The application of an input precompensation scheme for vibration suppression in slewing flexible structures, with particular application to flexible-link robotic manipulator systems, is considered. The control from such input shaping schemes corresponds to a feedforward term that convolves in real time the desired reference input with a sequence of impulses and produces a vibration-free output. The robustness of such an algorithm with respect to modal frequency variations is not satisfactory but can be improved by convolving the input with a longer sequence of impulses, the tradeoff being a decrease in the transient response speed. An adaptive precompensation scheme is suggested in this work which can be implemented by combining a frequency domain identification scheme, used to estimate the modal frequencies on-line, with a subsequent scheme for adjusting the spacing between the impulses. The combined adaptive input shaping scheme provides the most rapid slew that results in a vibration-free output; experimental results for a single flexible link are presented to verify the technique.
ASJC Scopus subject areas
- Control and Systems Engineering
- Electrical and Electronic Engineering