LPV fault estimation and FTC of a two-link manipulator

This work is motivated by the challenge to develop an adaptive strategy for systems that are complex, have actuator faults and are difficult to control using linear methods. The novelty lies in combined use of LPV fault estimation and LPV fault compensation to meet active FTC performance requirements. The paper proposes a new design approach for systems which can be characterized via sets of LMIs and can be obtained using efficient interior-point algorithms. A polytopic LPV estimator is synthesized for generating actuator fault estimates used in an FTC scheme to schedule the nominal system state feedback gain, thereby maintaining the system performance over a wide operating range within a proposed polytopic model. The active FTC controller is a function of fault effect factors derived on-line. The effectiveness of the proposed method is demonstrated through a nonlinear two-link manipulator system with torque input faults at each joint.