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Unread 09-01-2008, 12:10
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Re: Holonomic vs Mecanum Help!!

both systems are the same except that mecanum can goes faster forward and backward than omni (assuming everything else is the same). Mecanum can also make the chassis simpler, depending on the materials/methods you use.
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Unread 09-01-2008, 16:19
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Re: Holonomic vs Mecanum Help!!

The same exact code can be used with either configuration.

Generally, 341 has used conventional omniwheels for holonomic drives, since the available wheels are of much higher quality (in my opinion) than off the shelf mecanum wheels. If you can make your own high-quality mecanum wheels, you can get away with a more normal looking frame.
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Unread 22-03-2008, 23:29
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Re: Holonomic vs Mecanum Help!!

I think it would be a little simpler to program mechanum reliably as apposed to omni, as with mechanum, you can have a regular tank drive operator interface with one of the controllers also controlling side-to-side motion on the x-axis of the joystick. This is fairly simple code, the hardest part is just telling the processor how to move the front wheels back and forth opposite the back wheels, but that's pretty easy. With omni holonomic/Kiwi/Killough the robot pretty much has to be programmed to know what's forward. From what I've seen in VEX, Mindstorms, and FRC, mechanum tends to lend itself to a slightly more powerful drive train, as omni holonomic has almost no resistance to movement, basically making it a hockey puck on wheels (note the incessant fishtailing of 2158's robot from 2007 FRC, where we only had 2 omniwheels, and were pushed around easily).
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Unread 22-03-2008, 23:51
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Re: Holonomic vs Mecanum Help!!

Note: When I refer to omni, I mean a robot which has 90 degree omniwheels, one on each side of a square (or rectangle). That square can be rotated from the robot frame, meaning you have a wheel diagonally in each corner.

Quote:
Originally Posted by daltore View Post
I think it would be a little simpler to program mechanum reliably as apposed to omni
Unless I'm misunderstanding you, not really. As said before:
Quote:
Originally Posted by Abwehr
The same exact code can be used with either configuration.
Quote:
Originally Posted by daltore View Post
From what I've seen in VEX, Mindstorms, and FRC, mechanum tends to lend itself to a slightly more powerful drive train, as omni holonomic has almost no resistance to movement, basically making it a hockey puck on wheels (note the incessant fishtailing of 2158's robot from 2007 FRC, where we only had 2 omniwheels, and were pushed around easily).
Power-wise, mecanum and 4-wheel omni are exactly the same. You get ~71% (sqrt(2)) power in one set of directions, and 50% in the directions 45 degrees from the first. Any differences are in the construction of the wheels.
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Unread 25-03-2008, 16:57
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Re: Holonomic vs Mecanum Help!!

you should go with the 1565 Linkage drive system (that's IMHO of course ) thats the best bet lol! (look it up!!)
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