Sigma Flight Theory 250

By jsnodgrass on Oct 06, 2016

6  269  4

This is my own design, built with my very own Theory 250 frame. I had wanted to get into FPV racing for a while but when it came time to build a racer, most of the frames on the market didn't meet my requirements. These were:

  • 250mm size
  • 6" props
  • Lightweight
  • Aerodynamic
  • Clean design, with few wires showing

Since I already had the tools to design and machine my own, I decided it should be my next product and I set to work. The result is a unique tubular design with a base weight of just 78 grams, a compact yet usable layout, and excellent aerodynamics and balance. Most people underestimate the importance of locating the battery above the motors to place the center of mass directly in the plane of the props. It is the single most important consideration for maximizing the agility of a given size quadcopter.

The second most important thing is ESC location, which is partly why I chose to go with a 4-in-1 installed as part of my board stack. I don't understand why these haven't caught on more, since locating the ESCs on the arms underneath the props reduces angular acceleration, blocks airflow, and just looks messy.

Photos

Discussion

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RJFeddeler   Oct 07, 2016  
1

Hey, thanks for liking my build!
Your quad is amazing. Looks beautiful and it's so cool that you custom built the frame. I'm more into the software side of customization but mainly because it's all I know how to do :) I would love to try building something like that in the future.
Anyway, great work!

jsnodgrass   Oct 07, 2016 
1

Thank you, really, but your work is more impressive. I mean, you developed your own flight controller. How could I not like that? Truly impressive stuff, and inspiring. It makes me want to dig into the Betaflight code for myself even though I have very little programming experience. I can't imagine taking on the task of developing my own flight controller like you did though. Just awesome.

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