One-Mode Extra Insensitive Input Shapers to Reduce Residual Vibration in Flexible Arms: Experimental Verification

Input shaping is a particular feedforward-control strategy based on the convolution of an input command with a sequence of pulses, whose amplitude and application time are function of the natural frequencies of the system to be controlled. The effect consists in a significant reduction of the residual vibration, compared with the original unshaped command. This paper presents the results of the experimental tests carried out on the master robot arm of the Test-bed for Microgravity Simulation in Robotic Arm Dynamics (TeMSRAD) set up at the Department of Structural Mechanics, Università di Pavia. One-mode extra insensitive shapers were tested experimentally for different vibration limits to determine the sensitivity curve with respect to uncertainties in the system model or environmental noise typical of the operating conditions required by the International Space Station (ISS).