Monthly Archives: June 2011

Poor man’s IrDA for intermodular communication

If all goes extraordinarily well, the AUV will have the following modules sitting in the hull:

  • Acoustic modem
  • Motor control
  • Depth control (buoyancy control and pressure sensing)
  • Master controller

Rather than wiring everything together, I plan to give each module its own power supply and use an optical communication protocol to connect the modules to the master controller.  The inside of the hull will be cleaner and more solid than if everything was wired together, and waterproofing will be easier.  Here’s how it works:

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Sure enough, ReplicatorG reads 123D-generated STL files at 1/10 scale

Update: 123D beta 5 uses the proper units for exporting STL files, so the scaling operation is no longer necessary.

As I noted previously, objects in STL files created by Autodesk’s new 123D CAD program are not correctly scaled when loaded into ReplicatorG (at least not for me, I’m using the public beta from a few weeks ago).  Eyeballing it, I guessed the object in RepG was about 1/10 the size defined in the 123D model.

To test this hypothesis, I designed a rectangular prism, 50 mm by 25 mm by 10 mm (yes, the temptation to go 90x40x10 was strong).  Results follow:

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