Half a croissant, on a plate, with a sign in front of it saying '50c'
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The phrase 'crumpled heap' comes to mind.

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Bum Steer

Lean to steer car, just like a bike
  [vote for,

Going through my favourite corner in a (diesel) car, I was sorely disappointed. The speedometer says I am going at more than my regular speed (on the bike) but the sensations are disagreeable. I’m stuck upright, there is no wind on my face and no asphalt streaming close by my kneecap. Spinning that wheel to make that behemoth turn is just plain slow and no fun at all.

So, I propose to build a car which is steered somewhat like a bike. To the uninitiated, the handlebars are the steering gear on a bike. Wrong. They are there to hang on to as you twist the throttle and the bike surges forward. On that car, floor the throttle and look in the mirror and watch the others drop behind – to avoid the belching black smoke. A bike is steered by leaning. The command to lean is conveyed to the bike by the seat of your pants.

You will be strapped securely to that seat (required by law, anyway) and sensors monitoring your body attitude will control the steering gear. Drive by wire. If it is good for airplanes, it ought to be good for cars too.

The conventional steering wheel will be retained for use at low speeds, for example for parking.

neelandan, Nov 09 2002

for yamahito http://www.animalfirm.com/steer.jpg
[thumbwax, Oct 17 2004]

(?) The Vanderbrink Carver http://www.carver.nl/home.htm
A car steered like a motorcycle [hollajam, Oct 17 2004]

Steering and turning a bicycle http://www.explorat...ycling/brakes3.html
confirms bris' comments [FarmerJohn, Oct 17 2004]

Counter-steering http://www.msgroup.org/TIP048.html
[phoenix, Oct 17 2004]

Counter-steering - part deux http://www.virginia...m/tips/steering.asp
[phoenix, Oct 17 2004]

(?) Carving Down the Road (.PDF) http://www.daimlerc.../elektronik_5_e.pdf
DaimlerChrysler's F200 and F400. Cars that lean into turns. [phoenix, Oct 17 2004]

Bike with a car sidecar http://www.itechdia...-motor-and-car.html
[goldbb, Sep 28 2009]


       nothing to do with cattle, then?
yamahito, Nov 09 2002

       Thumb's got it ;op - great link.
yamahito, Nov 09 2002

       Actually the bars do turn the bike. By placing pressure against the bar you move the front wheel. The gyroscopic action of the wheel exerts a force 90 degrees to the motion causing the bike to lean. This is why push-pull steering works. Yes leaning will cause a bike to turn, eventually, but its the wheels that make it happen at will. The actual theory on how a bike actually corners is still under debate. Do a search on the net, its a pretty interesting read.
TBK, Nov 10 2002

       I've noticed that on a bike you actually turn the handlebars in the opposite direction to start a turn, at least at speed. Weird.
bristolz, Nov 10 2002

       neelandan, I think this is for you. The particular car I was searching for had a two wheel chassis. Couldn't find it but I think this three wheeled chassis is closer to the car steered like a bike that you are describing.
hollajam, Nov 10 2002

       It will barely haul half an average family. Not even room for baby's 'half' brother...
hollajam, Nov 10 2002

       maybe it is in hy head, but I'm certain my truck corners better when I lean in a bit. On a motorcycle you don't so much lean as just stay upright in relation to the bike, not the road.
rbl, Nov 10 2002

       bris: Um, you riding your bike the right way round? (Or are you also actually talking about a motorbike?)
DrCurry, Nov 10 2002

       <lucidity alert meter running>
po, Nov 10 2002

       Doc, yes I was, in fact. The next time you're riding one, observe closely what pressures you're putting on the handlebars as you initiate a turn, but not a low speed turn. I doubt it matters whether motorcycle or bicycle.
bristolz, Nov 10 2002

       Bri is right. Depending on the size and weight of your tires, "counter steering" kicks in at around 30 kph. Anything below that and the steering is the right way round. Turn right, go right, above 30 turn right, go left. Many people never realize this on a bike, in an emergency they panic and go the wrong way.
TBK, Nov 10 2002

       Of course it makes no sense, [waugsqueke]. It's counter-intuitive. But none the less it is true. It's an effect of the angular momentum of the front wheel.   

       Whenever you turn a spinning object around an axis perpendicular to its axis of spin, you experience a torque around a third axis that is perpendicular to the plane containing the other two. The torque is proportional to the rate of spin. In the case of a bike rolling forward, twisting the front wheel to the right causes a torque on the body of the bike that makes it lean to the left.   

       At low speeds, the rider's weight leaning into the turn creates a torque which is stronger than the torque caused by turning the wheel. Hence the bike actually leans with the rider into the turn and the turn progresses normally.   

       At high speeds, the torque created by turning the wheel is stronger, so the bike leans away from the turn. An experienced rider will expect this and steer the wheel briefly away from the turn to cause the bike to lean into the turn. Once the bike is leaning enough to stick the intended turn, the rider will then steer into the turn. The rider's weight leaning is now stronger (because he's leaning further over when the bike is leaning too) and it overcomes the torque caused by steering into the turn.   

       An inexperienced rider will attemt to steer the same way at high speeds as at low speeds. On a sudden sharp turn (like in a panic), the bike will throw itself over toward the outside of the intended turn and dump the rider headlong onto the road. Not a pretty situation, especially if you factor in the obstacle that the rider was trying to avoid when the panic turn was attempted.
BigBrother, Nov 11 2002

       Clench bum cheeks for horn?   

       I want a car I can steer with my pectorals.
venomx, Jul 09 2003


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