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I'd like to have a strong metal spike, fired into the road by an explosive cartridge, attached to a metal cable with a brake on the cable reel. It should be manually operated.
It would only be for emergencies such as when a car is sliding out of control towards a cliff with no hope of stopping.
It should be strong enough to hold the car after it goes off the cliff.
60 MPH is 88 ft/sec, so an 88 ft cable should allow for 3G deceleration (96 ft/sec/sec). I'd want the brake set for 6G in case of higher speeds or brick walls.
I realise it would damage roads, and I don't want the car in front of me to have one, but in a life or death situation it could help. Kind of like a parachute in a tall building - it might actually kill more people than it saves, but I'd like the chance to be in control.
Automotive aerobraking
http://www.halfbake...otive_20aerobraking Won't let you dangle from a cliff, but then who'd want to? [phoenix, Feb 05 2002, last modified Oct 17 2004]
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Annotation:
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"...I don't want the car in front of me to have one..." |
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Which, oddly enough, makes it sound like a 'me too'. |
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Check out my 'Automotive Aerobraking' idea. |
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I'm slightly wondering how well you could get this to stick in the ground or road surface. Looking at the damage a fast car crash can do to a car, an anchor is going to face horrendous forces as it impacts and catches. You seem to think you can spread the force over a few seconds, but if you want the anchor to do anything other than bump behind you, you're going to have to find a way to make it stick into the road surface. |
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And asphalt is only a few inches thick anyway. An anchor would likely not hold. |
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You want to make cars safer by putting more explosives in them? |
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The amount of explosive force necessary to drive the spink into the road would probably shoot the car up into the air and you'd be even worse off. |
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springiness (is that a word?) of the cable. |
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I beleive "elasticity" is the word you were searching for. anyhoo... why are you so caught on this idea that you need and emergency, emergency brake. if you have decent tires, no hydralic leaks, good brake pads and a properly adjusted ebrake then you shouldn't have any trouble stopping your car, even in the "fell asleep at the wheel while street racing on the cliff" scenario.
In addition, if you have enough of a reaction time to set this thing off then you probably have time to swerve away from the edge. |
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I saw one of these on the UK TV programme "Tomorrow's World", which used to show off shiny new tech. Anecdotally, this caused said tech to fail and disappear without a trace. |
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I think it must have been around 1990 I saw it, but possibly as a piece of archive footage they'd dragged out to show again: a Mini with an explosively powered bolt and a chain or cable attached to the back axle. |
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They took it for a test drive. Hit the brake hard, which triggers the bolt. It tore the back axle out and the rest of the car cheerfully carried on. Most amusing! |
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Quick search didn't show up anything linkable, sorry. |
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//It tore the back axle out and the rest of the car cheerfully carried on// More than likely - the Mini is front-wheel drive. Might stop a rear-wheel drive car quicker, but having seen American Graffiti, this may not be the case. |
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The problem is that you're trying to stop the whole car,
whereas it is really only essential to stop the driver, who is
much lighter. |
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What you need is to replace the conventional seatbelt
with a four-point harness. The harness is not connected
to the car (as would usually be the case), but rather to the
Spike-o-Matic device. Upon activation, the spike is
deployed, harpoonesquely, through the rear window, and
lodges in some fixed object. The driver is then extracted
from the car via the back window, with only minimal load
on the spike, tether and fixed object. |
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An additional plus, [MB], the flight through the back window
is likely to remove arms and legs thus reducing the load
further. I like it. |
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