Position Control of Flexible Robot Arms Using Mechanical Waves

Abstract

A novel position control strategy for flexible robot arms based on wave propagation and absorption techniques is presented. The arm is modeled by a lumped-parameter mass-spring system with an actuator at one end and a load mass at the other. The actuator is required to position the remote load and, simultaneously, to provide active vibration damping. It does so by propagating mechanical waves through the system and absorbing reflected waves. Only the first two masses and springs need to be characterized and observed to determine the required actuator movement. The control algorithm is robust and compares very favorably with the time-optimal performance of bang-bang control. It is also inherently adaptive.