Unlike traditional fixed-base manipulators, manipulators used in space are mounted to a spacecraft whichmay move freely in response to any forces or torques. This results in a highly coupled dynamical system.In the past, robotic arms have often been slow and lightweight in comparison to their host spacecraft;but as economic incentives drive the development of smaller, faster, lighter vehicles, this coupling willpresent an increasing challenge in the development of suitable control systems. To improve understandingof the dynamics of this coupled system and to demonstrate and validate proposed controllers in the spaceenvironment, the University of Maryland Space Systems Lab is constructing the Dynamic ManipulationFlight Experiment (DYMAFLEX) microsatellite, the development of which is partially funded by theUnited States Air Force University Nanosat Program. Equipped with a high-performance manipulatorrepresenting approximately 14% of the mass of the combined system and having greater rotational inertiaat full extension than the spacecraft itself, the DYMAFLEX vehicle represents the ideal test bed for spacemanipulator dynamics and control. This paper presents an overview of space manipulator control as it relatesto the DYMAFLEX science mission, with simulation results exploring an intended maneuver in Cartesianspace. The mission is designed to provide empirical validation of existing models for the behavior of aspace manipulator as well as to provide a basis for comparison between proposed control strategies to assesstheir strengths and weaknesses in the actual application environment. In this paper, a simple TransposeJacobian controller is compared to more sophisticated approaches, including the Modified Transpose Jacobiancontroller of Papadopoulos and Moosavian. A technique is proposed for mitigating the chattering problemassociated with the MTJ strategy. The effect of measurement noise is explored. An adaptive controller isconsidered as a further means of improving performance. Preliminary conclusions are drawn, to be verifiedon the DYMAFLEX platform.
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