

Sandwich Node Architecture for Task Preemption in Wireless Sensor Networks for Structural Health Monitoring Applications
Abstract
In recent years, several hardware platforms of wireless sensor networks (WSN) have been developed and used for structural monitoring applications [1,2]. A typical design of a node includes a sensor board and a mote connected to it. Sensing units, analog filters and analog-to-digital converters (ADCs) are integrated on the sensor board and the mote consists of a microcontroller and a wireless transceiver. A WSN system based on this node lacks the capability of interrupting its scheduled task to start a higher priority task. This shortcoming is rooted in the hardware architecture of the node. The proposed sandwich-node architecture is designed to remedy the shortcomings of the existing one for task preemption. A prototype has been implemented using Imote2 and verified by an emulation in which one mote is triggered by a remote base station and then preempts the running task at the other mote for handling an emergency event.