Emergency data gathering with buffer constraint in actuator-based wireless sensor networks

Employing the mobility of actuators to achieve data collection is a challenging problem in the actuator-based wireless sensor networks (AWSNs). The related actuator is usually required to collect the whole information within time delays. However, in practice not all the information need to be collected immediately except the emergencies. In this paper, a mobile emergency data gathering algorithm is proposed on a basis of an improved dynamic shortest path tree. In this algorithm, the dynamic shortest tree is constructed firstly. Subsequently, polling points are chosen to gather data acquired by the sensor network nodes in related sub-regions when considering the transmission hops. Finally, the buffer constraints and emergencies are both taken as key parameters to select a subset of polling points as anchor points for the actuator. The optimal path for the actuator is achieved to minimize energy consumption considering the communication radius. Simulation results demonstrate that this algorithm can promptly response to emergent events and reduce the packet loss with the extended lifetime of network.