V-22 Osprey Project - Prototype 1 Ending

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I'm calling an end to the first prototype build for this project.  A few things changed between the first attempted flights.  I gave the thing a serious diet by:

  • replacing the wooden boom with carbon fiber and redesigned/reprinted the motor mounts
  • replaced the separate ESCs with a 4-in-1 drone ESC module
  • replaced the Frsky X4R with a FrSky XSR
  • replaced the 2S 2000mAh battery with 2x 1S 600mAh batteries in series
  • replaced the Arduino Mega with an Arduino Micro
  • generally lightened everything up where I could
The new all-up weight is 217g, but it's still too heavy and the tolerances in these micro helis aren't good enough.  I tried a few hanging control tests, and there's so much slop in the control linkages that it ping-ponged all over and never stabilized.

For Phase 2, I have a pair of KDS 450 helicopters that I'd like to use for the next prototype.  They run on 3S 2200mAh batteries and are certainly more capable of lifting a larger airframe.  They are also more capable of doing damage, so safety is going to be paramount.  I think the control system is sound using the Arduino to mix the flight controller outputs.  Better tolerances should lead to less slop and more authoritative control.  Initially, I'd like to modify as little of the helicopter airframes as possible in hopes of returning them to separate helicopters if this prototype also fails.  The plans, for now, are to remove the tail rotor assemblies and figure out a way to connect them together with a fixed boom similar to my 1st prototype.  I've already checked, and it is possible to reverse the motor and the one-way bearing to have the two rotors counter-rotate.



Stay tuned for more!

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