New technology to prevent "bus bunching" in London has spoiled the relationship between drivers and passengers, according to new research.
GPS now provides control rooms with real-time information about where each vehicle is, allows bosses to tell staff to speed up or slow down, and in theory puts an end to the phenomenon of three buses arriving at once.
But the commands from superiors sent direct to drivers are putting them under pressure to keep time, to the detriment of passenger service, a study has found.
Researchers from Newcastle University studied the effect of the iBus technology that was fitted to all of the capital's 8,000 buses in 2009.
The technology tells London's 6.4 million users where the next bus is and when it will arrive.
Drivers have to maintain a gap between the services in front and behind, preventing bunching, with live instructions issued direct from the office.
That can lead to drivers rushing, not chatting to passengers and not waiting for them to sit before setting off - or in other cases, deliberating dawdling to eat up time.
In the study, drivers who were interviewed admitted to sometimes "forgoing their usual considerate nature" if the bus behind them was getting too close.
The drivers also told the research team that passengers got frustrated with them for driving too slowly.
One driver said: "There's nothing worse than when you're trying to lose time.
"You can guarantee that the lights will be green and every driver will be absolutely charming. They'll flash to let you out and you're thinking 'No, please go. I'm trying to lose time'."
Presenting their findings today at the CHI conference in Toronto, the team say the technology has fundamentally altered the relationship between drivers and customers.
They said drivers should have more say in the future in how the technology is implemented.
Dr Gary Pritchard, from the university's Digital Interaction Group, said: "Many of these guys have been driving a bus for upward of 30 years and take real pride in their job and the skills it requires.
"So while most of them genuinely want to provide the best service and recognise the benefits of the system, particularly for passengers, some of them also feel threatened by the constant scrutiny and saddened by the lack of social interaction it brings.
"The technology has fundamentally changed the job for bus drivers.
"In conjunction with the oyster card system it has removed interpersonal interaction with the customer and in some cases they feel it has compromised their ability to make safe decisions in relation to speed.
"Ultimately, it means they can't always put customer care and comfort first."
Though some drivers felt the technology de-skilled them, not all saw only negatives.
Dr Pritchard said: "When used in conjunction with CCTV it can support the work of the police and one of the interviewees in the study described bus drivers as 'the eyes and ears of London'.
"But what the findings suggest is that any future systems should grant drivers more autonomy and awareness, supporting them in applying their experience and knowledge of routes while at the same time enhancing the passenger experience."
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