What high precission distance sensor?


In the company I work for, we have an issue with one specific component of the machines that get bent over the time. We have got tens of thousands of them. This are quite expensive, but are not critical for safety, so at the moment we set them back to original spec manually.

I an due to start with my final course project, and I am thinking to do a machine to set them back to spec automatically. This machine will work in a similar way to a cnc wire bender. In this case, one sensor will check the ofset of the part, and one rotating head will bend it back to spec.

The point where the measure should take place is very specific (about 0.5mm^2) and the precision required is 0.02mm.

In order to speed up the process, physical contact of the sensor should be avoide, so I guess IR or ultrasonic should be used.

I have read many other post, and 0.02mm seems to be to much precission for the most of the systems available (other than a laser micrometer).

Please, any suggestion or idea on how to solve it is more than welcome.

Thank you in advance

I see nothing in your post that leads me to think an Arduino might be useful in your project. But, lest me ask a followup question.

If you were able to build something to detect and quantify the bending of your product, have you designed a machine capable of bending the thing back to within specifications.

Just being able to quantify something does not lend itself to correcting the problem.


I am no expert but start with this link: https://www.e2esoft.com/camm/
Using a video camera is definitely non contact and surprisingly accurate.
Good Luck & Have Fun!


Thank you both for your replies.

Your are right Paul_KD7HB. I forgot tu mention that the rotating head is moved by a stepper motor. The idea is: The sensor will check de distance to a given point of the component. It sends the data to the Arduino, and it then rotates the motor in order to bend the component. This process continues until the value for the sensors is the spected.

Gilshultz, that seems like a good idea, but I consider it out of my range at the minute. This is only my second project with Arduino and my background is Mechanical. I will consider it though.

Perhaps you are confusing sensors that measure LINEAR distances with sensors that measure rotation. Your description seems to conflate the measurements.


Hi Paul_KD7HB,

Thanks for your answer.

Both the component and the sensor will be fixed. The sensor will be pointing to the tip of the component. The sensor will get a reading, send it to the Arduino, and the arduino will move the rotating head to bend the tip of the component. Now the sensor will get another reading and if the reading is now the correct one, the process will finish, if not, the rotating head will work again based on this new reading. This process will continue until the reading is the correct one.

A simple mechanical stop might easily solve the problem.


Look up “time of flight” sensors.