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Unread 12-01-2015, 14:29
Foster Foster is offline
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Re: Talon SRX Encoder Breakout

Quote:
Originally Posted by adciv View Post
From a controls standpoint, I wouldn't recommend this for most cases. There will be an increased time delay between getting the encoder value from the Talon to the RIO and sending back the new control command. If you're going to use processing on the RIO, it's better to have the encoder wired to the RIO and use PWM. This is all to maintain the minimum possible time lag in the system.
Can I get some more details about this?

From what I read the values come back every 20ms. You get new values 50 times a second (20*50=1000ms=1 second)

The update rate is at 10ms, so you can update it 100 times a second, You are using slightly stale data.

At 10 fps (random robot speed that seemed reasonable) you will travel ~2.5 inches per 20ms period.

But you are not going to stop on a dime ( or turn on one) since your 120lb robot moving 10 fps has a lot of momentum.

Are the drive trains / actuators that sensitive to need higher update rates?

Or is this just a case of faster is always better?
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