RE: [CAD_CAM_EDM_DRO] Optical CNC

Jim,

I haven't noticed a reply to your mouse question so here goes.

Using a mouse as the encoder for position feedback has a problem in that
the update rate is too slow. The fps figure you give for an optical
mouse is misleading as it is not the rate at which the encoding chip can
provide position updates out the serial line. To prove that it loses
track of the encoder counts all you have to do is position your cursor
to one side of the screen and note the position of the physical mouse.
Not rapidly move it to the other side of the screen (not so far your
cursor goes off screen) and then slowly move it back to put your cursor
where you began. You will most likely not end up at the starting
position as you will have lost counts on the fast move. So you can see
that using the mechanism as is will not work.

Now you can use the encoder out of a mechanical mouse as it is just a
low res quadrature encoder. There has been discussion on using the
optical sensor on the newer mice, but the problem that came up is the
driver circuits drop into a low res mode when they sit still and you are
likely to drop counts when it first moves as it jacks up the power to
the led and the resolution.

Tim
[Denver, CO]

> -----Original Message-----
> Has
> anyone gave some thought to using an optical sensor from a mouse as
> guidance for the router? I see some mice (mouses) have up to 6000
> frames per second and even wireless. Most computers already use the
> mouse as an input, but could it be used with a router?
>
> Standing by,
>
> Jim