Lightweight/Powerful Speaker for Drone? - Wildlife Use

[Bio101]

Hi Everyone,

I am a biologist working on a project that involves hazing (scaring) shorebirds temporarily for their own protection, and I am hoping this group could help out with a portion of this. I have a drone (a 3DR Solo) and am looking for a speaker I can attach to it to play various sounds such as predator calls or loud bangs to assist with hazing the birds. The speaker would need to be lightweight and compact with as powerful of sound as I can get. Sound quality is not much of an issue, but the speaker would also need to play the sounds off of a memory card or something similar as bluetooth wont work at the distances I'll be flying the drone. It would attach via a gopro type three-prong mount, but there are adapters easily available for other types - I probably couldnt get away with a jury-rigged attachment though if there is no mount.

Internet searches haven't turned up anything that fits this bill just yet. Curious if anyone has leads on something that may work? Any help is appreciated!

Thanks,
-Dan

 

[robwpdx]

If you can tolerate a narrow beam, you could look into using 2 ultrasonic speakers. They are set up like heterodyne. One has a fixed frequency and the other varies. Several companies make them, I think the original patent expired.

For instance you can get 90dB at 1 meter with 24Watts from https://ultrasonic-audio.com/acouspade-classic-technical-specification/

 

[Bio101]

Thank you! I'll look into that but I think the sound will have to be broadcast a bit wider. I should also mention the max payload for this drone is listed at 3.3lbs, though I'd prefer to go below that to avoid murdering the battery life.

 

[Keith_W]

Welcome to ASR!

I would suggest a horn. You might be able to get an air horn with a can of compressed air, but (1) it will not sound like a predator and (2) you will need to find some way to activate it.

The next best option is to DIY a flying horn. You would need to 3D print a horn, and scavenge parts from a loud bluetooth speaker like one of these. Those typically have very long battery life (30-40 hours) which you do not need and will cost you weight in batteries. Replace the batteries with something lighter. Pair it with a light and small Digital Audio Player like the discontinued iPod Shuffle.

 

[Doodski]

Could use one of those horns that people make noise with at soccer matches. They are incredibly loud and lightweight. Strap it onto a can of compressed air and voila. A plunger/solenoid assembly for a 12 V DC to 13.4 V DC is common in old Sony and other brand name car cassette players and it should have enough force for a can of air to be discharged. Or make a whistle. Predators often sorta whistle and that scares birds. The driver for a Sony plunger may need to be a super-beta transistor with very high hfe like 350 or 500+. That will reduce the amount of parts using the super-beta transistor and ensure enough current and voltage gets to that cassette deck plunger used for discharging the can of air.
Examples of plunger/solenoid assemblies in action.

 

[audiofooled]

How about a very loud buzzer?

Loud Buzzer Volume Tests

Three very loud buzzers tested for SPL and frequency. Our standard warble type compared with ultra loud buzzers.

gizmo-engineering.com

 

[McFly]

I suggest posting over at DIYaudio too

 

[JSmith]

am looking for a speaker I can attach to it

May be worth a look, even though it is for a different drone model;

DJI Mavic 2 Enterprise Speaker (Part 5)-4G-838F-IT

JSmith

 

[staticV3]

@Bio101
You could try contacting the folks that manage the Berkeley Pit in Montana.
They have tons of experience hazing birds, including with drones:

Montana Resources

Montana Resources

www.montanaresources.com

Edit: Huh, I might've misremembered. I could've sworn that there was a section in the video where the team went over their arsenal of hazing equipment and how they've started to incorporate drones as well.
May have been from another video.

Shouldn't have posted the video from memory, sorry.

Edit 2: Ah there we go:
https://youtu.be/7h-QrL7zThA
https://www.mtpr.org/montana-news/2...nons-hazing-birds-from-the-toxic-berkeley-pit
https://www.sltrib.com/news/nation-world/2018/11/18/mine-company-turns-high/


And here's the original video I remembered: https://youtu.be/qtlPTE-UmY4
If you'll only read/watch one thing, watch this.

 

[restorer-john]

Maybe a small MP3 player with an onboard class D amp running from the main drone battery supply playing Diana Krall into a small horn speaker would do the trick?

The birds may never come back though....

 

[Trell]

Maybe a small MP3 player with an onboard class D amp running from the main drone battery supply playing Diana Krall into a small horn speaker would do the trick?

The birds may never come back though....

If they don’t die from acute boredom first.

 

[JSmith]

The birds may never come back though....

... Stevie Nicks.

JSmith