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Unread 17-02-2010, 10:02
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Ether Ether is offline
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joystick sensitivity adjustment

Here's a simple algorithm to add sensitivity adjustment to your joystick:

x' = ax^3 + (1-a)x

x is a joystick output ranging from -1 to +1

x' is the sensitivity-adjusted output (also will be -1 to +1)

"a" is a variable ranging from 0 to +1

When a=0, you get x' = x

When a=1, you get x' = x^3 which gives very fine control of small outputs

When a is between 0 and 1, you get something in between. See the GIF file screenshot.

So by adjusting a, you can find the right sensitivity for your driver.

You can find the right value of "a" by trying different values, and then hard-code it, or

If you have a joystick with a "throttle" control (like we do), you can use the throttle control to set the value of "a" (so the driver can adjust it whenever he wants).

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