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Unread 01-02-2010, 20:51
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Ether Ether is offline
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Re: Holonomic issues

Quote:
Originally Posted by dwodrich View Post
I have validated that the wheels are mounted correctly "x" from the top "o" from the bottom.

I have validated that we are sending in the correct vector in degrees. 0 for straight ahead.

We can move forward with 0 and backward with 180 when motors on one side are inverted. But we have no ability to strafe. The motors are each side are fighting each other.

When we change the motors so that none are inverted. We can strafe side to side with no issues, but we can no longer go forward or backwards.

Check polarity on all the jags.

Anyone have any ideas? seems like we are making a simple mistake.

TOP VIEW of robot:

front
1......2
.........
.........
3......4
rear

numbers in chart above refer to the wheels.
wheel#1 is front left
wheel#2 is front right
wheel#3 is rear left
wheel#4 is rear right


Put the 'bot up on blocks and test it with all six commands (fwd/rev, slide left/right, spin clockwise/counterclockwise) and tell us which direction each of the four wheels is being driven for the different commands.

Here's what you should get:

forward command: all 4 wheels spinnning forward

reverse command: all 4 wheels spinning reverse

slide right command: wheels 1 & 4 spinning forward; wheels 2 & 3 spinning backward

slide left command: exact opposite of slide right

spin right: wheels 1 & 3 spinning forward; wheels 2 & 4 spinning backwards

spin left: exact opposite of spin right

download this PDF file and carefully study the chart at the bottom left of the page:

http://lib.store.yahoo.net/lib/yhst-...lSpecSheet.pdf


~

Last edited by Ether : 01-02-2010 at 22:41.
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