Abstract:  Aiming at the difficulty of rotating and positioning the load around the hoisting line when the crane was working, an attitude control method of the suspended load system was proposed based on the law of conservation of angular momentum with the momentum wheel as the actuator. Firstly, the mechanism and structure of the suspended load system were studied, the kinematic equations of the system were deduced by the Euler angle description method, and the dynamic modeling of the system was carried out based on the law of conversation of angular momentum. Then, the stability of the system was studied, and the proportional-integral and proportional-derivative (PI+PD) mixed control law was used to complete the pitch direction rotation position control, and the proportional-derivation (PD) control law was designed to suppress the shaking caused by external disturbances to the pitch direction rotation. The simulation experiment of the system under wind disturbance was carried out based on the Simulink environment of MATLAB. Finally, a prototype experimental platform was built, the actual process test was carried out, and the simulation results were verified by combining the test results. The research results indicate that the designed control law is effective, the position control angle error reaches the order of 10-2. The problem of difficult load rotation positioning is solved, and the sway of pitch direction rotation caused by external interference is restrained.
Key words:  self-propelled crane; momentum wheel; conservation of angular momentum; proportional-integral and proportional-derivative (PI+PD) mixed control; attitude control method