Gear tooth sensor vs. Optical Encoders

[eugenebrooks]

Originally Posted by Avarik

I was wondering if anyone has tried using the gear tooth sensors from the KOP, and knows how well they work? I've used optical encoders before, and know those work well. So how does the gear tooth sensor compare, in terms of accuracy? If it matters, I'm planning on using one of these two sensors for robot speed and speed our launcher system is spinning.

Also, can the gear tooth sensors sense the direction of the spin, or just velocity?

And...while I'm at it...how does the accelerometer compare to these when trying to see robot velocity?

We used the kit gear tooth sensors last year, mounting them in recommended circuits on PC boards we laid out and etched. We had no problems with them. We never considered picking up the direction signal, but if you want to do this without concern for problems with the interrupt service latency you can build some custom electronics that looks at the pulse width and selects one of two outputs to send the pulse out on, one for forwards and one for backwards. A little electronics work, but do-able.