A steering system for use on guided buses or rubber-tyred trams, which incorporates an automatic safety mechanism, could speed the adoption of the vehicles in UK towns and cities.
The Safeguide system senses low-voltage signals generated by a pair of cables buried under the road.
But buses using wire guidance technology have generally fallen foul of the Railway Inspectorate, which approves such vehicles, said Martin Pemberton, managing director of the system’s developer, Warwickshire-based Transport Design International.
‘For a system like this to be acceptable to the Inspectorate it has to fulfil certain requirements – the Inspectorate is not so much concerned with how the system works, but what happens when it doesn’t work,’ he said.
The Inspectorate insists on wide safety margins at the sides of guided buses, in case the vehicle loses contact with the guidance system and the driver has to intervene, meaning driver reaction times must be taken into account. This led Transport for London to abandon plans for a guided bus route on the Millennium Transit between south-east London and the Dome.
So after discussions with the Inspectorate, the company has developed a secondary steering system, designed to automatically take over from the primary system should a problem arise. This constantly monitors the health of the primary system, and if it senses a loss of signal, shuts down and brings the vehicle safely to a halt.
While the system could be applied to any rubber-tyred vehicle, it was developed as a result of TDI’s work into building the Minitram, a lightweight electric vehicle narrow enough to travel through some of the UK’s oldest towns and cities.
The zero-emission vehicle, which costs less than £1m per km to install, underwent successful trials in Stratford-upon-Avon last year, and Warwickshire county council has agreed to buy an initial three Minitrams, which TDI hopes to have running by the end of this year.
TDI has also been commissioned by Coventry city council to carry out a trial of Minitram with the Safeguide system next month.
Bus and train operator FirstGroup announced this month it plans to introduce rubber-wheeled trams next year, although the company has no prototypes as yet. ‘FirstGroup is talking the samelanguage as us. It could be a potential customer,’ said Pemberton.
Safeguide was developed using funding from Nesta, the National Endowment for Science, Technology and the Arts.