Self-excited Vibration Control of the Flexible Planar Parallel 3- R RR Robot

A self-excited vibration active control approach for a 3-RRR flexible planar parallel robot is developed to improve accuracy and stability. The 3-RRR parallel flexible robot experimental setup is constructed. From the motion experiments, it is demonstrated that the residual vibration can be converted to self-excited vibration at a high-speed motion, which will affect the stability and positioning precision of the platform. To suppress the self-excited vibration owing to flexibility, friction, backlash, coupling, and other nonlinear factors, a nonlinear controller and a fuzzy control algorithm are designed to attenuate the self-excited vibration. Experiments are conducted in different positions of the 3-RRR flexible parallel robot. The experimental results demonstrate that the investigated control methods can suppress the self-excited vibration effectively.