AIRCRAFT head-up displays are being tested in a railway environment using a cab simulator developed by BAE Systems for research into the human factors of train driving. Speed, braking and signalling data are projected onto a small glass screen in front of the driver's face, providing constant access to information without looking down at the driving console and away from the line ahead.
The research is being undertaken using a replica train cab developed by BAE as a cheap way of undertaking speculative research. The global defence technology firm has one of the world's largest Human Factors research departments, and was looking to bring its aviation and defence knowledge into other markets when HF Department Group Leader Kelvin Davies identified a gap in the market for a cheap research simulator. He explains that while high-fidelity simulators from specialist suppliers are needed for safety-critical driver training, the need to accurately represent real cabs generally precludes modifications for speculative research, and high capital costs mean that operators need to maximise the time simulators are available for training.
BAE's cab is intended to be generic, but was inspired by a Virgin Trains Class 390 Pendolino, seen as being typical of current practice. It was built from parts available at high street hardware shops, with the most expensive component being the Grammer driver's seat. Keeping the costs low ensures the simulator is flexible and reconfigurable, and changes can easily be made in-house. 'Safety critical work requires high-fidelity, research doesn't', says Davies.
Under a nine-month study funded by Britain's Rail Safety & Standards Board, 13 drivers from Virgin Trains, GNER and freight operator EWS undertook exercises on the simulator, with their workloads measured using human factors techniques developed for air traffic control design. Workload reductions of up to 10% were seen with 10 of the 13 drivers, and almost all were enthusiastic, though there was no noticeable improvement in performance.
Davies describes Human Factors as 'the science of making sure the requirements of the end user are taken into account', and differences between the air and rail environments soon became apparent. Unlike train design, cockpit design assumes a fixed level for the pilot's eyes. HUD is mainly used when landing aircraft, and there were concerns about the need to keep a train driver's head in a fairly constant position for extended periods. The requirement for displays to remain visible during sudden transitions from bright daylight to dark tunnels is not faced by aircraft.
BAE's research is now looking at the effects of ERTMS, which will present drivers with a much extended range of visual information. Head-up displays would allow drivers to focus on the route ahead while still having data on target speeds and upcoming changes in view.
Consideration is also being g iven to equipping a real locomotive with a HUD for trials next year.
- CAPTION: Experienced drivers tried using projected 'dials', strips based on aircraft controls, and numerical displays, with most preferring traditional dials and rejecting absolute numbers