Definitely not a new form factor, this has been around for donkeys. I've personally seen them for at least 20 years at various industry shows.
This is presumably a totally uncritical lazy press release copy paste. For goodness sake, NASA's Ingenuity is not exactly a secret and that's only the latest in a very long line of commercial coaxial UAS.
Looks like a perfectly nice coax, but exactly the same tradeoffs of much higher mechanical complexity for a slightly smaller operating footprint which make them less appealing for most use cases. The article completely glosses over the fact that most traditional X/+ designs fold for transport.
"The ones you can see over there," answered his master, "with the huge arms, some of which are very nearly two leagues long."
"Now look, your grace," said Sancho, "what you see over there aren't giants, but windmills, and what seems to be arms are just their sails, that go around in the wind and turn the millstone."
"Obviously," replied Don Quixote, "you don't know much about adventures."
> Stacking the two rotors generates more thrust per unit area
But that's not a thing, and that's also not how that works. Multicopter rotor design is incredibly subtle.
(Two basic ideas for quad copters are that they need to slowly move horizontally for maximum efficiency, and that the vertical stagger between front and rear pair of rotors matters a lot.)
At the end of the day, this design is exactly what it is: Looks like a bottle which might be nice for someone. And the whole general layout thing boils down to flight time, in its weight class, with a given payload weight. There's not much more to it.
It at least doubles the thrust per swept area area, probably more, due to the counter-rotation and that the second stage rotor experiences a higher airspeed.
This isn't a multicopter. It's a coaxial helicopter. The design parameter most similar to the distance between two rotors on a multicopter is the rotor diameter.
It's obviously going to be less maneuverable though relative to the thrust, due to the cyclic being on only one rotor.
Far less than double. Putting one rotor directly in the turbulent wash of another is nowhere near as efficient as two well-separated rotors, for a number of reasons. https://en.wikipedia.org/wiki/Contra-rotating_propellers gives an estimate of "between 6% and 16% more efficient than normal propellers".
Yes, I don't know why I wrote it, since it's obviously wrong. I assumed mentally that they'd put as much power into the second propeller as into the first and that it'd go into the airflow reasonably effectively, but you don't double the thrust by doing that, you presumably double the power in the airflow, so that its velocity velocity to sqrt(2) times what it was, so you get a momentum increase by sqrt(2) and since force is the derivative of momentum the thrust is increased by sqrt(2), and then you a thrust increase by sqrt(2), and maybe you also get those 6-16% you mention.
Is there a swashplate or something that I do not see, or is it as I assume, some kind of mechanism that allows cyclic to be controlled implicitly by motor speed? Edit: The patent apparently says they have a swashplate and cyclic control on the bottom rotor, so it's basically a model helicopter.
They can't patent the coaxial bit just by adding the 'on a UAV', so they patent their way of having the blades collapse.
> Ascent's Helius may make the quadrotor form obsolete
We didn’t kill all the horses when we invented cars, as always the world just gets more complex. Quadcopters have an edge on this in terms of agility so many use cases will still be served by quadcopters
Standard 4-engine copter is VERY simple hardware wise - 4x blades+engines attached directly to a frame, plus some orientation sensors stolen from a phone. And that's enough to maneuver in any direction with ease, with turning radius of zero. That's why the whole industry is booming
That's probably overly dismissive. Drone warfare in Ukraine is one specific usecase and has been dominated by different factors, notably signal jamming, single use and mass production. This configuration might have some sensible usecases that won't necessarily match.
This is presumably a totally uncritical lazy press release copy paste. For goodness sake, NASA's Ingenuity is not exactly a secret and that's only the latest in a very long line of commercial coaxial UAS.
Looks like a perfectly nice coax, but exactly the same tradeoffs of much higher mechanical complexity for a slightly smaller operating footprint which make them less appealing for most use cases. The article completely glosses over the fact that most traditional X/+ designs fold for transport.