The scattering transformation for networked control systems

Communication time delay in a networked control system (NCS) degrades the performance and may lead to instability. For the first time the scattering transformation is applied to NCS in order to guarantee stability in the presence of arbitrarily large constant time delay. This approach, initially derived from network theory and often used in bilateral teleoperation with time delay, requires in its original version all subsystems to be passive. In this paper a stability condition is derived relaxing this restriction such that also non-passive plants can be stabilized. The performance of the proposed approach is superior over two standard approaches, the Smith predictor and PI control in the presence of time delay uncertainties. Experimental validation results are presented