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Unread 03-03-2013, 21:44
Ian Curtis Ian Curtis is offline
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Re: Real-Time Scoring Not Working?

Quote:
Originally Posted by Greg McKaskle View Post
This seems a little vague. Can you give more details? What internet sensor were you using, what circuit was the sensor in, what was the resolution and rate of the measurement?

Greg McKaskle
Probably because it is a little vague, and perhaps a little premature. I believe was a custom Arduino rig, but I am fuzzy on the details. Basically we took raw voltmeter readings -- clearly you could do a lot post processing to smooth it out. I've attached one of the resulting data files -- as I recall our issue was not with a given run giving weird data, it is that you just couldn't get the same thing twice back to back. Clearly we were sampling way faster than the sensor was updating. We were using it as a thrust test stand, which is not a great environment for a load cell because there is a bunch of vibration. However, we had similar issues even using bricks. Using an electronic postal scale to measure the force at the same location on the lever, these issues went away.

I don't think I have any of the documentation on my computer anymore, but I'll email around and see if someone else has the part number.

EDIT: FC-22, the 0-10 lb version. I can't find somewhere where FIRST lists the sensor that they used, but this family of sensors pops up quite a big when I google around for low cost load cells. Anyone "in the know" or take a look at the field to confirm?
Attached Files
File Type: xlsx 11.10.2011_22-40-43_STAND_DRAG_TEST1.xlsx (22.9 KB, 2 views)
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Last edited by Ian Curtis : 03-03-2013 at 23:33.
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