If at first Quad didn't succeed, TRI TRI again

3689386384?profile=originalFollowing the death of the Ugly Pink Quad's 4th thruster, Entirely accidentally, I am going for a tri-rotor design, on 

a 1/4" plexiglas base, with 3 Futaba S3003 servos for vectoring thrust.

The Nano that was originally being used for the Ugly Pink Quad, and now the Tri, well...it died, so in comes the DFRobot RoMeo.


My initial idea is going to be to use the thrusts of the three ducted fan units to stabilize horizontally and control altitude, while using vectoring to produce the X-Y translations and yaw motions as needed.

Given the wide, flat body and the ability to vector thrust, I might be able to use the plexiglas as a lift-generating device to aid battery life when not merely hovering.

Given that lift, and position can be somewhat decoupled, it may end up a very stable platform for cameras and such, even in breezy conditions.


I hope to have the IMU stream stabilizing the platform by mid-week.

First test with the AFSoftwareSerial for COMMs with the ArduIMU seem promising.


E-mail me when people leave their comments –

You need to be a member of diydrones to add comments!

Join diydrones


  • When I was first thinking about it, I was imagining it as the aerial equivalent to a three-wheeled holonomic drive ground robot.  The math should be roughly the same.
  • I see your infected with "projectitous " too,,, looks like if u could make the front rotate in the same direction as the back two u could fly it like a plane and use the back two for yaw !!
  • wow looks alot beter then the pink foam flyer

    but like sabastian said you should improve the mount around where the ducted fans conect to the servo's as if you do a hard crash they look like the'll break off


    but over all it looks nice

  • Alex - Thanks!   That's a monster, over and above what I was thinking - It's a work of art.

    Ryan - Found a half dozen of these years ago, and planning to try using it with an OpenServo board as a light/fast linear positioner, but in the meantime, it's just feeding an analog input for thrust control during testing.  I find the linear pot gives a more sensitive feel than the rotational one that's controlling thrust angle.

  • I like the use of the motorized fader.
  • variable pitch projects.? you have to check out what mario is doing http://diydrones.com/profiles/blog/list?user=2vkqa8raz7ye1 
  • As a nod to the blade-pitch-wise comments, I have a question:

    Have any of you tried making quadrotors with variable-pitch props?

    I think it would be fascinating to take four RC helicopter tailrotor assemblies, run them at a constant RPM, and change thrust by varying pitch.

    One strong motor, centrally-mounted, could power the four props by belt drive, and four micro servos, together, would be lighter than the usual set of 4 motors with ESCs.

    What is more responsive?  Variable pitch with a 0.06sec tail servo, or variable speed on a constant pitch?

    See..........Incurable MultiProjectitis........ :-(


  • Since I am early in the development phase, I want the polar moment to be high.  It'll make the whole thing less responsive and twitchy.  As it gets nicely tuned, I can then concentrate the mass toward the middle, making it more agile.


  • @James

    I fell into this problem (and solution) as a child of 12.

    I was carving propellers from balsa and spinning them to make them fly (a unicopter) - at first a steep 45 degree incline.

    Then, for no other reason than because I had one, I carved a blade from a popsicle stick, as you can imagine - only the slightest pitch - and it turns out the popsicle was ever so much better for hovering, and flying horizontally than the 45 degree boat-props I had tried before - even though they were heavier - indeed heavier only helped. Trust my discovery at age 12 - you want a very modest pitch.


    At higher pitch you're losing lift to stall, and drag to wingtip vortexes (mileage may vary with ducts), but still you're an Airblender with that thing.








  • Cool toy.


    The closer everything is to the center of mass the easier it is to turn. You are trying to pivot a lot of mass with the ducted fans alone. I would move the boards, the ESC's and the battery to the center.


    You are pushing a huge amount of air with that large piece of plastic.

This reply was deleted.