How to measure a vehicle with a high accuracy with mm?

[absoltue_beginner]

@cedarlakeinstruments

Let me get this straight: you are building something that moves on rails. You have absolutely no idea how to measure its position to within a millimeter, even though that's been a solved problem for decades, but you somehow managed to convince someone to give you money to build this thing?

ehmmm, yes. I am a beginner. But: I am an absolute talented beginner. I have never heard of Arduino or MicroController, never! And I had never a clue of electronics. Sicne 2 years, I came in touch with Arduino, and I thought: WOW

Yes, I even have a product on the market which works absolute well. It has been controlled by real educated electricians. They had no worries about my first product. And to be clear: I am absolute sure in what I am doing. And I am absolute convinced that I could build a 3D House-Printer. No doubt to that. Of course there are little problems like this topic here... but I can run Steppers, GPS, 433 MHZ ,, in other words: I learnded somethink

Okay, and my inestor who has much money, is... let me say... a man who even don't know how a human is build, but he has much money And, he absolutely trusts in me.