Round tubes are back.
The goal of this build has various missions:
1) show how easy it is to build a ship on par with commercial ships.
2) stay aloft for over 30 minutes carrying a full-size camera.
3) use low Kv motors and low voltage to create an efficient ship but stable camera platform (a design that is usually contrary to the objective).
4) fly at slightly less than 200 Hz but also be able to fly at 200 Hz (the evil frequency) to test the impact of doing that when vibrations are only managed by frame stiffness and low mass.
5) test light methods to mitigate the more fragile cloth/woven carbon tubes.
6) test APM code flexibility on flying a new octa motor layout.
After a successful test using braided carbon fiber tubes that are basically indestructible, strong, stiff, light, and provide a surface that is easy to bond, this discussion will focus on using cloth or woven carbon fiber tubes. Relative to braided tubes, woven tubes have a smooth surface (not as easy to bond), have a lower resin content, and layered fibers. Braided tubes use fibers that are braided from the inside layer to the outside layer. Woven tubes stack and bond either cloth or tape layers placed in multiple directions to derive engineered stiffness and light weight. But unlike pultruded (where most all fibers in one direction), there are axial fibers to keep cracks from propagating. Why not just stay with braided? Woven carbon tubes are more available, come in more sizes, and are lighter for their stiffness.
This discussion will go from design through flight tests.