Robust Topology Optimization Design Of The Guiding Arm Bracket For Vehicle Suspension

As a functional component that connects axle and frame,the guiding arm brackets of trucks have a significant iMPact on the suspension system features.In order to solve the fatigue fracture problem caused by stress concentration,improve the overall performance,a robust optimization design of the guiding arm bracket based on the finite element theory and the topology optimization method was carried out.The robust optimization design of the guiding arm bracket enhanced the structural lightweight and robustness level,while improving the static and model performance of the structure.Firstly,the existing topology and robust optimization design theory was concluded and summarized,in order to find out the development direction and the deficiency of the current structural design method,followed by the introduction of the material difference model and optimization method used in this paper.Next,a finite element analysis model of the guiding arm bracket based on the finite element theory was built to analyze the static and modal characters of the finite element model under four typical operating conditions.The results showed that the local stress of the original structure under the enhanced torsional condition exceeded the allowable stress,which was consistented with the experimental results.The allowance of stress value of the main body was low,so there existed the potential for further optimization.The main vibration direction of the structure was different from the direction of loads,providing the structure with good modal performance,which underlies the design of topology optimization and robustness hereinafter.Thirdly,the finite element topology model was established under the consideration of the working space and engineering constraints.A single objective topology optimization method was presented aiming at improving the static or the modal performance of the structure.According to the above optimization results,a multi-objective function was built based on the compromise programming approach and the average eigenvalue method.Then a multi-optimization process was conducted to polish up the overall performance,and to filter the multi-objective Pareto solutions by using discriminant function.Then,this paper analyzed the uncertainties of the guiding arm bracket,and studied the robust optimization method based on the uncertainties of amplitude and phase.It summarized the uncertain simulation methods used in the design process,and co MPared the i MPact of uncertain distribution,accuracy and dimensions of the uncertainties on the optimization Results.The results showed that the non-uniform sparse grid collocation method had good efficiency and accuracy in solving structural optimization problems.Finally,according to the robust optimization results,a new structure was put forward on account of the parametric modeling method.CoMParing with the original structure,the mass of the new structure was reduced by 5-7%;at the same time,the stress levels of the structure in various operating conditions reduced,and the weighted stiffness increased by 20%,verifying that the new structure had better overall performance.The robustness topology optimization design method used in this paper could provide a reference for the robustness design of the continuum structure.