Hopefully this is the correct area for this question. I've got a mini mill and am in the process of converting it over to a CNC. anyway i was thinking that with some of the new logitech mice out there that have a very high resolution i might be able to use for a measurement device to relay a digital readout on the PC. has anyone seen a mouse used in this way before, i have not. thanks for any input anyone may have.
http://home.comcast.net/~maccody/robotics/croms-1/croms-1.html That link shows just using the optical sensor rather than the whole mouse. I am not sure how you would stop the mouse enumerating as a mouse and thus stop iit from moving the mouse on the screen....
that is what i'm looking for, but you have a really good point on how to access the mouse and have movement without having the mouse actually move.
The other option is to use a digital caliper, most of these have digital outputs which are afaik are a fairly simple serial protocol which you can use to determine the location. This is what I am thinking of One advantage is that they will also have a digital display so you can visually check the value. I expect that the price will not be much different, or even less, than those mice. You would need one for each direction rather than just one for both. I really like that the calipers are absolute rather than incremental so they will not suffer from drift. Rod
That's a really good idea Rod10k. It'll be interesting to see how this turns out, keep us posted with what you did.
thanks for the link, that does look like a much easier solution in the long run and i probably will go that way. the one reason i was looking into the mice, was to be different plus it looks like the optics on some mice can be very accurate so if i could find a way overcome the problems that would come from using them it might be a fun project at some point. thanks again for the input guys and i'll let you know with pics when i get the DRO done.
The usual way this is done is by using stepper motors and lead screws. As you know the pitch of the screw and you can control exactly how many turns the motor makes you therefore know where the head is. Its probably the easyest way.
Lynx: i already have that part done. I'm using sanyo denki servo's, gecko drives controlled by mach3. that was the easy part. what you get with ballscrews and is nearly 100% impossible to get rid of is backlash. the dro from mach3 is ok, but i was looking for something a little more unique this is why i thought optics on a high end mouse might work out well. I hope this clears things up a bit on my end.
So you are going to use the mouse for fine adjustment? I would personally work out how big the backlash is and adjust my positons accordingly as I assume the backlash is pretty much constant. On the calipers they get out of 0 very easily and would be less accurate than any decent lead screws. Have you got special low backlash stuff or is it just normal gear?
for the screw it is a good accuracy rockford ballscrew and nut. i have the backlash down to .0002 on travel so that really isn't the problem. I think you may have gotten the incorrect idea on why i wanted to do this actually. more for a can i do it a different way with optical mice than the norm. also i agree 110% on the calipers getting out of whack, and i do not want to spend big money on interfacing mitutoyo's stuff. thanks for the info guys and hopefully i can figure some stuff out with the mice.
