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A test program was conducted to characterize the impact response of an experimental 2-ply windshield construction with a polyurethane (PUR) plastic inner layer. Windshield impact tests were conducted using a linear impactor test facility. Principle among the findings was that the impact response of prototype PUR 2-ply windshields does not differ that significantly from that of baseline 3-ply HPR (High Penetration Resistance) windshields for the subcompact vehicle geometry tested. However, the impact responses of both PUR 2-ply and 3-ply HPR subcompact vehicle windshields were found to be highly variable. Average performance of either construction could thus be enhanced if ways could be found (and then implemented) to reduce this variability.

The environment is one of the most important issues currently facing the world and the automobile industry is required to respond with eco-cars. To meet this requirement, the hybrid vehicle is one of the most optimal solutions. The hybrid system automatically stops engine idling (idling stop), or stops the engine during deceleration to recover energy. The engine stop however creates a problem concerning the vehicle's climate control system. Because the conventional climate control system incorporates a compressor driven by engine belt, there is almost no cooling performance while the engine is stopped. Until now, when a driver needed more cooling comfort the engine has been switched back on as a compromise measure. To realize cabin comfort that is consistent with fuel saving, a 2-way driven compressor has been developed that can be driven both by engine belt while the engine is running and by electric motor when the engine is stopped.

High frequency wind noise caused by turbulent flow around the front pillars of a vehicle is an important factor for customer perception of ride comfort. In order to reduce undesirable interior wind noise during vehicle development process, a calculation and visualization method for exterior wind noise with an acceptable computational cost and adequate accuracy is required. In this paper an index for prediction of the strength of exterior wind noise, referred to as Exterior Noise Power (ENP), is developed based on an assumption that the acoustic power of exterior wind noise can be approximated by the far field acoustic power radiated from vehicle surface. Using the well-known Curle’s equation, ENP can be represented as a surface integral of an acoustic intensity distribution, referred to as Exterior Noise Power Distribution (ENPD). ENPD is estimated from turbulent surface pressure fluctuation and mean convective velocity in the vicinity of the vehicle surface.

As part of the International Lubricant Standardization and Approval Committee's (ILSAC) goal of developing a global automatic transmission fluid (ATF) specification, members have been evaluating test methods that are currently used by various automotive manufacturers for qualifying ATF for use in their respective transmissions. This report deals with comparing test methods used for determining torque capacity in friction systems (shifting clutches). Three test methods were compared, the Plate Friction Test from the General Motors DEXRON®-III Specification, the Friction Durability Test from the Ford MERCON® Specification, and the Japanese Automotive Manufacturers Association Friction Test - JASO Method 348-95. Eight different fluids were evaluated. Friction parameters used in the comparison were breakaway friction, dynamic friction torque at midpoint and the end of engagement, and the ratio of end torque to midpoint torque.

This paper examines the potential use of diamond-like carbon (DLC) on aluminum alloy pistons of internal combustion engines. Our approach is to apply a DLC coating on the piston running against an aluminum-390 bore thus eliminating the iron liners in a standard piston/bore system. Experimental data, using a pin-on-disk tribometer under unlubricated test conditions, indicate that the performance of the DLC coating against aluminum 390 exhibits superior friction resistance compared to aluminum-390 against cast iron; the latter material couple representing the materials currently being used in production for the piston/bore application. Moreover, by thermally cycling the DLC coatings we show that improved friction and wear properties can he maintained to temperatures as high as 400°C.

A new material recycling technology for crosslinked rubber was developed using the continuous reactive processing method. In this process of producing reclaimed rubber, breakage of crosslinking points in the crosslinked rubber occurs selectively under the controls of shear stress, reaction temperature, and internal pressure in a modular screw type reactor. Deodorization during the process has also become possible by a newly developed method. The reclaimed rubber obtained from rubber waste generated from both automobile manufacturing products and post-consumer products shows excellent mechanical properties applicable to new rubber compounds. Furthermore, an enhanced rubber recycling process for producing thermoplastic elastomer (TPE) based on rubber waste has been established. The obtained TPE exhibits highly recoverable rubber elasticity and mechanical properties comparable to commercial TPE.

In this study, a new practical design method (tool) for engine sound quality in a car interior is proposed. The tool can automatically create the target interior sound using the psychoacoustic index ‘powerfulness’ based on subjective tests. Moreover, it can calculate the intake noise characteristic to create the target interior sound and select the suitable intake specification from the prepared database. By using this method sound engineering can be easily and effectively carried out without manufacturing an experimental car.

An efficient light weight 425 Watts charging system was developed and built to meet the requirements of a 12-cylinder engine for racing application. The new system consists of a permanent magnet (PM) alternator with MAGNEQUENCH (MQ3) magnets and a high frequency switching regulator to regulate the output voltage over the engine speed range of 2,000-12,000 rpm. The system has been tested for 75% overall efficiency as compared to 38% for the present system over most of the speed range. Excellent dynamic response (less than 1 ms) has been measured, which allows the alternator to support pulsed loads, even if the battery is disconnected during operation. The new system weighs 3.73 kg vs 5.4 kg of the existing system.

A new 4.0 liter V8 engine, 1UZ-FE, has been developed for the luxury sedan, LEXUS LS400. The engine has 4 camshafts and 32 valves, and weighs only 195 kg (430 lbs) having many light alloy components and carefully designed configurations. The appropriate engine displacement and high technology adopted throughout from design to manufacturing process enable the LS400 to run powerfully with excellent fuel economy and a pleasant sounds. It develops 250HP at 5600 rpm and 260ft-lbs of torque at 4400 rpm, and its fuel economy figure, well exceeds the EPA's tax charge level of 22.5mpg. These figures have been achieved through the newest technologies applied to every part of the design, such as: Well studied intake and exhaust systems, centrally located spark plug in the TOYOTA original four-valve combustion chamber, which has a narrow valve including angle, and low friction components like aluminum alloy valve lifters and well balanced moving parts.

Merging a CAE shape optimization system and a concept Taguchi method SN-ratio index, a robustness-focused automated shape optimization method has been developed. Applying this method to diesel intake ports, with mold position tolerance set as the error factor, SN-ratio was defined for swirl stability. As a result of the optimization provided by a multi-objective genetic algorithm, simultaneous improvement of flux, swirl rotation and SN ratio was achieved.

Statistical Energy Analysis (SEA) is a promising tool for developing an efficient sound package design for reducing airborne interior noise at high frequencies. The optimal sound package, however, is not directly predicted by using the SEA vehicle model alone and therefore requires parametric studies of sound package configurations. This paper describes an effective method for using SEA modeling to achieve the desired interior noise level targets. A mathematical model, expressed by one equation, is derived on the assumption that the directions of the power flows are known in the SEA model. This equation describes the relationship between sound package properties and the resulting interior noise level. Using the relationship between weight and performance of sound package, an efficient configuration can be determined. The predicted sound pressure level of the vehicle interior with the optimized sound package correlated well to the experimental data for the case presented in this paper.

Many efforts have been made to understand the mechanism of whiplash injury. Recently, the cervical facet joint capsules have been focused on as a potential site of injury. An experimental approach has been taken to analyze the vertebral motion and to estimate joint capsule stretch that was thought to be a potential cause of pain. The purpose of this study is to analyze the kinematics of the cervical facet joint using a human FE model in order to better understand the injury mechanism. The Total Human Model for Safety (THUMS) was used to visually analyze the local and global kinematics of the spine. Soft tissues in the neck were newly modeled and introduced into THUMS for estimating the loading level in rear impacts. The model was first validated against human test data in the literature by comparing vertebrae motion as well as head and neck responses. Joint capsule strain was estimated from a maximum principal strain output from the elements representing the capsule tissues.

This paper analyzed the mechanisms of injury in high speed, right-lateral impacts of stock car auto racing, and interaction of the occupant and the seat system for the purpose of reducing the risk of injury, primarily rib fractures. Many safety improvements have been made to stock car racing recently, including the Head and Neck Support devices (HANS®), the 6-point restraint harnesses, and the implementation of the SAFER Barrier. These improvements have contributed greatly to mitigating injury during the race crash event. However, there is still potential to improve the seat structure and the understanding of the interaction between the driver and the seat in the continuation of making racing safety improvements. This is particularly true in the case of right-lateral impacts where the primary interaction is between the seat supports and the driver and where the chest is the primary region of injury.

This paper describes development of a numerical simulation method for the FMVSS 201 testing. This method considers not only deformation but also fracture of plastic materials. a simplified calculation method for predicting the load during impact of absorbing plastic materials was introduced from the numerical simulation results. By applying this simplified calculator method trial and error in development would be reduced.

In the early stages of vehicle development, it is important for decision makers to understand a feasible constraint region that satisfies all system level requirements. The purpose of this paper is to propose a target cascading method to solve for a feasible design region which satisfies all constraints of the system based on model based simulation. In this method, the feasible design region is explored by using both global optimization methods and active learning techniques. In optimization problems, the inverse problem for understanding feasibility for specific designs is defined and solved. To determine the objective functions of the inverse problem, an index representing the achievement level of constraints from system requirements is introduced. To predict feasible regions in the specific design space, a surrogate model of minimized values of the index is trained by using a kriging model.

ACuZinc™ 5, a GM-patented, high-performance ternary zinc-copper-aluminum alloy which is suitable for manufacturing net shape die castings, plays a vital role in the success of new automotive parts and systems. The new parts were designed to meet the auto industry's higher load and safety specifications. The superior mechanical properties of ACuZinc™ make it suitable for structural applications where commercial zinc die casting alloys have been found to be inadequate. From a business viewpoint, ACuZinc™ can help in penetrating new markets by competing for cast iron, powder metal and brass applications. ACuZinc is a registered GM trademark.

Reductions of hardware costs as well as implementations of new innovative functions are the main drivers of today's automotive electronics. Indeed more and more resources are spent on adapting existing solutions to different environments. At the same time, due to the increasing number of networked components, a level of complexity has been reached which is difficult to handle using traditional development processes. The automotive industry addresses this problem through a paradigm shift from a hardware-, component-driven to a requirement- and function-driven development process, and a stringent standardization of infrastructure elements. One central standardization initiative is the AUTomotive Open System ARchitecture (AUTOSAR). AUTOSAR was founded in 2003 by major OEMs and Tier1 suppliers and now includes a large number of automotive, electronics, semiconductor, hard- and software companies.

Knock in spark-ignition (SI) engines has been a subject of many research efforts and its relationship with high efficiency operating conditions keeps it a contemporary issue as engine technologies push classical limits. Despite this long history of research, literature is lacking coherent and generalized descriptions of how knock is affected by changes in the full cylinder temperature field, residence time (engine speed), and air/fuel ratio. In this work, two dimensionless numbers are applied to fully 3D SI conditions. First, the characteristic time of autoignition (ignition delay) is compared against the characteristic time of end-gas deflagration, which was used to predict knocking propensity. Second, the temperature gradient of the end-gas is compared against a critical detonation-based temperature gradient, which predicts the knock intensity.

In real-world automotive control, there are many constraints to be considered. In order to explicitly treat the constraints, we introduce a model-prediction-based algorithm called a reference governor (RG). The RG generates modified references so that predicted future variables in a closed-loop system satisfy their constraints. One merit of introducing the RG is that effort required in control development and calibration would be reduced. In the preceding research work by Nakada et al., only a single reference case was considered. However, it is difficult to extend the previous work to more complicated systems with multiple references such as the air path control of a diesel engine due to interference between the boosting and exhaust gas recirculation (EGR) systems. Moreover, in the air path control, multiple constraints need to be considered to ensure hardware limits. Hence, it is quite beneficial to cultivate RG methodologies to deal with multiple references and constraints.

A numerical model is presented that is capable of isolating and quantifying the heat flux from the gas within the bag to the air bag fabric due to internal surface convection during the inflator discharge period of an air bag deployment. The model is also capable of predicting the volume averaged fabric temperatures during the air bag deployment period. Implementation of the model into an air bag deployment code, namely Inflator Simulation Program (ISP), is presented along with the simulation results for typical inflators. The predicted effect of the heat loss from the bag gas to the fabric on the internal bag gas temperature and pressure and the resulting bulk fabric temperature as a function of fabric parameters and the inflator exit gas properties are presented for both permeable and impermeable air bag fabrics.