Robust Feed-Forward Schemes for Anti-sway Control of Rotary Crane

This paper presents investigations into the development of robust feedforward control schemes for anti-swaying control of a rotary crane system. A nonlinear rotary crane system is considered and the dynamic model of the system is derived using the Euler-Lagrange formulation. An unshaped square-pulse torque input is used to determine the characteristic parameters of the system for design and evaluation of the feedforward control techniques. Feedforward control schemes based on input shaping and filtering techniques are to be examined. Simulation results of the response of the rotary crane system to the shaped inputs are presented in time and frequency domains. Performances of the control schemes are examined in terms of sway angle reduction and time response specifications. Moreover, the robustness of the feedforward control schemes is discussed. Finally, a comparative assessment of the proposed control techniques is presented and discussed.