Moving Force of Rear Axle Under Rough Road

With considering elastic and damping modulus of suspendens and wheels, a vehicular model of system′s vibration and a differential equation group of vibration with influence of rough road were built. This differential equation group is a ordinary differential equations and initial conditions can be found or assume. With Laplace change and theory of lineal system, a method of calculable systematical selffrequencies was given, and the analytic result of differential equation was obtained. With the relation between the special solution and common solution of a differential equation,a number result was got. The analytic result lays stress on controlling study and number result lays stress on calculation result. The number result can be used in program and simulink, especially NewtonRaphson method was recommended. These results amend the express styles of rear axle in moving force. A preparedness for finite element in design and simulation was done.