Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Researchers build a solar-powered hovering drone that weighs only 9 mg

arstechnica.com

Post reply on HN
Print view View original

21–30 of 49 posts

Re: Researchers build a solar-powered hovering drone that weighs only 9 mg

#21

Post by jessriedel »

throwup238 wrote: post #14

Every time I see one of these drone tech demonstrations, I can't help but wonder how they will be adapted for warfare. This one... I'm seeing flying solar powered landmines (skymines?) that can flutter around an active combat zone aimlessly for hours until it detects a personnel target and bops them near the temple with a small round. I wonder if there are any actual benefits over just putting a solar panel on a regu…

> and bops them near the temple with a small round.

The smallest commercially available centerfire cartridge was the 2.7mm Kolibri round, which was too underpowered to inflict significant damage to a person other than maybe if you hit them right in the eyeball. That round weighed 5.3 grams while the OP article talks about a drone weighing 9 milligrams.

https://en.wikipedia.org/wiki/2mm_Kolibri

This drone just doesn't have enough payload for explosives/bullets to be useful against a person. More plausible is some sort of biological attack, like a nerve gas, although you'd be pushing the limits even there. The LD50 for sarin gas is 1 milligram, and you would need a delivery mechanism.

Re: Researchers build a solar-powered hovering drone that weighs only 9 mg

#22

Post by GenerocUsername »

Jtsummers wrote: post #9
GenerocUsername wrote: post #8

Article says 4g title says 9mg

> However, the design can be miniaturized, and the researchers built a version that weighs only 9 milligrams. Ars A/B tests their titles so I don't know if the submitter editorialized or if they saw a different title than the rest of us, but the text of the article does include building a 9 mg version.

Interesting. Thanks for clarification

Re: Researchers build a solar-powered hovering drone that weighs only 9 mg

#23

Post by jxcole »

jessriedel wrote: post #21
throwup238 wrote: post #14

Every time I see one of these drone tech demonstrations, I can't help but wonder how they will be adapted for warfare. This one... I'm seeing flying solar powered landmines (skymines?) that can flutter around an active combat zone aimlessly for hours until it detects a personnel target and bops them near the temple with a small round. I wonder if there are any actual benefits over just putting a solar panel on a regu…

> and bops them near the temple with a small round. The smallest commercially available centerfire cartridge was the 2.7mm Kolibri round, which was too underpowered to inflict significant damage to a person other than maybe if you hit them right in the eyeball. That round weighed 5.3 grams while the OP article talks about a drone weighing 9 milli grams. https://en.wikipedia.org/wiki/2mm_Kolibri This drone just doesn'…

If you look carefully you see that they actually started with a much bigger drone and then shrunk it down. The minimum is 9 mg (that they could build) but it sounds like the design can be expanded to almost any size. A more obvious question would be is there any functional difference between this and a balloon.

Re: Researchers build a solar-powered hovering drone that weighs only 9 mg

#24

Post by gertlex »

jessriedel wrote: post #21
throwup238 wrote: post #14

Every time I see one of these drone tech demonstrations, I can't help but wonder how they will be adapted for warfare. This one... I'm seeing flying solar powered landmines (skymines?) that can flutter around an active combat zone aimlessly for hours until it detects a personnel target and bops them near the temple with a small round. I wonder if there are any actual benefits over just putting a solar panel on a regu…

> and bops them near the temple with a small round. The smallest commercially available centerfire cartridge was the 2.7mm Kolibri round, which was too underpowered to inflict significant damage to a person other than maybe if you hit them right in the eyeball. That round weighed 5.3 grams while the OP article talks about a drone weighing 9 milli grams. https://en.wikipedia.org/wiki/2mm_Kolibri This drone just doesn'…

Thanks for the insights on that half of the hypothetical! 9mg is indeed wild, and made me go check the article... The article is a bit confusing, or I'm missing some nuances. It seems to talk about 2-3 drones, I think, mentioning weights of: 9 mg, 1.13 g, and 4 g. I think the one in the video is not the 9 mg version.

Re: Researchers build a solar-powered hovering drone that weighs only 9 mg

#25

Post by throwup238 »

jessriedel wrote: post #21
throwup238 wrote: post #14

Every time I see one of these drone tech demonstrations, I can't help but wonder how they will be adapted for warfare. This one... I'm seeing flying solar powered landmines (skymines?) that can flutter around an active combat zone aimlessly for hours until it detects a personnel target and bops them near the temple with a small round. I wonder if there are any actual benefits over just putting a solar panel on a regu…

> and bops them near the temple with a small round. The smallest commercially available centerfire cartridge was the 2.7mm Kolibri round, which was too underpowered to inflict significant damage to a person other than maybe if you hit them right in the eyeball. That round weighed 5.3 grams while the OP article talks about a drone weighing 9 milli grams. https://en.wikipedia.org/wiki/2mm_Kolibri This drone just doesn'…

From TFA:

> The total system required just over half a watt of power to stay aloft. Given a total mass of 4 grams, that works out to a lift-to-power efficiency of 7.6 grams per watt. But a lot of that power is lost during the voltage conversion. If you focus on the motor alone, it only requires 0.14 watts, giving it a lift-to-power efficiency of over 30 grams per watt....

> But one thing they don't have to optimize is the vehicle's size since they already built a miniaturized version that's only 8 millimeters high and weighs just 9 milligrams but is able to generate a milliwatt of power that turns its propeller at over 15,000 rpm.

9mg is just the smallest version they managed to make. Based on the size of the solar panel in the video, there's plenty of room to scale to tens of grams per drone. And this is a laboratory proof of concept, not a well funded weapons prototype.

Re: Researchers build a solar-powered hovering drone that weighs only 9 mg

#27

Post by squarefoot »

I wonder how feasible would be adding an actuator that slightly tilts the propeller axis, driven according to the direction from which the drone is receiving sunlight, so that the drone would turn always to the sun, remaining airborne as long as it can follow its light.

Re: Researchers build a solar-powered hovering drone that weighs only 9 mg

#28

Post by denotational »

squarefoot wrote: post #27

I wonder how feasible would be adding an actuator that slightly tilts the propeller axis, driven according to the direction from which the drone is receiving sunlight, so that the drone would turn always to the sun, remaining airborne as long as it can follow its light.

I think you might be describing a (photosynthetic) moth!

Re: Researchers build a solar-powered hovering drone that weighs only 9 mg

#29

Post by pfdietz »

jessriedel wrote: post #21
throwup238 wrote: post #14

Every time I see one of these drone tech demonstrations, I can't help but wonder how they will be adapted for warfare. This one... I'm seeing flying solar powered landmines (skymines?) that can flutter around an active combat zone aimlessly for hours until it detects a personnel target and bops them near the temple with a small round. I wonder if there are any actual benefits over just putting a solar panel on a regu…

> and bops them near the temple with a small round. The smallest commercially available centerfire cartridge was the 2.7mm Kolibri round, which was too underpowered to inflict significant damage to a person other than maybe if you hit them right in the eyeball. That round weighed 5.3 grams while the OP article talks about a drone weighing 9 milli grams. https://en.wikipedia.org/wiki/2mm_Kolibri This drone just doesn'…

I suspect a 5.3 gram shaped charge detonated right near the head will do much more damage.

Re: Researchers build a solar-powered hovering drone that weighs only 9 mg

#30

Post by FredPret »

Every time war gets automated more or mil-tech improves, the value of information and information processing goes up, and so does the ability to mess with the enemy's information.

No point in having an ICBM unless you know where to point it and how to guide it there. No point in having a loitering kill-drone swarm if you can't keep it from getting hacked.

Post reply on HN