Performance Improvement of NCSs Under Complex Network via Concurrent Paths

Different from the single paths between controllers and plants of networked control systems(NCSs), the complex network provides widespread links and brings plenty of paths from the controller side to the plant side. Benefit from this advantage, a novel data transmission dispatching strategy is proposed. When the direct path can not satisfy the condition of system demand, neither stability nor performance, some specified paths compose a concurrent-path to transmit the control signal concurrently. Firstly, the networked control systems(NCSs) are expressed by the switched systems model with the constant network-induced delay, and the network communication is described as a packet-loss process. Secondly, taking system's exponential decay rate as its performance indicator, the relationship between control signal transmission paths and system performance is quantitatively given by considering packet losses as the compound poisson process and the alternating renewal process. Then, due to that different combination of paths induces the different statistical properties of packet losses, the approach to find an appropriate concurrent-path is proposed concerning two mutually constrained factors, the system performance demand and the utilization of network resources. After the theoretical analysis, a distributed communication platform based on peer-to-peer(P2P) network technology is designed and implemented to realize the concurrent-path transmission on internet. Finally, the practical experiment on the platform demonstrates the validity and effectiveness of proposed approach.