A novel tool exchange device for space robots

Since space tasks turn more complicated, tool exchange on orbit is playing a key role. This paper develops a novel tool exchange device(TED) and its fixture. It can not only realize the electrical interface connection with the end tool, but can output torque to it directly. Moreover, when the TED docks with the fixture, using intermittent motion characteristic of maltese mechanism, such operations as latching, shaft connection and electrical connection are carried out only by a motor, which reduces complexity of the system and improves the reliability. At last, with a 4 degree-of-freedom (DOF) space robot platform, the experiment of tool exchange is completed successfully based on the position impedance control method. Experimental results show the TED's pose (position and orientation) tolerance is up to 10mm and 3°.