Applying the brakes with brain power alone

Posted by Kate Taylor

German researchers have used drivers' brain signals, for the first time, to assist in braking, providing much quicker reaction times, they say.

Te system could do a lot to cut the number of car accidents, says the Berlin Institute for Technology - although it won't do much for the driver's image, relaying as it does on electroencephalography (EEG), with electrodes attached to the scalp.

But, says the team, the mind-reading system, along with modern traffic sensors, can detect a driver's intention to brake 130 milliseconds faster than a normal brake pedal response.

Driving at 100km/h, this amounts to reducing braking distance by 3.66 meters - the full length of a compact car, or the potential margin between causing and avoiding accidents.

As well as EEG, the researchers also looked at myoelectric (EMG) activity, which is caused by muscle tension in the lower leg and can be used to detect leg motion before there's actually any movement.

Participants in the study carried out a driving simulation at 100 km/h. They were asked to stay within a 20 meter distance of a lead vehicle on a road with sharp curves and dense oncoming traffic.

At random intervals, emergency braking situations were triggered by the rapid braking of the lead vehicle in front, accompanied by the flashing of its braking lights.

At this point, when the subjects reacted, the data was collected from the EEG and EMG. For comparison, the researchers also recorded information on the time it took to release the gas pedal and press the brake pedal, the deceleration of both vehicles and the distance between them.

"Averaged over all potential detection thresholds, a system that uses all available sensors detects emergency situations 130 milliseconds earlier than a system that doesn't use EEG and EMG. We can safely say that it is mainly EEG that leads to the early detection," says lead author of the study Stefan Haufe.

"We are now considering to test the system online in a real car; however, if such a technology would ever enter a commercial product, it would certainly be used to complement other assistive technology to avoid the consequences of false alarms that could be both annoying and dangerous."