Hybrid control schemes for input tracking and vibration suppression of a flexible manipulator

Abstract This paper presents investigations into the development of hybrid control schemes for input tracking and end-point vibration suppression of a flexible manipulator system. The dynamic model of the flexible manipulator is derived using the finite element method. Initially, a collocated proportional-derivative (PD) controller utilizing hub angle and hub velocity feedback is developed for control of rigid-body motion of the system. This is then extended to incorporate a non-collocated proportional-integral-derivative (PID) controller and a feedforward controller based on input shaping techniques for control of vibration (flexible motion) of the system. Simulation results of the response of the manipulator with the controllers are presented in time and frequency domains. The performances of the hybrid control schemes are assessed in terms of input tracking and level of vibration reduction in comparison to the PD control. The effectiveness of the control schemes in handling various payloads is also studied. Finally, a comparative assessment of the hybrid control schemes is presented.

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