Thread: pic: Omni Robot
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Unread 19-05-2008, 00:11
Nikhil Bajaj Nikhil Bajaj is offline
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Re: pic: Omni Robot

Quote:
Originally Posted by lukevanoort View Post
Depending on the motors used, using HB-25 speed controllers could be an expensive mistake, since HB-25s have about 37% less continuous current capacity than Victor 884s.
This mostly depends on the gear ratio they're using. With omnis, you have less traction due to friction in general due to the rubber used typically being more slick than traction wheels, so it'll be easier to spin out rather than stall on carpet. If the robot is geared for 25 feet per second you could run into problems with this (that number is an example, I don't know the exact threshold off-hand but you could use JVN's drivetrain calculator and the coefficients of friction off of AndyMark's site to estimate it. Or do what I do and forget every time so I draw the same free body diagram each time and solve the same equation.)

Since it is an omni-directional drive system, it should be relatively easy to get out of a situation where you are stalling motors.

That said, lukevanoort has a good point, when using the HB-25s using some 30A breakers is a very good idea to protect your investment. Remember the breakers for the Victors, too, I'd say.

By the way, how fast is this thing supposed to go?
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