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When vehicles share certain information wirelessly via Dedicated Short Range Communications (DSRC), they enable a new layer of electronic vehicle safety that, when needed, can generate warnings to drivers and even initiate automatic preventive actions. Vehicle location and velocity provided by Global Navigation Systems (GNSS), including GPS, are key in allowing vehicle path estimation. GNSS is effective in accurately determining a vehicle's location coordinates in most driving environments, but its performance suffers from obstructions in dense urban environments. To combat this, augmentations to GNSS are being contemplated and tested. This testing has been typically done using a reference GNSS system complimented by expensive military-grade inertial sensors, which can still fail to provide adequate reference performance in certain environments.

When vehicles share certain information wirelessly via Dedicated Short Range Communications (DSRC), they enable a new layer of electronic vehicle safety that, when needed, can generate warnings to drivers and even initiate automatic preventive actions. Vehicle location and velocity provided by Global Navigation Systems (GNSS), including GPS, are key in allowing vehicle path estimation. GNSS is effective in accurately determining a vehicle's location coordinates in most driving environments, but its performance suffers from obstructions in dense urban environments. To combat this, augmentations to GNSS are being contemplated and tested. This testing has been typically done using a reference GNSS system complimented by expensive military-grade inertial sensors, which can still fail to provide adequate reference performance in certain environments.

The purpose of this study is to examine compatibility test procedures proposed in the IHRA Vehicle Compatibility Working Group. Various crash tests were conducted with different vehicle weights and stiffness in our previous study, and each of the compatibility problems, namely mass; stiffness and geometric incompatibility were identified in these tests. In order to improve the compatibility, it is necessary to evaluate and control relevant vehicle characteristics of compatibility in test procedures. According to the IHRA study, relevant aspects for compatibility in frontal impact are: Good structural interaction; Frontal stiffness matching; Maintaining passenger compartment integrity; Control the deceleration time histories of impacting cars.

Fuel economy can be increased by reducing running resistance or mechanical drag. Since modern disk brake systems produce mechanical drag, a component-level test method was developed to measure and understand this effect. Measuring brake drag typically requires a vehicle test on a chassis dynamometer, and an engineer must distinguish brake drag from other sources of drag (e.g., tire, wheel bearing, transmission, and others). This method often generates brake drag data that lacks in resolution, accuracy, and repeatability. Alternatively, a new method of measuring drag on a traditional brake dynamometer has been developed that yields statistically relevant and repeatable results. To accurately measure brake drag on a brake dynamometer, pad temperature, wheel bearing temperature, and caliper experience pressure need to be controlled. Also, depending on the type of wheel bearing used, a correction factor for bearing drag may be needed.

In recent years, the slip lock-up mechanism has been adopted widely, because of its fuel efficiency and its ability to improve NVH. This necessitates that the automatic transmission fluid (ATF) used in automatic transmissions with slip lock-up clutches requires anti-shudder performance characteristics. The test methods used to evaluate the anti-shudder performance of an ATF can be classified roughly into two types. One is specified to measure whether a μ-V slope of the ATF is positive or negative, the other is the evaluation of the shudder occurrence in the practical vehicle. The former are μ-V property tests from MERCON® V, ATF+4®, and JASO M349-98, the latter is the vehicle test from DEXRON®-III. Additionally, in the evaluation of the μ-V property, there are two tests using the modified SAE No.2 friction machine and the modified low velocity friction apparatus (LVFA).

Mode management is an essential part of the design process for NVH performance. System resonances must be sufficiently separated to minimize interaction from source inputs and each other [1]. Such resonances are typically determined through experimental modal testing conducted in a lab environment under controlled and repeatable conditions. Global vehicle and suspension system response demonstrate soft nonlinear behavior, however. Their resonant frequencies may thus decrease under on-road input not reproducible in a lab environment. Subsequently, mode management charts derived from lab testing may not be representative of the vehicle's on-road dynamic response. This paper presents modal model determination methodologies, and examines suspension system and vehicle global dynamic response under lab modal test and operating conditions. Vehicle suspension modes measured under static and dynamic (rolling) conditions will be compared.

Loads generated during assembly may cause significant stress levels in components. Under test conditions, these stresses alter the mean stress which in turn, alters the fatigue life and critical stress area of the components as well. This paper describes the Finite Element Analysis (FEA) procedure to evaluate behavior of a cast aluminum wheel subjected to the rotary fatigue test condition as specified in the SAE test procedure (SAE J328 JUN94). Fatigue life of the wheel is determined using the S-N approach for a constant reversed loading condition. In addition, fatigue life predictions with and without clamp loads are compared. It is concluded that the inclusion of clamp load is necessary for better prediction of the critical stress areas and fatigue life of the wheel.

An impact test procedure with a legform addressing lower limb injuries in car-pedestrian accidents has been proposed by EEVC/WG17. Although a high frequency of lower limb fractures is observed in recent accident data, this test procedure assesses knee injuries with a focus on trauma to the ligamentous structures. The goal of this study is to establish a methodology to understand injury mechanisms of both ligamentous damages and bone fractures in car-pedestrian accidents. A finite element (FE) model of the human lower limb was developed using PAM-CRASH™. The commercially available H-Dummy™ lower limb model developed by Nihon ESI for a seated position was modified to represent the standing posture of pedestrians. Mechanical properties for both bony structures and knee ligaments were determined from our extensive literature survey, and were carefully implemented in the model considering their strain rate dependency in order to simulate the dynamic response of the lower limb accurately.

The 2-Stroke Engine Oil Subcommittee of the JSAE has developed the following five JASO (Japan Automobile Standards Organization) 2-Stroke Gasoline Engine Oil Quality Standards for motorcycle, utility and outboard engines: 1) JASO M340-92 Lubricity test procedure for evaluating two stroke gasoline engine oils 2) JASO M341-92 Detergency test procedure for evaluating two stroke gasoline engine oils 3) JASO M342-92 Smoke test procedure for evaluating two stroke gasoline engine oils 4) JASO M343-92 Exhaust system blocking test procedure for evaluating two stroke gasoline engine oils 5) JASO M345-93 Two stroke gasoline engine oils These standards consist of four kinds of engine test procedure and a classification system which includes three physico chemical properties of an oil.

Laboratory accelerated weathering test methods, such as SAE J2527 and JIS D 0205, are used to predict long term durability in the development and approval of automotive coatings. However, recent studies have shown that these methods are deficient with respect to spectral match to sunlight, simulation of water, and temperature profile. These deficiencies can limit the confidence of the laboratory accelerated test, and as a result the user needs to rely more heavily on long term natural exposure results. To increase the confidence of laboratory accelerated weathering testing, a new xenon arc light source filter and test protocol were investigated. Through a combination of natural weathering studies and prototype method testing, an improved accelerated weathering test cycle has been developed.

Determination of an engine's inertial properties is critical during vehicle dynamic analysis and the early stages of engine mounting system design. Traditionally, the inertia tensor can be determined by torsional pendulum method with a reasonable precision, while the center of gravity can be determined by placing it in a stable position on three scales with less accuracy. Other common experimental approaches include the use of frequency response functions. The difficulty of this method is to align the directions of the transducers mounted on various positions on the engine. In this paper, an experimental method to estimate an engine's inertia tensor and center of gravity is presented. The method utilizes the traditional torsional pendulum method, but with additional measurement data. With this method, the inertia tensor and center of gravity are estimated in a least squares sense.

This paper investigates test procedures for vehicle frontal crash compatibility. Both Full Width Deformable Barrier (FWDB) tests and Moving Deformable Barrier (MDB) tests were studied to assess relevant factors of compatibility issues. The FWDB test with load cells was examined to evaluate the stiffness and interaction areas of vehicles (sometimes referred to as the “aggressivity” of vehicles). Compatibility metrics were computed using barrier load cell data and the output from the FWDB test was compared with that from the Full Width Rigid Barrier (FWRB) test. Since the results obtained from these two full width tests were considerably different, a full frontal vehicle-to-vehicle test was carried out to identify structural deformation modes. The results indicated that similar deformation modes were observed between the vehicle-to-vehicle test and the FWDB test.

This paper presents a validation method for indoor testing of a passenger car suspension. A study was done to design a supporting modular structure with comparable inertances with respect to a vehicle's actual suspension and body connection points. For the indoor test, the rear axle is positioned on a rotating drum. The suspension system is excited as the wheel passes over cleats fixed on the drum and transient wheel motions are recorded. The indoor test rig outputs (i.e., wheel and chassis accelerations) were compared with experimental data measured on an actual vehicle running at different speeds on the same set of cleats along a flat road. The comparison results validate the indoor testing method. The forces and moments acting at each suspension and chassis connection point were measured with a set of patented six-axis load cells. The forces, moments, wheel and subframe accelerations were measured up to 120 Hz.

The National Highway Traffic Safety Administration (NHTSA) has developed moving deformable barriers for vehicle crash test procedures to assess vehicle and occupant response in partial overlap vehicle crashes. For this paper, based on the NHTSA Oblique Test procedure, a mid-size sedan was tested. The intent of this research was to provide insight into possible design changes to enhance the oblique collision performance of vehicles. The test results predicted high injury risk for BrIC, chest deflection, and the lower extremities. In this particular study, reducing lower extremity injuries has been focused on. Traditionally, lower extremity injuries have been reduced by limiting the intrusion of the lower region of the cabin's toe-board. In this study, it is assumed that increasing the energy absorbed within the engine compartment is more efficient than reinforcing the passenger compartment as a method to reduce lower extremity injuries.

Clarifying the impact of ETBE 8% blended fuel on current Japanese gasoline vehicles, under the Japan Clean Air Program II (JCAPII) we conducted exhaust emission tests, evaporative emission tests, durability tests on the exhaust after-treatment system, cold starting tests, and material immersion tests. ETBE 17% blended fuel was also investigated as a reference. The regulated exhaust emissions (CO, HC, and NOx) didn't increase with any increase of ETBE content in the fuel. In durability tests, no noticeable increase of exhaust emission after 40,000km was observed. In evaporative emissions tests, HSL (Hot Soak Loss) and DBL (Diurnal Breathing Loss) didn't increase. In cold starting tests, duration of cranking using ETBE 8% fuel was similar to that of ETBE 0%. In the material immersion tests, no influence of ETBE on these material properties was observed.

In automotive industry, all passenger vehicles are treated with damping materials to reduce structure borne noise. The effectiveness of damping treatments depends upon design parameters such as choice of damping materials, locations and size of the treatment. This paper proposes a CAE (Computer Aided Engineering) methodology based on finite element analysis to optimize damping treatments. The developed method uses modal strain-energy information of bare structural panels to identify flexible regions, which in turn facilitates optimization of damping treatments with respect to location and size. The efficacy of the method is demonstrated by optimizing damping treatment for a full-size pick-up truck. Moreover, simulated road noise performances of the truck with and without damping treatments are compared, which show the benefits of applying damping treatment.

The International Lubricant Standardization and Approval Committee (ILSAC) ATF subcommittee members have compared the two oxidation bench test methods, Aluminum Beaker Oxidation Test (ABOT) and Indiana Stirring Oxidation Stability Test (ISOT), using a number of factory-fill and service-fill ATFs obtained in Japan and in the US. In many cases, the ATFs were more severely oxidized after the ABOT procedure than after the same duration of the ISOT procedure. The relative severity of these two tests was influenced by the composition of the ATFs. The bench test oxidation data were compared with the transmission and the vehicle oxidation test data.

Since being commissioned in 2001, the aero-acoustic wind tunnel at DTF, Wind Tunnel 8 (WT8) has been used to conduct a wide variety of tests. In 2003 alone, over 5250 hours of aerodynamic and aero-acoustic testing were run on over 2000 test articles, including commercial cars, trucks and racing vehicles. Additionally, more unique test articles such as solar cars, motorcycles, Olympic sleds, and others have also been recently tested. The demand for WT8 is driven by the fact that it is among the quietest wind tunnels in the world and one of a very small number of facilities that combines aerodynamic, aero-acoustic, and climatic capabilities in one facility. To enhance WT8's ability to meet the ever-increasing demands of the testing community, and the Motorsports community specifically, an effort was recently initiated to optimize and document the repeatability of aerodynamic force measurements in this tunnel.

The objective of this paper is to investigate the effect of stamping process on oil canning and dent resistance performances of an automotive roof panel. Finite element analysis of stamping processes was carried out using LS-Dyna to obtain thickness and plastic strain distributions under various forming conditions. The forming results were mapped onto the roof model by an in-house developed mapping code. A displacement control approach using an implicit FEM code ABAQUS/Standard was employed for oil canning and denting analysis. An Auto/Steel Partnership Standardized Test Procedure for Dent Resistance was employed to establish the analysis model and to determine the dent and oil canning loads. The results indicate that stamping has a positive effect on dent resistance and a negative effect on oil canning performance. As forming strains increase, dent resistance increases while the oil canning load decreases.

Most products are designed to operate for a long period of time, and in such case, life testing is a relatively lengthy procedure. Lengthy tests tend to be expensive and the results become available too late to be of much use. To reduce the experimental cost significantly and provide an efficient tool to assess the life distribution for highly reliable product, a step-stress accelerated test (SSAT) was developed. An example of a rear suspension aft lateral link is used to validate the SSAT method.