Identification-based speed control of an overhead crane with a reduced cargo transfer model

This paper considers an automatic control approach for an overhead crane trolley under the current parametric uncertainty of the crane, transported cargo, and exogenous disturbances. It generates a given trolley speed, which corresponds to the modern hardware implementation of control of cranes with asynchronous motors and frequency converters. The approach is based on a control scheme with a current parametric identification algorithm, an implicit reference model, and “simplified” adaptability conditions to track cargo movements directly. This algorithm involves a recursive least-squares method with the forgetting factor. Unlike previous publications on the topic, the idea is to use a reduced model of the “crane–cargo” object when moving the cargo along one horizontal axis. In this case, it is necessary to estimate only two parameters; moreover, the construction of the control algorithm becomes simpler and the closed-loop control system has a better performance. The stability of the closed-loop control system is proved and requirements for the parameters of the assigned reference motion are found. Due to the self-tuning property of the control system, the approach can be obviously generalized to construct an overhead crane control system along two horizontal axes and three axes (with simultaneous vertical movement of the cargo). A model example is given to demonstrate the implementability of this crane control system based on modern controllers and sensors.