LPV observer design and damping control of container crane load swing

This paper presents advances in the damping of container crane load swing via hoisting modulation based on linear parameter-varying (LPV) control techniques. We propose controllers based on constant, as well as parameter-dependent Lyapunov functions and formulate our problem in the linear fractional transformation (LFT) framework. The dynamics of a nonlinear observer are included into the generalized plant. Simulation and experimental results are compared to previous work using a polytopic LPV approach, as well as to earlier work based on the concept of resonant coupling control realized by a reduced normal form approach. The comparison indicates, that including the observer dynamics in the synthesis comes at the price of reduced performance, which is alleviated by the use of parameter-dependent Lyapunov functions. Furthermore, an a posteriori analysis verifies that the controller is robust against erroneously estimated scheduling signals and thus provides closed-loop guarantees for stability and performance for the new controller.