Globally Stabilizing Motion Control for Robot Manipulators With Bounded Inputs Through a PD+ Type SchemeWith Saturating-P and Saturating-D Actions

In this work, a globally stabilizing bounded controller for the trajectory tracking of robot manipulators with saturating inputs is proposed. It may be seen as an extension of the so-called PD+ algorithm to the bounded input case. With respect to previous works, our approach gives a global solution to the problem through a static controller. Moreover, it is not defined using a specific sigmoidal function, but any one on a set of saturating functions. Furthermore, the bound of such functions is explicitly considered in their definition. Hence, the control gains are not tied to satisfy any saturation-avoidance inequality and may consequently take any positive value. The efficiency of the proposed scheme is corroborated through numerical simulations.