Vibration Analysis of Eight-wheel Lunar Rover with the Torsion-bar and Rocker Structure

Vibration analysis is an important route for improving the driving smoothness and stability of lunar rover. The structure characteristic of the eight-wheel lunar rover with tension-bar and rocker structure is that the ground flatness inputs of each two wheels hinged by the same rocker are intercoupling. The ground flatness excitation is equivalently transformed, which is the main excitation source, then the equivalent ground flatness function is obtained and, the vibration model and differential equation of the vibration system of the 7 DOF lunar rover are established. The differential equation of the vibration system is solved by Gaussian elimination and Runge-Kutta numerical method after Fourier transformation. The amplitude-frequency characteristic curve of the bodywork center of mass, the amplitude-frequency characteristic curve of vibration acceleration, and the relation curve between damps and the root mean square of the suspension flexibility were got by programming by means of Matlab. The driving smoothness and stability of the lunar rover is analyzed. The factors in the driving smoothness and stability are pointed out. And the variation range of damps for improving the driving smoothness and stability is presented.