a newish #video #toread by Eirik Brandal about #free-form #electronics sculpture
#Segerman #video #toread about a pseudo-scissor linkage #mechanism using gears instead of half of the links
#video captured on a home security camera of a meteorite hitting the ground and smashing
#video on #materials with “dilatency” such as sand, where compressive stress increases their volume
#Hyperspace-Pirate #video on #bootstrapping/#manufacturing a #DIY #jugaad #X-ray #radiography machine #toread
#Hyperspace-Pirate #video on #bootstrapping/#manufacturing a #DIY #jugaad CT-scan #tomography #radiography machine (using a donated dental #X-ray machine and an “intensifier screen”) and #3D-printing the results. He triggers his phone’s camera app with a spring-loaded pin controlled by an Arduino-triggered relay. Lowest power setting is 60kV, 4mA. He hacks the images with the GIMP to get reasonable grayscale, then feeds them into the open-source “3D Slicer” to try to do computed tomography, but it didn’t actually do tomography, just meshing once you’ve already done the tomography, so he used a “cone-beam backprojection tool by Stanislav Maslan” for that. The result is pretty noisy but he can 3-D print it. He scans a frozen dead rat, a star-shaped squash, a frozen sardine, and a large fish head.
#X-ray #radiography #toread: “An X-ray image intensifier (XRII) is an image intensifier that converts X-rays into visible light at higher intensity than the more traditional fluorescent screens can. Such intensifiers are used in X-ray imaging systems (such as fluoroscopes) to allow low-intensity X-rays to be converted to a conveniently bright visible light output. The device contains a low absorbency/scatter input window, typically aluminum, input fluorescent screen, photocathode, electron optics, output fluorescent screen and output window. These parts are all mounted in a high vacuum environment within glass or, more recently, metal/ceramic.”