Manipulation of flexible structural modules by space robots during LSS construction

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2005.Includes bibliographical references (leaves 86-90).Future space structures are expected to have very large size. Such Large Space Structures (LSS) will be constructed in-orbit, probably by assembling large structural modules. This is a dangerous and difficult task for humans. On the other hand, this is a challenging and promising application for space robotics. This work provides a planning and control architecture for the manipulation of a large flexible structural module in the proximity of the LSS, by a team of space manipulators that are mounted on the LSS. In this task, the payload (module) and the base structure (LSS) of the robots are assumed to be very compliant. Interface forces between robots and flexible structures induce undesirable vibration. The approach developed here is to plan and control the forces that robots apply to the flexible structures so that they maneuver the module precisely while exciting low levels of residual vibration in the module and the LSS. Robot use different control implementations to control the forces they apply to different kinds of flexible structures. Robots plan and control cooperatively the forces they apply to the module.(cont.) Each robot exploits its redundancy to minimize the base reaction forces it applies to the LSS and to avoid undesirable configurations. Simulation results demonstrate the effectiveness of the developed architecture in positioning the module precisely and exciting low levels of residual vibration in the module and the LSS.by Dimitrios Spyridon Tzeranis.S.M