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When will these compact drones become less noisy? I know there are new propeller designs being researched to be much less like a swarm of bees is flying around

When will these compact drones become less noisy? I know there are new propeller designs being researched to be much less like a swarm of bees is flying around near you, but don't know how far off they are to retail commercialization. It just makes it hard to stomach flying a drone in a pristine environment knowing you are disturbing all human and non-human animals nearby.

FpUser 3y ago
Few deer I saw did not seem to care at all about the drone. Neither have raccoons, beavers, squirrels, chipmunks and birds.
- Ancapistani 3y ago
  Are you in a relatively urban area? In my experience, a wild deer can hear a photography quadcopter from ~200' away. They "spook" if I approach closer than ~150'.
  - FpUser 3y ago
    There is a farm I regularly pass on my bicycle and closer to the end of the summer they have boatload of deer coming in an wandering on the field. I have zero clue what they do on that field. Anyways those pay zero attention to my drone and go about their business whatever that is.
- jamies 3y ago
  Cool, yeah, just fly your drone next to wildlife and claim they don't mind.
  - jmspring 3y ago
    Living in a rural area with a lot of deer and other nature, they are one consideration.
- FpUser 3y ago
  Save the drama, they literally hang out in my backyard (well except beavers) but add foxes and rabbits
- blululu 3y ago
  This strikes me as a rather callous lack of empathy. Personally, I find the mosquito whine of drones to be really annoying - especially when I am trying to enjoy the peace and serenity of a natural environment. There is nothing more obnoxious than going surfing only to have some creep buzz you with a drone. It's really intrusive and the sound is plain just obnoxious. I'm trying to enjoy the ocean like people have done for eons and someone else can't seem to enjoy it without flying a high pitched squealing camera over my head? It's a shame too because as a camera enthusiast I would love to be able to take shots like the ones DJI features on its website. They are spectacular views. But the obtrusive rudeness of the technology is the one thing holding me back.
  - thinkmassive 3y ago
    I hear ya, but to your point about “some creep buzzing you,” at least you’re aware of it for now. A silent drone could be much creepier...
- tristanb 3y ago
  If i'm in nature and i hear a drone, its annoying AF, and it just makes me want to throw rocks at it.
  - FpUser 3y ago
    I hear loud music from drunk campers on the lakes way more often than I hear drones.
- bityard 3y ago
  Geese definitely do not like drones.
pwatsonwailes 3y ago
There's some interesting research around toroidal propellers which move the same amount of air, but create far less turbulence and so make a less annoying noise. However, they're not going to get significantly quieter until the energy density of the batteries gets significantly better (a lot of what you're moving with a drone is your energy storage). There's always a hope that someone might invent a really silent propellor, and there's some funky stuff you can do there with trailing edge profiles, but I don't think we'll see a huge leap beyond toroidals for a while.
- jcims 3y ago
  Zipline has built an interesting asymmetric design that's remarkably quiet. Mark Rober featured it in one of his recent videos. https://www.youtube.com/watch?v=DOWDNBu9DkU&t=831s https://www.youtube.com/watch?v=DOWDNBu9DkU&t=831s
  - pwatsonwailes 3y ago
    It does a similar sort of thing - asymmetric offset propellors shunt the frequency of what gets emitted way down. It still emits a similar amount of energy, but the direction of emission changes, and with the lower frequency, there's a lower perceived sound. Toroidal props actually have less sound coming off them, and at a lower frequency. I've got some ideas about how you'd potentially then have a greater spread of frequency by creating an offset toroidal, but I suspect the efficiency goes down, and I've got better things to do with my time than model sound profiles of weird, hard to manufacture (other than printing) prop geometries. Related note - the offset bit is similar to how car tyres work by having patterns in the tyre which spread the frequency response generated by each, so they don't have a multiplicative effect. (I can get really boring on applications of acoustic design but I'll cut off there)
    - robotguy 3y ago
      >I can get really boring on applications of acoustic design I found that fascinating. TIL about the car tire noise. I think you've got the right kind of audience here.
0_____0 3y ago
To some degree it's inescapable with the small props. The higher end DJI models have enormous props which are better for noise as well as endurance. 16" props on the Inspire 3. The natural extent of this progression is to have one or two very large 2-4 blade rotor (for low disc loading, high endurance, lower rotor speed and noise), with a small auxiliary rotor for yaw control if only using one lift rotor. Yes, the natural endpoint is in fact just a helicopter. Only reason we don't see more of that (edit: in photo drones specifically) is the mechanical complexity.
- Ancapistani 3y ago
  I've not actually measured the volume of various props - I can, and should! - but based on my memory I don't think it's quite as simple as "smaller props make more noise". For FPV stuff, I've flown everything from 25mm to 9" (prop size). The ones that seemed quietest were 2.5"-3", very light, and designed for performance. I think it has to do with the pitch of the noise and the "idle point" of your motors. Smaller props turn faster, and the faster they're turning the higher the pitch of the noise they produce. At some point it borders on inaudible. Even if it's technically producing more decibels (It might be! I've not tested that.), it isn't as disruptive. Larger props turn slower, producing less noise and at a lower pitch. "Idle point" is what I'm calling how much throttle you have to give it to hover. For my favorite 5" freestyle FPV quad, that's 18% (+/- 2% depending on temperature and humidity). It's acceptably quiet if I'm just hovering or slowly moving around, but sounds like an angry weedeater if I'm flying aggressively. The idle point for my 2.5"-3" quads is probably around 25%; my 7" long range build is 12%. The more throttle you give it, the faster the props spin, the louder and higher pitched it is.
jml7c5 3y ago
Zipline is using a rather strange propeller design that is apparently effective: https://www.youtube.com/watch?v=DOWDNBu9DkU&t=831s https://www.youtube.com/watch?v=DOWDNBu9DkU&t=831s
- 404mm 3y ago
  I saw that! I’m sure they will patent it and consumers will be stuck with more traditional designs. Sigh, the patent law really needs a refresh, considering how rapid research and market response became.
  - is_true 3y ago
    Do patents work when competing with a chinese company?
    - 404mm 3y ago
      Lol! I suppose they work if that Chinese company wants to sell in the US.
imiric 3y ago
Exactly. All this focus on improved image quality, battery life and whatnot, but no mention about noise levels, or even R&D into the area. Currently, only the video is usable from drone footage, which is a huge limitation. All drone footage either has music or an audio track from an external source overlaid on top of it. I wonder if the propeller and wind noise could be cancelled or removed with some fancy algorithms. It wouldn't eliminate the produced noise, but it would at least make the audio track usable.
- pphysch 3y ago
  > Currently, only the video is usable from drone footage, which is a huge limitation. For what use cases? Outdoor concerts? The acoustics at 100ft in the air are unlikely to be great anyways. I wouldn't call it a huge limitation.
  - dron57 3y ago
    I just want to watch Ukranian drone videos with glorious full sound Russian explosions without the annoying Ukranian techno.
    - brokenmachine 3y ago
      K2 Battalion has some great videos with foley sounds done very well...
  - Ancapistani 3y ago
    I've used on-board audio a few times, but it's rough. The only case that comes to mind where it was really successful IMO is if you're using an FPV quad to chase a vehicle: race cars, dirt bikes, monster trucks, etc. All of those things are loud enough that they're clearly audible over the prop and wind noise. If anything, for dynamic chase footage, the sound of the quad's motors spinning up adds interest. Otherwise, you're not going to hear anything worthwhile from the air.
  - deleted 3y ago
    [deleted]
ChancyChance 3y ago
Are they really that noisy? I fly 10" drones and once they are about 30 ft away you can't really hear them. 3" and 5" drones are silent at 30ft on a calm day.
- deleted 3y ago
  [deleted]

FpUser 3y ago

Few deer I saw did not seem to care at all about the drone. Neither have raccoons, beavers, squirrels, chipmunks and birds.

Ancapistani 3y ago
Are you in a relatively urban area? In my experience, a wild deer can hear a photography quadcopter from ~200' away. They "spook" if I approach closer than ~150'.
- FpUser 3y ago
  There is a farm I regularly pass on my bicycle and closer to the end of the summer they have boatload of deer coming in an wandering on the field. I have zero clue what they do on that field. Anyways those pay zero attention to my drone and go about their business whatever that is.
jamies 3y ago
Cool, yeah, just fly your drone next to wildlife and claim they don't mind.
- jmspring 3y ago
  Living in a rural area with a lot of deer and other nature, they are one consideration.
FpUser 3y ago
Save the drama, they literally hang out in my backyard (well except beavers) but add foxes and rabbits
blululu 3y ago
This strikes me as a rather callous lack of empathy. Personally, I find the mosquito whine of drones to be really annoying - especially when I am trying to enjoy the peace and serenity of a natural environment. There is nothing more obnoxious than going surfing only to have some creep buzz you with a drone. It's really intrusive and the sound is plain just obnoxious. I'm trying to enjoy the ocean like people have done for eons and someone else can't seem to enjoy it without flying a high pitched squealing camera over my head? It's a shame too because as a camera enthusiast I would love to be able to take shots like the ones DJI features on its website. They are spectacular views. But the obtrusive rudeness of the technology is the one thing holding me back.
- thinkmassive 3y ago
  I hear ya, but to your point about “some creep buzzing you,” at least you’re aware of it for now. A silent drone could be much creepier...
tristanb 3y ago
If i'm in nature and i hear a drone, its annoying AF, and it just makes me want to throw rocks at it.
- FpUser 3y ago
  I hear loud music from drunk campers on the lakes way more often than I hear drones.
bityard 3y ago
Geese definitely do not like drones.

pwatsonwailes 3y ago

There's some interesting research around toroidal propellers which move the same amount of air, but create far less turbulence and so make a less annoying noise. However, they're not going to get significantly quieter until the energy density of the batteries gets significantly better (a lot of what you're moving with a drone is your energy storage). There's always a hope that someone might invent a really silent propellor, and there's some funky stuff you can do there with trailing edge profiles, but I don't think we'll see a huge leap beyond toroidals for a while.

jcims 3y ago
Zipline has built an interesting asymmetric design that's remarkably quiet. Mark Rober featured it in one of his recent videos. https://www.youtube.com/watch?v=DOWDNBu9DkU&t=831s https://www.youtube.com/watch?v=DOWDNBu9DkU&t=831s
- pwatsonwailes 3y ago
  It does a similar sort of thing - asymmetric offset propellors shunt the frequency of what gets emitted way down. It still emits a similar amount of energy, but the direction of emission changes, and with the lower frequency, there's a lower perceived sound. Toroidal props actually have less sound coming off them, and at a lower frequency. I've got some ideas about how you'd potentially then have a greater spread of frequency by creating an offset toroidal, but I suspect the efficiency goes down, and I've got better things to do with my time than model sound profiles of weird, hard to manufacture (other than printing) prop geometries. Related note - the offset bit is similar to how car tyres work by having patterns in the tyre which spread the frequency response generated by each, so they don't have a multiplicative effect. (I can get really boring on applications of acoustic design but I'll cut off there)
  - robotguy 3y ago
    >I can get really boring on applications of acoustic design I found that fascinating. TIL about the car tire noise. I think you've got the right kind of audience here.

0_____0 3y ago

To some degree it's inescapable with the small props. The higher end DJI models have enormous props which are better for noise as well as endurance. 16" props on the Inspire 3. The natural extent of this progression is to have one or two very large 2-4 blade rotor (for low disc loading, high endurance, lower rotor speed and noise), with a small auxiliary rotor for yaw control if only using one lift rotor. Yes, the natural endpoint is in fact just a helicopter. Only reason we don't see more of that (edit: in photo drones specifically) is the mechanical complexity.

Ancapistani 3y ago
I've not actually measured the volume of various props - I can, and should! - but based on my memory I don't think it's quite as simple as "smaller props make more noise". For FPV stuff, I've flown everything from 25mm to 9" (prop size). The ones that seemed quietest were 2.5"-3", very light, and designed for performance. I think it has to do with the pitch of the noise and the "idle point" of your motors. Smaller props turn faster, and the faster they're turning the higher the pitch of the noise they produce. At some point it borders on inaudible. Even if it's technically producing more decibels (It might be! I've not tested that.), it isn't as disruptive. Larger props turn slower, producing less noise and at a lower pitch. "Idle point" is what I'm calling how much throttle you have to give it to hover. For my favorite 5" freestyle FPV quad, that's 18% (+/- 2% depending on temperature and humidity). It's acceptably quiet if I'm just hovering or slowly moving around, but sounds like an angry weedeater if I'm flying aggressively. The idle point for my 2.5"-3" quads is probably around 25%; my 7" long range build is 12%. The more throttle you give it, the faster the props spin, the louder and higher pitched it is.

jml7c5 3y ago

Zipline is using a rather strange propeller design that is apparently effective: https://www.youtube.com/watch?v=DOWDNBu9DkU&t=831s https://www.youtube.com/watch?v=DOWDNBu9DkU&t=831s

404mm 3y ago
I saw that! I’m sure they will patent it and consumers will be stuck with more traditional designs. Sigh, the patent law really needs a refresh, considering how rapid research and market response became.
- is_true 3y ago
  Do patents work when competing with a chinese company?
  - 404mm 3y ago
    Lol! I suppose they work if that Chinese company wants to sell in the US.

imiric 3y ago

Exactly. All this focus on improved image quality, battery life and whatnot, but no mention about noise levels, or even R&D into the area. Currently, only the video is usable from drone footage, which is a huge limitation. All drone footage either has music or an audio track from an external source overlaid on top of it. I wonder if the propeller and wind noise could be cancelled or removed with some fancy algorithms. It wouldn't eliminate the produced noise, but it would at least make the audio track usable.

pphysch 3y ago
> Currently, only the video is usable from drone footage, which is a huge limitation. For what use cases? Outdoor concerts? The acoustics at 100ft in the air are unlikely to be great anyways. I wouldn't call it a huge limitation.
- dron57 3y ago
  I just want to watch Ukranian drone videos with glorious full sound Russian explosions without the annoying Ukranian techno.
  - brokenmachine 3y ago
    K2 Battalion has some great videos with foley sounds done very well...
- Ancapistani 3y ago
  I've used on-board audio a few times, but it's rough. The only case that comes to mind where it was really successful IMO is if you're using an FPV quad to chase a vehicle: race cars, dirt bikes, monster trucks, etc. All of those things are loud enough that they're clearly audible over the prop and wind noise. If anything, for dynamic chase footage, the sound of the quad's motors spinning up adds interest. Otherwise, you're not going to hear anything worthwhile from the air.
- deleted 3y ago
  [deleted]

ChancyChance 3y ago

Are they really that noisy? I fly 10" drones and once they are about 30 ft away you can't really hear them. 3" and 5" drones are silent at 30ft on a calm day.

deleted 3y ago
[deleted]