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This paper describes the porous materials FE modeling scheme inside vehicle cabin using measured acoustic impedances to reduce the size of the matrices of the FE model while keeping the accuracy. The technique of measuring acoustic impedance using PU probe in a free field is introduced. Next, the surface acoustic impedance of the seat by the side of front is measured using this technique. And the vehicle cabin acoustic field is modeled by FEM using the measured surface acoustic impedance. For the accuracy verification of this model, the acoustic transfer characteristics inside vehicle cabin with and without the front seat are compared with the predicted and the measured transfer function. Moreover, finally the worth of this modeling method is considered.

The survey we are going to present comes from the request to optimize an industrial product pre-assembly chain. Considering the good results we obtained, we’ve built up a methodology and several instruments dedicated to assembly chains where the human presence is still important. The surveyed assembly line was made of an ever-moving conveyor belt with fixed workspaces along it. The requested targets were as follows: Decrease the number of waste products and pre-assembled product fixes by the end of the line; Improve workers’ comfort and efficiency; Improve assembly time by leading the line to the saturation point; Decrease raw materials employ (fixing tapes, adhesives, etc.) There are many aspects to analyze (human factor, layout, equipments, work organization,…) but they are all linked to each other, as well as there are many factors, linked to each other, that can be changed or modified in order to reach the target.

This paper describes the composition of the light-duty automotive fleet leading to 2020 and how it differs from today’s fleet. The most likely scenario for the fleet of 2020 is one where vehicle manufacturers strive to achieve the mandatory regulatory requirements at minimum investment and cost. Simultaneous achievement of multiple regulatory requirements with minimum investment and cost is actually just an optimization problem. What makes this particular optimization especially difficult is that California Air Resources Board (CARB), the National Highway Traffic Security Administration (NHTSA), and potentially the Environmental Protection Agency (EPA) have all chosen different standards and even different metrics that are inextricably linked to fuel efficiency but place different demands on the fleet and even separately on cars and trucks.

Forward Collision Warning (FCW) systems are intended to alert drivers when they may be at risk of a rear-end crash with a vehicle directly ahead unless they take immediate action. A forward collision visual alert (FCVA) is recommended as part of a multi-modality FCW system crash alert approach also including auditory and/or haptic crash alert components. SAE J2400 recommends that a conventional dashboard location shall not be used for the FCVA, since such an alert may distract the driver from the crash threat ahead (instead of helping the driver visually orient toward the crash threat). This research examined the merit of this recommendation by examining the effectiveness of instrument panel, head-up display, and (vehicle-centerline) top-of-dashboard FCVA candidates. In this static on-road study, 49 subjects (20–70 years old) made rapid judgments on the presence and nature of scene changes over two successive forward scene exposures controlled by a visual occlusion window.

In the current study, thermoforming and compression analysis were carried out for the woven composite egg-box panel with the non-orthogonal constitutive material model, which is proposed by Xue et al (Composites: Part A 34 (2003) 183–193). The material model is implemented in commercial engineering software, LS-DYNA, with user subroutine. Xue et al obtained the nonlinear Young’s modulus and shear modulus from the experiment test, but the constant Young’s modulus and shear modulus for fiber are used in this woven composite egg-panel compression analysis for the convenience. Directional properties in non-orthogonal coordinates are detected using the deformation gradient tensor and the material modulus matrix in local coordinate is updated at each time step. After the implemented non-orthogonal constitutive model was verified by performing bias extension test, the egg-box panel simulation was performed.

We define an effective temperature (Teff) as an irradiance-weighted average temperature of a material during weathering. It is the constant temperature that would give the same amount of damage as the sample sustains during natural cycling and serves as a benchmark for predicting lifetimes. It is weakly dependant on the activation energy (Ea) of the degradation process. The annual effective ambient and black panel temperatures at an Arizona test site were 30° and 42°C, respectively, for Ea = 4–7 kcal/mol. Privacy color polycarbonate minivan sunroof windows had surface Teff = 45–46°C exterior, 54–58°C interior, and 49–52°C exterior blackout surfaces. Maximum recorded temperatures were 73°C, 87°C, and 81°C, respectively.

Automotive simulators offer an immersive environment to operate vehicle systems in a safe and repeatable manner. A fundamental question exists regarding their effectiveness for an identified task. For instance, driving simulators can play a significant role in evaluating vehicle designs, developing safety regulations, supporting human factors engineering research, administering driver training and education, and offering individual entertainment. Some of the driving simulator technology users include automotive manufacturers and suppliers, research laboratories at universities and government agencies, driver education and training programs, and motorsports and racing entertainment venues. In each case, the simulator capabilities and functionality must encompass the expectations of the driver to permit their perception of realistic scenarios for evaluation. This paper investigates three driving simulators in terms of their hardware and software, as well as their applications.

Research has been conducted to use an interconnection inverter for a stand-alone generator with an aim to provide a small gas engine cogeneration system with a backup function to serve as an emergency power generator in case of blackout. When a diode rectifier with a large capacitor (hereinafter referred to as a rectifier load) is connected to the interconnection inverter during backup operation, harmonic distortion of the output voltage becomes larger, and in some cases, resulting in miss operation of connected equipment. In order to address this issue, types of connected loads were estimated by focusing on the crest factor of the inverter output current. The crest factor is the value in which the maximum current value is divided by the actual current value.

Air Conditioning systems with reheat reduction based for energy efficiency have generally been implemented with either electronic variable compressors through active stroke control or with fixed displacement compressors through modifying the cycling set point. The present work demonstrates a unique concept of achieving energy efficiency via cycling a pneumatic variable compressor at elevated set points. The energy efficiency of such a system approaches that of an electronic variable but significantly higher than that of a fixed displacement compressor system. The cost of the system, on the other hand, is substantially lower than that of an electronic compressor. Secondary benefits include a softer start than with a fixed compressor and a considerably simpler control scheme than that required by an electronic variable compressor.

We have developed a full virtual engine system prototyping platform with 4-cylinder engine plant model, SH-2A CPU hardware model, and object code level software including OSEK OS. The virtual engine system prototyping platform can run simulation of an engine control system and digital knock detection system including 64-pt FFT computations that provide required high-resolution DSP capability for detection and control. To help the system design, debugging, and evaluation, the virtual system prototyping consists of behavior analyzer which can provide the visualization of useful CPU internal information for control algorithm tuning, RTOS optimization, and CPU architecture development. Thus the co-simulation enables time and cost saving at validation stage as validation can be performed at the design stage before production of actual components.

A recent Gartner Dataquest study predicts that the total worldwide automotive semiconductor market will grow from $20.1 billion in 2007 to $25.9 billion by 2010. The study also predicts that revenue from automotive usage of FPGAs will triple to approximately $312 million during that same period[1]. Many of these FPGAs will be deployed in safety applications such as back-up cameras, lane departure warning systems, blind-spot warning system, and adaptive cruise control. FPGAs will also be deployed in next-generation engine electronics, emissions control, navigation, and entertainment applications. Automotive systems engineers are adept at using Model-Based Design for implementing some of these embedded applications on DSPs and microcontrollers. Many of these engineers are new to FPGA design and waking up to a fragmented workflow that is making it harder to meet time-to-market and cost objectives.

The time reduction of the vehicle design and creation process is an important key to reduce development costs. Modern CAD systems offer a wide range of possibilities, not only in the standard field of mechanical design, but also in terms of creating advanced control mechanisms concerning part and assembly structures. Integrated design strategies include miscellaneous scripting and programming possibilities as well as implemented functions. An efficient application of these features can help to decrease the development time and to manage the growing functional complexity of automotive engineering processes. Continuously increasing product variants and functionalities call for design strategies and methods, which are capable to handle a quick data control and data transfer supporting an efficient geometry creation and evaluation.

This paper described implementation of a selectable one-way clutch in the GM's RWD 6-speed automatic transmission [1] content to replace the current one-way clutch and low/reverse plate clutch. A selectable one-way clutch can hold torque or freewheel in one or both directions depending on the desired operating mode. In this project, it is used as the reaction element to hold torque selectively in 1st gear and reverse. This paper describes hardware design, vehicle implementation, and control of the selectable one-way clutch. In additions, lower parasitic losses due to low/reverse clutch removal is measured and compared with production 6-speed RWD automatic transmissions. Other issues such as durability, cost, packaging, and mass are also addressed. This idea is demonstrated in a 6-speed RWD SUV. Vehicle results show very good static and rolling garage shifts as well as 1-2 upshifts, and 2-1 powered and coast downshifts.

For over 20 years, automotive manufacturers have been harnessing the power of 3D to help create, optimize and produce great vehicles. Product Lifecycle Management (PLM) capabilities such as concurrent development, seamless integration, simultaneous engineering, single source database, and real-time visibility have long been capable within the automotive development process. However, the reality is that these tools have existed for a select few within a corporation, and have never been pervasive to every person involved in a product’s development process. Today, there are certain market drivers requiring more from PLM technology. This includes the fact that companies must drive innovation to survive in today’s increasingly competitive and global auto industry.

In this paper, various micromechanics models based on actual microstructures of DP steels are examined in order to determine the reasonable range of martensite volume fraction where the methodology described in this study can be applied. For this purpose, various micromechanics-based finite element models are first created based on the actual microstructures of DP steels with different martensite volume fractions. These models are, then, used to investigate the influence of ductility of the constituent ferrite and martensite phases and also the influence of voids in the ferrite phase on the overall ductility of DP steels.

The primary coating layer that inhibits salt spray induced corrosion on vehicle bodies is electrocoat. The application of electrocoat involves the electrodeposition of a polymer film on all metallic components of the vehicle body after body construction. Particularly challenging in the electrocoat process is the deposition of the coating in recessed areas of the vehicle due to material and electrical current access constraints to those regions. Currently the verification of correct electrocoat coverage requires the use of costly tear-down prototypes. A simulation tool, called EPD, has been developed that predicts the electrocoat coverage on the full vehicle body. The tool allows engineers to identify areas where there may be issues with electrocoat coverage and to see the effect of vehicle design or process modifications on coverage. A challenge in the development of any simulation tool is computational speed.

Heavy trucks are involved in many accidents every year and Electronic Stability Control (ESC) is viewed as a means to help mitigate this problem. ESC systems are designed to reduce the incidence of single vehicle loss of control, which might lead to rollover or jackknife. As the working details and control strategies of commercially available ESC systems are proprietary, a generic model of an ESC system that mimics the basic logical functionality of commercial systems was developed. This paper deals with the study of the working of a commercial ESC system equipped on an actual tractor trailer vehicle. The particular ESC system found on the test vehicle contained both roll stability control (RSC) and yaw stability control (YSC) features. This work focused on the development of a reliable RSC software model, and the integration of it into a full vehicle simulation (TruckSim) of a heavy truck.

In this paper the integrated control of front and rear active differentials with active front steering is investigated in order to improve dynamics, stability and to reduce the drawbacks of mechanical self-locking differentials. The proposed integrated centralized control feeds back both the yaw rate and the wheel speed measurements to the control inputs which are the front wheel steering angle and the torque transferred by the electronic differentials between the left and the right wheels of both vehicle's axles. The control of the electronic differentials is not only aimed at keeping the wheel speed differences at desired values but it is also integrated with the active steering control (a PI action from the yaw rate error) to produce a yaw moment (also depending on the yaw rate error) which improves handling and stability.

This paper presents a longitudinal control algorithm for an adaptive cruise control (ACC) with collision avoidance (CA) in multiple vehicle traffic situations. The proposed algorithm consists of a multi-target tracking filter, a primary target selection algorithm and an integrated ACC/CA system. The multi-target tracking filter is used to smooth the sensor signal, and makes it possible to apply to a control system. The primary target selection algorithm decides an in-lane target and provides the information to an integrated ACC/CA system in order to drive a subject vehicle smoothly and improve safety in complex traffic situations. Finally, the integrated ACC/CA system computes the desired acceleration. The performance and safety benefits of the multi-vehicle ACC/CA system is investigated via simulations using real data on driving. Simulation results show that the response of multi-vehicle ACC/CA system is more smooth and safer at a change of traffic situations.

Electronic Stability Control (ESC) has the potential of improving yaw stability and reducing the occurrence of a crash when a vehicle experiences a rear tire tread separation. Two instrumented 4-door, RWD SUV’s equipped with ESC were tested to evaluate the effectiveness of their ESC systems on maintaining yaw stability under these circumstances. The test vehicles were evaluated with the tread and outer steel belt removed from the right rear tire. Tests were run with the ESC engaged and then repeated with the ESC disengaged. All runs were completed with the tires inflated to the manufacturer’s recommended pressure. An analysis of the data collected shows that there are significant differences in the steering input required to generate a loss of control response with and without ESC enabled. Results of Sine with Dwell testing demonstrate a significant reduction in vehicle spinout response with the ESC engaged.