It has long been a joke among Londoners that you wait 20 minutes for a bus, then three come along at once.

But that could become a thing of the past if Transport for London’s (TfL) £117m upgrade of its bus communications systems is a success.

At the end of this month TfL will complete passenger trials of the iBus system on the 149 route (Computing, 2 February). And next year, working with IT contractor Siemens, the organisation will begin installing the technology on the 8,000 buses that run across 700 London bus routes.

Key to the project will be a switch from tag and beacon technology that records the location of the bus when it passes roadside beacons along the route, to real-time satellite tracking.

Onboard computers using GPRS mobile technology will feed back the bus’s location to central co-ordination systems every 30 seconds, meaning operators can monitor their fleet more accurately and prevent services from bunching up.

‘Drivers will have the ability to see their position in terms of the bus in front and behind, so that they can keep their distance,’ said Martin Davey, iBus project director at TfL.

By replacing the beacons, which are attached to lampposts and other roadside objects, TfL will also be able to reduce maintenance costs.

‘The beacons get knocked, vandalised and blocked, so there are big availability and maintenance cost issues that will be overcome,’ says Davey.

The automatic vehicle location project, one of the largest in the world, will also deliver benefits for passengers in transit. Audio and visual announcements will tell passengers the name of the next stop and, where relevant, information about underground stations and attractions such as major tourist sites.

If a bus has to be diverted because of roadworks or an incident, the communications system alerts the driver and provides an alternative route.

iBus will also bring with it extra safety features. Video images from onboard CCTV cameras will be transferred over a wireless broadband connection to a central TfL database when buses arrive at a depot.

The communications system will also link to CentreComm, a control centre manned by police and TfL staff in Victoria.

‘If an emergency happens the bus will send its co-ordinates to CentreComm, which are immediately transferred to a graphic display so they can pinpoint where it is,’ says Davey.

Bus drivers can also use the system to send pre-recorded messages to the control centre, reporting crimes or traffic accidents they see on the streets.

TfL has ambitious plans to complete the rollout of the iBus technology to all its buses in 2009. It will then consider other uses for iBus, such as alerting commuters via mobile phone when their bus is due or delayed.

‘Passengers will be able to receive information about their bus route,’ says Davey.

iBus ...in 30 seconds

Why is TfL upgrading its bus communications system?

*More than 8,000 buses serve 6.3 million passengers a day, on a network originally designed for 4,500 buses.

*Routes have expanded to the outer areas of the capital, where it is hard to use existing radio systems.

*TfL’s 5,000 bus-monitoring beacons are prone to accidental damage, vandalism and obstruction. Satellite tracking reduces maintenance costs and is more accurate.

*London’s tourist trade and growing multiculturalism has led to increased demand for visual and voice announcements on buses.

*Using messaging systems, bus drivers can report suspicious incidents and crimes they see occurring on their route.

*TfL can better monitor the performance of 15 private firms that run routes in London.

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