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.