Axiomatic Design of the Motor Driven Tilt/Telescopic Steering System for Safety and Vibration

Abstract

The design process of the motor-driven tilt/telescopic steering column is established by an axiomatic design approach in conceptual design. Since independent design parameters are defined for improving the performance of the steering system, each detailed design can be carried out independently. In detailed design, occupant safety in a crash environment and vibration reduction are considered. The occupant analysis code SAFE (Safety Analysis For occupant crash Environment) is utilized to simulate the body block test. Segments, contact ellipsoids and spring-damper elements are used to model the steering column in SAFE. The model is verified by the result of the body block test. After the model is validated, the energy absorbing components are designed using an orthogonal array. Occupant analyses are performed for the cases of the orthogonal array. Final design is determined for minimum occupant injury. For vibration analysis, a finite element model of the steering column is defined for the modal analysis. The model is validated by vibration experiments. Size and shape variables are selected for the optimization process. Optimization is conducted to minimize the weight subjected to various constraints.