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The automotive industry is pursuing significant cost competitive efforts to reduce vehicle weight while maintaining or improving durability and impact performance. One such effort for the body shell structure is the utilization of advanced and ultra high strength steels (AHSS and UHSS) using the existing automotive manufacturing infrastructure. Common AHSS and UHSS steels include Dual Phase (DP), Transformation Induced Plasticity (TRIP), Partial Martensitic (PM) and others. The use of these multiphase high strength steels for impact dependent components has resulted in the need for further material characterization in order to better predict impact performance and guide new material development. This paper addresses the material properties and microstructural influences on impact behavior of advanced and ultra high strength steels through the use of laboratory tests and component level testing.

More than 200 tensile-shear resistance spot welded specimens were produced and tested to analyze the effect of spot weld spacing, weld size, sheet thickness, and adhesive on the ultimate strength of joints made from a mild hot dip galvannealed steel and an unexposed quality hot dip galvannealed 590 MPa minimum tensile strength dual phase steel (DP590). The geometric layout parameters were analyzed by a design of experiment (DOE) approach. The analysis showed that weld size is a primary factor affecting the strength of the joints for a given material. It was also determined that structural adhesive created a large relative strengthening for joints made from the mild steel. Interactions of the geometrical factors are also presented.

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.

The responses of the THOR and the Hybrid-III ATDs to head and neck loading due to a deploying air bag were investigated. Matched pair tests were conducted to compare the responses of the two ATDs under similar loading conditions. The two 50th percentile male ATDs, in the driver as well as the passenger positions, were placed close to the air bag systems, in order to enhance the interaction between the deploying air bag and the chin-neck-jaw regions of the ATDs. Although both ATDs nominally meet the same calibration corridors, they differ significantly in their kinematic and dynamic responses to interaction with a deploying air bag. The difference between the structural designs of the Hybrid-III's and the THOR's neck appears to result in significant differences in the manner in which the loads applied on the head are resisted.

Significant efforts are underway in the automotive industry to reduce vehicle weight while maintaining performance and cost competitiveness. One such effort is the use of advanced high strength steels (AHSS) as the primary body materials method to meet weight targets using the existing automotive manufacturing infrastructure. Issues related to the stamping of AHSS are well known, and significant hurdles still exist for successful implementation. Due to material strength and mechanical behavior, springback is a major hurdle in forming AHSS. While working to form AHSS parts and reduce springback, press shops have encountered a new fracture type. The term shear fracture or local elongation has been loosely used to specify these fractures, which occur at part radii under low strains in multiphase AHSS. These fractures cause design limitations and manufacturing uncertainty.

As the volume and complexity of electronics increases in automobiles, so does the complexity of the electromagnetic relationship between systems. The reliability and functionality of electronic systems in automobiles can be affected by noise sources such as direct current (DC) motors. A typical automobile has 25 to 100+ DC motors performing different tasks. This paper investigates the noise environment due to DC motors found in automobiles and the requirements that automobile manufacturers impose to suppress RF electromagnetic noise and conducted transients.

At one time it was considered imperative to collect high frequency accelerometer data for accurate analysis. As a result current FMVSS regulations and SAE J2570 require the use of accelerometers with damping ratio of 0.05 or less (designated as undamped). This prevents the use of damped accelerometers for regulated channels. Damped accelerometers can provide comparable data and in some cases better data than undamped accelerometers, as long as they meet specific minimum requirements. To collect the most useful data, damped accelerometers should be added to the tool box of transducers used by crash test facilities.

A new family of automotive three-way conversion (TWC) catalyst technologies has been developed using a Precision Metal Addition (PMA) process. Precious metal (PGM) fixation onto the support occurs during the PMA step when the PGM is added to the slurry immediately prior to application to the monolith substrate. PMA slurries can be prepared with high precision and the slurry manufacturing process is greatly simplified. Further, it has been found that with the use of new generation washcoat (WC) materials, the same WC composition can be used for all three PGMs - Pt, Pd & Rh. Negative interactions between Pd and Rh in the same WC layer do not occur, providing advantages over older technologies. Thus, new WC compositions coupled with the PMA process offers precious metal flexibility. This FlexMetal family of catalyst technologies includes single layer Pd-only, Pd/Rh and Pt/Rh and dual layer bi-metal Pd/Rh and Pt/Rh and tri-metal Pt/Pd/Rh.

A finite element model of the Transport Research Laboratory (TRL) honeycomb barrier, which is being proposed for use in vehicle compatibility studies, has been developed for use in LSDYNA. The model employs penalty parameters to enforce continuity between adjacent finite elements of the honeycomb barrier. Results of impact tests with indentors of various shapes and sizes were used to verify the performance of the computational model. Numerical simulations show reasonably good agreement with the test results.

This paper presents a 2D model for frontal vehicle-to-vehicle crashes that can be used for fleet modeling. It presents the derivational details and a preliminary assessment of the model. The model is based on rigid-body collision principles, enhanced adequately to represent energy dissipation and lateral engagement that plays a significant role in oblique frontal vehicle-to-vehicle crashes. The model employs the restitution and the apparent friction in order to represent dissipation and engagement respectively. It employs the impulse ellipse to identify the physical character of the crash, based on the principal directions of impulse. The enhancement of the rigid body collision model with restitution and apparent friction is based on collision simulations that use very simple finite element vehicle representations. The dependence of the restitution and the apparent friction on the incidence angle, the frontal offset, and the mass ratio, as predicted by the 2D model, has been presented.

The Auto/Steel Partnership Corrosion Project Team has completed a perforation corrosion test program consisting of on-vehicle field exposures and various accelerated tests. Steel sheet products with eight combinations of metallic and organic coatings were tested, utilizing a simple crevice coupon design. On-vehicle exposures were conducted in St. John's and Detroit for up to seven years to establish a real-world performance standard. Identical test specimens were exposed to the various accelerated tests, and the results were compared to the real-world standard. This report documents the results of these tests, and compares the accelerated test results (including SAE J2334, GM9540P, Ford APGE, CCT-I, ASTM B117, South Florida Modified Volvo, and Kure Beach (25-meter) exposures) to the on-vehicle tests. The results are compared in terms of five criteria: extent of corrosion, rank order of material performance, degree of correlation, acceleration factor, and control of test environment.

This paper presents an energy relationship between vehicle impact pulses and restraint systems and applies the relationship to formulations of response factors for linear and nonlinear restraints. It also applies the relationship to derive optimal impact pulses that minimize occupant response for linear and nonlinear restraints. The relationship offers a new viewpoint to impact pulse optimization and simplifies the process mathematically. In addition, the effects of different vehicle impact pulses on the occupant responses with nonlinear restraints are studied. Finally, concepts of equivalent pulses and equal intensity pulses are presented for nonlinear restraints.

A modeling methodology is being developed to aid in routing and predicting movement of brake hoses with the objective of having an adequate representation in a Computer Aided Design (CAD) system for virtual prototyping. Once mount points and orientations have been specified,material properties and length determine the path of the hose. Data, collected on a straight and deflected hose at several points along the length of the hose, were compared to an ADAMS simulation. Problems that were encountered in metrology and data transfer are discussed along with their potential impact on the modeling accuracy.

The need for low pass filters stems from a need to eliminate high frequency noise from raw data (the output of the data acquisition system). As an example, consider the frame of a vehicle used in a crash test. The frame will exhibit high frequency vibrations, which do not affect the vehicles movement in space. The use of filters has since been expanded to include such things as the calculation of potential injury. Phaseless filters are now required for all FMVSS-208 injury calculations (see references). A single filter formula can not allow all test facilities to comply with the J211 CFC corridors. Even the SAE J211 recommended Butterworth filter may not comply with the J211 requirements. A new, universal, filtering system is required to harmonize the data processing at all testing facilities. The use of Fourier series for filtering provides a very powerful, yet overlooked, solution to today's filtering problems.

Traditional methods used to produce a die set (from developing initial machining cutter paths through finalized die tryout to produce a part that meets design intent) begin with draw simulation and development. It is here, traditionally, that scientific evaluation of actual metal stretch and theoretical ideals end. In past programs, a designed part would be simulated for stretch and a development model created to include various die compensations (i.e. springback, overcrown, etc.) based on past experience for area and amount. At this point, the die is cut and undergoes a metamorphosis through die tryout to finally produce a quality part. This is currently an open loop system. This paper will focus on the differences in the predicted way the die should look and the actual outcome (after part buyoff).

Airbag-related out-of-position (OOP) injuries in automotive crash accident have drawn great attention by public in recent years. In the interim-final rule of Federal Motor Vehicle Safety Standards that NHTSA issued in May 2000, OOP static test becomes a mandatory requirement of new regulation and will be phased in starting from year 2003. Due to the complexities and constraints of vehicle design, such as extreme vehicle styling and packaging as well as multiple safety requirements, it is a great challenge for both restraint safety suppliers and automobile manufacturers work together to come up with proper designs to meet requirements of new regulation and provide additional protection for both in-position and OOP occupants at various vehicle crash scenarios. In this paper, the technique of developing advanced restraint system and mitigating the OOP injuries is described.

Single-plane balancing is a very well-understood process, whereby an imbalance vector is determined and then opposed by a similar vector of equal magnitude but 180° out of phase. This is used in many situations to improve machine performance, vibration, noise etc. However, there is inherent in this process a sensitivity to errors of measurement and correction, since a large imbalance vector and the equally large correction vector must be of exactly equal magnitude and exactly 180° apart for perfect balance. This paper examines the effect of errors in measurement of the initial imbalance and correction of it on the residual balance of automotive drivelines. In particular, it examines the effects of the errors present in a system whereby a system balance correction is made, on a driveline assembly, at discrete points around a given plane (at bolt locations). Errors occur in measurement of vibration, in calculating correction masses and in applying those correction masses.

This paper describes additional and more recent results from the DaimlerChrysler study of HANS that includes a sensitivity analysis of HANS performance to variations in crash dummy neck length and other impact test conditions. The objective of the tests was to determine the robustness of the HANS concept in a variety of conditions that might occur in actual use. The results show that the variations in test parameters do effect injury measures from the crash dummy, but HANS provides substantial reductions in injury potential in all cases compared to not using HANS. Also, no injuries were indicated with HANS.

A comparative investigation of airbag and HANS driver safety systems was carried out (HANS, is a Registered Trademark in the U.S.A.). With both systems, head and neck loads were reduced from potentially fatal values to values well below the injury threshold. Both systems performed similarly in reducing the potential for driver injury. For this reason and given the high costs of development and testing, there is no justification for further development of airbags for racing.

A comparison of the Q3 and Hybrid III 3-year-old crash test dummies is presented in this paper. The performance of the dummies were compared in sixty biofidelity tests, seventy-seven static out-of-position airbag tests and sixty- three calibration tests. Various time histories and other data pertaining to accelerations, deflections, forces and moments are compared. In addition, the ease of positioning, handling, and the durability of the dummies in various out- of-position test configurations was assessed. Both the Q3 and Hybrid III 3-year-old dummies were calibrated to their respective specifications. The Hybrid III 3-year-old met its calibration requirements, while the Q3 did not always meet its own calibration requirements. The calibration specifications of the Q3 dummy need to be re-examined and possibly refined. The biofidelity of the Q3 and Hybrid III 3-year-old dummies were evaluated in both frontal and lateral test modes.