Experimental Verification of Real-Time Control for Flexible Systems With On-Off Actuators

A technique for driving a flexible system with on-off actuators is presented and experimentally verified. The control system is designed to move the rigid body of a structure a desired distance without causing residual vibration in the flexible modes. The on-off control actions are described by closed-form functions of the system's natural frequency, damping ratio, actuator force-to-mass ratio, and the desired move distance. Given the closed-form equations, the control sequence can be determined in real time without the need for numerical optimization. Performance measures of the proposed controller such as speed of response, actuator effort, peak transient deflection, and robustness to modeling errors are examined. Experiments performed on a flexible satellite testbed verify the utility of the proposed method.

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