NeTS: Small: Real-Time Wireless Sensor-Actuator Networks

Washington University, Saint Louis MO

Investigators

Abstract

Recent years have witnessed rapid adoption of wireless sensor-actuator networks (WSANs) in process industries. Real-world deployments of industrial standards such as WirelessHART have demonstrated the feasibility to achieve reliable wireless communication in industrial environments. However, existing wireless technologies still face significant challenges in supporting process control applications that impose stringent real-time requirements on network communication. Moreover, optimizing control performance over wireless networks is challenging due to the coupling between control performance and communication delays, as well as inter-dependencies among multiple layers of the network protocol stack. To meet these critical challenges faced by process industries, this project is developing a control-aware network design approach for WSANs. This holistic approach integrates wireless networking, real-time scheduling and non-linear optimization in a unified framework with three novel technologies: (1) an efficient local search approach that leverages real-time scheduling analysis to optimize control performance over wireless networks; (2) an agile multilayer optimization approach that adapts transmission scheduling, routing and sampling rate selection in a hierarchical fashion in response to network changes; (3) a hierarchical network architecture that enables large-scale real-time wireless control networks. The project implements and evaluates the network architecture and protocols using realistic industrial process control applications on physical wireless testbeds through collaboration with Emerson, an industrial leader of the WirelessHART standard. Successful completion of this research will enable a broad range of process control applications with high societal and industrial impacts such as oil refining, petrochemicals and water treatment. Collaboration with industrial partners will lead to real-world deployments and technology transfer to process industries through industrial standards. This research will produce an open-source implementation of the real-time wireless protocol stack, which will further broaden the impacts on research, education and industry.