Design of a Gain-Scheduling Anti-Swing Controller for Tower Cranes Using Fuzzy Clustering Techniques

The main objective of this paper is to design a fast, non-expensive and practical controller for tower cranes. The controllers are designed to transfer the loads from point to point, as fast as possible, and at the same time the load swing is kept small during the transfer process. Moreover, variations of the system parameters such as cable length are taken into consideration. It is shown how the state feedback controllers along with the gain scheduling could be used for a time varying linear model with varying parameters. For this reason, linear controllers are designed for a number of operating points, where their parameters are interpolated for conditions in between. In this way, a globally nonlinear controller is obtained. However, the selection of the operating points and the design of the interpolation scheme remains a time-consuming procedure. In order to reduce the design efforts, an automated procedure for determination of the number of operating points and their locations using fuzzy clustering have been proposed. This approach also provides the interpolation mechanism, using membership functions, for the local controller parameters.