Abstract:
Majority of people in India depend upon railways as their mode of transportation. It is
very important that railways are made safer to travel. Recently, there have been a few
accidents due to poor maintenance of the tracks and coaches. Manual monitoring and
regular inspection of railway lines and coaches by skilled labour is very time consuming
and expensive. Wireless sensor networks (WSNs) have the capability to address these
issues. With WSN deployed in rail coaches, they can continuously monitor the interaction
of the coach with the rail lines. This data can be analysed to nd out precise faults in real
time and hence can make maintenance more a ordable and e ective. One of the threats
to WSN is the limited battery life of the sensor nodes. The battery in nodes needs to be
recharged/replaced frequently. This thesis proposes a battery boosting device that can
increase the usable lifetime of the nodes as well as the network.
This dissertation proposes hybridization of medium access control (MAC) protocols
based on the tra c conditions. The WSN switches between two existing protocols i.e.
EA-TDMA and E-BMA depending on whether there is medium to high or very high
tra c respectively.
Data tra c in a WSN depends on the rate at which the data is sampled and trans-
mitted over the network. Keeping a xed sampling rate may lead to oversampling when
the train is moving at low speed. To overcome this limitation, this dissertation proposes
a speed dependent sensor sampling method.
The three aforementioned techniques are implemented in hardware to test the per-
formance in a practical WSN environment. It is found that the combination of three
approaches can increase the lifetime of sensor nodes by approximately 30% in real-time
scenario.
