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In the 1999 Supplemental Notice for Proposed Rulemaking (SNPRM) for Advanced Airbags, the National Highway Traffic Safety Administration (NHTSA) sought comments on the maximum speed at which the high-speed, unbelted occupant test suite will be conducted, i.e., 48 kph vs. 40 kph. To help address this question, an analysis of constraints was performed via extensive mathematical modeling of a theoretical restraint system. First, math models (correlated with several existing physical tests) were used to predict the occupant responses associated with 336 different theoretical dual-stage driver airbag designs subjected to six specific Regulated and non-Regulated tests.

A method is described for predicting the reliability and useful life of an automotive powertrain system using a warranty database or from warranty records. The database requires failure corrections for misdiagnosis from duplicate data, trouble-not-identified records and multiple failure modes. Compensations not included in the database for high-mileage drop-out and warranty repairs less than the deductible amount, are also necessary. As an example, the cumulative hazard function of the Bathtub Hazard Rate distribution is fitted to the converted removal data of a typical automotive powertrain, to determine the product life characteristics. An algorithm written in Basic language is used to obtain the analytical results.

This paper outlines the key elements in a laboratory reliability verification test program for an automotive sub-system. Many of these elements are described in some detail through the various stages of development from prototype concept to production. By means of an actual case study, verification testing of the 1970 Ford Anti-Theft Steering Column, steps required to design tests which yield meaningful information and the rationale used to analyze the results are presented. The steering column on a late model automobile is a complex system which combines several functions and features; steering, shifting, warning devices (turn signal and emergency flashers), ignition switch, anti-theft devices plus several safety features. The effectiveness of the overall verification program is evaluated through the presentation of actual field-feedback results.