Event-based control as a cloud service

Event-based control has gained significant interest from the research community in recent years because it allows better resource utilization in networked control systems. In this paper, we propose an architecture for offering event-based control as a service from the cloud, which not only improves resource utilization but also reduces the cost and setup time of large-scale industrial automation systems. Providing event-based control from the cloud, however, poses multiple research challenges. We address two of the main challenges, which are the network delays and failures introduced because of moving the controller far away from the plant. We present a delay mitigation technique that maintains the stability and performance of the control system. Our results using commercial clouds show that our delay mitigation technique can handle large communication delays up to several seconds with practically zero effect on the main performance metrics of the system. Moreover, our proposed fault tolerance approach can effectively handle network failures even if the controlled system is thousands of miles away from its cloud controllers.