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Unread 19-01-2009, 13:46
GeoffP GeoffP is offline
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Re: pic: steering methods

Quote:
Originally Posted by jgraber View Post
Very nice drawings, thank you.
Can you add one for wide drive, with independent linkages for front and back, or some other way to allow strafing right left?

I think left-right independent drive is enough, 4wheel not needed, although independent wheel motors are easier to angle.

Most posts on traction control mention limiting wheel slip, not checking for torque. What kind of sensor would you use to measure torque? Some kind of chain tension sensor?
you can play with the linkage positions to make the inside radius turning wheels turn more than the outside wheels (so neither have lateral slip during turning because the radii have the same center).
A simple way to make the independent drive wheel is use a castor, bolt the gb to the bottom/swivel of the caster along with a steering arm, then connect the wheel directly to the gb output shaft. then just attach the linkages or chains to the steering arm. 4 wheel steering is ideal and only requires one drive design X4.
I'm not familiar with traction methods but I would think you could monitor the current and see a sudden drop when the transition from static to dynamic is reached, the power to the motor could then bump down to 30% to re-establish traction and then brought to 90% as its new target.
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