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By-wire systems have the potential of augmenting the normal capabilities of human drivers as well as serving as enablers for emerging safety technologies. To achieve these features, these systems must be carefully designed, analyzed, and verified for safety because they are new, complex, and potentially exhibit new and different failure modes and effects. Duplication may be required to ensure that safety margins are met in the presence of faults. Full duplication of every system may not lead to a cost effective implementation, especially if multiple independent by-wire systems are placed on a single vehicle. Other architectural approaches for the integration of by-wire systems need to be considered and analyzed. These architectures should meet if not exceed the safety requirements while providing a more cost effective implementation than a fully duplicated architecture.

This report presents the test methods and results of a study involving lap/shoulder belted dummies in dynamic dolly rollover tests and inverted vehicle drop tests. Data are presented showing dummy neck loadings resulting from head impacts to the vehicle interior as the vehicle contacts the ground. Comparison of the number and magnitude of axial neckloads are presented for rollcaged and production vehicles, as well as an analysis of the factors which influence neckloads under these conditions.

This paper presents results of a three-phase research project aimed at understanding how future automotive interior materials should be selected or designed to satisfy the needs of the customers. The first project phase involved development of 22 five-point semantic differential scales to measure visual, visual-tactile, and evaluative characteristics of the materials. Some examples of the adjective pairs used to create the semantic differential scales to measure the perceptual characteristics of the material are: a) Visual: Light vs. Dark, Flat vs. Shiny, etc., b) Visual-Tactile: Smooth vs. Rough, Slippery vs. Sticky, Compressive vs. Non-Compressive, Textured vs. Non-Textured, etc., c) Evaluative (overall perception): Dislike vs. Like, Fake vs. Genuine, Cheap vs. Expensive, etc. In the second phase, 12 younger and 12 older drivers were asked to evaluate a number of different automotive interior materials by using the 22 semantic differential scales.

Contamination protection of brake rotors has been a challenge for the auto industry for a long time. As contamination of a rotor causes corrosion, and that in turn causes many issues like pulsation and excessive wear of rotors and linings, a rotor splash protection shield became a common part for most vehicles. While the rotor splash shield provides contamination protection for the brake rotor, it makes brake cooling performance worse because it blocks air reaching the brake rotor. Therefore, balancing between contamination protection and enabling brake cooling has become a key critical factor when the splash shield is designed. Although the analysis capability of brake cooling performance has become quite reliable, due to lack of technology to predict contamination patterns, the design of the splash protection shield has relied on engineering judgment and/or vehicle tests. Optimization opportunities were restricted by cost and time associated with vehicle tests.

An analysis is presented that was used to interpret the significance of response measurements made with a specially instrumented, 3-year-old child dummy that was used to evaluate child injury potential of the second-generation, passenger inflatable restraint system that was being developed by General Motors Corporation. Anesthetized animals and a specially instrumented child dummy, both 3-year-old child surrogates, were exposed to similar inflating-cushion, simulated collision environments. The exposure environments were chosen to produce a wide spectrum of animal injury types and severities, and a corresponding broad range of child dummy responses. For a given exposure environment, the animal injury severity ratings for the head, neck, thorax and abdomen are paired with dummy response values corresponding to these body regions.

A family of adult and child size dummies was developed under the direction of two task groups of the SAE Mechanical Human Simulation Subcommittee of the Human Biomechanics and Simulation Standards Committee. These new child size dummies represent fiftieth percentile children who are 6 months, 12 months, 18 months, 3 years, and 6 years old. The sizes and total body weights of the dummies were based on detailed anthropometry studies of children of these ages. The techniques used to establish the segment masses and the resulting design goals are detailed. Appropriate impact response requirements were scaled from the biofidelity response requirements of the Hybrid III, taking into account the differences in size, mass and elastic modulus of bone between adults and children. The techniques used to establish the biomechanical impact response requirements for the child dummies are discussed and the resulting biomechanical impact response requirements are given.

Even with the rapidly evolving computational tools available today, suspension design remains very much a black art. This is especially true with respect to road cars because there are so many competing design objectives. In a racecar some of these objectives may be neglected. Even still, just concentrating on maximizing road-holding capability remains a formidable task. This paper outlines a procedure for establishing suspension parameters, and includes a computational example that entails spring, damper, and anti-roll bar specification. The procedure is unique in that it not only covers the prerequisite vehicle dynamic equations, but also outlines the process that sequences the design evolution. The racecar design covered in the example is typical of a growing number of small open wheel formula racecars, built specifically for American autocrossing and British hillclimbs.

By using descriptive charts and graphs, this report provides an analysis of the IDB-C network at the Subsystem level and at the vehicle level, using data comparison between modeling and simulation of the network and measurement and analysis on physical systems.

The paper solves the problem of increasing the accuracy of measuring torque and use of an electronic torque meter as a feedback sensor of synchronous and induction machines of an electric traction drive. Relevance of the problem and methods for its solving by indirect means using simulation models of electric machines are considered. The theoretical development of the meter is based on the energy model of electric machines in the form of differential equations for active and reactive power balance. This eliminates the direct influence of instability and nonlinearity of inductive elements and takes into account electrical, magnetic, mechanical, and harmonic losses using the simplest algorithms. Key variables of the model in the form of total active power and angular velocity are measured directly, and the high nominal efficiency of traction machines (95%) provides a wide tolerance range for calculating total losses.

This pager documents a one shift (10 hour) wind tunnel test program conducted on a Corvette C5 prepared for Sports Car Club of America (S.C.C.A.) World Challenge racing. The testing was conducted at the Canadian National Research Center in Ottawa, Canada. Specific areas of test included front fascia and under tray, rear air discharge, rear wing configuration and angle, B-pillar configuration, and ride height. Standard wind tunnel test procedures were followed. In total twenty-six separate configurations were evaluated. Data for front and rear lift, total drag, and lift/drag (L/D) ratio are provided for each test configuration. The cumulative effects of the aerodynamic changes evaluated in this program, calculated at 192 KPH (120 MPH), increased front down force by 318 N (72 Lb.), and rear down force by 770 N (173 Lb.). Lift/drag ratio was improved from -0.597 to -1.016. These changes increased total drag by 381 N (86 Lb.).