Lightweight Design Of A Commercial Vehicle Cab Based On Topology Optimization

The cab of commercial vehicle is the part with the highest structural performance requirements for the entire commercial vehicle.Its structural performance and reliability directly affect the vehicle life cycle and vehicle market competitiveness.Based on the structural optimization method of multi-objective topology optimization,this paper optimizes the structure of the commercial vehicle cab body-in-white,proposes a lightweight plan,analyzes the lightweight plan,and finally conducts a fatigue life analysis to determine the rationality of the plan Evaluation.First of all,this article discusses the research status and development trend of structural optimization and fatigue analysis at home and abroad,and introduces the main methods of structural optimization and fatigue analysis.Then,the basic theory of structural optimization is introduced,and the multiobjective topology optimization method and theory used in this paper are introduced,and the mathematical model of multi-objective topology optimization of commercial vehicle cab body in white is initially established.What's more,the finite element model of the commercial vehicle cab body-inwhite is established,and the bending stiffness,torsional stiffness and modal characteristics of the commercial vehicle cab body-in-white are analyzed and calculated.The main structural performance of the cab body-in-white studied in this paper is obtained.Then,based on the mathematical model of multi-objective topology optimization and the performance of BIW structure,the optimization space,constraints and objective function of the topology optimization are determined.According to the results of topology optimization,a lightweight scheme is proposed to adjust the size of rear panel window and reduce the thickness of upper and front roof by 0.1mm,which reduces the weight by 2.5kg.The optimized vehicle BIW can meet the structure requirements.Finally,the fatigue life analysis of the new car body in white is carried out,and the finite element model of the cab,the fatigue characteristic curve of the material and the load spectrum are used as input to obtain the parts with weaker fatigue life value,the result shows the reliability of the lightweight solution is high.