Command shaping for vibration reduction of container cranes

A combination of command shaping and bang/off-bang control scheme for container cranes is investigated in this paper. A linear model of the system is used to design the input shaper, where the trolley acceleration is given as an input, for suppressing the payload vibration. Bang/off-bang control guarantees that the trolley reaches the goal position By utilizing an industrial servo motor and its driver, the acceleration command from input shaper is integrated to become the velocity command for the motor. The control algorithm is simulated with the nonlinear system. The robustness of the control system is also evaluated with the natural frequency has ± 10% uncertainty (rope length variation).