| Distributed drive electric,mainly characterized by electric wheel,has become the main research direction of new energy vehicles.But motor and reducer are integrated to the wheel drive system with reduction mechanism,which impacts the vehicle ride comfort because of the increasing of unsprung mass.As a result,this paper proposed an innovative design scheme and studied on the vertical vibration performance of wheel-edge driving electric vehicles.Firstly,an improvement structure scheme is proposed by analyzing the structure and shortcomings of existing wheel-edge driven system.Secondly,a 1/4 vertical vibration dynamic model was established according to the motion differential equation was derived.The simulation model was established in MATLAB/Simulink,and the simulation analysis was implemented.The contrastive study of vertical vibration characteristics was completed in the two-stage deceleration mechanism designed in this paper and the existing wheel-edge driven structure.Then,the suspension parameters were optimize by genetic algorithms,an optimized 1/4 vehicle three-DOF vertical vibration Dynamic Model was established.The contrastive study of vertical vibration characteristics was completed with the suspension parameters before and after optimization by simulation,which was carried on in MATLAB software.The simulation results show that the amplitude of the vertical vibration of the optimized suspension system is significantly reduced when the excitation frequency is about 7Hz,which can effectively improve the vehicle ride comfort.Finally,11 DOF vehicle vertical vibration Dynamics Model was established,and the simulation model was established in MATLAB/ Simulink.The vehicle dynamic performance was analyzed by simulation,and the conclusion of theoretical research was verified by testing the parameters of the experimental prototype vehicle.Research results show that the influence of the vibration on four wheels have slightly different,but which have the same trend change,which indicates vehicle vertical vibration and the roll,pitch changes consistent with actual. |
