Precision laser distance measuring involves a beam splitter a modulator and a detector in addition to the laser source. You use the reflected signal as a "resonator" in an oscillator. The period of the oscillator compared to a very accurate source gives you a distance. At < 200 mm sort of distances this gets a bit complex. The delays in the electronics begin to creep into the equation. That's the first layer to the onion.
The next layer on the onion is that you need a good target. A polished front surface mirror is fine. A piece of glass with multiple boundaries - not so much.
Next layer is - ok, I have this pile of data, how do I correct of all of it? Off to firmware land or to Python land.
Next layer - I've got a pile of data, does it relate to the printer as it is now? I've run into that one with the auto bed leveling as it exists today. The issue in my case was temperature sensitivity of the servos. The problem I was trying to fix is a temperature dependance of the plywood parts at the "couple mm over 100 mm" level.
Final layer - who knows?
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None of that says that you can't do it. All I'm saying is that it's a pretty complicated problem.
The next layer on the onion is that you need a good target. A polished front surface mirror is fine. A piece of glass with multiple boundaries - not so much.
Next layer is - ok, I have this pile of data, how do I correct of all of it? Off to firmware land or to Python land.
Next layer - I've got a pile of data, does it relate to the printer as it is now? I've run into that one with the auto bed leveling as it exists today. The issue in my case was temperature sensitivity of the servos. The problem I was trying to fix is a temperature dependance of the plywood parts at the "couple mm over 100 mm" level.
Final layer - who knows?
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None of that says that you can't do it. All I'm saying is that it's a pretty complicated problem.