4 ms·
A New Form Factor for Drones: Vertical and Coaxial
- impossiblefork 2y agoThough, how do they control cyclic? 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.
- Zanfa 2y agoIf you look closely at the 6th picture in the article, the swashplate arms are visible on the bottom rotor.
- impossiblefork 2y agoAh, yes. I missed them at first.
- blutack 2y agoThey can't patent the coaxial helicopter UAV bit because there's a huge amount of prior art.
- impossiblefork 2y agoYes, that is basically the idea.
- jackhalford 2y ago> 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
- hengheng 2y ago> 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.
- impossiblefork 2y agoIt 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.
- raydiak 2y agoFar 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 https://en.wikipedia.org/wiki/Contra-rotating_propellers gives an estimate of "between 6% and 16% more efficient than normal propellers".
- impossiblefork 2y agoYes, 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.
- wao0uuno 2y agoHalf Life 2 predicted this more than 20 years ago. Next step is to make the rotors razor sharp.
- 05 2y agoJust use a 450 class heli instead.. https://www.rcgroups.com/forums/showthread.php?165680-Man-Killed-by-Model-Helicopter https://www.rcgroups.com/forums/showthread.php?165680-Man-Ki... https://www.rcgroups.com/forums/showthread.php?1991999-Heli-Kills-Man-in-NYC https://www.rcgroups.com/forums/showthread.php?1991999-Heli-...
- hashtag-til 2y agoI'm sure the community will make an inexpensive Pringles version of it.
- blutack 2y agoDefinitely 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.
- rasse 2y agoIt's not a new form factor for Ascent Aerosystems, either. They did a Kickstarter for a coaxial drone in 2017. https://www.kickstarter.com/projects/ascentaerosystems/sprite-the-portable-rugged-totally-different-small https://www.kickstarter.com/projects/ascentaerosystems/sprit...
- alphan0n 2y ago> this has been around for donkeys "What giants?" asked Sancho Panza. "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."
- blutack 2y agoContraction of donkey's years, a common en-GB idiom for a long time. Good reference though!
- d--b 2y agoI think the argument that the quad copter looks incredibly cooler than this flying turd is going to matter eventually.
- out_of_protocol 2y agoStandard 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
- IshKebab 2y agoWhy though? Seems way more complicated (swashplates!) for little benefit (a bit more compact?)
- dogman1050 2y agoIf it falls over while landing, it'll require manual righting. Flat drones don't have this risk.
- Fokamul 2y agoSorry but this is overpriced crap, maybe good for US army buying thousands of these, because someone knows someone in government. But if you really want to see proven drone designs, which are upgraded by war experience, just look at Ukraine drone units. That's it.
- meheleventyone 2y agoThat'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.
- dwighttk 2y agoUgh I hate those videos that each went to full screen and had to be closed for me to continue READING I don’t even want em to autoplay much less auto-full-screen
- bluesounddirect 2y agothere is something odd about that site . scroll it starts playing a video. scroll past another point it does it again . scammy !
- maxldn 2y agoI guess they decided that auto play video wasn’t _quite_ irritating enough