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Volvo Introduces a Collision-Proof Car
carazoo.com sends along a story on Volvo's upcoming crash-proof car. The company will introduce a concept car based on the S60 this month at the Detroit Auto Show, looking ahead a few years to the goal that by 2020 "no one should be killed or injured in a Volvo car." The concept car will have forward-looking radar as a proximity sensor, and the ability to brake if a collision is imminent. When the car senses a collision, a light flashes on the windscreen display along with an audible warning. If the driver doesn't act, the car will brake automatically.
Much like in Sweden, the country Volvo is based in (I'm not saying you're wrong, I'm just saying I strongly doubt Volvo hasn't thought of that).
Actually, a General Products hull won't save you. Cars already are less strong than the could be, because their squishy contents are too susceptible to high acceleration. A perfectly rigid car body would just kill its passengers.
> Apparently, they don't have Anti-Lock Breaking in Canada
We do. It does not work with zero traction. Locks, releases, locks releases, locks releases ....
http://en.wikipedia.org/wiki/Anti-lock_braking_system
While ABS offers improved vehicle control in some circumstances, it can also present disadvantages including increased braking distance on slippery surfaces such as ice, packed snow, gravel, steel plates and bridges, or anything other than dry pavement.
I tell everyone I know (in wintery climates anyway) to buy a good set (4, NOT 2) of snow tires. They all tell me to get stuffed because they have new "all season" tires (all season in Alabama, maybe) or they have a 4WD SUV or whatever. 4WD only helps you get going, not stop, and antilock brakes are only as good as the tires and the surface the tires are on. I do use snow tires in winter, and trust me, there is a world of difference! The only accident I was at fault in was an ice storm that caught me by surprise the day before I had intended to put on the ol' blizzaks. I left work at late at 8PM hoping to be the only person on the road. Began stopping what seemed like a reasonable distance for conditions, ABS kicked in as soon as I put my foot on the brake pedal and I slid all the way (under 25 MPH) into the back of the only other car on the road. New "all season" tires.
With blizzaks, when ABS kicks in you actually stop. Been using them for eight years.
GET SNOW TIRES. (I'm sure everyone in Canada already knows that. Few people around here seem to know or care.)
More music, fewer hits
I do believe there's a single type of material that ABS helps reduce stopping distance but in all others the idea is to avoid the collision entirely, not just "stop faster". Thus, wheel lock = all traction gone, but "abs lock" = turn/swerve.
"An H2 commands plenty of respect on the road (and off the road)"
Over here in the UK you're more likely to get laughed at if you drive one of them round the streets and have people shout "tosser" at you.
Anybody who feels the need to drive an oversized military-style vehicle half a mile down (sub)urban roads to buy a pint of milk or a new pair of socks is looked on with a degree of suspicion and pity. People are a bit wary that the driver isn't too concerned about the well being of other road users and pedestrians.
In Sweden (and other parts of northern Europe) it is allowed to drive on spiked tyres in winter; and many people actually do this. It is quite helpful when driving e.g. on the winter roads: frozen lakes. Those roads are opened every winter and are indicated on normal road maps.
The answer is, it depends.
First point -- the ABS in a racecar is an entirely different ball of wax than what you get in a production car. It's designed for people that operate closer (and past) the limits of the tires adhesion as their day job and tuned appropriately. Discount comparisons to race ABS to street systems.
On bikes with ABS and race riders going over uneven grip surfaces (i.e. pavement with standing watterpuddles), the ABS bike cut the stopping distance in _half_. That's huge.
On dry tarmac with a good driver, most _production_ ABS systems will not allow the cars to slowdown at their maximum rate, which is where the tires have their absolute _maximum_ grip of ~15% slower than indicated road speed... i.e. straddling the threshhold between lockup and rolling. An ABS system typically intervenes prior to this point.
It is possible for me to be able to get my wheels to begin to hum/howl during threshhold braking and ABS will not activate.
Another area where ABS is a detriment is that it doesn't tend to actually work the way you say it does. Suppose I am driving on an uneven road -- right side dry, left side icy. If I hit the brakes, the left side will want to lock up while the right side will have grip. But maximally activating the right side brakes as you suggest will cause the car to yaw, as the right side will slow down while the left will not. For passenger car systems ABS this is highly undesirable as the driver must now provide an immediate steering input.
So in effect, most production car ABS systems will release brake pressure on the dry side as well to prevent the car from yawing. A talented driver could brake and counter steer to correct the yaw.
I agree that ABS systems have gotten much better, but on passenger cars, they do not outperform qualified humans in _all_ conditions. I have road course experience in production cars with and without ABS and the only thing production-car ABS is good for on a race track is saving you a little tire money (i.e. it keeps you from flatspotting a tire)
The best way to think about ABS is that it makes the default reaction of most panicing drivers an acceptable one. It is little more than a brake-force attenuator. If you hadn't pushed the pedal as hard at that moment in time, it wouldn't have done anything.
My street cars have ABS and I leave it on, because even though I have done many track days and have excellent car control and "looking ahead" skills, I can occasionally be surprised by something. Most humans (including race drivers) have the same reaction/reflex time.. the difference is in conditioned response and more so than that, prediction/anticipation. It is difficult to be in the zone 100% of the time when commuting or driving on the street, and so I don't expect my abilities to be at the level they are at when I am on the track. Accordingly, I like the money I've saved from ABS and stability-management systems keeping me from wadding up the car around town.
My opinions are my own, and do not necessarily represent those of my employer.
From one study ( http://www.nhtsa.dot.gov/cars/rules/regrev/evaluate/808206.html )
The principal findings and conclusions from the statistical analyses of accident data are the following:
* ABS significantly reduced the involvements of passenger cars in multivehicle crashes on wet roads. ABS reduced police-reported crash involvements by an estimated 14 percent, and fatal involvements by 24 percent. The finding is consistent with the outstanding performance of ABS in stopping tests on wet roads.
* Certain types of collision involvements on wet roads, such as striking another vehicle in the rear, or striking a stopped vehicle, were reduced by 40 percent or more. This benefit, however, was partially offset by an increased likelihood of being struck in the rear by another vehicle. The better your own braking capabilities, the more likely that a following vehicle with average braking capabilities will hit you.
* ABS had little effect on multivehicle crashes on dry roads. The contrast in the results for wet roads and dry roads is consistent with findings in stopping tests, where ABS improved stopping distances and directional control substantially on wet surfaces, but much less so on dry surfaces.
* The risk of fatal collisions with pedestrians and bicyclists was reduced by a statistically significant 27 percent in passenger cars with ABS. Unlike the effects for multivehicle crashes, this reduction was about equally large on wet and dry roads.
* All types of run-off-road crashes - rollovers, side impacts with fixed objects and frontal impacts with fixed objects - increased significantly with ABS. Nonfatal run-off-road crashes increased by an estimated 19 percent, and fatal crashes by 28 percent.
* Rollovers and side impacts with fixed objects - crashes that typically follow a complete loss of directional control - had the highest increases with ABS. Nonfatal crashes increased by 28 percent, and fatal crashes by 40 percent.
* Frontal impacts with fixed objects, where the driver is more likely to have retained at least some directional control prior to impact, increased by about 15-20 percent, both nonfatal and fatal.
* The negative effects of ABS on run-off-road crashes were about the same under wet and dry road conditions.
# The reason for these negative effects is unknown. One possibility is that average drivers may at times steer improperly in panic situations. Because ABS preserves steering control under hard braking, cars may be swerving or heading off the road.
# The observed effects of ABS on snowy or icy roads, while not statistically significant, were all similar to the effects on wet roads - i.e., positive for multivehicle collisions, negative for run-off-road crashes.
# The overall, net effect of ABS on police-reported crashes (including multivehicle, pedestrian and run-off-road crashes) was close to zero.
# The overall, net effect of ABS on fatal crashes was close to zero.
So the type of accident changes and the fatality rate seems close to the same.
Also this page shows various studies where decreasing one type of risk raises another also resulting in close to zero change. http://www.nationmaster.com/encyclopedia/Risk-homeostasis
https://en.wikipedia.org/wiki/Inverted_totalitarianism