Network-based controller adaptation based on QoS negotiation and deterioration

Networks and their applications have been evolving substantially in the last two decades. A new and promising use of networks is in the area of high performance control and automation, which is developing into attractive and widespread applications. Some of the major concerns in using networks to perform remote network-based control are QoS issues such as time delay and bandwidth constraints. Disturbances and unanticipated events often happen to network-based applications. When anomalies happen, if the network cannot provide the required QoS, the application may have to lower its performance requirement and use the assigned QoS to do the best as it can to maintain the application availability. This paper proposes the use of real-time application gain adaptation to compensate for QoS variations and deterioration. A numerical and an experimental simulation of a network-based controlled DC motor are used in this paper to illustrate the effectiveness of the proposed scheme.