Design of a Novel Switching Controller for an Industrial Crane System

Sliding mode control is a powerful method for addressing uncertainties in nonlinear dynamic systems. This paper presents a comprehensive analysis, redesign, and comparison of different sliding mode controllers for an industrial crane system that transports underwater objects. To improve the stability of the system and reduce or eliminate chattering, a family of continuous switching functions was applied during the redesign of the switching control part. A comparative study of these proposed functions was conducted to evaluate their performance criteria in two separate stages: the optimal gain-finding stage and the ideal shaping coefficient-identifying stage. In order to validate the efficiency and robustness of the newly designed controllers, numerical results obtained using both the novel and the traditional approaches were processed using statistical metrics and compared. As expected, the new sliding mode controllers delivered excellent simulation results for the crane system and exhibited minimal visible chattering as well as tracking errors. Moreover, a set of optimal feedback gains for the switching control part was determined, and an ideal shaping coefficient for each continuous switching function was found.