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Unread 31-03-2016, 18:15
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Re: HELP; moving omni robot to move sideways

Quote:
Originally Posted by CalTran View Post
Wouldn't this be functionally the same as Killough, just a different geometry for the wheelbase?
Yes, as I noted, the two advantages were that no non-square cuts were required, and that the contact patches of the wheels with the carpet are farther apart for a given chassis size. Unless you designate the front of the robot as one of the corners, you would have to rotate the inverse kinematics 45 degrees. In principle it would be simpler. Designating the wheels:

1 2
3 4

As pictured, an assuming that a positive input to each motor causes a clockwise torque to the robot chassis, and assuming a "strafe plus rotation" joystick setup, the linear inverse kinematics would be:

Wheel 1: R + X
Wheel 2: R - Y
Wheel 3: R + Y
Wheel 4: R - X

Edit2: Also, it would have more usable interior space for controls and other mechanisms.
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Last edited by GeeTwo : 31-03-2016 at 18:19. Reason: swapped wheels 3 and 4 kinematics on first try