ANALYTIC METHODS FOR SLEWING UNDAMPED FLEXIBLE STRUCTURES WITH ON-OFF ACTUATORS

Methods are presented that generate command profiles for undamped flexible systems equipped with on-off actuators. The shape of the command profiles are described by analytic functions of the system's frequency, actuator force-to-mass ratio, and the desired move distance. The commands are obtained by first canceling the flexible-body response and then accounting for rigid-body requirements. Performance measures such as, move duration, fuel usage, peak transient deflection, and robustness to modeling errors indicate that the analytic commands are attractive alternatives to time-optimal commands.

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