Adaptive control of a single-link flexible manipulator in the presence of joint friction and load changes

A method for controlling single-link, lightweight, flexible manipulators is proposed. The objective of this method is to control the tip position of the flexible manipulator in the presence of joint friction and changes in the payload. Both linear and nonlinear friction are overcome using a very robust control scheme that is based on two nested feedback loops: an inner loop to control the position of the motor and an outer loop to control the tip position. Changes in the load are compensated by decoupling the dynamics of the system and then applying a very simple adaptive control for the tip position. This results in a quite simple control law that requires minimal computing effort and thus can be used for real-time control of flexible arms