⦁ Low-cost wireless sensor node

This a wireless sensor node developed for structural health monitoring of civil infra structures. The developed sensor node is capable of sensing ambient vibrations in
terms of accelerations. The sensors mounted in each node are capable of
measuring very small vibrations (1 mg range). The communication between each node was
established using wireless network protocol, sub-1 GHz (Radio waves) which is very efficient
in terms of long-range communications, power consumption and penetration through
obstacles. When it comes to collecting data using wireless sensor networks, there are inherent
challenges such as time synchronisation, scalability, packet handling (collision), packet loss,
data storage, power consumption etc. However, accuracy of time synchronisation was
identified to be the most crucial problem as far as interpretation of results is concerned. During the laboratory test it was found that the synchronization error was within the allowable limit. Also, the developed Wireless sensor network
was checked for its performance in laboratory level and accelerometers were calibrated using
shaker table which has accurate analog sensors and digital accelerometers which are already
calibrated in laboratory level. The product is made using off the shelf products such as Raspberry PI, CC1310 and powerful antennas. The Algorithm developed and implemented was proved to be effective and the complete WSN developed was established on a target building to observe the insitu performance and the performance was satisfactory.