Structural Optimization and Reliability Analysis of Automotive Composite Bumper Against Low-Velocity Longitudinal and Corner Pendulum Impacts

To improve the safety performance and maintain light weight of composite automotive bumper beams subjected to low-velocity impacts, a structural optimization and a novel reliability analysis procedure for multi-objectives are established in this paper. Both longitudinal and corner pendulum impacts are considered, and the optimized bumper beam has significant improvements. Compared with the original composite bumper beam, the section force of the crash box in the corner pendulum impact and the mass of the optimal bumper beam are decreased by 9.6% and 20.3%, respectively. The novel reliability analysis results show that the knee point may be less reliable whereas the design with inferior knee point is of higher reliability. Therefore, a design on an inferior knee point may be more attractive in engineering design practices. Our numerical results have demonstrated that the optimization procedure established in this paper to improve the performance of composite bumper beams and our proposed reliability analysis method considering multi-objectives are effective and useful in the engineering design of bumper beams. These techniques are also useful for the design of other types of structural components where weight and safety are of importance.