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Unread 19-01-2007, 21:53
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Post Joystick Linearity

Here are the results of our test of two calibrated default joysticks. We used a ruler to see the changes in mm every 20 y values (using dashboard to see the values). We have concluded that they are linear.

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Last edited by NinJA999 : 19-01-2007 at 21:59. Reason: Link to site
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Unread 27-01-2007, 22:29
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Re: Joystick Linearity

They better be! They use linear potentiometers, after all.

That said, the linearity of the joystick can be misleading. If you do open-loop drive control (i.e. pwm01 = p1_y), you will find that the speed of the motor on pwm01 will NOT increase linearly over the entire range of the joystick.
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Unread 28-01-2007, 10:21
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Re: Joystick Linearity

Right. We have implemented code that makes the pwms linear, and it runs so much more smoothly now.
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Unread 28-01-2007, 15:41
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Re: Joystick Linearity

Quote:
Originally Posted by NinJA999 View Post
Right. We have implemented code that makes the pwms linear, and it runs so much more smoothly now.
We implemented a look up table to purposely make them nonlinear. We like more sensitivity around the center to make it easier to drive slow and precise. We lose sensitivity at full speed, but when you want to go fast sensitivity is not as important to us.
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Unread 28-01-2007, 18:49
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Re: Joystick Linearity

Interesting. To do that we implemented a reduced speed switch on the trigger.
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