Quote:
Originally Posted by squirrel
Thanks for the explanation, Fred. We now know that the maximum force that can be transmitted by a mecanum wheel in the forward direction is not as high as with a regular wheel. How does this affect the power transmission? Is there more frictional loss because of the side pointing vector? If so, how could I calculate that?
Also, what about the speed? If the rollers are not rotating relative to the wheel body as in straight ahead driving, is the full speed of the motor applied by the wheels?
The paper is interesting, but doesn't offer any explanation...it seems to be mostly selling the new design.....it would be nice if it had even a little bit of actual theory, and really nice if it had some empirical data to back up the claims.
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The friction comes into play of course, but that is a very hard number to get at short of actual experiments, and of course varies greatly with the type of mecanums being used.
Speed however will change. It is our experience that the rollers do in fact spin while going straight. On the ground the force is encouraging them to spin, and "perfect" traction would prevent that, but this is usually not the case. I suspect that there is some movement on the carpet, but additionally as soon as the wheel rotates the rollers will spin more as they pick up off the floor.
If at all possible, it would be a great test to get the same diameter wheels as the mecanum and compare speeds on the official carpet. We did not go into that much detail with our prototype analysis, but we made a rough estimate with vector calculations to adjust the gear ratios accordingly for our ideal fps.