This article develops state-dependent parameter (SDP) control systems for the hydraulically actuated manipulators of a mobile nuclear decommissioning robot.
The state-dependent variable is a delayed voltage signal associated with the time-varying gain of the system. The latter can cause undesirable joint movements when the device is regulated using linear control algorithms. For the preliminary experiments reported here, the basic SDP algorithm (which requires stability assessment by simulation) is utilised, since this is simpler to implement than some alternatives. Nonetheless, experimental data shows that the SDP design more closely follows the joint angle commands than the equivalent linear algorithm.