A higher order sliding mode control for cooperative systems with unknown time-delay

In this paper, a robust teleoperation with multi masters/multi slaves in the presence of uncertainty in robot dynamics is presented. To grasp an object safely and regardless of communication-delay, the slave robots are decomposed to the so-called locked and shape systems with preserving passivity. Higher order sliding mode controllers are designed to control shape and locked systems. Towards this end, wave variable based communication is used to overcome the master-slave communication-uncertain delay. By employing the passivity property of the decomposition and wave variable based communication, energetic passivity of the closed-loop system is ensured, and, interaction stability and safety are improved significantly. The provided simulation results show anacceptable performance of the cooperative system.