Robust Control Method Design for Underactuated Double-Pendulum Overhead Cranes

Abstract

Overhead travelling cranes are infrastructure for building construction and their main purpose is to ensure accurate and rapid transport of goods to a given location in the shortest possible time without any residual oscillation. The overhead crane is also a typical underdrive method, which has fewer inputs than the amount being controlled. In some practical applications, uneven weight and f-loads on the hook can lead to load and hook oscillations and the bridge crane can develop the so-called double-pendulum properties. This leads to a high degree of coupling and a high degree of non-linearity between the various state variables of the crane system. The study that follows suggests a new energy-coupled control strategy for an underactuated double-pendulum overhead crane with initial control force constraints. Strong robustness and superior control performance to parameter changes and external disturbances are the proposed controller’s noticeable characteristics. To ensure the smooth start of the trolley, a robust control adds the hyperbolic tangent function to the control procedure. In addition, the stability analysis and stability verification of the control system is given by using the LaSalle’s invariance principle and Lyapunov techniques. The simulation results show that the new energy coupling control method has stability and strong robustness under various conditions such as different rope lengths, load quality, target position and external disturbance when the initial control force decreases.