On passivity-based trajectory tracking for robotic manipulators combining PD+ and Slotine-Li control

Abstract In this paper, a tracking controller for robots is analyzed, which allows both the specification of the convergence rate of the tracking errors and the parameterization of a desired contact stiffness and damping. It is shown that the control approach can be interpreted as a generalization of the well-known PD+ and Slotine-Li controllers, combining the benefits of both approaches. Although mentioned in the literature before, no thorough theoretical and practical analysis of the aforementioned passivity-based control concept has been performed so far. In this work, the implications of the gains are discussed w.r.t. convergence and interaction properties, addressing possible tuning strategies. Finally, the performance of the controller is evaluated in terms of tracking and interaction experiments on a KUKA LWR IV+.