Sensor-less and time-optimal control for load-sway and boom-twist suppression using boom horizontal motion of large cranes

Load-sway and boom-twist should both be considered in motion control given that a large crane typically has a long lattice boom. Hence, this study first analyzes the load-sway and boom-twist (vibration) of an actual crawler crane, and proposes a new dynamics model considering the above vibration. To ensure safety, sudden acceleration/deceleration is prohibited while controlling the motion of large crane. In addition, real time measurement and feedback of vibration is generally difficult. Hence, this study proposes a vibration sensor-less control based on a cycloidal motion trajectory with smooth acceleration/deceleration. Two-dimensional load-sway can be suppressed only by boom horizontal motion for simple implementation. Time optimality is also considered in the motion trajectory design in order to ensure operational efficiency. Experimental results demonstrate the effectiveness of the proposed approach. •A new dynamic model considering the elasticity of a large crane is constructed to simulate the crane behavior.•Load sways in the boom turning and centrifugal directions are controlled by using only the boom horizontal motion.•The time-optimal trajectory of the crane that suppresses the vibration of the suspended load is automatically generated.•For the safety and practical applicability, smooth motion trajectory is employed to achieve minimal time and load/boom vibration.•Experimental system was designed and the proposed control was verified by both simulation and experiment.