Gear Tooth Sensors

[Lord_Jeremy]

Are we allowed to use the Gear Tooth Sensors provided by FIRST two years ago on this year's robot? Rule R32 says we can't use FIRST custom made parts from previous years, but I don't know if the sensors are included in that.

[DonRotolo]

The question to ask is, can you buy the exact same thing somewhere? If yes, it is a COTS part. If not, it is not and can't be used. I believe the latter (= no) is true, but I ask others to also comment.

BTW, you can buy the sensor and build your own.

Don

[Lord_Jeremy]

Thanks for the speedy reply. As it were, we were hoping to get sensors soldered and ready for testing before friday, so ordering additional parts is an undesirable option. If anyone can recommend any Gear Tooth Sensor solutions, please speak up...

[SuperBK]

We used these last year. They run off of 5V instead of the 5 and 12 that the FIRST sensor boards needed. They are open collector so you have use a 4.7K pullup resistor on the output signal.
http://rocky.digikey.com/scripts/Pro...480&M=1GT101DC

Here's a thread with pictures on how they can be mounted:
http://www.chiefdelphi.com/forums/sh...ad.php?t=62083

[DonRotolo]

If you are using the toughbox from the KoP, or can somehow get a 1/4" shaft to turn with whatever you want to turn you can use the encoders supplied in the KoP this year.

You can use a photo-interrupter. There are two interrupters inside a ball-type (old style) mouse. Radio shack sells an LED / Photo-diode set that can be used. Just shine the light beam from the interrupter through something that interrupts the beam (like the teeth of a sprocket, a piece of chain from above, a special-built interrupter wheel, spokes of a KoP wheel, etc.)