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JimBob666
04-02-2010, 19:26
Does anyone have Mechum Wheels working in LabVIEW. If so could you send us the VI doc. because we are in a dire need of help. This does not speculate any weaknesses on our bot, but we still need the VI. We are trying to use Holomonic Drive VI but it does not have joystick inputs and we do not know how to fix it. Thank you and we would really much appreciate if anyone could give us helpful information. GOOD LUCK everyone in the upcoming competitions! ::safety::

Pausert
05-02-2010, 15:05
What you need to do is look at the Help File for the Holonomic Drive VI. You simply need to convert your joystick output into a magnitude, direction, and a control for "rotate". This can be done with various trig functions.

Tom Line
05-02-2010, 17:19
Actually, by feeding your joysticks directly into the rect/complex to polar vi located on the "complex" sub-pallette under the mathematics pallet, you will obtain both the angle (in radians, and oriented in the polar manner, that is to say that zero it to the right) and the magnitude with no trig on your part at all.

bladetech932
05-02-2010, 23:49
make sure when you wire the magnitude into the holonomic drive vi you put a case in if > than 100 than it equals 100

Greg McKaskle
06-02-2010, 08:00
Just an equivalent tip, but the Comparison palette in LV contains an In Range and Coerce node that is quite useful for this sort of thing. In your case you want to use the coerced value and may not care about the In Range portion.

Greg McKaksle

Hadi379
07-02-2010, 17:19
We've been having trouble converting our directional outputs for the holonomic drive. Attached is what we are currently getting and what we think we need. Is this correct? And if so, can someone please help us program this properly. I feel like everything needs to be rotated 90 degrees counter clockwise, but have no clue as to how....

Tom Line
07-02-2010, 17:30
Are you sure that picture is what you really have? Using the rect->polar conversion results in 0 -> 360 degrees, starting with zero on the right and increasing in the counter clockwise direction.

Regarding the 90 degree shift, yes, you're thinking correctly. Now you just have to figure how to normalize it (add or subtract 90 degrees) and how to bring it back to +/- 180 (hint - use the division with remainder function)