Brocopter Y3: foldable mini tricopter

Author: KipK, published on 2014-08-10

Click this button to get the 3D model


This is a mini 250 foldable tricopter dedicated for fpv.

Parts are available on Shapeways here

RCGroups thread
If you feel generous enough, you’re welcome to make a donation.

Yaw mechanic is protected between the center plate, the whole rear arm turn itself. ( )

2 camera configuration possible:

  • FPV cam on top with Mobius between plates. There’s a hole to access the mobius button from the bottom plate.
    This way you can tilt the fpv cam a bit.
  • FPV cam between the center plate and Mobius and the anti vibration mount on the top.
    Motor mounts are for Tmotors 1806 & clones ( I use RCTimer ones ) , or you can use the bigger one that fits for Sunnysky 2204 & co.
    Use 6″ props with 3S or 5″ with 4S.

You’ll need small ESC, there’s not much space on this little beast. Kiss esc are perfect for that.

Here’s a video of the yaw mechanics:


Most parts are printed with 0.2mm resolution.
Motor mounts & arm mounts needs supports.
I print the Yaw_arm_horn.stl with 0.1mm, it’s better, but not necessary.
You can also print the center plates it works good, but it’s better to cut them with cnc using G10 or Carbon.
You’ll also needs:

  • 2x 19x10x7 bearings for the yaw axis
  • 1 micro servo ( the one I use is MKS DS450 22.5x10x23.5 mm )
  • some 10mm carbon tubes
  • M3 screws: 4x45mm , 4x30mm , 2x15mm
  • 10xM3 nuts + 2 threadlock M3 nuts.
  • 3.5×3.5 flight controller
  • 25×25 fpv camera or Mobius cam or booth.
    Cut 2x90mm carbon tubes for front arms, and 105mm for rear one if you use 5″ props and want it minimal, or 2x100mm fronts & 1x115mm rear for 6″.

Add a bit of tape on the end of the tubes to give some friction on the motor mounts and front arm mounts. This is quiet sufficient to fix them and will prevent breaking some parts in case of crash ( mounts will turn absorbing a bit of the shock ).

License: Creative Commons – Attribution – Non-Commercial

Tags: fpv, multirotor, quadcopter, tricopter