In collaboration with EUCENTRE (European Centre for Earthquake Engineering) we have been developing W-TREMORS (Wireless Tremors, vibRations and Earthquake MOnitoRing System), a low-cost wireless sensor platform based on Squidbee sensor nodes.
Our prototype wireless system is easy to program, deploy and integrate with traditional acquisition systems or with existing sensors. Moreover, since software on the nodes has been developed using a simple and high-level programming language derived from Wiring, the behaviour of nodes can be modified also by non-programmers. The coordinator of the whole network is a Koala nano PC, a single embedded computer running Linux. The coordinator collects data from the wireless sensor network and stores all measurements into a database management system (DMBS). The use of a database ensures durability and consistency of collected data; moreover, required samples can be easily extracted and formatted as needed. W-TREMORS application code runs on the coordinator and it provides the user a graphical interface for configuring network parameters. The gateway automatically minimizes also collisions between nodes (and therefore data losses) exploiting a temporal scheduling of transmissions.
The prototype wireless sensor network was tested through shaking test of a steel structure. Data collected from the testbed were used to investigate sampling accuracy and synchronization-related issues. Results show that our wireless platform can effectively monitor seismic events and detect earthquake's effect on civil infrastructures.
All the software needed to setup a working W-TREMORS network is freely available here.
Source code written by Marco Beltrame is released under the GNU GPL License. SQLite is in the Public Domain.