What Type of encoder is This?

lardom

I let a quadrature encoder gear motor sit in a drawer for a year because I found a stepper easier to learn. I'm ready for it now but I'm asking someone to please help me understand what I'm looking at. I attached pictures. All I can tell is that there are two hall effect sensors.

ElectricAye

If those are Hall effect sensors, then I'm guessing you already know that the grey ring is probably a magnetic material with 4 or so separate magnetic poles in it?

lardom

ElectricAye, it might be more like a magnetic strip. I couldn't find any documentation. I was hoping it had a name. Without visible stripes or holes I have to find another way to figure it out.

Franklin

Seems like there are two pins marked A and B which are probably the output of the two hall effect devicse and are used like other encoder outputs (Google)

erco

You can get some magnetic viewing film to see the different magnetization patterns: http://www.wondermagnet.com/viewingfilm.html

ElectricAye

lardom wrote: »

...Without visible stripes or holes I have to find another way to figure it out.

If you're trying to figure out what the magnetic field looks like, perhaps consider using a magnetic visualization film, ~$3:

http://www.gaussboys.com/ndfeb-magnets/GVF075.html

I wouldn't try covering it with paper and sprinkling iron filings on it because there's a good chance you'd get iron filings all over the motor.

Perhaps if you give more info about what sort of wires it has, maybe somebody can tell you more about what its inputs and outputs probably are.

RonP

lardom

Out of curiosity I did some searching and found this http://www.hennkwell.com.tw/download/12.HE372E.pdf hope it can help. You might have seen it already.

Ron

RickB

Here is a BSEE project using this motor in a balancing robot.

http://eprints.usq.edu.au/6168/1/Miller_2008.pdf

The pdf states that the motor produces 12 pulses per motor rev and 624 pulses per output shaft rev.

Rick

lardom

I knew I could count on the forum for great information. I followed every link. I used "QuadDecoderDEMO" by Luke Haywas from the OBEX. The displayed variable didn't accumulate and I think it may be because I under-powered the encoder with 3.3V. I'll hack a mouse if I have to. I also have a set of encoder disks with stripes.

RickB

Do you recall where you got that motor?

lardom

I don't remember. I think I only paid about $12 for it but 160 RPM is a little slow. I bought it way before I had a decent amount of experience. I will learn how it works then buy a better one.

lardom

It works! :cool: I supplied the encoder 5V from the Prop and the variable accumulated. I guess my next step is to study boe bot code.