Meet prototype number 3 of SafeTdrone



Hello fellows DIYdroners,

Its been a long time since my last post and just to reintroduce myself let me point you to my first post: I was already crazy...DIYDRONES made it worst ! The story...part 1 and part 2  here.

For our fan's club of the time here is an update:

Our last CNC machined, carbon fiber prototype was a piece of art and during initial power run test a major design flaw showed itself. the center small t-rex 450 tail rotor gears were shearing shaft. We decided to upgrade to t-rex 500 tail rotor gear but it required a brand new hub design. At that time, 3D printing was the new kid on the block so I decided to drop the stress of carbon fiber CNCing and learn a new trade. WOW! I love 3D printing. Here I was again, stock in a new passion with a steep learning curve (3d drawing and the challenges of 3D printing. After countless hours of 3D printer buzzing sound and so many boxes of all kind of  failed,wrong,broken ABS parts, I would like to consider myself and intermediary to advanced 3D printer operator. So, our fully 3D printed, variable pitch, dual motor quadrotor is taking form. The project was not dead, just re-engineered. BUT... I found myself in a new project that requires a multirotor which would be safe to operate, easy to fly and easily upgradable to a more mission oriented airframe. Should I also mentioned that I like to have a WOW factor in what I built. Anyway, the variable pitch quad is resting on a shelf but won't be abandoned. Just a little delayed. You can see some pictures of it on my flickr page which I linked below.

And here a quick picture:


Now, I would like to introduce Prototype number 3 of my SafeTdrone.

In this video you can hear a rattle sound which I later identified has to soft propellers bending and causing tip stalls.

Before I list prototype number 3 specs, I invite you to see a video of prototype number 1 below:

SafeTdrone prototype number 3 specs:

- Modular fully 3D printed airframe

- Sunnysky X2814 1250Kv

- Castle creation talon 90 ESC

- 3 bladed Master Airscrew 9 X 7 propeller

- 3DR pixhawk, GPS, telemetry and power module

- Qty(4) battery bay with ample volume for various battery size and configuration (up to 4P configuration)

- weight without batteries: 2445g

- the approximative thrust per propulsion unit is 1.8 kg

The above video flight configuration was with Qty(2) 4s 3700 mAh zippy compact weighting 355 g each and at that time, 3 blades 9 x 5 GWS propeller were used.

Mix flight time was 6 min. down to 20 percent batteries capacity.

On a later flight, I added two dead lipo's in spare battery bays just to see the lifting capacity. At that time batteries weight would have been 1325 g for a total take off weight of 3570g . It would represented about 20000mAh of batteries capacity. The quad was able to fly and climbing was still positive although I did not flew it aggressively. Further test are coming up.

Here is a link to my flickr page where you can see other videos and some pictures:


Variable pitch Quad

Please let me know your impressions, recommendations....



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  • MR60

    Nice. I prefer prototype number 1 though. Looks less susceptible to lateral wind.

  • Cool design..

    but prop cover is too limiting efficiency of motors.

    Try something thinner for prop cover.

    Do you plan a production ? 

  • Developer

     yes it maybe heavy (not everything is about big flight time)

    I'm not trying to emphasize concern for flight time, but the extra aerodynamic effects that reduce the stability of the platform due to wind. see link for comments. I hope that can help with future prototypes achieve the desired outcome. :-)

  • Very cool! There is a market for it. GOOD LUCK!

  • Never mind the quads  the Raccoon's are cute !!

  • well done mate..  you made a safe drone and you achieved it..  yes it maybe heavy (not everything is about big flight time) and you may crash it etc etc blah blah ..your design looks solid and would suit a heap of applications..

    well done.. most peeps look for why nots and don't really get the uav for the application approach not the 1 drone fits all..

    are you releasing the stl's? or will you produce?

  • Cool design but simply Covering up the spinning props doesn't make it safe. Most times when they crash the props stop spinning and the do so quickly because there is very little inertia unlike am rc helicopter with a large main rotor. The unsafe aspect is a heavy weight falling out of the sky on someone's head and injuring them.
  • Developer

    It just looks too heavy. sorry, its admirable since this is an area of innovation that is required. Safeflight copters went from a design like this to something like this the later was cheaper to build, but lacked the simplicity of the original design.

    And Randy in trying to configure the production version of the safe flight copter found issues with the aerodynamic effects of the cage effecting performance (ignoring building issues as the production model became too complex to build for most) And by performance, it's not just thrust loss due to guards, but it becomes much more susceptible to wind.

  • How can I get my hands on one of these? I want an all black one ;)
  • I want one...
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