Dimensional accuracy test

Again zero prep [Feature mode] - just playing. Red = Scan / Lines = CAD model I generated from a CMM / digital calipers. Steel hub, so lots of reflection and uniform edges / features so should have been done in [marker] mode and better lighting. However, POP captured the dimensions of the object nicely. The scan also showed that I missed off a chamfer, which is exactly why I bought the scanner!

Part is ~ 150mm in diameter, accuracy I tested was approx 0.2mm.
Very impressive.

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I am happy to admit that I was wrong, wrong, wrong about the following assertion (after the break).

I misinterpreted a statement by Revopoint on the Kickstarter Comments page that I would need a mechanical CAD program to measure the 3D scans that the POP produced. I took this to mean that I would have to scale the object (which Handy Scan/Studio don’t do) to get the desired results.

Turns out, that statement was due to the fact that Handy Scan/Studio do not measure objects.

My bad.

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The technology used in the POP does not support dimensional accuracy (this has been confirmed by Revopoint personnel).

I expect that your results are due to a happy accident of placing the POP the right distance from the scanned object and the Structured Light design of the emitter pattern just happening to be on a metric grid (they had to choose some initial dimensions for the design, so a grid size of, say, 0.1 millimeters is more likely than, say, 0.075 millimeters).

The takeaway is this: do not expect to get your resulting scans in millimeters!

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Not true I’m afraid. Done multiple scans today, same accuracy. Biggest scan trying the marker feature was this 18" magnesium wheel (again scan in red, bounding box is the manufacturers data!). This is the raw data, un-scaled.

It’s not the best scan I could do better by a long shot, I’m still testing, and yet it’s still very accurate, the bolt PCD is spot on. If yours isn’t able to do this there’s something wrong with it :wink:

The ability to generate a model with 1mm / meter accuracy is the reason why I bought this thing and it seems to be well within that limit.

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You keep saying this, and yet people keep having “happy accidents.” Repeatable happy accidents.

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yeah, my scanner “accidentally” had perfect fit when 3d printed a part directly modelled over an automotive scan - it was friction fit- id like to test more but it seems accurate to me- I will update this space in the future if my findings change.

Its not hard if you think about it- we know the constants- The Field of view of the cameras- the distance from the cameras- its pretty difficult to not get the correct scale of objects with basic math