Closed-Loop Input Shaping with Quantitative Feedback Controller Applied to Slewed Two-Staged Pendulum



In this paper, 2 practical techniques for control of dynamic systems are integrated. An input shaper is placed outside of a closed-loop system to reduce vibrations induced by the reference input. A quantitative feedback controller handles the vibrations induced by disturbances and noise while ensuring good tracking and stability. They are practical because designing an input shaper only requires knowledge of natural frequencies and damping ratios of the system whereas a quantitative feedback controller lets the designer quantitatively evaluate tradeoffs among tracking, disturbances and noise rejections, and stability among others. Various frequency-domain specifications are combined for the controller to meet requirements for all plants in an uncertain plant set. The proposed control system is applied to a 2-staged pendulum to suppress residual vibration from point-to-point movement.


Closed loop, input shaping, quantitative feedback, vibration reduction, two-staged pendulum

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Last updated: 13 February 2019