Second order sliding mode real-time networked control of a robotic manipulator

The distributed control of industrial plants, where the control algorithm runs on a machine that receives information from sensors and sends actuation commands over a communication network is a challenging task, due to the delays introduced by communication. This paper presents the networked control of a robotic anthropomorphic manipulator based on a second order sliding mode technique. The control objective is to track a desired trajectory for the manipulator. The adopted control scheme allows an easy and effective distribution of the control algorithm over two networked machines. While the predictability of real-time tasks execution is achieved by the S.Ha.R.K. real-time operating system, the communication is established via a standard Ethernet network. The performances of the control system are evaluated under different experimental system configurations using a COMAU SMART3-S2 industrial robot, and the results are analyzed to put in evidence the robustness of the proposed approach against the possible network delays.