Space robots work in the space instead of astronauts. They are composed of the arms (manipulators) to work and the main body of satellite. Space robots don’t have the fixed points like robots on the ground. Therefore, when the space robot moves the manipulator, the main body is also moved together, and the attitude varies. Thus space robots have a very complex dynamic property. However this complexity is characterized by the law of conservation of momentum and angular momentum known well. By considering the above, the dynamical property is found as well as the manipulator on the ground. It allows us to extend existing control rules. Furthermore, the differential equation that describes kinematics and dynamics of the system is found with considering its conservation law as the constraint condition. We show that the inertia parameters needed to control linearly appear in these equations, and develop the parameter identification method and the adaptive control method.
Space robots must accomplish various complex work under the environment not maintained unlike the robot in the factory. We have developed the element technologies of the visual information assistance and the robust control to environmental variation to obtain adaptation ability in this environment not maintained. We have also developed experimental model of space robot on the ground and have integrated it with element technologies, and have succeeded in the autonomous assembly experiment of truss structure. Moreover we study the adaptive control with neural network to make robots intelligent, the dynamical understanding of the work involving interaction with environment, the accomplishment of work based on learning, and so on.