A supervisory sliding mode control approach for cooperative robotic system of systems

This paper deals with the formulation of a supervisory sliding mode (SM) control approach oriented to deal with the interesting class of system of systems of robotic nature. This class of systems is characterized by the fact of being inherently distributed, cooperative, and, possibly, heterogeneous. In this paper, we propose a modular and composable approach relying on basic modules featuring a multilevel functional architecture, including a supervisor and a couple of hybrid position/force control schemes associated with a couple of cooperative robotic manipulators. In principle, the overall robotic system we are referring to can be viewed as a collection of basic modules of that type. In this paper, we focus on the design of the basic module. The hybrid position/force control schemes therein included are based on position and force controllers. The proposed position and force controllers are of SM type, to assure suitable robustness to perform a satisfactory trajectory tracking even in presence of unavoidable modeling uncertainties and external disturbances. The verification and the validation of our proposal have been performed by simulating the supervisor and the hybrid control scheme applied to one of the two robotic manipulators while experimentally testing the position control on the other arm. The experimental part of the tests has been carried out on a COMAU SMART3-S2 anthropomorphic industrial robotic manipulator.