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Cheapest variable pitch done supporting autorotation landings upon powerloss instead of falling dead when no power?

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Cheapest variable pitch done supporting autorotation landings upon powerloss instead of falling dead when no power?
The BEMF from the wind blowing on the electric motors (which are the same as turbine generators) could power whatever emergency processor handles autorotation, or a separate battery/capacitor could.
This would be for if the main battery connection fails, or is shorted out, or overheats, or unexpected EM interference combined with sudden weather changes and crappy RTH-on-signal-loss AI prevent RTH.
 
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Not sure I understand. Are you asking what drone has auto rotation capability? That's an easy answer. None. The props are too small to maintain motion long enough to land. Not enough inertia. And the Back EMF would be what kills you, not what saves you. It would stall the props quickly, and there's just not enough prop to slow the descent by any useful amount.

On the bright side, the Inspire 2 has dual batteries, which reduces the risk of complete power loss.

Interesting idea about the capacitors. You could in theory program the drone to use them to maintain attitude during the fall, and then use a burst of power close to the ground to facilitate a softer landing. I wonder if the weight penalty would be worth it?

And of course as you mentioned, you'd need variable pitch to make autorotation work. But the problem will any existing drone design is that there's just not enough prop to make it work.
 
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Not sure I understand. Are you asking what drone has auto rotation capability? That's an easy answer. None. The props are too small to maintain motion long enough to land. Not enough inertia. And the Back EMF would be what kills you, not what saves you. It would stall the props quickly, and there's just not enough prop to slow the descent by any useful amount.

On the bright side, the Inspire 2 has dual batteries, which reduces the risk of complete power loss.

Interesting idea about the capacitors. You could in theory program the drone to use them to maintain attitude during the fall, and then use a burst of power close to the ground to facilitate a softer landing. I wonder if the weight penalty would be worth it?

And of course as you mentioned, you'd need variable pitch to make autorotation work. But the problem will any existing drone design is that there's just not enough prop to make it work.
Large prop: four are only needed because of lack of variable pitch. Why not one large prop instead? Or two large ones on top of eachother (coaxial like the blackshark)?

Aux power: A decade ago, hobbyists put hydrogen fuel cells into the MATRICE 100. Why not use graphene supercapacitors? Better kwh/kg ratio than gasoline probably...
It is not like the new smart batteries are much cheaper, anyways.
 
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Large prop: four are only needed because of lack of variable pitch. Why not one large prop instead?
You're describing a helicopter, which absolutely exists in the model aviation world.



Or two large ones on top of eachother (coaxial like the blackshark)?
Those exist, too. I've seen model Chinooks.




Aux power: A decade ago, hobbyists put hydrogen fuel cells into the MATRICE 100. Why not use graphene supercapacitors?
It's maddening that that technology hasn't been more developed yet. I think there are agendas involved.

D
 
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What I HAVE seen is if you rotate your quad fast enough, you can lose up to two props and still land. There was a video of this on the Internet somewhere but I can't seem to find it.

D
 
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You're describing a helicopter, which absolutely exists in the model aviation world.




Those exist, too. I've seen model Chinooks.





It's maddening that that technology hasn't been more developed yet. I think there are agendas involved.

D
Wow, and it is functional? It will glide down upon powerloss? And it has the efficiency and quiet of constant speed rotors? It's not just a 3d printed Chinook shell on a crappy conventional drone platform?
 
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i’m all for thinking outside the box and coming up with new better ways to do things, however, I think the added complexity of a variable pitch system would actually increase the likelihood of a crash not decrease. Our crappy conventional drones are extremely reliable and require almost no maintenance because they are dirt simple mechanically. I doubt the same could be said for an RC helicopter with auto rotation capability.

If falling out of the sky is a significant fear for you there are parachute solutions that would work in a wider variety of emergency conditions and not add to the complexity of the of the overall system
 
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Cheapest variable pitch done supporting autorotation landings upon powerloss instead of falling dead when no power?
The BEMF from the wind blowing on the electric motors (which are the same as turbine generators) could power whatever emergency processor handles autorotation, or a separate battery/capacitor could.
This would be for if the main battery connection fails, or is shorted out, or overheats, or unexpected EM interference combined with sudden weather changes and crappy RTH-on-signal-loss AI prevent RTH.
Agree, you're describing a Heli... although even with a collective pitch rotor mast, I haven't seen a smaller "common" RC size Heli have an auto-rotation clutch in the drive train. It will spin down, easily seen when you land... takes a minute or two to stop main rotor after powering off... but still has friction on the main shaft.

To autorotate requires altitude, rotor inertia... and a Pilot that pitches rotors to greatly increase mast speed and when near contact flairs the rotors to create lift & slow craft. If performed too early, the rotors loose inertial & speed and she drops out of the sky.

So to truly auto-rotate the craft would need to be higher than probably flying it, and RC Pilot would need to perform the auto-rotation procedure (2 parts: inertia & flair) which might be challenging since you wouldn't know your mast speed or probably flair incorrectly near ground. The fear of battery loss... normally when a Heli battery becomes low, the performance drops to the point that you're coming down under dying battery.

To make this an "electronic package" automating the process would add additional weight. Unless you're suggesting having a backup battery to spin the rotor... a good low voltage "toner" connected to battery warns of low battery.

There are probably talented RC Heli Pilots, 3D flyers that may perform this... it's well beyond my skill set. Just flying a Heli... even the new GPS models is much more challenging than a stable drone.

The benefit of quad is stability and simplistic control that's led to impressive payloads. Until recently, there hasn't been much improvement in Heli's... they're no where near as stable as GPS Drone.

Heli's were long ahead of Drones... and built on a heli frame, not even remotely similar to quads. Scale Heli's are beautiful, some so detailed are simply amazing.

Good luck on your engineering venture... it'd be breaking new ground on some components.
A good parachute system would probably be more reliable in the end.
 

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