A new discrete-time approach to anti-swing tracking control of overhead cranes

Motivated by the idea of independent joint control strategy in robot manipulator control field, a new anti-swing tracking control in discrete-time form is presented in this paper. The proposed control system is designed based on a new model where the crane actuators are considered as the main plant. The crane nonlinearities are then considered as disturbances acting on each actuator. The proposed disturbance observer will be able to estimate disturbances and then compensate them via feedforward control. Moreover, robust load swing suppression is achieved through modifying the reference traveling acceleration. The stability analysis of the proposed control system is provided along with experimental results to indicate high performance of the proposed control system against uncertainties such as changes in crane load mass.