Wednesday, May 26, 2021

User Friendly 3D Scans and Photogrammetry (Mobile Apps)

Wow, the user friendliness and speed of this app is just amazing. A long way in ease and useability from the open source tool chain I've used previously.

Wednesday, January 6, 2021

Stanford Center for Turbulence Research 2020 Annual Briefs

Center for Turbulence Research Annual Briefs

Tuesday, January 5, 2021

Machine Learning for Fluid Dynamics: Patterns


The data set he mentions is Johns Hopkins Turbulence Databases. Many hundreds of Terabytes of direct numerical simulations with different governing equations and boundary conditions.

Wednesday, November 11, 2020

Missiles and Rockets

Missiles and Rockets was a magazine that ran from the mid 1950's to the mid 1960's at the height of the Space Race. All the issues are available on the internet archive. It's neat to see some of the old concepts (like the manned rocket bomber above), and the advertisements in the early issues by companies trying to hire engineers and scientists so they can cash in on the flood of funding in the early gold rush days are pretty entertaining.

Tuesday, April 21, 2020

Octet Truss Cube: Printability Update

This little octet truss example cube moved from "First to Try" to "Successfully Printed" on my Shapeways store. They estimate a greater than 80% success rate on the print (thanks to whoever ordered the part!).
I knew it could be printed since I had previously printed versions of this design, but Shapeways updated their print-ability guidelines since then. Nice to see it still works!

Thursday, March 26, 2020

NeRF: Representing Scenes as Neural Radiance Fields for View Synthesis

This is really cool. The capture for the specular reflections is great. I'm excited that something like this could be really useful for better photogrammetry. For instance, see this old GBU I did a long time ago. The reflections off the shiny metal cause artifacts in the point cloud reconstruction.

There's a paper, a project summary page with more views, and a github project page for the code as well.

Saturday, April 6, 2019

3D Shape Segmentation With Projective Convolutional Networks

This is an interesting summary of an approach for shape segmentation. I think it's pretty cool how often VGG-16 gets used for transfer learning with good results. It's amazing that these models can represent enough knowledge to generate 3-D surfaces from single images. (I also like how many folks use airplanes as examples : - )

There's a website for the ShapeNet data set that they used as a benchmark in the video, and this paper describes the initial methods folks developed during the challenge right after the data set was released. That's a pretty neat approach. It reminds me a bit of the AIAA drag prediction workshops.

Sunday, March 31, 2019

Fun with Machines that Bend

I really like his 3-D printed titanium part at about the 8 minute mark, and the chainsaw clutch at minute 10 is pretty neat too.

The eight "P's" of compliant mechanisms:
  1. Part count: reduced parts count with bending parts instead of hinges and springs
  2. Production processes: lower price through processes like injection molding
  3. Price: lower because of reduced parts count and affordable processes with reduced assembly
  4. Precise motion: no backlash (yea!),
  5. Performance: no need for lubricants, reduced wear
  6. Proportions: can be made at small scale with photolithography
  7. Portable: lightweight
  8. Predictable: the operation of the mechanism can be well-known and reliable

Wednesday, March 27, 2019

Engineering Sketch Pad

I haven't heard of Engineering Sketch Pad (source code as part of OpenMDAO, and here) before, but this is yet another NASA sponsored open source tool that could be useful to you for aircraft conceptual design. I read about it in a post on Another Fine Mesh about some interesting research the folks at Pointwise are doing. It reminds me of, but is different from, Open Vehicle Sketch Pad.

There's a seminar on the software given by one of the developers up on a NASA site: The Engineering Sketch Pad (ESP): Supporting Design Through Analysis. (yea, DARPA!)

It has some neat features that make it useful to support high-fidelity analysis. It creates watertight geometry, it can carry attributes with the geometry that could guide mesh resolution, it does "conservative" data transfer for discipline coupling (match a solver's numerical scheme), and most of its parts are differentiable which is useful for optimization.

I added this to my list of Open Source Aeronautical Engineering Tools.