Encoders with QRD1114

Hi Daniel,

I've used the QRD1114 for this, as detailed on my page:

Specifically:

"For anyone wondering about the wheel encoders, it turns out if you use a

6.8K pullup resistor on a QRD1114 sensor, it produces what amounts to a digital signal (about 0.15 volts for white, 4.95 volts for black)."

It seems to work quite well. My encoder wheels are somewhat more coarse than yours (the encoder band is about 13 mm wide), but I did it that way more to make the code simpler (I was sampling the 2 digital I/O lines on my PIC, which was also busy doing a lot of other stuff). If you had it hooked to an interrupt line (or you can poll a lot faster than I could), you should be okay.

Later, Jon

-------------------------------------------------------------- Jon Hylands snipped-for-privacy@huv.com

Project: Micro Seeker (Micro Autonomous Underwater Vehicle)

Slightly off-topic to this...

What was the reasoning behing using the pair of ultrasonic sensors? Was it to broaden the beam a little more? Given both are on the same pan mechanism, would that do anything that a slight shift in the horizontal axis wouldn't do?

Just curious.

-- Gordon

All of my mini-sumos have two range-finder sensors on the front, mounted side by side like this. It allows me to, in one time slice, see if the thing I am sensing is directly in front, or off to one side. Theoretically, you could figure out the same information with just one sensor, but it would take a lot longer.

The other thing two sensors gets you, if they are offset and angled correctly, is the ability to fake a pencil-beam sensor. Basically, you only pay attention to stuff that shows up in both sensors, and you know when it does that it has to be pretty much straight in front.

Later, Jon

-------------------------------------------------------------- Jon Hylands snipped-for-privacy@huv.com

Project: Micro Seeker (Micro Autonomous Underwater Vehicle)

Aha! This makes a lot of sense. Thanks for the details.

-- Gordon