Distributed Collaborative Processing under Communication Delay over Wireless Sensor and Actuator Networks

Abstract: In wireless sensor and actuator networks (WSANs), the sensor nodes are involved in gathering information about the physical phenomenon, while the actuator nodes take decisions and then perform appropriate actions upon the environment. The collaborative operation of sensor and actuator nodes brings significant advantages over WSNs, including improved accuracy and timely actions upon the sensed phenomena. However, unreliable wireless communication and finding a proper control strategy cause challenges in designing such network control system. In order to accomplish effective sensing and acting tasks, efficient coordination mechanisms among different nodes are required. In this paper, the coordination and communication problems in WSANs are studied. First, we formulate the mathematical models for the WSANs system. Then, a predictor-controller algorithm based on distributed estimation is adopted to mitigate the effects of network-induced delay. Finally, we apply a collaborative processing mechanism to meet the desired system requirements and improve the overall control performance. This approach will group the sensor and actuator nodes to work in parallel so as to reduce the computation complexity and enhance the system reacting time. Simulation results demonstrate the effectiveness of our proposed method.