Input Shaping is a widely used method of suppressing residual vibrations in point-to-point motion of flexible bodies. It is easy to implement and gives good results if the dynamics of the system are known accurately. However, it is not very robust to system parameter variations. Early methods of increasing the robustness incurred a large time penalty. Hence attempts were made to apply adaptive control to increase the robustness of the shaper. These methods met with varying degrees of success. In this paper, we propose a new adaptive control scheme which is effective in increasing the robustness of the shaper, even in the presence of additive noise in the system output. It is also able to handle sudden changes in the plant parameters. The performance of the system in the presence of high-order unmodelled dynamics is also studied and found to be satisfactory.
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