Experimental comparison of nonlinear controllers for flexible joint manipulators

Presents an experimental comparison between four nonlinear controllers for flexible joint manipulators. These control inputs theoretically guarantee global tracking of any admissible reference trajectory. The experimental set-up is a 2-degree-of-freedom (DOF) manipulator, with an elasticity at the second joint. This work follows and confirms a previous comparative study based on theoretical and numerical investigations. The main conclusion of the work is that some controllers may behave quite differently when applied to a particular device, despite of their apparent theoretical resemblance.