On-orbit assembly technology is a key for future large-scale structure construction. For several decades, many concepts of space structures have been proposed and some of them have the idea of robotic construction systems. Authors have developed a concept of a truss joint system for largescale orbital structures and worked for space robotics research. Participating aJapanese space robotics experiment project on Engineering Test Satellite No. 7 scheduled to be launched by NASDA in 1997, the authors will conduct spare truss construction experiments. The experiments have objectives to establish basic technologies of on-orbit assembly work and robotic construction by using NA SDA's manipulator on the satellite. Our experiment system consists of the experiment unit including a truss joint anda deployable truss on the satellite, and our teleoperation facility on the ground The on-board truss unit has been tested in both vibration and thermal vacuum conahtions simulating orbit environment, and the ground teleoperation facility has been developed The actual experiments will start in late 1997.