Axiomatic design of the motor-driven tilt/telescopic steering system for safety and vibration

The design process of the motor-driven tilt/telescopic steering column is e stablished by an axiomatic design approach in conceptual design. Since inde pendent 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 reduc tion are considered. The occupant analysis code SAFE (Safety Analysis For o ccupant crash Environment) is utilized to simulate the body block test. Seg ments, 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 bl ock test. After the model is validated, the energy absorbing components are designed using an orthogonal array. Occupant analyses are performed for th e cases of the orthogonal array. Final design is determined for minimum occ upant injury. For vibration analysis, a finite element model of the steerin g column is defined for the modal analysis. The model is validated by vibra tion experiments. Size and shape variables are selected for the optimizatio n process. Optimization is conducted to minimize the weight subjected to va rious constraints.