An observer based control strategy is proposed for a flexible Cartesian (SCARA) Robot which is modeled as a flexible cantilever beam with a translational base support. A piezoelectric (PZT) patch actuator is bonded on the top surface of the flexible arm to apply a controlled moment for vibration suppression requirement. Utilizing three measurable quantities (i.e., the base displacement, arm tip deflection and the strain at the root end of the arm), a reduced-order observer is designed to estimate the velocity related variables, which are not measurable. A simple PD controller is selected for the moving base regulation control, while a Lyapunov function candidate based on a very simple energy relationship is utilized for the PZT input voltage to make the closed-loop system energy dissipative and hence stable. In this paper, the PZT input voltage control uses the velocity related signals estimated by the reduced-order observer, which makes the control structure simpler. The feasibility of the controller is validated by the numerical simulations and experimental results.
A Reduced-Order Observer Based Piezoelectric Control of Flexible Cartesian (SCARA) Robot Manipulator
Liu, Z, Jalili, N, Dadfarnia, M, & Dawson, DM. "A Reduced-Order Observer Based Piezoelectric Control of Flexible Cartesian (SCARA) Robot Manipulator." Proceedings of the ASME 2002 International Mechanical Engineering Congress and Exposition. Dynamic Systems and Control. New Orleans, Louisiana, USA. November 17–22, 2002. pp. 395-401. ASME. https://doi.org/10.1115/IMECE2002-33544
Download citation file: