#video about #3D-printing a whole #flying drone, “even the motors”, using 3 kg of filament, but evidently they’re wound with regular copper wire and using steel cartridge ball bearings and steel nuts and bolts and, originally, a steel 8mm shaft and collar, which he replaced with (brass?) heat-stake inserts and a precision-ground steel shoulder bolt. The motor’s magnetic core is, however, 3D-printed using “magnetic PLA”. He’s also using (rare-earth?) permanent magnets. The dovetailed arms (evidently designed using #topology-optimization, and vastly overspecced) are held on with a very interesting plastic twistlock design. He measures the thrust as ≈3kg of weight (≈30N) using a US$8 load cell from Amazon, but the motor took 2½ seconds to spin up to full thrust rather than the 800ms for a much smaller comparable-thrust off-the shelf all-metal type. By #Michael-Rechtin. #mechanical #manufacturing
on 02024-06-25#video on #3D-printing a #flying radio-controlled model Orca tricopter (three ducted fans) from Command & Conquer with #topology-optimization and nylon powder “multijet fusion” which sounds like it doesn’t involve any jets at all. No notes on the electronics or software.
on 02024-06-25the #topology-optimization group at DTU
on 02021-05-29introduction to #topology-optimization with applications to selective laser melting (SLM) #3D-printing
on 02017-03-11#video of ForcePad, a GPL free #FEA and #topology-optimization app with real-time feedback on a 2-D design; I think it uses CalculiX. Abandoned since 2008
on 02017-01-16#video of the non-free #topology-optimization app published by DTU with real-time feedback on a 2-D design
on 02017-01-16a #PDF of a super widely cited 2011 #paper on #topology-optimization for #3D-printing, showing some results they got with graded density etc.
on 02016-09-22This 2008 #paper on “Design for additive manufacturing of cellular structures” has the best diagram I’ve ever seen of the octet truss (aka fcc crystal structure). They’re doing #topology-optimization of #metamaterials using “particle swarm optimization”, which I hadn’t heard of before, but apparently it’s a cooperative variant of genetic algorithms. They’re apparently doing this to optimize “morphing airfoils”, but their final results are not very impressive.
on 02016-09-22#pdf #paper on automatically modifying #topology-optimization results for #3D-printing (in this case, FDM), which mysteriously doesn’t seem to have considered incorporating the #manufacturing constraints into the objective function.
on 02016-09-22#pdf dissertation by Benjamin Vayre in French on #topology-optimization for #3D-printing by electron-beam melting, with a bunch of interesting-looking results. Mentions the acronym DFAM, “Design for Additive Manufacturing”. Mentions topology optimization. Proposes the following design process: analysis of specification → initial form generation (either manually or through topopt) → choice of orientations during manufacturing → geometry optimization → validation → maybe start over. Apparently the dude designed a mounting bracket for his dissertation using off-the-shelf software at the University of Grenoble. I guess not every university can afford to have standards. They have a wicked mounting bracket and e-beam melter though.
on 02016-09-22#pdf #paper on #topology-optimization for hyperelastic materials. From glancing at the figures I’m not super impressed with their results, though they sure do have a lot of math. Apparently the authors think “Neo-Hookean” is a person, although at least they managed to avoid citing any papers by him.
on 02016-09-22#pdf #paper with lots of results of #topology-optimization made by #3D-printing. They wrote and published a MATLAB program called TOPSlicer to translate topology-optimization results to useful formats. #manufacturing
on 02016-09-22#pdf #paper on “Multiple-Material #Topology-Optimization of Compliant Mechanisms (#mechanical #flexures) Created Via PolyJet #3D-Printing”. It says that multiple materials has the potential to eliminate the need for thin, weak sections. (PolyJet is a process that selectively deposits either of two liquid resin monomers and polymerizes them with UV. One of the resins is an elastomer.) Their results do not seem to justify that level of enthusiasm, as they still contain thin, weak sections, and they don’t seem to have measured the output force. #manufacturing
on 02016-09-22#PDF #paper on using multi-objective #topology-optimization for #metamaterials (“finite periodic structures”) for things like stiff heatsinks (solid #heat-exchangers). Cool pictures. #toread
on 02016-09-20a #paper about something like #topology-optimization for #tensegrity structures (i.e. structures that incorporate preloads).
on 02016-05-22Ole Sigmund’s widely-cited “99 line #topology-optimization code written in Matlab” from 1999. Elsewhere there’s an 88-line version that’s a lot faster, but the description refers to this version. #smallisbeautiful
on 02015-12-30#topology-optimization #software for #3D design and #manufacturing, in Python. MIT X11 license.
on 02015-12-10