the same time, that the industries need to guarantee the cost and time of response to the dissatisfaction of the customers. In this project, was possible to implement a locking door concept, with an effective solution to the door vibration problem in a B platform, vehicle model in South America. |
The Study of Optimization of Sliding Door Effect | A sliding door system is one of the vehicle door types, which is generally applied to the MPVs. The Sliding door is contains three rails (an upper, a center, and lower rail), which are mounted on body structure, and three rollers (the upper roller, the center roller, Lower roller), which are mounted on the sliding door side. The system is different from a swing door, rotated by hinge axis. To set up sliding door layout for better performance, predict operating force is one of the main factors, But The door moving trace is on three-dimension, hard to calculate and predict. So in this study, it is an object to analyze the impact between the main factors affecting the performance of the closing and open performance and the sliding door through the study formula and a layout scheme for ensuring the best operating performance of the sliding doors. |
Automatic Drilling and Fastening System for Large Aircraft Doors | Electroimpact has developed a system for drilling and fastening of cargo door structures which efficiently addresses many of the manufacturing challenges that such parts present. Challenges to door automation include 1) the presence of an inner skin that must be processed, in addition to the outer skin, and 2) a stiff frame structure, which makes the clamping and drilling processes that are typical to automated fastening machines very unforgiving of any errors in workpiece positioning. In this case, the manufacturing cell was to be installed in an existing facility with very limited ceiling height, further complicating the system and process design. New methods were devised to solve these problems, and the solutions found will likely have utility in future applications. |
In-Situ Characterization of Vibrations from a Door Mounted Loudspeaker | In the automotive industry, there is an increasing need for gaining efficiency and confidence in the prediction capability for various attributes. Often, one component or sub-system is used in a number of car models of one vehicle platform. Many of these components are potential sources of noise, vibration and squeak and rattle. In order to provide an early prognosis, vibro-acoustic source characterization in combination with the source-to-response transfer behavior are required. This paper describes the process of predicting the vibrational behavior due to a woofer, which could induce squeak and rattle, on a door panel. Blocked forces, determined indirectly in-situ by frequency response functions and operational accelerations, were used for quantifying the source activity. Those forces were in a second step loaded on to a finite element model in order to predict the response when the speaker was mounted to another position in an upcoming car model. Prior to this, comparisons between the measured and simulated response for the same car model were made, with satisfying agreement. |
Trimmed Door Audio Response Hybrid Modeling Assessment | The door response to audio excitation contributes to the overall performance of a vehicle audio system on several items: acting as a cabinet, it influences the loudspeaker response, but it also radiates unwanted sound through the inner door panel. Associated design issues are numerous, from the loudspeaker design to door structure and inner panel definition. Modeling then appears as an unavoidable tool to handle the acoustic response of the loudspeaker in its actual surrounding as well as the door inner panel radiation. In the low frequency range (<300 Hz), the loudspeaker is conveniently modelled using the classical Thiele&Small 1 D model. The interaction with the door and the acoustic surroundings requires a more detailed Finite Element modeling considering the acoustic loads on both sides of the loudspeaker membrane and the force at the loudspeaker frame interface with the door structure. The proposed hybrid modeling is first assessed by comparison of the computed and the measured membrane?셲 displacement. An update of the T&S parameters is performed in order to optimize the model. Then, the computed loudspeaker frame displacement and the acoustic loads may be checked against measurement. Finally, the computed vibrational response of the trimmed door is compared to an extensive 3D LASER measurement. Such an analysis allows the loudspeaker membrane displacement control as well as the inner door panel?셲 motion that may radiate unwanted sound. Previously proposed indicators are used to quantify the door audio performance. |
Vehicle Side Safety Enhancement through Door Intrusion Barrier Analysis and Recuperation | The automobile industry is making huge strides to improve vehicle and occupant safety. A lot of safety improvements and modifications have been made in the past decade. But the side impact is still overlooked as not much has been improved for side safety despite most of the accidents and collisions happen to the side of a vehicle. Door intrusion barriers are the primary protection feature along with A, B and C pillars. Crashworthiness mainly depends on the position, cross-section and material of the intrusion barrier. So, our work mainly focuses on finding the optimum position, choosing the correct cross-section and finding the right material for the intrusion barrier. The objective of this project is to minimize the damage to the side of the vehicle by increasing its crashworthiness thereby reducing passenger injuries. A model of a vehicle door has been designed in Solid Works and various cross sections of door intrusion barriers like circular, rectangular, H-section, I section, E and C section have been developed. The crash test has been conducted according to New Car Assessment Program (NCAP) norms and the best possible configuration with highest safety level has been found. The barrier developed successfully reduced deformation by 36.667% and was subjected to a much lesser stress which was 28% lower than the existing barriers. |
Virtual Simulation of Door Slam Test, Study of Relative Sensitive Parameters and Correlation with Physical Test | Door slam test is one of the important durability tests in door design and development. Door requires to meet certain performance requirements like it should close properly (no metal to metal contact), there should not be any leakage, and closing operation should be smooth & with minimal effort and it should survive the life of the vehicle. Virtual simulation of door slam test, correlation with physical test results and effect of various parameters like seals stiffness are demonstrated in this study. Slam Analysis was carried out in LS-Dyna solver before physical test. This not only helped in avoiding initial structural design flaws, but also helped us in deciding door latch position, effect of mass distribution in the door and study of force distribution between primary seal, secondary seal and door latch. Primary and secondary seals played a critical role in the analysis. An intended length of both the seals was tested first to get its stiffness curve. Then it was modeled in the way that stiffness of one beam represented the stiffness of testing length. An in-house developed physical test was carried out for the intended cycles. A good correlation between simulation and test results is achieved. Overall detailed study of door slam test, simulation methodology and effect of various relative parameters on performance has become very important step in design and development of door assembly. |
Automotive Door Opening Durability Simulation Using Detail Checkstrap Mechanism | In automotive design space, door opening durability is one of the important design attribute to build a door structure. Customer often interact with door while ingress and egress a vehicle and that builds a perception of vehicle in customer?셲 mind. Now days, Computer Aided Engineering (CAE) is used extensively to simulate the real time door opening and closing event for designing the door structure for durability performance. Early prediction of durability performance and developing the countermeasures saves great amount of time and cost. This paper provides a brief study of detail checkstrap mechanism and its influence on door durability performance. Door checkstrap plays an important role in swing door design, it assists the door opening and closing with the help of check arm profile guided by roller and spring. This allows the load transferred from door to body through checkstrap first and then through hinges. The load interval between door full open to door over-open becomes critical for door durability performance. During this event, the majority of energy absorbed by the checkstrap mechanism and attached door & body components. Hence, the checkstrap mechanism representation is very important for the door durability simulation. Door dynamic analysis for overopen load is performed in LSDYNA solver and fatigue analysis is performed in nCode. |
A Robust Structure Analysis on Automotive Door Armrest | An automobile door is one vital commodity which has its role in vehicle?셲 function, strength, safety, dynamics and aesthetic parameters. The door system comprises of individual components and sub-assemblies such as door upper, bolster, armrest, door main panel, map-pocket, handle, speaker and tweeter grille. Among them, armrest is an integral part which provides function and also takes care of some safety parameter for the customers. The basic function of an armrest is to provide ergonomic relief to occupant for resting his hand. Along with this, it also facilitates occupant safety during a side impact collision by absorbing the energy and not imparting the reactive force on occupant. Thus an armrest has evolved as a feature of passive safety. The armrest design should be stiff enough to withstand required elbow load condition with-in the acceptable deflection criteria. On the other hand, armrest has to absorb the dynamic force by deflecting proportionally to the side impact load. In this study the various structure of armrest was analyzed to strike an ideal zone between functional and safety parameters. The scope is to improve the functional requirement, i.e., the side impact metrics and also to reduce the variation among the noise factors such as manufacturing tolerance, location of side impact and BIW rigidity. For this, DFSS way of approach is handled to optimize a robust design which provides enhanced passive safety for customer. This optimized passive safety armrest design can be used for upcoming programs and the development lead time can be reduced considerably. |
A Study of Design Methodology to Develop Improved Door System of a Vehicle | In the past few years, technological innovations in the automobile industry took vehicle performance to the next level. One such innovation is frame integrated panel door. This type of door helps automobile companies to have the advantages of both conventional panel and frame type doors. Though it has a good number of advantages, there are some drawbacks too. It requires improvements in its quality, NVH performance, weight and etc. Quality of a door is low due to the limitations in structural design and manufacturing technologies. And it is difficult to have a robust structure which leads to degradation of key performing factors such as NVH. For a lightweight vehicle, it is important to design an optimized structure for saving weight, without compromising its performance. In order to overcome these drawbacks a new optimized design structure is required for door system. This Research paper is about a systematic design methodology for Development of a new optimized door structural design by a comprehensive engineering design analysis of existing design constrains and drawbacks. The design methodology is described as below. Step 1 is the System analysis. The correlation of all components constituting the door was schematized and their functional relationships were modeled to analyze door system. Step 2 is the Problem analysis. The occurrence-sequence mechanism for problems was enumerated and the root cause was analyzed by investigating up to the sub ordinate level components in door system. Step 3 is deriving the concepts. Using the theory of inventive problem solving techniques, new concepts were derived from a variety of parameters such as new structures, materials and manufacturing processes. Step 4 is the Specification optimization. New design is evaluated for possible optimization in its specifications. Based on evaluation result optimal specifications are selected. Step 5 is the performance evaluation. The performance is verified by evaluating the new structure of the system. Following the above design process, a new door system with an initial design objective was developed. |
A Development of the New Mechanism for Preventing Door Opening in Side Impact Test | During a new vehicle development process, there are several requirements for side impact test that should be confirmed. One of the requirements is the prevention of door opening during side impact test. Even though there are many causes for door opening problem, this study deals with inertia effect by impact energy. Until now, there have been two classical methods to prevent car door from opening in side impact. One is the increment of the inertia resistance by increasing the mass of the balance weight and the spring force. The other is the application of the blocking lever. Unfortunately, in spite of our efforts, the door opening problem occurs occasionally. Therefore, to improve the problem fundamentally, this paper proposes a new blocking lever mechanism that work similar to ball-point pen structure. The proposed mechanism fixes the blocking lever when the opening directional inertia force is applied to the door outside handle during side crash. With this, it is possible to prevent vehicle door from opening during side impact. Additionally, it is possible to reduce the weight of door outside handle and the spring force. |
Multidisciplinary Design Optimization of Automobile Tail Door | Stringent emission norms by government and higher fuel economy targets have urged automotive companies to look beyond conventional methods of optimization to achieve an optimal design with minimum mass, which also meets the desired level of performance targets at the system as well as at vehicle level. In conventional optimization method, experts from each domain work independently to improve the performance based on their domain knowledge which may not lead to optimum design considering the performance parameters of all domain. It is time consuming and tedious process as it is an iterative method. Also, it fails to highlight the conflicting design solutions. With an increase in computational power, automotive companies are now adopting Multi-Disciplinary Optimization (MDO) approach which is capable of handling heterogeneous domains in parallel. It facilitates to understand the limitations of performances of all domains to achieve good balance between them. The paper presents the MDO of a Tail door of a sports utility vehicle (SUV) which is carried out at the stage where major structural design has been finalized, and the only gauge of the tail door panels can be taken for design variables. The objective of the exercise was to minimize the mass while meeting various performance parameters. Modal and frequency response function (FRF) load cases are considered for noise vibration and harshness (NVH) domain and stiffness load cases for durability domain. Crashworthiness domain load cases for the tail door were not considered here because crash norms are not applicable for rear impact. Response surface based optimization method has been selected for the optimization considering resource availability and dexterity of being applied in various domains. A sensitivity study was used to identify critical panels for each performance parameter. Broken constraint charts were studied to identify the load cases which limit the mass reduction opportunity. The study showed twelve percent of mass saving which is significant for automotive doors. |
Effect of PVC Skin and Its Properties on Automotive Door Trim Inserts | Plastic plays a major role in automotive interiors. Till now most of the Indian automobile industries are using plastics mainly to cover the bare sheet metal panels and to reduce the weight of the vehicle along with safety concerns. Eventually Indian customer requirement is changing towards luxury vehicles. Premium look and luxury feel of the vehicle plays an equal role along with fuel economy and cost. Interior cabin is the place where aesthetics and comfort is the key to attract customers. Door Trims are one of the major areas of interiors where one can be able to provide premium feeling to the customer by giving PVC skin and decorative inserts. This paper deals with different types of PVC skins and its properties based on process constraints, complexity of the inserts. Door trim inserts can be manufactured by various methods like adhesive pasting, thermo-compression molding and low pressure injection molding process etc. Considering process feasibility and PVC skin manufacturing constraints, it will be a challenge to decide the specifications of the PVC skin to achieve good quality product. The objective of this paper is to review the effect of PVC skin & its properties on door trim inserts using Low pressure injection molding and discuss steps involved in selecting the appropriate PVC skin. |
A Study on Optimization of the Ride Comfort of the Sliding Door Based on Rigid-Flexible Coupling Multi-Body Model | To solve the problem of serious roller wear and improve the smoothness of the sliding door motion process, the rigid-flexible coupling multi-body model of the vehicle sliding door was built in ADAMS. Force boundary conditions of the model were determined to meet the speed requirement of monitoring point and time requirement of door opening-closing process according to the bench test specification. The results of dynamic simulation agreed well with that of test so the practicability and credibility of the model was verified. In the optimization of the ride comfort of the sliding door, two different schemes were proposed. The one was to optimize the position of hinge pivots and the other was to optimize the structural parameters of the middle guide. The impact load of lead roller on middle guide, the curvature of the motion trajectory and angular acceleration of the sliding door centroid were taken as optimization objectives. In the first scheme, multiple sets of sample models were obtained by using orthogonal experimental design and approximate surrogate models were established with the method of RSM, Kriging and RBF. However, the optimum solution couldn?셳 be obtained because the optimization objectives are highly nonlinear with respect to the design variables. To solve the problem, an improved optimization method of hierarchical encryption was adopted and obtained the optimum solution finally. In the second scheme, the structural parameters with the best ride performance was obtained by using the evaluation function method. The proposed study improves not only the ride comfort of the sliding door, but also has great significance for the preliminary design and development of the sliding door. |
Minimizing the Rattling of Door Glass | Significant effort has been expended to improve the sound made by a closing car door. This study focuses on reducing door glass rattle sounds, not only evaluating the rattle influence of door glass support but also introducing an approach to reduce glass rattle noise by using sealing components. The first part of the study is dedicated to minimizing vibration. A jig is constructed to evaluate the influence of a door glass support on the rattling. The jig is employed so that the glass meshing between the A and B pillars can be controlled; the glass holder moves in the x- and z-directions and the belt molding moves in the y-direction. An impact hammer test was adopted for investigating door glass rattle. The frequency response obtained via impact hammer testing is analyzed by varying the glass support points and important factors that should be considered in early design stages are obtained. The second study is about optimizing vibration absorption. A glass run, door-side weather-strip, and body-side weather-strip are used to absorb vibration. The glass run section is created through the TRIZ technique. Performance evaluation of the rattle in this section show that the damping speed improved by 35% compared with the damping speed of the existing glass run, rendering it possible to significantly reduce glass rattle noise. This study suggests an approach to reducing both the vibration caused by DR BIW and door glass rattle noise using weather-strips. This research also shows that the door-side weather-strip is the most useful in reducing rattle noise. This study provides greater insight and access to the door glass rattle problem. |
Door Audio Response Hybrid Modeling and Assesment | The door response to audio excitation contributes to the overall performance of the audio system on several items. First, acting as a cabinet, it influences the loudspeaker response. Second, due to the door trim inner panel radiation, the radiated power is disturbed. A third effect is the regular occurrence of squeak and rattle, that will not be considered at this stage. Design issues regarding these attributes are numerous, from the loudspeaker design to door structure and trim definition. Modeling then appears as an unavoidable tool to handle the acoustic response of the loudspeaker in its actual surrounding. Since most of the issues are related to low frequency excitations (<200 Hz), and considering the fact that several loudspeaker references may be used in the same door, it was chosen to model the system in a hybrid manner: the electro-dynamical behavior of the speaker is modelled using a classical 1D modelling (Thiele and Small) while the door vibro-acoustic behavior is modelled by means of Finite Elements. After the vibroacoustic coupling between the loudspeaker and the door is fully described, transmission paths are investigated, showing possible simplifications. Electroacoustical indicators are then proposed to control the door design regarding audio quality issues. Sensitivity of the indicators to some design variables will then be shown. |
Simplified CAE Model Technique to Predict Crush Performance of Identical Sized Passenger Vehicle Doors | This paper highlights a simplified CAE model technique, which can simulate and predict door crush strength performance quickly. Such quick models can be used for DFSS and Design change studies. The proposed method suggests an equivalent sub model technique using only the door beam with tuned stiffness end springs to predict FMVSS214S full vehicle crush performance. Such models can be solved in minutes and hence very useful for DFSS studies during product design. The proposed method can be used to finalize door beam design for identical size of vehicle doors to meet required FMVSS214S crush performance. The paper highlights the door beam end springs tuning for identical size of cars and SUVs. Four vehicles were considered for the study. A single spring F-D (force -displacement) is tuned which correlated well for frond door of all the four vehicles. A separate unique spring F-D was needed which correlated well for rear door of all the 4 vehicles. |
A Research on the Prediction of Door Opening by the Inertia Effect during a Side Impact Crash | The purpose of this study is to develop a dynamic model that can accurately predict the motion of the door handle and counterweight during side impact crash tests. The door locking system, mainly composed of the door outside handle and door latch, is theoretically modeled, and it is assumed that the door outer panel can rotate and translate in all three directions during a side impact crash. Additionally, the numerical results are compared with real crash video footage, and satisfactory qualitative agreement is found. Finally, the simplified test rig that efficiently reflects the real crash test is introduced, and its operation is analyzed. |
Effect of Beam Layout and Specification on Side Door Strength of Passenger Cars: An Experimental Approach to Analyze Its Effect and Contribution to Door Strength. | Risk of injury to occupant in the event of side impact is considerably higher compared to frontal or rear impact as the energy absorbing zones at the front and rear of vehicle is high whereas limited space is available to dissipate the impact energy in the event of side impact. In such scenario strength of side door plays an important role in protecting the occupant. Side door beam in door structure contributes significantly towards the lateral stiffness and plays dominant role in limiting the structural intrusion into passenger compartment. Hence it is interesting to understand the effect of beam specification and orientation on side door strength. Since these factors not only affect the strength but also the cost and weight targets, their study and analysis is important with respect to door design This paper showcases the effect of beam layout and its specifications on the overall strength of the door with an experimental approach using physical test. Beams with different specification and orientation were tested and based upon the test results; a co-relation is built with Side door intrusion test as per IS 12009 |
Simulation and Physical Measurement of Seamless Passenger Airbag Door Deployment | Seamless Passenger Airbag Door, which means the seam of the passenger airbag door is not visible to the passenger, is being frequently implemented in the instrument panel because of its good surface appearance. But it is always a challenge to design a robust passenger airbag door with an invisible seam because many kinds of failures are possible during the design, such as cracks of the substrate of instrument panel, hinge failure of airbag door, windshield breakage, etc. Besides the engineering difficulties, the simulation of seamless passenger airbag door deployment is challenging due to three aspects: 1. the simulation method of the early stage airbag deployment (0~20 msec after trigger), 2. the material model of the airbag door pre-weakening line (the invisible seam); and 3. the physical measurement of the reaction load between cushion and door. In this paper, the FPM (Finite Point Method) method in PAM-CRASH??was used to simulate the early stage airbag deployment and the fabric material model was validated by a material sample tensile test. An airbag deployment test was designed to push a mass upwards and the acceleration of the mass was measured. The measured acceleration shows FPM method with the validated fabric material model is capable to give a good prediction of the early stage airbag deployment. The material model of door seam is also presented and validated with a physical test. To measure the reaction load between airbag cushion and door, Flexi-Force??sensors, film-like pressure sensors, were used. To deal with the nonlinear signal output of the sensor in different pressure ranges, a calibration device was developed exclusively for this sensor. After the calibration, 32 Flexi-Force??sensors were put into a seamless passenger airbag door on the IP structure, and then the reaction load between the airbag door and the cushion was measured in its deployment. The action point position of the resultant reaction load, its peak value and duration correlate with the physical tests. Finally, the limitations and future developments are discussed. |
Study of Side Door Intrusion Test Results | With Ever Increasing Vehicle speed and Vehicle concentration on roads the number of accidents is also increasing. Safety and Strength of Vehicle has become a prime focus in Automobile Industry. The endeavor is to make a safe vehicle which would ensure occupants safety during collision. In Automotives, door system strength plays a vital role in defining the vehicle response during accidents. These accidents through, side door intrusion test and dynamic side impact test are simulated in the vehicle development cycle. Strength of the door required to meet these test criteria is dependent on the door beam, reinforcements, beam layout, vehicle construction and materials selected. There is not a fix method for door beam selection and design. Hence, it becomes all the more difficult to design and layout door beam and other reinforcements. In this paper we will discuss, challenges faced in a layout of door beam for a new vehicle program. Limitation in use of CAE analysis for achieving actual results, and design & layout modifications to be carried out to meet side door intrusion criteria effectively. |
Efficient and Light Weight Door Panels for Automobiles | Automobile manufacturers in the developing nations tend to make more and more fuel efficient cars compared to the luxurious type, given to the popularity. Fuel efficiency has a direct relation with the weight of the vehicle. In order to increase the fuel efficiency, body weight has to be decreased. The weight of all door panels comprises about 15% of body weight of the vehicle. Hence, by reducing the weight of the door panels, fuel efficiency of a vehicle can be increased. But, reduction of the weight of the door panels may lead to decrease in the strength of the panels. Therefore, we need to find a method to increase the fuel efficiency by decreasing the weight and maintaining the strength of the door panels. The aim of our study is to increase the performance while decreasing the weight of the door panel assembly. We have used CAE (Computer aided Engineering) as a tool to study and evaluate the performance of doors, with varying thickness and different shapes like beads. We found different methods to strengthen the panels by modifying the shape. It was concluded that reduction in the weight of the door can be done by improving the shape and performance of the door. |
Structure to Assist in the Prevention of Bimetallic Corrosion of Hybrid Doors | The use of low-density materials in body panels is increasing as a measure to reduce the weight of the vehicle body. Honda has developed an aluminum/steel sheet hybrid door that is more effective in reducing weight than an all-aluminum door. Because aluminum was used in the door skin, bimetallic corrosion at the connection between the aluminum and the steel sheets represented an issue. It was possible that the difference in the electrical potential of the two metals might promote corrosion at the connection between the aluminum door skin and the steel sheet door panel, in particular at the lower edge of the door, where rainwater and other moisture tend to accumulate, with the result that the appeal of the exterior of the door might decline. To address this issue, a watertight structure realized through the use of a high-ductility sealer was employed in order to help prevent water from infiltrating to the connection between the metals, and steel sheets with a zinc-aluminum-magnesium alloy coating, highly effective in controlling bimetallic corrosion, were employed in the door panels. This produced rust-resistance specifications for the hybrid door able to maintain durability in market use environments. This paper discusses the effect of the zinc-aluminum-magnesium alloy-coated steel sheets in controlling bimetallic corrosion. |
Finite Element Analysis of Door Closing Effort | The door closing effort is one of the first impressions to customer's mind about the engineering and quality of the vehicle. The door closing force and the minimum door closing speed are two important characteristics for evaluation. But we can obtain these two indices only by experiments and/or subjective assessments. To predict the door closing effort by the simulation method during the design phase, a finite element analysis model is established. The compression load deflection behavior of seals is converted to the parameters of constitutive model of seals by the parameters identification method. Then, the seal resistance force and the minimum door closing speed are calculated. The later correlates very well with the experiment data. |
A Study on the Rattle Index from a Vehicle Door Trim under Audio System Inputs | The sound inside a passenger cabin is composed of many elements, which include irritating noises such as buzzes, squeaks and rattles. Customer perception of buzz, squeak and rattle (BSR) is measured by Things Gone Wrong (TGW), warranty claims and JD Power surveys.1) The Speaker BSR test has been adopted to evaluate and to eliminate rattle noise of a door module while playing sound through the audio system. Subjective listening had been the preferred method for rattle noise detection, due to the sound of the audio system in any measurement. In this paper a quantitative approach for the rattle noise under the speaker test is proposed. The HANIL E-HWA rattle index was developed using a high pass filter, hiss noise reduction filter, SPL data with short time constant, peak value and fluctuation. The high pass filter was adopted to separate the rattle noise from the speaker sound, due to much higher sound pressure level [108 dB(A)] in the latter case. It is then possible to quantify the rattle noise by the HANIL E-HWA rattle index based on the peak values and fluctuations of the SPL data in the speaker BSR test. This article includes test results which show the improved rattle noise detection capability of the HANIL E-HWA rattle index. |
A Method of Designing Automotive Door Glass and Guide Rail based on the Drum Surface | A new method based on the drum surface is proposed to fit the dual-curvature glass. The drum surface is obtained from the automotive body cloud data with the kinematic equation using line element geometry and K-Local-RANSAC algorithm. Then the guide rail curve is obtained by the proportional function method based on the drum curve principle. At last, the motion deviation of the glass is analyzed and the maximum motion deviation is not more than 0.6mm. The results have completely achieved the engineering requirements, which prove that the method of fitting the glass and the guide rail is correct and reasonable. |
Study of Optimizing Sliding Door Efforts and Package Layout | A sliding door is one of the car door systems, which is generally applied to the vans. Compared with swing doors, a sliding door gives comfort to the passengers when they get in or out the car. With an increasing number of the family-scale activities, there followed a huge demand on the vans, which caused growing interests in the convenience technology of the sliding door system. A typical sliding door system has negative effects on the vehicle interior package and the operating effort. Since the door should move backward without touching the car body, the trajectory of the center rail should be a curve. The curve-shaped center rail infiltrates not only the passenger shoulder room, but also the opening flange curve, which results in the interior package loss. Moreover, as the passenger pulls the door outside handle along the normal direction of the door outer skin, the curved rail causes the opening effort loss. In this study, we discuss not only how the curved center rail causes negative effects on the vehicle interior package and the manual operating effort, but also how to effectively improve and optimize the sliding door system. Moreover, we propose a new design concept of a convenient sliding door system. By applying a straight center rail and a latch with a multi-link structure, we were able to decrease the center rail infiltration. Also, the performance of getting on and off the 3rd row was improved, and the manual operating effort was improved about 60%. |
Vehicle Door Inner Frame Part Design with Knowledge-Based Engineering | In this study, a computer-aided design (CAD) geometry system that is linked to each other to create a parametric form of the side rear door?셲 inner frame sheet piece on a passenger vehicle body in a Siemens NX environment was developed. The system was created in the NX CAD environment, using the program?셲 unique product development structure. The system was designed and modified for time-consuming parts. At the end of the study, the parameterized vehicle door geometries worked in the NX environment standardized the design process and accelerated the design works. |
Classification of Contact Forces in Human-Robot Collaborative Manufacturing Environments | This paper presents a machine learning application of the force/torque sensor in a human-robot collaborative manufacturing scenario. The purpose is to simplify the programming for physical interactions between the human operators and industrial robots in a hybrid manufacturing cell which combines several robotic applications, such as parts manipulation, assembly, sealing and painting, etc. A multiclass classifier using Light Gradient Boosting Machine (LightGBM) is first introduced in a robotic application for discriminating five different contact states w.r.t. the force/torque data. A systematic approach to train machine-learning based classifiers is presented, thus opens a door for enabling LightGBM with robotic data process. The total task time is reduced largely because force transitions can be detected on-the-fly. Experiments on an ABB force sensor and an industrial robot demonstrate the feasibility of the proposed method. |
Novel Glass Laminates for Improved Acoustic Performance | Noise, Vibration, and Harshness (NVH) performance of vehicles is an all-encompassing study of hearing and feeling vibration as it relates to end user experience. The collection of glass in a vehicle can represent a large surface area, and can have a significant effect on NVH performance. Some of the most important glazing positions in relationship to the driver are the front doors, due to the proximity to the driver. Novel glass laminate constructions can provide acoustic improvement for these body positions over typically used standard glazings. The performance of these constructions will be discussed in terms of: acoustics, glass closing and door slam survivability, and solar performance. |
Research on Intelligent Layout of Door Hinge Based on CATIA CAA | As one of the most important auto-body moving parts, door hinge is the key point of door design and its accessories arrangement, also the premise of the door kinematic analysis. We proposed an effective layout procedure for door hinge and developed an intelligent system on CATIA CAA platform to execute it. One toolbar and five function modules are constructed - Axis Arrangement, Section, Parting Line, Kinematic, Hinge Database. This system integrated geometrical algorithms, automatically calculate the minimum clearances between doors, fender and hinges on sections to judge if the layout is feasible. As the sizes of the clearances are set to 0s, the feasible layout regions and extreme start/end points are shown in parts window, which help the engineer to check the parting line and design a new one. Our system successfully implemented the functions of five modules for the layout of door hinge axis and parting line based on a door hinge database. An instance is carried out and the result shows that our system has great feasibility and validity to arrange the door hinge and shorten the design periods. |
Door Closing Sound Quality Methodology - Airborne and Structural Path Contributions | The intent of this paper is to document comprehensive test-based approach to analyze the door-closing event and associated sound using structural and acoustic loads developed during the event. This study looks into the door-closing phenomenon from the structural interaction point of view between the door and the body of the vehicle. The study primarily focuses on distributing the door and body interaction as discrete multiple structural and acoustic phenomena. It also emphasizes on the structural and acoustic loads developed by the discretized interactions at the interfaces between the door and the body frame. These interfaces were treated to be the load paths from the door to the body. The equivalent structural and acoustic loads were calculated indirectly using the well-known Transfer Path Analysis (TPA) methodology for structural loads and the Acoustic Source Quantification (ASQ) methodology for acoustic loads. Considering the transient nature of the door-closing event, a time domain TPA methodology was also developed to study the loads being developed between the latch, the striker and the different interfaces of the door frame to the body structure. Similarly the equivalent acoustic loads were developed at the interfaces between the door frame and the body. Computed time domain and frequency domain loads were used to perform a partial contribution analysis from different paths and identify the contribution of the structural and acoustic loads and paths on the target response at the center of the operator's ear (COE) located the outside of the vehicle. |
Five Bonding Techniques of Side Door Trim Insert Skin Decoration | Interiors of past vehicles were created to satisfy specific functions with appearance being a secondary consideration, but in the present & future market with ever increasing vehicle luxury, decoration of vehicle has become a prime focus in automobile industry along with the safety & economy. Automotive interiors have evolved over the years from a collection of trims covering bare sheet metal panels to add quality & richness of interior cabin, ultimately delivering greater value to customers. One such area in interiors is Side door trims serving the dual purpose of functionality and creating a pleasing environment too. The aesthetic appeal to the Side door trim is added usually through a Door trim insert having a decorative skin pasted on to the plastic base. And the selection of pasting technique for pasting decorative film on to the plastic base insert is a challenge for an automotive interior designer. The objective of this paper will be to review technologies available for manufacturing Door trim inserts with decorative skins, and discuss a direction toward selecting an appropriate pasting technique with cost effectiveness. In automotive industry, for Side door trim insert decoration, five bonding techniques are used ranging from Adhesive pasting, Thermo compression molding using natural fiber reinforced PP, Pressure lamination, Kimikomi, and Low pressure injection molding, all these will be discussed in this paper. A brief synopsis of the advantages and disadvantages of each process including cost effectiveness, design considerations, shape & complexity of Door trim inserts, Door trim insert skin types & their physical property requirements, process considerations and its testing methods are covered. In addition to this, the necessary tooling investment will also be discussed in this paper. |
A Component Test Methodology for Simulation of Full-Vehicle Side Impact Dummy Abdomen Responses for Door Trim Evaluation | Described in this paper is a component test methodology to evaluate the door trim armrest performance in an Insurance Institute for Highway Safety (IIHS) side impact test and to predict the SID-IIs abdomen injury metrics (rib deflection, deflection rate and V*C). The test methodology consisted of a sub-assembly of two SID-IIs abdomen ribs with spine box, mounted on a linear bearing and allowed to translate in the direction of impact. The spine box with the assembly of two abdominal ribs was rigidly attached to the sliding test fixture, and is stationary at the start of the test. The door trim armrest was mounted on the impactor, which was prescribed the door velocity profile obtained from full-vehicle test. The location and orientation of the armrest relative to the dummy abdomen ribs was maintained the same as in the full-vehicle test. An aluminum honeycomb of a pre-determined crush strength and cross-sectional area attached to the base of the assembly of two abdominal ribs was used to simulate the lumbar shear force, to capture the effect of lower torso loading on the upper torso. The test methodology was developed and validated to a full-vehicle test and the sensitivity of the methodology to different armrest designs was also evaluated. The results show good correlation to full-vehicle test, thus indicating that this component test methodology has good potential to evaluate different armrest design alternatives across various vehicle programs. |
An Experimental Study on Flow Pattern of Door Trim Speaker Grille Shape | Recently the automotive industry has focused on reducing product development time to correspond with the customer's demands. Especially when quickly changed. The decreased product development time shortens the quality assurance period. It makes difficult to guarantee the quality of the products. The improved quality assurance is required so that customer's expectations are actually higher quality than in the past. Most automotive interior parts are manufactured by using plastic. It is very sensitive to focus on quality, because it is exposed to a passenger's sight. So automotive interior companies make full use of injection molding CAE in an effective ways to reduce costs and reduce elements of poor quality. This paper suggests a methodology that improves reliability for injection molding analysis in grille shapes of door trim. And it involves an experimental analysis of flow pattern in speaker grille shapes. To analyze it, use an authentic mold of speaker grilles in door trim and Mold flow software. |
CAE Simulation of Door Sag/Set Using Subsystem Level Approach | The performance of door assembly is very significant for the vehicle design and door sag/set is one of the important attribute for design of door assembly. This paper provides an overview of conventional approach for door sag/set study based on door-hinge-BIW assembly (system level approach) and its limitation over new approach based on subassembly (subsystem level approach). The door sag/set simulation at system level is the most common approach adopted across auto industry. This approach evaluates only structural adequacy of door assembly system for sag load. To find key contributor for door sagging is always been time consuming task with conventional approach thus there is a delay in providing design enablers to meet the design target. New approach of door sag/set at ?쐓ubsystem level??evaluates the structural stiffness contribution of individual subsystem. It support for setting up the target at subsystem level, which integrate and regulate the system level performance. This approach is also useful for generating the design enablers and for optimization of door-hinge-BIW assembly with higher reliability. The commercial software ?쏛BAQUS STANDARD??is used as FE solver to simulate the door sag/set by both the approaches with application of material, geometrical and contact nonlinearities. |
Experimental Approach to Improve the Door Slam Noise Quality in Utility Vehicles | The customer perception about the door slam noise and its feel would indicate the brand image of the car. In this paper the authors have made an effort to improve the door slam noise quality of the vehicle, which is currently in production. This paper describes the probable areas in the door to improve the slam noise quality by attempting modifications in the door design factors, such as door alignments, door panel stiffness, door trims, window glass rattle, latch striker alignment, door seals, air extractor. Since the door closing event is a transient phenomenon, it requires special tools such as wavelet transforms, Zwicker loudness to understand the slam events precisely. Subjective jury evaluations have been conducted to understand the effect of these modifications and rank the modifications based on their contributions to the door slam quality. |
French Door Open/Close Durability Evaluation by Multibody Dynamics Method | A method including Multi-Body Dynamics (MBD) and fatigue assessment process with modal approach was developed to predict Light Commercial Van (LCV) Rear French Doors open/close durability performance during early design stage to improve test detect ability. The nonlinear properties of joints, such as those on bolted housings or spot welds sheets and hem flange areas, can substantially influence the local and global results of a dynamic simulation. The Modal approach considers joint contact, by way of Joint Interface Modes (JIMs) by using Contact Subroutine (MAMBA) to co-simulate with MBD software to improve result quality. One of the main challenges is measuring the dynamic stiffness for the weather strip. A novel test method was used to measure the weather strip dynamic stiffness by conducting an ?쐇n-situ??test. For CAE simulation results, positive feedback was received from design and test engineers. |
Study of the Energetic Influence of Each Component Responsible for Closing the Side Doors | Currently, studies are being developed by automobile engineers about the energy required by the client during the closing door of the car. This paper proposes an analysis of A segment vehicle, four doors, in order to evaluate the influence of each component of the door/body responsible for closing the side doors. Tests will be carried out to demonstrate exactly the contribution of the door sealing, exhaust air valve and the inner cabin air pressure effect, door link, hinges and latch, plus the actual weight of the door during the closing. The results show which are the door/body components most responsible for car door closing movement energy increase and still, where to direct efforts to provide greater comfort for customers. |
Integration and Lightweight Design in Automotive Doors | Future doors require light weight, cost efficient and acoustic optimized solutions. Current steel doors offer only a small range of possibilities in these areas. With the use of aluminum doors the weight will be reduced but production complexity and costs will be increased. A modular door approach supports all of these future demands. Door modules have set milestones for door concepts in the past. Due to technological progress, door modules are more relevant in the current scenario. The use of reinforced plastics allows a high degree of design freedom with high integration of features.[2] In addition to weight reduction of up to 1.5kg per door the complete production process comes leaner with a higher grade of quality. The acoustic performance of a door system can be adjusted for noise reduction and improvement of the sound quality of speakers as illustrated. Functional integration is the key driver of weight and cost reduction |
A Study on Prediction of Door Deformation in High Speed Passenger Vehicle at Cross Wind | In this study, several design factors are considered to predict door deformation. Door deformation is mainly influenced by air flow around A-pillar and door static stiffness. Therefore design factors can be divided into two categories. First, design elements determined by the appearance of a car affect to the air flow around A-pillar. Second, door static stiffness is determined by engineering design parameters. Kriging method is used to predict door deformation by means of the design factors. Door deformation can be successfully predicted with this method. |
Modelling and Simulation of Door Control System | A Door Control System is being used for controlling doors in buses running in urban/suburban areas as a part of safety requirement and to protect the passengers. The opening and closing of the doors will be in logical sequence depending upon the driver input, vehicle speed and the emergency conditions. To achieve this logic the door control system consists of an ECU, pneumatic valves, pressure sensors and switches. To predict the performance of this system under various operating conditions, the entire system is being modeled in one of the commercially available multi-domain physical modeling software employing bond graph technique and lumped system and the performance is predicted. This paper deals with the modeling and simulation of entire Door Control System. |
Investigation of Relation between Sub System Level (Quasi-Static) Side Door Intrusion to Side Collision Test | With the change in the perspective of the Customers towards safer vehicles, most of the Vehicle manufacturers in India are making their vehicles Crash compliant. According to the accidental data collection, Side crashes are second leading cause of death after Frontal crash. Currently sub system level tests are done for evaluating the side impact safety performance of the vehicle. One of such sub system level test is Quasi-static side door intrusion Test. The primary purpose of this testing is to measure the Force-deflection characteristics by intrusion of the impactor into the vehicle. These characteristics are controlled by various door components like door beam, latch & striker, hinge etc. This article studies the relation between Side door intrusion and Side collision, effect of above mentioned components on this relation. A theoretical study is done to study this relationship and it is substantiated with experimental data. |
Study of Sliding Door Closing Speed for a Manually Operated Sliding Door | The door performance of an automobile is gauged not only by its function but also the ?쐄eel??of operating a door which majorly depends upon opening/closing force and closing speed. This feel is in direct relation to the soundness of design and the build quality which the customer experiences even before driving the vehicle. Several studies have been conducted for door open/close performance for a conventional swing door, however little has been done in direction of sliding door. In this paper an analysis of closing speed of manually operated sliding door in purview of various parameters affecting them and their individual and combined contribution at vehicle level is presented. As the closing locus of sliding door is different from a swing door, a special experimental setup is used to measure the closing speed of sliding door. |
MMLV: Door Design and Component Testing | The Multi Material Lightweight Vehicle (MMLV) developed by Magna International and Ford Motor Company is a result of a US Department of Energy project DE-EE0005574. The project demonstrates the lightweighting potential of a five passenger sedan, while maintaining vehicle performance and occupant safety. Prototype vehicles were manufactured and limited full vehicle testing was conducted. The Mach-I vehicle design, comprised of commercially available materials and production processes, achieved a 364kg (23.5%) full vehicle mass reduction, enabling the application of a 1.0-liter three-cylinder engine resulting in a significant environmental benefit and fuel reduction. This paper reviews the mass reduction and structural performance of aluminum, magnesium, and steel components for a lightweight multi material door design for a C/D segment passenger vehicle. Stiffness, durability, and crash requirements are assessed. The structure incorporated aluminum sheet, aluminum extrusion, magnesium high pressure vacuum die casting and steel sheet. The multi material components were assembled using structural adhesive bonding (hem and structure), self-pierce rivets (SPRs), single sided rivets, and bolts. The aluminum extrusion and the magnesium casting in the MMLV door were specifically designed to maximize stiffness, reduce part count and maximize mass reduction. To optimize the strength and weight of the MMLV door, a new aluminum intensive structure was developed. The new structure features a unique architecture that uses a multi-cavity aluminum extrusion joined to stamped sheet reinforcements to provide a direct load path between the hinges and the latch. The new structure also utilizes a high pressure vacuum die cast magnesium casting to create the structure at the base of the A-pillar on the front door to achieve the required structural stiffness while reducing components and maximizing the mass reduction. The ?쐀arn door??architecture of the inner structure of the door allowed for gage optimization of both the inner and outer stampings, the two largest and heaviest components of the assembly. Overall, the design architecture used in the MMLV doors allowed for a mass reduction of 33% through the use of multi material, gage optimization, and multiple forming technologies, while achieving all of the structural requirements. |
Numerical Study of Effect of Material and Orientation on Strength of Side Door Intrusion Beam | Nowadays more and more people are concerned about the safety rating of their vehicle. The safety rating depends on the ability of the car to minimize the injury to the occupants post-crash. Crashworthiness of the vehicle is determined by carrying out various tests such as static and dynamic tests. Side crashes are one of the leading causes of fatal injury following front crashes. Side door strength is dependent on the door components such as latch and striker, hinge, door beam etc. Lateral stiffness is contributed significantly by the side door beam in the door structure. The side door beam limits the side intrusion into passenger compartment. This paper emphasizes the effect of intrusion beam materials and orientation in the side door strength with a numerical approach using ANSYS tool. These factors affect the strength and weight of the door. The simulation study with respect to door design is cost-effective and time-saving. Side door intrusion test as per IS 12009 norms is simulated in the software and are substantiated by the experimental test results of existing literature. |
Vehicle Door Cutline Determination with Mathematical Modelling on CATIA V5 | Door shut-line definition is the first vital step in car body door engineering and depends on the hinge position, hinge shape, manufacturing capabilities and other parameters. In the design process, once the hinge axis definition is finalized door shut-line is defined which should satisfy two major requirements. The requirements are clearance between the door outer surface with its surrounding components (like hinges, fender, other door etc.) and assembly feasibility. Another one is the manufacturability of the proposed design. The above conditions must be checked on different locations of the door as well as w.r.t different openings of the door. The paper presents a mathematical model to determine the door shut-line position with great computational efficiency. This method propounds closure engineer with parameters to define the shut line rather than going for cumbersome manual iterative process. Instead of following an iterative approach to determine a limit for the shut-line, paper presents a mathematical formulation with an implicit equation. An innovative approach to solve implicit equation on CATIA is also discussed which significantly reduces the processing time. This paper inherently discusses a series of challenges which a user faces while determining the door shut-line and provides feasible solutions for those problems. |
CFD-Simulation and Validation of Cabin Pressure during Door Closing Motions | Under the competitive pressure of automotive industry the customer?셲 focus is on a vehicle?셲 quality perception. Side door closing efforts make a considerable share of the overall impression as the doors are the first physical and haptic interface to the customer. Customer?셲 subjective feeling of vehicle quality demands for detailed analysis of each contributor of door closing efforts. Most contributors come from kinematic influences. Beside the losses due to mechanical subsystems like the checkarm, latch or hinge friction one of the biggest impacts originates from the pressure spike that builds up due to air being pushed into the cabin. Subject of this publication is to discuss the dependencies of closing efforts on cabin pressure and air extraction. It demonstrates an approach to simulate the development of the air pressure during door closing motions and the validation of the simulation method with the ?쏣Z-Slam??measurement device. In order to produce a correlation between simulation and reality a simplified model of a vehicle cabin is created. The validation tests are conducted on a physical test rig, built exactly according to the model, and the CFD simulation is done on the CAD model of the rig. In order to show a correlation between the CFD method and the physical test procedure a set of influencing parameters is identified and tested for its impact on the pressure spike. |
An Optimal Design of Vehicle Swing Door Using Metamodeling Techniques | In side-closures??design, mass reduction provides numerous benefits in addition to reduced cost. This paper presents a Meta model based non-linear durability optimization to develop a lightweight structure for vehicle swing door. A surrogate model developed is using Kriging methodology and the thickness of the door components are given as input design variables. Adaptive Multi-Objective Genetic Algorithm (AMGA), a nonlinear optimization technique, is used in this study, to formulate the mass minimization under durability constraints. The optimized swing door design shows the overall mass saving of ~10% over initial design in terms of frame and sag deflection. The present investigation shows better effectiveness and practical applicability to develop the lightweight structure for the vehicle swing door. From the comparative study, Kriging method is found to be more effective in terms of measuring the accuracy, robustness and efficiency of the results than the Radial basis function (RBF). |
Development of the Wireless Power Transfer Technology for a Sliding Door | The sliding door?셲 movement is 3-dimensional unlike the conventional door. So the electric power and signal are exchanged via the long ?쁏ower Cable?? It has a quite complex structure in order to be suitable to connect the vehicle?셲 body and the sliding door even during it?셲 moving. As the result, it is more expensive than conventional door?셲 one and the quality could not be guaranteed easily. In this paper, I have developed new technology which could transfer electric power by ?쁶ireless transfer??in order to resolve the problem from using ?쁏ower cable?? I would propose the proper structure to transfer the electric power at any position of the sliding door without any physical connection. To transfer the electric power which drives the window regulator and the actuators in door, I have applied the ?쁦nductive coupling??system. And in order to decide the engineering properties - such as the dimensions of the core, the values of the electric elements and the frequency of the transferred electricity - a myriad of computer analysis and experiments under various conditions would be implemented. Finally, the optimal solution was figured out and it was validated under the real vehicle?셲 condition. This research would be adopted in various types of the future door system. |
A Study on Door Clips and Their Influence on BSR Performance | Squeak and rattle concerns account for approximately 10% of overall vehicle Things Gone Wrong (TGW) and are major quality concern for automotive OEM?셲. Objectionable door noises are one of the top 10 IQS concerns under any OEM nameplate. Door trim significantly contributes to overall BSR quality perception. Door trim is mounted on door in white using small plastic clips with variable properties that can significantly influence BSR performance. In this paper, the performance of various door clips is evaluated through objective parameters like interface dynamic stiffness and system damping. The methodology involves a simple dynamic system for the evaluation of the performance of a clip design. Transmissibility is calculated from the dynamic response of a mass supported by clip. Parameters such as interface stiffness and system damping are extracted for each clip design. Variation of inner panel thickness is also considered when comparing clip performance. In a second step, clip characteristics are transferred to an equivalent finite element model to predict the response of mass supported by clip. The equivalent clip model is compared with generic clip model for analyzing squeak and rattle simulation in a door assembly. A satisfactory correlation has been achieved between measured and simulated response of clip. Design targets are finally presented for the selection of door clips in the product development process, to avoid rattle issues in door trim assemblies. |
Door Closure Sound Quality Engineering Process | An important factor contributing to a customer?셲 subjective perception of a vehicle, particularly at the point-of-purchase, is the sound created by the passenger doors during closure events. Although these sounds are very short in duration the key systems that control the sounds produced can be highly coupled. Similarly, the necessary efforts required to understand key design criteria affecting the sound can also be highly complex. Within this paper sub-systems affecting the door closure sound are evaluated to understand key structural properties and behaviors toward the contribution to the overall sound produced. This begins with the subjective preferences of typical sounds and the difficulties with both measuring and reproducing these sounds appropriately and leads directly to the target setting and target cascading process. With targets in place, it becomes important to link them with physical measurements of the vehicle and door system to identify the key controlling mechanisms that can be affected through design. The behavior of the door system during a closure event is key for the sound produced and can be studied to understand both the nearfield acoustic field generated as well as the structural vibration patterns. This can be accomplished during a closure event and linked to in-lab assessments that allow for greater repeatability and flexibility. Boundary conditions for the door structure are also relevant to the sound produced, including the transmission of forces into the seals, latch and striker, and bump-stops, as well as understanding the effects from the vehicle interior cavity. Once the key controlling mechanisms affecting the door closure sound quality are understood, it allows for the sound produced to be shaped as desired. This can be accomplished by leveraging analytical modeling efforts, supplemented with necessary test data, to design key components and systems to achieve the desired sound. |
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