Solving the Adhesion Riddle:
Towards a high resolution ‘Internet of Things’
moisture detection system for railways
Dr Lee Chapman
Reader in Climate Resilience
Birmingham Centre for Railway Research & Education
University of Birmingham, UK
l.chapman@bham.ac.uk
Why improved moisture detection?
• High resolution forecast systems for low adhesion now exist
– Facilitate mitigation of adhesion through better, targeted
operation of Rail Head Treatment Trains in areas where
adhesion is predicted to be low.
– Justify actions to alter ‘plans of the day’ when forecast
conditions change.
– Enable special time tables to be removed on good days or in
areas where adhesion is predicted to be good thereby
improving performance.
• Q1: How can they be verified to improve user confidence?
• A: High resolution (low-cost) moisture measurements.
– Can also feed directly into Adhesion Management Systems
• Q2: How can this be done?
The Internet of Things
• Literally means things that
connect to the internet
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Computers
Smart Phones
Curtains, lights, central heating...
Sensors
• AutumnSense inspired by a sensor developed by
the University of Birmingham for an urban heat
island project
• Bespoke self contained air temperature sensor
was designed to produce a high resolution
network across the city:
– Comms provided via a wireless communication card
– Power provided from a Lithium-Thionyl Chloride battery
which last for 3 years under ideal conditions
– Very cheap - £87!
– Tested at UKMO calibration lab with an absolute error of
±0.22°C
• Can be deployed anywhere where there
is a WiFi network
Low Cost Moisture Sensors
• Same low cost technology (<£100) now modified for use on this
project
• Thermistor replaced with a leaf wetness sensor to be attached to
a dummy rail
• Various options for data collection
– Local logging on device (10000 points on flash memory)
– Accessed locally via smartphone in real-time
– Sent over internet remotely to server at University where it is
archived
Laboratory Tests
Field Trial
Next Steps
• Successful trial but now there is a need to:
– Deploy a small network of sensors within a resilient Wi-Fi
network to fully demonstrate the potential of the approach.
– An extended trial over a longer time period is required
– Continued funding to investigate and
improve trackside internet connectivity
(e.g. 700Mhz T795). Whilst the benefits
of this extend beyond sensor networks,
the availability of a wireless mesh will
facilitate not only the widespread
moisture measurements discussed but
also other condition monitoring data
such as temperature.
– Continued dialogue with the industry to
ascertain the exact requirements of a
high resolution adhesion detection system
Questions?
Dr Lee Chapman
Reader in Climate Resilience
Birmingham Centre for Railway Research & Education
University of Birmingham, UK
l.chapman@bham.ac.uk