Non-contact colour sensor counts bogie wheel pulses in rail research project

Working in partnership with the University of Sheffield and funded by the Rail Safety and Standards Board (RSSB), the research project at the IRR involves measuring the ‘creepage’ or ‘micro-slip’ (i.e. the difference between the rail speed and the wheel speed which arises from the transmission of force between wheel and rail) during brake applications
at different coefficients of friction and at speeds of 11mph up to 124mph. 

Understanding the relationship between creepage is critical to optimal and reliable braking performance, particularly for low friction coefficients such as those that occur due to leaves on the line. If excessive creepage occurs traction and braking force reduces, and trains can fail to
meet timetables. In extremes, wheel flats can form during brake application leading to the train being taken out of service for the wheelsets to be re-profiled in a maintenance depot, which is disruptive, time consuming and costly. Having a better understanding of creep force relationship helps to ensure more reliable network operation and a higher operating life
for the bogie wheelsets.

The IRR is a world-leading centre of excellence in the field of railway engineering and risk. Its research has helped to improve the knowledge of the way in which railway vehicles interact with the track, including key performance aspects such as suspension performance, wheel-rail contact, traction and braking. In partnership with industry
and other academic institutes, this work has led to a number of tools and techniques being developed which are now used to predict deterioration of railway wheels and rails, to optimise the vehicle track interface, to increase safety and reliability levels, reduce cost and improve performance of the railway system.

Read the full article in the October issue of DPA.