20 replies to this topic

[cjpani]

Someone found this on his office intranet (autoliv i think)

Honda Develops Automatic Collision Prevention System

(22 May 2003) TOKYO --According to newswire reports, Honda Motor Co. said Tuesday it has developed what it claims is the world's first system that predicts collisions and assists brake operations to reduce damage to occupants and vehicles.

The ''collision mitigation brake system,'' which was made feasible amid intensifying competition among major carmakers to develop similar technology, will be introduced in new versions of its Inspire sedan set to be launched in June, Honda said.

The system features a millimeter-wave radar that detects vehicles ahead within a range of 100 meters and calculates the distance between the vehicles, the relative speeds and the anticipated vehicle path to determine the likelihood of a collision, it said.

In the primary warning, when the system determines there is a risk of collision or if the distance between the vehicle ahead has become too short, a buzzer sounds and a message for braking appears on a display to ''prompt the driver to take preventative action.''

If the distance between the vehicles diminishes further, light braking is applied and the seat belt is retracted gently two or three times to provide the driver with a tactile warning.

Then, if the system determines a collision is unavoidable, the seat belt is retracted ''with enough force to compensate for seat belt slack or baggy clothing'' while the brakes are activated forcefully to further reduce the speed of impact, Honda said.

A Honda spokesman stressed that the newly developed system ''is designed essentially to help prevent collisions and it doesn't mean drivers don't have to do anything.''

It sounds dangerous; as i believe that heavy braking is not always the best way to avoid an accident; maybe swerving, or even accelerating...

What do you make of this?

cj

[alexbiker]

Would require some serious software!

So you're crusing along on the motorway, fast lane, 100mph, and someone chops into the small gap in front of you. Transiently, the closing speed will be high even if they're going at the same speed, since they're travelling at an angle to you, and the distance between you and him (always a him, doing something like that, probably driving a BMW ) is very small.

Then, the person behind gets a serious surprise as a metaphorical anchor flies out of your window for no particular good reason.

Plus, most motorway accidents happen when something goes wrong inside your braking distance, and you're too dopey to avoid the hazard. The causative danger is not that people don't apply their brakes - it's rare people plow straight into the back of each other without braking at all - but that they put themselves in an inescapable situation.

Most of the time, they get away with their situation. But as my driving instructor pointed out, people crash when two things go wrong. You're usually fine, driving dangerously, but one time something extra happens, and you can't cope. I doubt auto brakes will make much difference.

Although I doubt the braking aspect will prevent many crashes (I'm sure it will cause more than it prevents), the seatbelt pre-tensioning might save the odd ruptured spleen, fractured sternum and broken collarbone, and maybe even a death or two.

Although the Americans, if they really cared, could make seatbelts mandatory nationwide.

Alex

[bira]

Mercedes launched a pedestrian detector on their cars this year, which does effectively the same thing (to avoid hitting an unexpected stray pedestrian ).

[alexbiker]

Yes, for the S-class. Although I'm surprised really - the average S-class occupant may not be that bothered about the peds. Might only fit it to save on bumper repair.

Joking!

Alex

[wegmann]

Originally posted by alexbiker

Although the Americans, if they really cared, could make seatbelts mandatory nationwide.

I think almost all the states have mandatory seatbelt laws now, if you consider that "caring".

[alexbiker]

Not all, and it's becoming a bear on sports car designers' backs that they must start to include curtain airbags on cars above the sun visors, which would be pointless if occupants were wearing seatbelts.

These are becoming a requirement for new cars, and the best technologies mean a 3 inch raising of the roofline. Doesn't sound a lot, but it's a major pain - it makes the roofline of the Aston Martin DB7 impossible.

This is a crime I may never forget. Changing the lines of the most gorgeous car currently made.

Just wear a seatbelt! The beauty! Think of the beauty!

Alex

[Tumppi@BXL]

Originally posted by alexbiker
[B]Would require some serious software!
Plus, most motorway accidents happen when something goes wrong inside your braking distance, and you're too dopey to avoid the hazard.

Don't remember all the figures from the top of my head, but in Europe:
40.000+ road fatalities per year
90-95% of these, driver error is primary or secondary cause of accident
less than 5% of fatalities occurr in the motorway

So, the high-speed, dual-carriageway stuff is not what these preventive safety applications are designed for, but single-carriageway accidents at speeds of 70-110kmh. It's not only a single application in vehicle doing the distance calculation that makes this stuff work and save lives. There are things like vehicle-to-vehicle information propagation (so the vehicle behind you knows your car will be instructing you to brake in 5secs, the oncoming vehicle telling you there is an accident on your lane 2km from here), automatic standardised emergency calls with vehicle information from vehicles to the 112-call centres, more intelligent road infrastructure, driving speed alerting and controlling and so on and so on. If you can think of it, someone probably is already designing it.

The whole vehicle safety issue is a hot potatoe in Europe currently - a political target being to cut down the fatalities to HALF by 2010. And, all the electronic gizmos (be they, pre-, during- or post-crash) are an issue the vehicle manufacturers are pouring hundreds of millions of euros into. And they're not talking about having these as options to luxury vehicles - it'll eventually go through the whole model range from the Twingo/Lupo to the Velsatis/Phaeton or whatever they'll be called by then.

And the F1-link of all this? ...Well, Max Mosley is one of the drivers of all this with the EuroNCAP background and all of the FIA....

Truly interesting, if even one tenth of the stuff that the vehicle manufacturers are cooking up on safety comes to the market, your average road car will be very different by 2010!

[MrBreaker]

Originally posted by alexbiker
Although the Americans, if they really cared, could make seatbelts mandatory nationwide.

Alex

Alex, I'm pretty sure that all states require you to wear a seatbelt. Actually, I think it's a Federal law. We have these weak ads on TV saying "Click it or ticket!". Since the ad doesn't mention a particular state, I can only assume that it's nationwide. But you know what they say about assumptions.

[wegmann]

Originally posted by alexbiker
Not all, and it's becoming a bear on sports car designers' backs that they must start to include curtain airbags on cars above the sun visors, which would be pointless if occupants were wearing seatbelts.

These are becoming a requirement for new cars, and the best technologies mean a 3 inch raising of the roofline. Doesn't sound a lot, but it's a major pain - it makes the roofline of the Aston Martin DB7 impossible.

This is a crime I may never forget. Changing the lines of the most gorgeous car currently made.

Just wear a seatbelt! The beauty! Think of the beauty!

Alex

OK, I agree with all of this. I don't even like regular airbags being mandated by the feds because of the extra weight, cost, difficulty of maintenance, and safety issues with children.

[alexbiker]

I have absolutely no problem with people killing themselves. However, it's good to put pressure on car manufacturers to make safety an issue.

Federal law may mandate seatbelt use, which I don't *think* it does, but US crash testing regs are focusing on unbelted passengers - one reason that makes airbags unsafe for children, since they are designed to absorb unstrapped adult energy levels.

This system has a lot of potential for problems, but it doesn't address some of the major issues that cause deaths. Here is the breakdown of fatal crashes across in Britain.

Percentage of deaths - car occupants: 49%

This system will not make a difference to other road users - the press release details cars only. So it will not affect 51% of deaths.

66% of drivers ignore speed limits. A 1% reduction in traffic speed causes a 7% reduction in fatalities.

15% of deaths involve a drunk driver.

Why bother with fancy brake systems?

1. Enforce the speed limits in urban areas properly - most people do 40mph in a 30 limit, raising the probability of a pedestrian dying from 45% to 85%.

2. Build in crash protection for pedestrians. This should be mandatory, as it is not a restriction of personal freedom, but a protection for other people.

3. Build continuing education and retesting for new drivers into the system - currently, I could pass my test, buy a 300bhp Sierra RS Cosworth for less than £2000, and drive it how I wanted on the same day. Limit this. There is no way a new driver should go from a driving school hack mule to a supercar.

Why waste time with expensive radar based systems like this?

Alex

[Greg Locock]

"A 1% reduction in traffic speed causes a 7% reduction in fatalities."

Round things

So if we reduce our speed by 7% we'd get a 50% reduction in fatalities?

If we reduce our speed by 14% we would eliminate traffic deaths completely?

As to your other point further up the thread, most accidents are caused by dumb drivers, not evil drivers, and waking them up when the laws of physics are about to reduce their options is a very good idea.

[KenC]

Originally posted by alexbiker
Here is the breakdown of fatal crashes across in Britain.

66% of drivers ignore speed limits. A 1% reduction in traffic speed causes a 7% reduction in fatalities.

Like Greg, this supposed statistic caught my eye. It seems like a decimal was misplaced somewhere. When I was a grad student we did a case study of speed limits and the death rate, using the US's NHTSA statistics, in predicting the effect of raising the speed limit on motorways. My recollection was that if one raised the speed limit 10mph, one could expect a 7mph rise in average speed, and roughly a 10% increase in motorway deaths. Using percentages, the 7mph increase in average speed travelled was about a 9% increase in average speed. Thus, the conclusion was a 1% increase in average speed, results in roughly a 1% increase in motorway fatalities, and vice versa, a 1% reduction in motorway speed results in about a 1% reduction in fatalities. I doubt motorway fatality statistics are an order of magnitude worse in the UK than in the US, in fact, I'm quite sure they're better, so I would hazard to guess that the above stat has a misplaced decimal.

[random]

Mercedes has a heuristic in some of their cars that accomplishes a fairly good level of anti-collision without any fancy vehicle detection mechanisms. It's just a bit of programming in the ECU.

It seems they analyzed drivers that were involved in rear-end pileups. It turns out a lot of drivers that ran into cars in front of them did so because they were too worried about the following car running into them. In trying to prevent the following driver from hitting them, these drivers let off the brakes and ran into the car in front of them.

The Mercedes system recognizes the signs of a driver in such a situation and fully applies the brakes in an attempt to prevent the accident. I believe the software looks for an emergency-stop level of braking, then a quick reduction in that braking. According to the auto magazine where I read about it, they couldn't get the system to false positive or cause any problems, even though it seems like it might. I suppose it's that requirement for an "emergency level" of braking which makes the system quite safe for everyday driving. As most people never use that level of braking unless they want to come to a full and complete stop. I think they said even driving the car on a race track with hard braking zones didn't set it off.

Which brings back one of the basics of driving, getting on the brakes will almost always save your ass a lot more than getting on the gas. The more momentum you lose, the safer and less harmful any impact will be. This system just effects that for those without the knowledge or skill.

[Greg Locock]

Is this in production? I wouldn't like to be in Court defending this system, having been in exactly the scenario described.

The quick witted driver realised we were about to become the strawberry jelly in a truck sandwich and came off the brakes, bounced off the front of the truck behind, and darted around the side of the truck in front.

Having full brakes applied at the same time would have killed the steering. The car was about 6 inches shorter after that one.

I /guess/ with ABS he might have still been able to make the manouevre under heavy braking, but my impression was that time was of the essence.

[Leo]

The system described by 'random' is widely used and called Brake Assistant (BA, part of the ESP-package) when purchased form Robert Bosch GmbH. Description on the website:

"Brake Assistant
The Brake Assistant is a system that supports the driver in "panic breaking", in other words in panic-reaction or full-breaking situations. This system can boost the breaking pressure above the level which would normally be applied in response to the pressure of the driver's foot on the brake pedal. The Brake Assistant is controlled by registering the driver's braking request (pressure in the master brake cylinder) and sending these measured values to the ECU. This means that if a critical situation arises, even an inexperienced driver can brake his or her vehivle to a standstill in the shortest possible distance."

[random]

Originally posted by Greg Locock
I /guess/ with ABS he might have still been able to make the manouevre under heavy braking, but my impression was that time was of the essence.

Yes, these systems are ABS so they don't kill the steering.

[AndreasNystrom]

actually, i think both Mercedes and BMW has this system on their cars.

Ive seen on Mercedes on the dashboard, a little meter that shows how far off the car infront of you are, and it automaticly starts to slow down, if you are coming near the car infront too fast.
but not any panicbraking, it does this early on, and keeps the distance to the car infront

[alexbiker]

Andreas,

in the Mercedes, this is the "distronic" system. It uses a radar detection system to measure the distance to the car in front and thereby adjust the speed setting of the cruise control system. It does not affect the brakes in any way. As with everything Mercedes, it is a system BMW uses, with "tronic" added to make it *special*.

Alex

[masterhit]

This is the sort of thing which the manufacturers claimed they would implement if traction control was made legal again in F1 cars. It was part of their argument.

Now that TC is legal, whatever happened to that idea?

It would sure make waiting for everyone to find their place on the grid faster!

[KenC]

Every time I see this thread heading I think, how does atom smashing at CERN relate to a technical topic on F1?

As for the actual system noted, I drive a Mercedes with their yaw control system, called ESP. And, like the Honda system described, part of the ESP system in addition to braking just one wheel to help pivot a car in under/oversteer conditions, is to cut the throttle. It's disconcerting to be in a 4-wheel drift, and have the car start to slow, as you jam on the accelerator!

For an experienced driver, having full control of the vehicle is preferential and these systems can be disabled. However, one has to note that these systems/aids are designed for the lowest common denominator, and in that case, I can understand the throttle kill, and emergency brake assist systems. The Mercedes also has a brake assist, where if you jam on the brakes, it will automatically boost the pressure to maximum.

[Garagiste]

Forget who said it now, but they were right - these secondary safety systems do nothing to prevent accidents. If you want to prevent accidents get rid of all the airbags, and put a great big sharp spike poking out of the steering wheel.
That way there's a chance that people might actually think about the consequences of their actions whilst they drive...