Switching-based emergency braking control for an overhead crane system

Emergency braking plays an important role in the safety of overhead crane systems; however, it has received little attention so far. Motivated by this fact, two practical guidelines for the emergency braking control of overhead crane systems are proposed, which are safety and efficiency in brief. Based on the guidelines, a novel two-stage switching control strategy is then presented to improve operation safety. Specifically, at the first stage, a braking controller is exerted on the trolley to prevent the payload from moving forward as soon as possible. At the second stage, an energy-based damping controller is adopted to stabilise the overall system rapidly. These two controllers are switched automatically and the switching time is selected carefully to ensure satisfactory control performance. Both simulation and experimental results are presented to demonstrate the effectiveness of the proposed braking control method.