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RangeVision DIY - my rig

Posted: 10 Feb 2021, 20:34
by mading
Hi there,
I start my post about the Rangevision DIY with a cheap and simple solution for stereo system with cameras with fixed angle, that can be used also in Flexscan or HP.
It's an Arca Style clamp, you can find in Aliexpress:
https://it.aliexpress.com/item/40004059 ... 4c4d4vsxP1
I printed a 2D view from the Daheng step file in common paper, and taped it to the clamps as a hole guide.
A few holes with a Pilar drill, and common M3*12 screws.

I had several issue with (more expensive) Arca style pan-head: very difficult to block at a desidered angle.
Good for taking pictures, not suitable for a rigid scanning rig.

Hopefully in the next week I will share the rest of the rig (as soon as I finish it)

Re: RangeVision DIY - my rig

Posted: 10 Feb 2021, 21:27
by pottersfriend
I've been looking at those but always thought they were too expensive to give it a try. I haven't ordered anything from Aliexpress before. Might have to try Aliexpress for that price. Looking forward to what you come up with. Did you also buy the rail from Aliexpress as well?

Re: RangeVision DIY - my rig

Posted: 11 Feb 2021, 17:31
by mading
pottersfriend wrote: 10 Feb 2021, 21:27 I've been looking at those but always thought they were too expensive to give it a try. I haven't ordered anything from Aliexpress before. Might have to try Aliexpress for that price. Looking forward to what you come up with. Did you also buy the rail from Aliexpress as well?
Hi there, I think I bought the Arca pan head branded "Haoge" and rail at an ebay shop in 2018 or before:
https://www.ebay.it/usr/twinklefoto
Items are still listed, even though the shop looks empty.
I DON'T suggest their pan-head for scanning.

I think any decent rail will do its job. Mine is 40 cm, the longest I could find. That's probably not enough for large FOV.

Re: RangeVision DIY - my rig

Posted: 11 Feb 2021, 17:45
by OBNRacerMan
If you look at the recommended distances, then for the largest Rangevision DIY table (zone 1), then 40 cm of rail is more than enough (in any case, if the object is too large, you will need to scan in parts and, preferably, using markers)
Recommended distances between cameras and distance to tables
Recommended distances between cameras and distance to tables

Re: RangeVision DIY - my rig

Posted: 11 Feb 2021, 18:05
by mading
Don't laugh.
Only now I realized I always looked at this graph upside down...
That's good to know. I am not going to scan cars for now.

Re: RangeVision DIY - my rig

Posted: 18 Feb 2021, 12:17
by mading
Today I tried scanning a very dark (and bit reflective) ebony chinrest with Rangevision.
With long exposition time and double exposure it's possible to get most of the data from the object.
2021-02-18 12.15.04.jpg
Automatic turntable works wonderfully.
Coming from HP3D+AutoIT+Arduino makes you appreciate these things even more.
Alignment is made during the scan, that makes all the process automatic.
Immagine 2021-02-18 131302.jpg
Immagine 2021-02-18 131245.jpg
Only a final registration is needed, but it doesn't take not a long time (a few minutes).

Projector: the low-brightness LG PF50Ks. moving to the LG PF1500 could speed up.

I tried the blue light option with filters, but did not have the time to properly set-up the thing.

Re: RangeVision DIY - my rig

Posted: 04 Mar 2021, 17:56
by mading
Another ebony chinrest.
Almost all the surface was captured.
-16*2 scans

exposure was 750ms for the ebony, and around 150ms for the brighter parts.
Medium calibration panels is OK for these objects (for the accuracy I need).

I am interested only in the wooden part of the item.
But it's still interesting to see that the bright M3 thread was detected.

Simplification and rendering performed in Rhino 7.
The QuadRemesh tool is really promising for dealing with organic objects, together with SubD surfaces.

Re: RangeVision DIY - my rig

Posted: 10 Mar 2021, 12:21
by martan
Looks amazing!

Is the finished result a solid (ie exportable to STEP etc)?

/M

Re: RangeVision DIY - my rig

Posted: 10 Mar 2021, 13:46
by mading
Thanks Martan.
This is not a proper reverse engineerined part.
I consider the Quadremesh command as a very useful tool for data compression and for making things easier for the CAM step.
The previous pictures refer to a quad mesh: surfaces approximated by quadrangle mesh.

In a few clicks you can convert the quadrangles into subD or Nurbs surfaces and export the geometry as step files.
Nurbs (and step files) after conversion are far more complicated (huge number of control points).
Yes, everythig hese is solid, starting from the mesh.

My next goal is to reverse these shapes with a limited number of (editable) SubD surfaces.
A note on subdivision surfaces:
https://en.wikipedia.org/wiki/Subdivision_surface

the mesh from RV after editing
ViewCapture20210310_143709.jpg
Quadrangle mesh:
ViewCapture20210310_143658.jpg
SuBD surfaces (with such a mesh density it looks almost like the quadmesh, a bit smoother)
ViewCapture20210310_143722.jpg
Nurbs (or a step file) as from automatic conversion from SubD:
ViewCapture20210310_143731.jpg

Re: RangeVision DIY - my rig

Posted: 11 Mar 2021, 06:46
by martan
Thanks Mading.

Watched a few videos with Rhino on YouTube and it looks nice. Quadremesh and SubD.
Maybe I should give it a go.

:)