Automatic Obstacle Avoidance Control System for Cable Crane With Error Constraints

ABSTRACT To solve the problem of low efficiency of automatic obstacle avoidance in the operation of cable cranes, this paper proposes a dynamic sliding mode obstacle avoidance control method with an error constraint function. First, considering the geometric position relationship between the trolley and the obstacle, an obstacle avoidance trajectory with an autonomously planned path is constructed based on the sine function, which reduces the excessive requirements for the geometric parameters of the obstacle. Second, a dynamic sliding surface with an error constraint function is designed to control the system's tracking error within a preset range. Finally, the stability of the system is strictly proved by using Barbarat's lemma and Lyapunov's theorem. The simulation results and experiments show that compared with other methods, the controller proposed in this paper reduces the maximum load swing angle during operation, shortens the time required for the load to reach a stable state, and accurately limits the error tracking of the load obstacle avoidance trajectory to within 0.02 m. It also shows good obstacle avoidance performance for external disturbances in the experiment. Therefore, the controller proposed in this paper can complete the obstacle avoidance function of obstacles and achieve accurate positioning and rapid antisway effect of the load.