Half a croissant, on a plate, with a sign in front of it saying '50c'
h a l f b a k e r y
actual product may differ from illustration

idea: add, search, annotate, link, view, overview, recent, by name, best, random

meta: news, help, about, links, report a problem

account: browse anonymously, or get an account and write.

user:
pass:
register,


                       

Rocket emergency brake

A 'retro rocket' controlled by the motion and direction of the vehicle
  (+5, -6)
(+5, -6)
  [vote for,
against]

This is a variation on previously tried ideas. When an emergency stop is required, a castoring wheel is lowered so as to contact the road surface. The castoring wheel 'steers' the rocket so that it always thrusts against the direction of travel. The rocket itself is made up of a multitude of 'slices' of solid fuel, divided by insulators which prevent each slice from igniting the next. When the first slice has burnt (perhaps 0.5 seconds) it enables the next to be ignited. Ignition of each slice is initiated by rotation of the castoring wheel, so that when the vehicle stops, no more braking thrust is generated. The downside to any emergency braking device is, of course, the vehicle behind. It's no good stopping your Smart car in 10ft from 70mph if the 40 ton artic behind can't do the same! The advantages of this system are: 1) It can be a self-contained unit which could be mounted to any vehicle, only the rocket thrust would have to be matched to the vehicle's mass. 2) It operates independently of the vehicle's stability, grip and directional control. 3) It stops operating when the vehicle comes to rest.
Twizz, Apr 19 2006

[link]






       Do not use at pedestrian crossings.
egbert, Apr 19 2006
  

       Echo.
//only the rocket thrust would have to be matched to the vehicle's mass// So no carrying extra passengers. [-]
coprocephalous, Apr 19 2006
  

       //(perhaps 0.5 seconds)// A series of explosions stoping your car, a bumpy ride.-
zeno, Apr 20 2006
  

       Most modern family cars weigh around the 2 ton mark. The addition of four 200lb passengers is only a 20% increase, so no problems with the extra passengers. A bumpy ride is better than a crash!
Twizz, Apr 20 2006
  

       Two tonnes is pretty close to the gross vehicle weight for my family car [checks Opel website] - correction - actually, it *is* the gross vehicle weight (-5kg), so four 100kg occupants would represent a 30% variation over the kerbweight. In a smaller family car, the percentage variation would be much greater.
So, the braking effort would vary over a range of 7.5 (driver only) to 30% (driver plus three passengers). Pretty broad range to cope with, huh?
coprocephalous, Apr 20 2006
  

       sp. "castering", unless its different in Britain.
sninctown, Apr 20 2006
  

       sp: it's (as in, "it is")   

       "Its" is the possessive.
Texticle, Apr 20 2006
  

       For my mountain bike, please. Then, I can collect scars on all sides of my body instead of the traditional places.
normzone, Apr 20 2006
  

       Elegant yet dangerous. Croissant. I do wonder what happens on the final rocket burn after the car has stopped though. If the rocket spins around in all directions that would be cool.
caspian, Apr 21 2006
  

       normzone - just make sure you do not cycle in this car's path - you would get roasted in 0.5s bursts.
wongmeister, Apr 21 2006
  

       If the rocket continued to burn after the vehicle had stopped, it would still turn to face the direction of travel. This would result in the rocket spinning as Caspian suggests. In vehicle dynamics in the UK, castor is the action of a wheel which trails its steer axis. Caster is finely ground sugar.
Twizz, Apr 21 2006
  
      
[annotate]
  


 

back: main index

business  computer  culture  fashion  food  halfbakery  home  other  product  public  science  sport  vehicle