On Sunday 07 March 2010 01:08:47 am Mikkel wrote:
On 03/06/2010 06:45 PM, Ed Greshko wrote:
> A car would work without a differential in much the same way a wagon or
> cart would. However, when cornering the tires would need to rotate at
> different speeds. This would tend to cause slipping on one side and
> dragging on the other and lead to control problems as well as damage to
> the tires.
A better fix would be to only drive one wheel. Having a way to lock
in the second wheel would be useful, but not necessary. My snow
blower is set up that way - a live axle, and only one wheel driving,
unless you manually engage the lock on the second wheel so they both
drive.
That might be convenient for a snow blower, but not for a regular car. Having
torque only on one wheel means that only one wheel is pushing the car forward.
This would lead to control problems and damage to the tires while driving
straight, as opposed to corners. In addition, it would make the whole car
quite unstable at high speeds and during braking, since the car's center of
gravity is not inline with the friction force between the tire and the ground
(ie. nonzero torque in the horizontal plane). This means that back of the car
would tend to move sideways compared to the front, while driving straight.
I wouldn't want to drive such a car on a highway. Even more importantly, I
wouldn't want *others* to drive such cars on the same highway as me. :-)
Not to mention things like accelerating/braking from/into a corner, driving on
slippery surfaces and such stuff.
Finally, an eventual locking mechanism would be quite complicated to construct
and implement. You would want to keep the lock on all the time except when
cornering. And while cornering, the car would behave differently in left
corners compared to right corners.
You can get a feeling of how such a car would behave if you appreciably deflate
one of the tires on a regular car. (Disclaimer: I am *not* advising you to try
that!!!)
A differential is a *way* more simple and elegant solution, which completely
avoids all these problems. ;-)
Best, :-)
Marko