Safe Speed Forums

Brake assist systems - which apply full braking power during emergency stops even if the driver doesn't push the pedal hard enough - may become mandatory on all cars sold from 2008 onwards. That's one possible alternative to phase two of the European Commission's rules on pedestrian safety.
Phase one comes in at the beginning of October this year, and isn't part of the argument. Phase two - which involves increasing the crush zone between the front of a car and its engine and radiator, and is described in some quarters as "not technically feasible" - is due to start on a 1 September 2010. The use of brake assist is being put forward as a more reasonable alternative.
"We always said active safety is better than passive," says Alfredo Filippone of the European car manufacturers group ACEA. "It's better to try to avoid the collision in the first place."
There is agreement to this within the Commission. A spokesman has revealed that during a study conducted last year it was established that using brake assist in conjunction with active collision avoidance systems would create the same safety benefits as intended by the current phase two rules.
Radar-based brake assist is already available on cars such as the Audi A6 and A8, and supplier Bosch says that a system which will jolt the brakes to warn the driver that an emergency stop may be required shortly will be on the market late next year. More sophisticated systems - which can detect an object, realise that the driver isn't going to react quickly enough and perform the emergency stop on their own - may be only a few years away, according to Siemens VDO Automotive, though as spokesman Enno Pflug points out, "an object detector needs a lot of computing power to detect a pedestrian."

Or I'm attempting to do some finely balanced braking on a bend with a hazard ahead, and all of a sudden the car decides to do a full on emergency stop?

Or I'm scrubbing off speed with strong braking in an emergency, planning to steer to safety once enough speed is gone, but the car decides to carry on braking for too long?

Or the poxy control computer crashes and applies full braking in L3 of a busy motorway for no apparent reason?

And what on earth is it going to do on ice? Detect the onset of wheel lock and decide it must be an emergency? I hope not.

obviously these are safety critical systems with requirement for a high safety integrity level. the hardware is the same as ABS/ESP so its a well tried and tested bit of kit.

Speaking as an electronic engineer, it is utterly impossible to crash-proof any microprocessor based system.

With ABS, I believe that the control unit only has the power to demand a brief interruption of brake force.

Presumably it would not be too difficult for an experienced driver to disable these systems if he/she didn't like them, in the same way that ABS and air bags can be disabled if required.
With the current very low levels of speed at which we are now allowed to drive, I really can't see the need for any of this new kit.

"It's better to try to avoid the collision in the first place."says Alfredo Filippone of the European car manufacturers group ACEA.

How would a system such as EBA cope with 'interference braking' for instance?

Presumably it would not be too difficult for an experienced driver to disable these systems if he/she didn't like them, in the same way that ABS and air bags can be disabled if required.
With the current very low levels of speed at which we are now allowed to drive, I really can't see the need for any of this new kit.

Some of this techology is quite fascinating but I'm not sure it is all being used wisely. I think the balance between technical progress and the average quality of drivers is deteriorating. The best results IMHO will be obtained by improving the most comprehensive and versatile control mechanism of all - namely a properly competent driver.

"We always said active safety is better than passive," says Alfredo Filippone of the European car manufacturers group ACEA. "It's better to try to avoid the collision in the first place."

There are other safety concerns too:

1) Does it take road adhesion (e.g. wet, icy etc) into account when determining the braking force?

2) There are certain situations where crashing into the back of someone is preferable to losing control and ending up in the path of oncoming traffic. How can a computer make this decision?

I was once the victim of the EBA system in my Dad's E-Class. A well-hidden gatso took me by surprise. Even though I wasn't speeding, I instinctively moved my foot to the brake pedal. I only touched it very lightly and I ended up doing an unintentional emergency stop.