Output Feedback Stabilization of Flexible Joint Single Link Robotic Manipulator Using Extended Order High-Gain Observer

In this paper, a robust output feedback control (OFC) is designed for the flexible joint single link robotic manipulator. The control design is based on the feedback linearization control technique which is opted owing to its simplicity. The state estimation is carried out using a high-gain observer (HGO). Due to its vulnerability to parametric variations and external disturbances, an extended order high-gain observer (EOHGO) is then designed to eliminate the aforementioned drawbacks. The proposed controller and observers are validated using MATLAB simulations. The results illustrate that the EOHGO shows robustness against parameter variations and external disturbances which makes it appropriate for practical implementation to a flexible joint n-link manipulator.