| Lightweight and miniaturization is a major trend of global automobile design.Adopting scientific and reasonable methods to design the UGV frame with light weight can not only greatly reduce the weight of vehicle,but also shorten the design cycle,save costs,improve the number of onboard equipment in the vehicle,so as to realize more intelligent functions.Therefore,it is necessary to reduce the weight of the frame on the premise of satisfying the mechanical properties of the vehicle.In this paper,the UGV frame developed by an enterprise was taken as the research object to achieve lightweight design by using multiple load cases collaborative topology optimization.According to the parameters of the original frame,the finite element model of the frame is established.The modal analysis and static analysis of the original frame under nine typical load cases were carried out.Subsequently,referring to the basic structure of the frame,three kinds of aluminum alloy specimens were constructed,and the modal and static experiments were carried out.According to the experimental conditions,the finite element model was established.The relative error between the experimental results and the calculation results is small,which verifies the accuracy of the finite element model and the analysis calculation.In addition,the static analysis results show that the strength of the original frame does not meet the design requirements and further optimization was needed.On the basis of the original frame structure and the load distribution of vehicle,this paper built the topology optimization space.The new body frame was obtained by using the method of multiple load cases collaborative topology optimization.Finally,a variety of finite element analysis was carried out for the reconstructed frame.Compared with the results of the finite element analysis before and after the optimization of the frame,it can be seen that the optimized frame not only improves the rigidity,strength and crashworthiness,but also reduces the weight by 124.5 kg,and the weight reduction ratio reaches 21.1%,achieving the goalof lightweight.The work of this paper has important guiding significance for the lightweight design of frame structure,and provides a reference for relevant enterprises and institutions. |
