Limb scanning experiment
@ Bootcamp, Fablab Norway:
For the prosthetics program, I wanted to learn more about 3d scanning since one major improvment would be to have the ability to produce good 3d scans from limbs. These could then be send to another country with orthopedic specialisme to make the nessesary shape changes, send it back and it then can be milled out locally.
The next engine 3d scanner costs 3000$ and has HD hardware,
+ scan and stichsoftware all in. Still a good computer with dual processor, very good graphics card and 3GB Ram is still required for smooth operation. Add another 1000$ or so for a complete scanning station.
In order to scan a limb 360ยบ in 6 steps, I needet to invert the scan system, thus the scanner is now turning around the limb. you can download the turning tool below, which I made from scrap.
With a proper nonius ring, you can scan fairly precise. For the best results, the whole scanning proces should take place inside a cylinder like the sketch above.
Important. In order to stich the limb together, it is wise to cut some small dots on the vinyl cutter, to be able to make marks on the stomp. Ones the lighting and the marks are optimized, I beleive very good results can be achieved. The resolution it requires in order to built a good plaster positive, is not determined yet. I was a bit shocked the the stl file was 82.8mb. That is way too much for the purpose.
Here a overview of the scan/stitch software with all the limb scans:
It works quite nice whith stiching, but only if you have some good marks on the scans, which you then can define orientation points. However, I have to say its still very difficult to stich a limb tohgether.
The next scanner engine is an atractive system with software and everything ready to operate. Still presented as a low cost scanner compared to other models, the price of 3000$ is to expensive for the purpose we need it.
I will look into DIY kids like the david scanner or the intricad system.
Is it possible to produce a good 3d scanner for orthopedic limb correction under 500$? I am not sure yet...
download the files to create the turning mechanisme:
