Nonlinear controller for a gantry crane based on partial feedback linearization

This paper presents a nonlinear controller design scheme for a gantry crane system based on partial feedback linearization. In the underactuated gantry crane system, the active degrees corresponding to the freedom are linearized based on I/O linearization techniques, while the passive degree is taken as the internal dynamics of the system. The trajectory tracking control of the linearized system is studied by choosing the active degrees as the system outputs. The analysis of the system internal dynamics shows that the stability of the zero dynamics guarantees the stability of the control system. Finally, experimental results on the scale crane show feasibility of the developed controller design scheme.