Dynamic analysis of flexible space manipulators with harmonic reducer

Space manipulator is an important tool for spacecraft to complete a variety of tasks in space. The trajectory precision of the manipulator determines whether the mechanism performs normally. Nowadays the harmonic drive is widely used as the reducer in the space manipulator, which may influence the dynamical properties of the flexible space manipulator. This paper establishes the dynamical models of space manipulator considering the harmonic hysteresis phenomenon derived from the harmonic reducer. A numerical simulation is proposed to analyze the nonlinear dynamic characteristics of flexible space manipulator with harmonic drive. The results of angular velocities reveal that non-linear and high-frequency disturbance detected in the output dynamical property is caused by flexibility of the space manipulator. Moreover, the observed hysteresis phenomenon in the dynamic behavior is not only determined by the flexibility of manipulator but the transmission feature embedded the harmonic drive.