Abstract: In order to solve the contradiction between the lighter weighting,modal characteristics and pedestrian crash safety of the electric car hood,the structure optimization design of electric car hood was carried out by the HyperWorks software.Firstly,the pedestrian head collision simulation was carried out,and calculated the HIC value of head injuries.Secondly,the multi-objective topology optimization design for the electric car inner hood was conducted with compromise programming method.Then,the collision simulation and structural strength were validated by test for the improved model.Finally,the multi-objective size optimization design for the electric car hood was conducted by the adaptive response surface method.The optimization results show that the mass of the electric car hood after optimization is reduced by 8.8 %,the low order natural frequency values are greater than the resonance frequency,and the HIC value of electric car hood is 858.6.The results are satisfied with the standard of the Chinese pedestrian safety protection regulations.

Key words: electric car hood, HyperWorks software, compromise programming method, multi-objective topology optimization, adaptive response surface method