Hi. I'm looking for some advice on an idea to help with a process at work.
We make wiring harnesses/looms for industrial engines. wires have idents printed along them then are cut to length and usually they need to be twisted together. wire lengths can vary form under 1M to around 5M, sometimes longer
We have a twisting machine that has a counter where you can set the number of revolutions before it will stop.
The process for twisting is to measure the length of wire, look up how many revolutions are needed for that length and number of wires to be twisted on a chart and enter that on the counter. clamp the wires into the machine to the left and the other end into a similar fixed clamp on a moveable mount to the right to keep the tension. when the guard is closed over the rotating clamp it will start the twisting.
This takes time and people take short-cuts, putting in a high number and stopping when it looks right. which causes quality problems with wires being too slack or too tight.
I have been thinking of a way to improve this, I could interface an Arduino to the counter and have some way to measure the distance of someone holding the other side of the wires and calculate how many revolutions are needed. I just need a reliable way to measure distance. what would be the best way to do this?
My first thought was to use a rotary encoder, like a mouse wheel connected to something that could be pulled the distance needed, like those retractable cords for keys but be able to reach at least 5M. then looking on here I saw some topics on sonar range finding. how accurate are those? i guess it doesn't need to be exact, within a few cm will do. how good would it be at detecting a persons distance or would would the sonar be absorbed by their clothes? is there any other way of measuring distance?