Re: encoders

TADGUNINC@... wrote:

> From: TADGUNINC@...
>
> I know this has been covered in the past, unfortunately I'm in the process of
> trying to get Linux up on the comp. with most of my links, so if anyone can
> tell me.....
> I have a bunch of encoder disks with some kind of opti diode sensor, still
> trying to figure out the input output, with very poor resolution 40 slots per
> rev. if I offset phase them equally and stack five of them 200 spr and run
> them, 5 to one, reduction rate of stepper to ball screw, and put the output
> in quadrature would that be sufficient resolution?

I really don't think this is going to work. I don't know how you can stack them
without the sensor always seeing 'black'.

> if so how do i get
> quadrature output? I know what it is, but am unfamiliar with how to make the
> circuit.

There is no circuit! You have two sensors aligned so that one is exactly in the
center of a slot when the other is exactly at the edge of the slot (assuming the
slots are equal to the bars between them). Then, the two sensor signals are
fed into the encoder counter chip of whatever system you are using. The
alignment of the two sensors as above provides a 90 degree phase shift,
which is the trick to the quardature system.

Jon