New patented tilted coaxial VTOL




Here is a video and a 3-views drawing explaining the mechanism of a new tilted coaxial system.

The machine has a frame, and a motor comprising a lower output shaft and an upper output shaft. A lower assembly of blades is fixed to the lower output shaft, and an upper assembly of blades is fixed to the upper output shaft. An orientation module is mounted on the frame, and the motor is fixed on the module. The module includes an orientation unit to pivot the motor around a pitch axis and a rolling axis. The orientation unit comprises a plate mounted on the frame via a pivot link around the pitch axis.


Components embedded in the drone:

- Camera Fatshark Pilot HD

- 200mw 5.8Ghz Tx with Spironet antenna

- 2 JR DS385 sub-micro digital servos

- 1 contrarotating bruhsless motor Maxxprod CR 2805

- 2 ESC brushless 10A

- 1 Lipo Battery 3S 2200 mah

- 1 flight controller uPilot32 (VGR-Systems)

- 1 Graupner Rx for command input


Weight: about 500g

Flight time: 10-11 minutes


The main advantage of the system is the size: features of a big quadcopter but ccarried in a bag pocket.


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  • Of course Paul, i'll do it! Thank you for your advices!;)
  • As you agree on my comment, I don´t want to be impolite anymore.
    Wish you lots of success with your project. And stay open minded on many ideas, not focussing on patents

  • Paul,

    You're right, this kind of flight dynamics is not new but when you try to replace your guy by servos in order to miniaturize you have to find a solution. This patent proposes a solution to orient the CR motor with a system of swashplates that preserves command's precision (with 2 arms for each servos and separate control for pitch and roll) and yaw authority on the frame. and don't worry, my energy goes to improve again and again the device!! :D

  • VGR-Systems,

    In terms of flight dynamics it is the same. You have a counter rotating propeller and you shift a weight below the thrust vector. The man is using his arms to shift the weight, you take some servos. His arms doing the commands.

    At least it is your decision putting lots of energy into a patent. But if you do not claim a patent for new flight dynamics, neither for servos or pivot points...

    I personally hope you will use your energy improving your device.

  • Paul,

    Actually, this system is already patented since 2011 (published 2013).

    Ouroboros is right, a patent is just a new solution to a problem. The problem was: how to use a CR motor to stabilize and control a vtol on the 3 axis. The solution is to tilt it with two swashplates and commands like servos. your exemple have no swashplates and no commands, it's a guy who tilts itself the entire's not the same system.

  • Skybotix coax appears to be a single propeller swashplate design though, not double swashplate, and isn't doing propeller shaft/mast pitching/rolling. As for the single motor assembly here, it's more like a convenient integrated frame for two coaxial but otherwise conventional motors.

  • Nice little project! And nice to see it is flying well.

    But I think it is not possible to claim for a patent. Here is the exact machine a bit bigger.

    Stick to the nice concept but keep your feed on the ground (patent...)

  • Hi VGR,

    Very interesting and mechanically simple design.

    Please correct me if I am wrong, but you actually seem to be using "pendulum effect" to control pitch and roll.

    Your prop center of thrust is well above your CG and without tilting the rotors provides for level "hovering" flight, with yaw controlled by varying the motor speed between the top and lower prop.

    But when you induce motor/prop tilt in order to cause pitch or roll you are in fact changing the CG in relation to the prop thrust center and relying on the pendulum effect of the movement of the CG of the copters chassis to produce the necessary offset of the prop angle producing the desired pitch or roll.

    Obviously lowering the CG would permit the chassis to stay more level during pitch and roll, but it would still be offset based on the current design.

    In order to have the chassis actually stay level, it seems to me you would need a double pivot, one for the motor prop and a second one for the Chassis, in effect, a double pendulum.

    However, if the second pivot was a free hanging pivot it would suffer from inertia induced forces (accelerating and decelerating, so still wouldn't actually stay level under normal flight maneuvers.

    Just thinking about it a bit.



  • Thanks David !

  • Oleksandr,

    No heavy pendulum effect with this kind of frame (horizontal frame). An aerobatic flight can be achieved.
    I've got another prototype/frame which uses the pendulum effect to level the frame (vertical frame). No need of expensive and heavy gimbal system because the camera is leveled, even during translation. It's not aerobatic but maybe more adapted to aerial video. This proto uses a camera gopro, lip 4400mah and flight time 12min. I'll post here some info ASAP.

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