Considering gravity change from ground alignment under the gravity environment to space applications under the micro-gravity environment, a sliding mode controller(SMC) is proposed to control the space manipulator. An SMC based on the reaching-law is proposed by introducing a nonlinear structure of special configuration fal function. The asymptotic stability of system is guaranteed based on the Lyapunov theory. Simulation results show that by using this strategy, the
system can complete the trajectory tracking task under the different gravity environment and has strong robustness.