Position control of single link flexible manipulator: a functional observer-based output feedback sliding mode approach

Single link flexible manipulators have the advantage of a higher degree of manipulability as compared to rigid manipulators. However, their inherent structural flexibility causes the deformation of the manipulator link during task. The dynamic model of a flexible manipulator, which is ideally represented by a partial differential equation (PDE), is not be always conducive to the design of a comprehensive controller. To address this issue, this work proposes a controller design based on a balanced truncated model that effectively contains the dominant dynamics of the single link flexible manipulator system, which substantially reduces the computational cost of controller implementation while also simplifying the design process. Further, the work also proposes a strategy to design a robust functional observer-based output feedback sliding mode controller for position control of the single link flexible manipulator. The numerical simulation results demonstrate the efficacy of the proposed control algorithm compared to the state-of-the-art controllers used for comparison.