Project Dualcopter – worklog #4

More than a year after staring this damn project, I finally decided what goes where. And on top of that, short description how Dualcopters works (or at least should work).

  1. There are two counter rotating propellers on top. They are responsible for thrust and YAW control
  2. When both props turns faster, dualcopter gains altitude
  3. When clockwise propeller turns faster, whole design starts to rotate counter-clockwise. When counter-clockwise propeller turns faster, it rotates clockwise
  4. Roll and Pitch axis control is archived by two flaps at the bottom of the design moved by two servos
  5. Since propellers are always rotating, there is almost always enoughair passing through flaps to have enough force for stability control and maneuvers
  6. To generate enough torque, center of gravity should be far above flaps. This way, even relatively small force on an end of long lever, there is always enough torque for roll and pitch stability

Dualcopter working principle

Keeping above in mind, it will look like this:

Dualcopter what goes where

What is still missing? Place to put battery in and electronics. Next update as soon as I will have any update 😉

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Project Dualcopter – worklog #3

It's been exactly one year since my last update on Project Dualcopter. On 20th of October 2016 I've posted that there was a progress. Now, 12 months later, I once gain report, that there was a progress…. That was slow….

3d printed dualcopter aka flying bucket

servos for 3d printed dualcopter

  • I've finally installed control surfaces and servos
  • I've finally decided where LiPo will go: to the top of the whole stack. I want CoG as far from control surfaces as possible. They will not generate much force, so I need as much torque as possible. So, long lever FTW
  • My daughter called it Flying Bucket. Makes sense, right?
  • Plans for next week: battery mount

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Project Dualcopter – worklog #2

3 weeks after my first post on Project Dualcopter, it's time for small update. The plan was to install servos and control surfaces. Instead, I've done:

  • Basic electrical wiring for motors and ESCs. They have power now and are ready to be connected to flight controller
  • To level shelf (above propellers) designed to hold flight controller and radio receiver
  • Think for a moment about landing gear. Yeap, there will be some sort of shock absorbers
  • Think for a moment where battery will be placed: as low as possible to keep center of gravity below center of thrust
  • Decide which propeller should run clockwise and which should run counterclockwise: top should go clockwise, bottom should go counterclockwise

dualcopter esc soldering

dualcopter esc

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Project Dualcopter – worklog #1

Flying season 2016 is slowly coming to an end on northern hemisphere. That means less time spent on an airfield and more time spent behind a desk. For this autumn I've found a very interesting, small project: Dualcopter.

Dualcopter is an UAV with two coaxial contra-rotating propellers and 2 control surfaces driven by servos. Lift and yaw are controlled by propellers, while pitch and roll by ailerons placed below motors. This video illustrates how it looks like:

My Dualcopter will be slightly different. Instead of foam and wood I will use 3D printed parts connected together CA glue and zip ties. Maybe it will not be super strong and probably will not survive any crash, but should be enough to make it fly for a minute or so. Almost all parts would be either 3D printed or taken from spare box. I'm not planning any new purchases.

Planned specs:

  • Motors: Turnigy MT2213 935KV
  • Props: APC 1045 MR
  • ESC: Afro 20A
  • FC: Flip32 probably with INAV inside
  • Battery: 1300mAh 3S
  • Weight: around 800g with battery

dualcopter 1

So far, after 2 evenings I have this:

dualcopter 2

Two motors mounted on a frame.

Next step would be to build bottom section with ailerons and battery compartment.

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