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Unread 20-03-2010, 12:57
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Re: tank drive mecanum algorithm

Quote:
Originally Posted by Travis Hoffman View Post
Cut away all the code in between the driver's hands and the robot, go pure "motor = joystick", and some people can extract even more performance out of a robot.
I assume what you mean by "pure motor=joystick" is that each joystick degree of freedom (axis) controls one and only one motor.

For a tank-drive non-mecanum robot with only 2 drive motors (one for the left wheels and 1 for the right wheels), this certainly makes sense.

But for a robot with 4 mecanum wheels (and 1 motor per wheel), "pure motor=joystick" would require 4 joystick inputs.

I seriously doubt if any driver has developed the mental agility to individually and directly control each wheel command for a mecanum-wheeled robot.

That is why I presented the mapping of the 2 standard tank-drive joystick commands, plus 1 additional joystick command for strafe, to the 4 mecanum wheels via 3 intermediate variables which separate out the 3 robot degrees of freedom (fwd/rev, strafe, turn), so they can be tuned independently.

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