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Cleo Robotics Demonstrates Uniquely Clever Ducted Fan Drone

spectrum.ieee.org

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Re: Cleo Robotics Demonstrates Uniquely Clever Ducted Fan Drone

#11

Post by hedgehog »

sterlind wrote: post #4

Perhaps the attitude of each fan blade rotates independently. To angle the drone, say, forwards, the fan blades might angle flat when they're at the forward position, every cycle, and angle tilted at the backwards position? Seems expensive and tricky though.

"An Underactuated Propeller for Attitude Control in Micro Air Vehicles"

Paper is not free but video conveys the idea well: https://www.youtube.com/watch?v=KZe7l5_LfoA

Likely with clever two-material molding you could do away with the hinge and it would look similar to the prototype shown in the article.

Re: Cleo Robotics Demonstrates Uniquely Clever Ducted Fan Drone

#13

Post by mannykannot »

hedgehog wrote: post #11
sterlind wrote: post #4

Perhaps the attitude of each fan blade rotates independently. To angle the drone, say, forwards, the fan blades might angle flat when they're at the forward position, every cycle, and angle tilted at the backwards position? Seems expensive and tricky though.

"An Underactuated Propeller for Attitude Control in Micro Air Vehicles" Paper is not free but video conveys the idea well: https://www.youtube.com/watch?v=KZe7l5_LfoA Likely with clever two-material molding you could do away with the hinge and it would look similar to the prototype shown in the article.

That is very clever, but the article says that this drone "introduce[s] control surfaces into the airstream to change the direction of the airflow and create a thrust vectoring effect." My guess is tiny spoilers around the inside of the duct to cause separation of the flow in one quadrant of the duct, allowing the Coanda effect to draw the stream in the opposite direction.

Re: Cleo Robotics Demonstrates Uniquely Clever Ducted Fan Drone

#19

Post by paulclinger »

hedgehog wrote: post #11
sterlind wrote: post #4

Perhaps the attitude of each fan blade rotates independently. To angle the drone, say, forwards, the fan blades might angle flat when they're at the forward position, every cycle, and angle tilted at the backwards position? Seems expensive and tricky though.

"An Underactuated Propeller for Attitude Control in Micro Air Vehicles" Paper is not free but video conveys the idea well: https://www.youtube.com/watch?v=KZe7l5_LfoA Likely with clever two-material molding you could do away with the hinge and it would look similar to the prototype shown in the article.

For those interested in details, the papers are linked from the project page: http://www.modlabupenn.org/2014/10/23/underactuated-rotor/.

> The main motor directly drives the propeller hub, which is itself connected to the propeller blades by two inclined hinges. The hinge geometry couples blade lead-and-lag oscillations to a change in blade pitch. Instead of only driving the motor with a steady torque, we add a sinusoidal component in phase with the rotation of the rotor to induce a cyclic pitch variation. The amplitude and phase of this control signal determines the magnitude and direction of the vehicle response.

Re: Cleo Robotics Demonstrates Uniquely Clever Ducted Fan Drone

#20

Post by madengr »

sterlind wrote: post #4

Perhaps the attitude of each fan blade rotates independently. To angle the drone, say, forwards, the fan blades might angle flat when they're at the forward position, every cycle, and angle tilted at the backwards position? Seems expensive and tricky though.

Yep, that’s how helicopters work, using a swash plate to change the rotor pitch every revolution.
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