Holonomic Drive VI

[thomas.willson]

I can't figure out how to turn an x and y input from a joystick into direction and magnitude vectors for the Holonomic Drive VI. Help would be greatly appreciated.

[Burban]

Thomas,

If you take a look at the Joystick Input Example (located in the C:\Program Files\National Instruments\LabVIEW 8.5\examples\FRC\Robot and Motor\Joystick directory), you can see that the joystick axis 1 (x) and axis 2 (y) values vary from -1 to 1.  You can think of the maximum range of motion of the joystick as a unit circle.  As you stated, the Holonomic Drive VI requires a magnitude and direction.  For magnitude, you can use trigonometry to calculate the magnitude of the vector from the distance along the X axis and along the Y axis - use the Pythagorean theorem.  The direction, measured in degrees from the robots original heading, can also be calculated using trig.