Adaptive fault-tolerant visual control of uncalibrated eye-to-hand manipulator based on proportional-actuation strategy

In this paper, an adaptive actuator failure compensation control scheme is proposed for visual servoing of an eye-to-hand robotic manipulator with redundant actuators at joints, for which a precise calibration of camera is not required. And the stuck-type as well as time-varying actuator failures are considered in control design. Furthermore, a proportional-actuation strategy to accommodate different output capacities of the redundant actuators is newly developed. And a decoupling method is proposed, based on which the unknown actuator failure parameters and camera parameters can be estimated independently. Moreover, a novel framework for stability analysis is given, which enables us to prove the convergence of image errors and the boundedness of all closed-loop signals. Finally, the effectiveness of our scheme is validated by simulation results.