Adaptive control of the overhead crane by the trolley speed

Abstract

A method is proposed for automatic control of the speed of an overhead-type crane trolley with direct tracking of the horizontal movement of load in conditions of current uncertainty of load parameters and external disturbances. The purpose of the control is to find the precise positioning of the transported cargo with the damping of its pendulum oscillations and the parrying of external disturbances. The dynamics of an overhead crane when moving a trolley along one axis is described. The proposed control method is based on an adaptive control scheme with an identifier and an implicit reference model using «simplified» adaptability conditions. The stability of a closed control system is proved and the conditions for this are determined. For the current identification of load parameters, the recursive least squares method with a forgetting factor is used. This control method was developed specifically for research and debugging on an experimental layout, so all the parameters of the crane and load were approximated to the layout during calculations. The results of computer simulation the proposed control method with different mass-inertial properties of the load, the length of its suspension and perturbations in the Matlab Simulink software environment are presented. The results showed the high efficiency of the proposed adaptive control system. It ensures accurate movement of the load in a short period of time, prevents the load from swinging during acceleration and braking of the cart, and is also able to fend off external disturbances, for example, the impact of wind. The developed approach can be recommended for any crane installations using a suspended load.