Safer driving?

A pedal that works as both an accelerator and a brake will save lives if car makers adopt the design, according to Swedish inventor Sven Gustafsson. The idea sounds bizarre, but officials at the Swedish National Road Administration have already done extensive road tests and approved the device for use.

It takes longer to brake in an emergency with separate pedals, says Rickard Nilsson at Uppsala University, who tested out Gustafsson’s pedal for the SNRA. It takes at least 0.2 seconds to move your foot from one pedal to the other, he says, and at 90 kilometres per hour this adds five metres to your stopping distance. Another problem with separate pedals is that it’s easy to hit the wrong one. A slight misjudgement when going for the brake, perhaps because a driver is wearing a new pair of shoes, can lead to the accelerator being clipped, causing a crash.

With Gustafsson’s combined pedal you have to make two distinct motions for accelerating and braking, and you can’t do both at the same time. To accelerate you pivot the pedal, while to brake you push the entire pedal mechanism forwards. So accelerating is predominantly an ankle movement, while braking comes from extending the whole leg. ‘You can go from acceleration to braking instantly, just by pressing the combined pedal forwards,’ the inventor says. ‘As soon as you brake the accelerator is switched to idle.’

It’s not the first time the pedals have been rearranged. Henry Ford was the first to introduce the three-pedal car in 1909. His Model T`s accelerator was a lever on the steering column, while the three pedals were a brake, a gear shift and a clutch. Ford later decided that the brake and accelerator should be placed close to each other and operated alternately. By 1928, the Model A had an accelerator pedal and a separate gear control. Automatic transmissions later made the clutch obsolete.

Gustafsson, who hails from the southern Swedish city of Lund, pondered the combined pedal idea for 30 years, but has only just got around to developing it. Now his idea could lead to manual cars with two pedals and automatics with just one. Since the SNRA approved it, he and his wife have been driving their car with one-with no problems.

During his evaluation for the SNRA, Nilsson tested how well drivers adapted to the combined pedal. He set challenging driving tasks to assess the abilities of 18 people before and after they drove about 1000 kilometres with the combined pedal. They took the tests in cars with the combined pedal and with conventional pedals. ‘They relearn very fast and without very much effort,’ he says. But Nilsson is worried that drivers using the combined pedal may become accustomed to their improved reaction time and drive more recklessly.

Besides improving normal reaction times, Nilsson believes that the combined pedal could also make cruise control functions safer. Cruise controls allow drivers to set a desired speed for long journeys so they can take their foot off the accelerator and rest it. But because the combined pedal lets the driver rest their entire foot on the pedal while cruise control is activated, they should be able to react to emergencies far quicker.

Volvo is testing the pedal in cars, buses and trucks. But a mass-produced version won’t be available to motorists for at least three years, even if manufacturing approval is granted straight away.