Study On The Weight Reduction Of The Upper Arm Of An Electric Vehicle Suspension

With the increasingly serious environmental problems,for the automotive industry,automobile lightweight is an important way to solve environmental problems.Suspension is an important part of the car chassis,and the swing arm is an important force transmission component of the suspension.At present,the lightweight of automobile chassis parts is an important research direction in the automotive field.The lightweight of the suspension system is particularly important,and the swing arm is lightweight can reduce environmental pollution,save energy and protect the environment.The research object of the subject is the swing arm on the suspension of an electric van transport vehicle,to study the weight reduction of the swing arm of a vehicle.Under the conditions of pit crossing,turning and braking,the force analysis of the vehicle,the force situation of the vehicle ground point,and the suspension kinematics analysis and related parameters are used to extract the load of the hinge point of the upper swing arm.Use Hyper Works software to analyze the strength,stiffness and natural frequency of the original steel swing arm to determine the original steel swing arm under pit crossing,turning,braking,X stiffness,Y stiffness,and free mode conditions Performance.Under the condition that the original swing arm structure is unchanged,the aluminum material is used instead of the steel material.The finite element analysis of the swing arm is performed under the same working conditions.The optimization results are compared with the performance of the original steel swing arm.The maximum stress under braking conditions is 219 MPa,Exceeding the yield strength of aluminum alloy by 205 MPa,indicating that this optimization scheme is not feasible.According to the finite element analysis results of the original steel upper swing arm,the stress,stiffness and natural frequency are used as the structural performance indicators.In the pit crossing,turning,braking,X-direction stiffness,Y-direction stiffness,free-mode working conditions,etc.Under the conditionof topology optimization,constrained by the volume fraction,the topology optimization of the aluminum alloy upper swing arm and the verification of the topology optimization scheme are feasible.The maximum strength of the topological structure is about half of the yield strength of the aluminum material,and all properties meet the requirements.In order to achieve the best structural optimization of the upper swing arm,the shape of the upper swing arm of the topological structure needs to be optimized again.Under multiple operating conditions such as braking,X-direction stiffness,Y-direction stiffness,and free-mode conditions,10 design variables are taken to optimize the shape of the upper swing arm,and finally the shape optimization structure is verified.In the subject,the top swing arm is optimized by topological optimization method,and then the shape optimization method is used to optimize the top swing result.The finite element analysis result of the upper swing arm is co MPared with the original cast steel analysis result.The quality of the original steel upper swing arm is 15.08 kg,the weight of the upper swing arm optimized for topology and shape structure is 5.63 kg,the weight reduction effect of the upper swing arm is 62.6%,the first-order and second-order natural frequencies are increased by 67.7%,60.6%,and the X direction is decreased by 8.8%,The Y-direction stiffness has been increased by 6.8%.The new aluminum alloy swing arm stiffness,strength,and modal meet the structural performance requirements,indicating that the weight reduction can be achieved under the premise of ensuring the performance structure.