Re: Optical mouse for DRO anyone? - not for WIRE!

Well you can be sure that the surface texture of a cord will vary
quite a lot over the areas the mouse looks at so I still think that
the mouse will not work for long lengths.

I am not sure how fast you wish to measure the lengths but here is a
solution that might work and could be pretty fast anyway:

what about a two gripper system with one gripper on a pneumatic or
electric actuator, one pulls the cord out by a fixed distance the
other gripper holds it while the first returns to the start position.
With suitable grippers and correct design it would not damage the
cord and would be accurate.

Graham