Study on piezoelectric actuators in control of a single-link flexible manipulator

Describes an approach for the use of smart materials, piezoelectric materials of PVDF and PZT, for control of a single-link flexible manipulator. A combined scheme is developed, which consists of a PD feedback for rigid motion control, and a command voltage applied to the PVDF layer or segmented PZT actuator(s) those are bonded to the surface of the flexible link for vibration damping. The command voltage employs linear velocity feedback (L-type), which makes the scheme easy to implement. Global stability of the system is investigated using a Lyapunov approach. It is the first time system stability under the L-type piezoelectric actuator control, utilizing the concept of a virtual joint model, is shown. Simulation results illustrate that the PZT actuator, considering actuator placement, exhibits better performance in vibration damping over the PVDF actuator.