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Unread 03-12-2012, 16:17
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Ether Ether is offline
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Re: Behind The Design 2012

Quote:
Originally Posted by jsmeldru View Post
We used a PID. The input was the rate of a light sensor (3 division flywheel was on the shaft of shooter). We had 3 preset shoot speeds based on different locations on the field: top of key, bottom of key, hail mary. We also manually modified those speeds during the match depending on ball "squishiness".
Thanks for the quick response Jay.

Couple of follow-up questions if I may:

1) Perhaps you've posted this somewhere already, and if so my apologies: could you share a bit more detail about your PID? e.g. did you use feedforward, or integrate the PID output, or tune I like P. How closely were you able to hold speed. stuff like that.

1) Adam mentioned you selected the 2.5:1 gear speed reduction because it was the fastest to reach 4000 rpm. Did you try using a bang-bang controller which is noted for reaching the setpoint very quickly.


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