Abstract
This paper presents the effectiveness of the computer based discrete time sliding mode control algorithm to compensate the attitude deviation of the main body of a free-flying space robot, which is caused by both the motion of manipulators on it, and the disturbance caused by some work such as capturing a flying target or throwing a equipment by it's arm. The controller design methodology using discrete time sliding mode control algorithm is developed. And the performance of it is compared with those of current discrete time PD control algorithm and continuous time sliding mode control algorithm by numerical simulations and a simplified model test. The discrete time sliding mode control algorithm causes no chattering that is often observed in the case of the continuous time sliding mode control algorithm. It is clarified that the discrete time sliding mode control algorithm is the highest performance and robustness among them.