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Unread 25-02-2014, 10:21
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JamesCH95 JamesCH95 is offline
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Re: Automatic catcher?

Quote:
Originally Posted by EricS-Team180 View Post
We are currently using one LV-EZ4, looking up at a shallow angle, from the base of our catapult. It "works", but the threshold of where we want to trigger our grabber and hands is varying too much. ...say from an analog threshold of ~9 to ~30. The result is that we sometimes miss the auto-catch, and the operator has to recover manually. That doesn't sound like a big deal, but time is precious. For now, we've decided that the ultrasonic - mounted as we chose - is not as reliable as we want it to be. Unless we calibrate before each match, or understand the drift, we'll likely swap it out with an optical sensor at our first regional in Orlando.

@JamesCH95: have you seen your threshold move around like that?

@JoeRoss: you bet we used that voucher
Thanks,
Eric
In a word: no. We have them aimed near-vertical and they trigger very reliably as the ball drops into our catcher. It sounds like you have a geometry issue as much as anything else... from what you describe it seems like you're trying to bounce sound off of the ball nearly tangent to its surface.
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