SDRE Control of Flexible Beam Manipulator

This paper deals with dynamic modeling and tip position control of flexible beam manipulator with flexible joint while suppressing the link vibrations. The nonlinear dynamic model of the flexible beam manipulators has been derived using the idea of Lagrangian mechanics and assumed modes method (AMM). A complete model has derived with damping and friction effects in addition to rotor inertia and joint flexure while considering payload at its end point. Then, control strategy based on the nonlinear State Dependent Riccati Equation (SDRE) has been designed for precise position tracking and vibration suppression. The nonlinear SDRE control law is derived as minimizing a quadratic cost function that penalizes the states and the control input torques. The effectiveness and feasibility of the proposed control algorithm are verified by numerical simulation. The performance of the proposed controller has been presented in time domain by comparing with conventional LQR controller.