Projecting an SLS system: Scanning precision

Write here about construction, ideas, equipment, tips n tricks etc. related to structured light scanning
mading
Posts: 307
Joined: 31 Jan 2017, 13:09

Re: Projecting an SLS system: Scanning precision

Post by mading »

Did some work.
Fusion was not exticing: various areas are not overlapped.
fusion_1.jpg
fusion.jpg
It ain't bad (1500-2), but I lack in alignement precision.
Do I have to work on scan quality (distorsion)? I guess wavyness is partially due to optical refraction of lights in wood. But misalignement here is an issue to be solved.
fusion_3.jpg
fusion_2.jpg
LG PF50, LG PF1500, RangeVision DIY: 2x DahengMer630, 2X12 and 2X16 mm 5Mp ZK lenses, RV turntable
3dxcan
Posts: 74
Joined: 02 Jun 2017, 17:21

Re: Projecting an SLS system: Scanning precision

Post by 3dxcan »

Scan the calibration panel after calibration process and send me the stl file. I'll show you how much distortion you're having.
Stive_Rad0
Posts: 35
Joined: 17 Jun 2017, 18:04

Re: Projecting an SLS system: Scanning precision

Post by Stive_Rad0 »

3dxcan wrote: 17 Nov 2017, 05:34 Scan the calibration panel after calibration process and send me the stl file. I'll show you how much distortion you're having.
Hi
Can I know how can you measure distortion by scanning calib panel?
3dxcan
Posts: 74
Joined: 02 Jun 2017, 17:21

Re: Projecting an SLS system: Scanning precision

Post by 3dxcan »

i use geomagic to determine the amount of deviation from plane you're getting on each side of the calibration panel.I call it the disortion map. thats a good indicator of the amount of distortion.
as an example this isnt a favourable:
Image
mading
Posts: 307
Joined: 31 Jan 2017, 13:09

Re: Projecting an SLS system: Scanning precision

Post by mading »

Many thanks 3dxcan.
ASAP I'll send you the stl.

Do you use also GOM inspect? I find it very powerful, fast and stable (and free).
If anybody in the forum is using it, I'll appreciate an indication of doing the same verification with GOM.
LG PF50, LG PF1500, RangeVision DIY: 2x DahengMer630, 2X12 and 2X16 mm 5Mp ZK lenses, RV turntable
mading
Posts: 307
Joined: 31 Jan 2017, 13:09

Re: Projecting an SLS system: Scanning precision

Post by mading »

Hi to all, I gave a tried to GOM inspect 2016, free version:

I have to check the perpendicularity of my panel: it is measured as 90.05°:
90.05°.jpg
Then I can fit planes (easy and straighforward):
Clip_4.jpg
Here you have deviations from fitted planes:
Clip_2.jpg
Clip.jpg
LG PF50, LG PF1500, RangeVision DIY: 2x DahengMer630, 2X12 and 2X16 mm 5Mp ZK lenses, RV turntable
3dxcan
Posts: 74
Joined: 02 Jun 2017, 17:21

Re: Projecting an SLS system: Scanning precision

Post by 3dxcan »

mading wrote: 17 Nov 2017, 09:24 Hi to all, I gave a tried to GOM inspect 2016, free version:

I have to check the perpendicularity of my panel: it is measured as 90.05°:
90.05°.jpg

Then I can fit planes (easy and straighforward):
Clip_4.jpg

Here you have deviations from fitted planes:
Clip_2.jpg Clip.jpg
as you see in the pics, you have a center of yellow and green (~0.05 divation) which happens to be accelerating out of the divation zone (-0.15) as you move toward the calibration edges, gray areas on the corner are our of tolerance zone (-0.15,0.15).Its a lens problem. someone with a decent lens should give us his result.
what size of calibration panel are you using? whats the format of the camera sensor (eg 2/3", etc) and lens? what type of camera? global/rolling?
mading
Posts: 307
Joined: 31 Jan 2017, 13:09

Re: Projecting an SLS system: Scanning precision

Post by mading »

camera spec (see previous post): http://www.oemcameras.com/dmk-23ux236.htm
aperture: around f12
lens: Cosmicar/Pentax 12 mm f1.2
panel: 110 mm
LG PF50, LG PF1500, RangeVision DIY: 2x DahengMer630, 2X12 and 2X16 mm 5Mp ZK lenses, RV turntable
Stive_Rad0
Posts: 35
Joined: 17 Jun 2017, 18:04

Re: Projecting an SLS system: Scanning precision

Post by Stive_Rad0 »

mading wrote: 17 Nov 2017, 08:20 Many thanks 3dxcan.
ASAP I'll send you the stl.

Do you use also GOM inspect? I find it very powerful, fast and stable (and free).
If anybody in the forum is using it, I'll appreciate an indication of doing the same verification with GOM.
by this method it is not defined the source of error (badly made calib panel or other sources). in all cases you may get the same deformation on mesh.
mading
Posts: 307
Joined: 31 Jan 2017, 13:09

Re: Projecting an SLS system: Scanning precision

Post by mading »

I agree there's plenty of room for further improvements, starting from panels.

Panels are made of:
-melamine particle board 19mm
-dots printed with inkjet printer on photographic paper
-paper glued with spray contact glue

I already found a visible deformation with my knife edge ruler.
Sorry for posting things on separate posts.

I could scan a "really flat" surface (less than 0.01 mm) and see what happens.
LG PF50, LG PF1500, RangeVision DIY: 2x DahengMer630, 2X12 and 2X16 mm 5Mp ZK lenses, RV turntable
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