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by rambojazz 1818 days ago
I'm not familiar with the 3d scanning tech, but my first thought when looking at the examples is that they do not look really detailed. What is the max "resolution" of the machine? Can it scan objects with a higher number of particles?
2 comments
dvoros 1817 days ago
Yes, you're right, this is extremely low resolution, compared to commercial scanners. This is mostly the result of using a point-by-point scanner. One thing I have on my plate is exchanging that for a field-of-view scanner (probably a Livox Mid-40).

One interesting feature of the current setup is the ability to "zoom in" on details. With the microstepping mode of the stepper motors, one can take 2/4/8 times as dense measurements of an area if necessary. The limiting factor here is time. A single scan takes around 40 minutes with the current resolution (1800*300).

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PicassoCTs 1817 days ago
You could half it with a double header (one forward, one backward scanning at the same time)
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bruce343434 1817 days ago
quart it with a quadruple header!
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PicassoCTs 1817 days ago
Max resolution are the steps of the stepper motor per activation. (1.8° step-angle) https://datasheetspdf.com/pdf/1260602/Schneider/NEMA17/1

It could be increased by adding multiple distance measurement sensors in parallel per scan direction.

It could also be made more precise by adding a "sub-gear" that only turns within the frame of the step. But this would lengthen the scan process considerably.

To shorten that again, one could add the same scan head into the opposite direction.

At the moment the resolution is depending on the distance from the scanning device. Meaning the larger the distance, the more the angling distributes the points on a surface.

There are no real ways to mitigate that with a stationary device. Density can be improved though with rescans, using the noise to increase, although there the noise blurs the points along the line to the degree.

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dekhn 1817 days ago
Stepper motors can be microstepped (typically up to 1/32 or 1/64). In my experience, this works poorly as the microsteps are not evenly spaced. I find gearing works better.
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