I want to measure the number of meters of running cloth off of a fabric roll. So that when I press a button a motor spins a roll of cloth and the fabric is rolled onto a separate roll. I want to be able to measure the number of meters of fabric that runs from one roll to the other. What kind of sensor would I need to measure the length of running cloth?
I was thinking maybe remove the laser sensor from a mouse and use it to look at the fabric. What other possibilities are there for this problem? This is to be used on a cloth inspection frame, so a fabric quality inspector will press a button, the motor will start running the fabric; if he sees a flaw in the running fabric, he presses the button to stop the fabric, a sensor detects at how many meters the roll stopped, and the inspector enters a code for a type of flaw and presses the button again to start moving the fabric again. This way, quality data is recorded for a roll of fabric in a database.
Eventually one could pull up the quality inspection data and know exactly at what meter in the roll a flaw exists.