Tracking Control of a Miniature Flexible Arm Using Piezoelectric Bimorph Cells

A theoretical and experimental study is presented for the end- point control of a slender flexible arm driven by piezoelectric bimorph cells. A discrete-time formulation is presented for the arm-cell system and applied to the problem of moving the arm so that the tip closely tracks the fluctuation of target. The tip displacement (versus time) is compared with the target fluctuation, and the tip position error is used, together with other estimated system states, as the basis for applying control voltage to the cells. Both simulation and experimental results show that the PID control using the piezoelectric cells as the actuators is sufficient to make the arm tip follow the fluctuation of target precisely.