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

arstechnica.com

41–49 of 49 posts

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

#41
post #29

Earlier quoted context omitted.

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

Why do you think a shaped charge is the correct ordinance type in this hypothetical?

I think it could better penetrate the skull.

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

#43
post #29

Earlier quoted context omitted.

> 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.

Not the slaughterbots bullshit again. If someone wanted to replicate the slaughterbots video, they would use the small drones only for face recognition to find the target and then eliminate the target with a small mortar from a bigger drone above. You know, the boring stuff that terrorists have already done in the past.

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

#44
post #36

> is able to generate a milliwatt of power that turns its propeller at over 15,000 rpm. How do you every do 15k rpm on 1 milliwatt? This sounds very odd to me, because unless You're in vacuum this is going to be a lot of air resistance..

By being very small. 15k rpm is 250 hertz. This is slightly lower than the lower bound wing frequency of a female mosquito, which can hover using approximately 100 μW - a tenth the power of this drone.

Citations: https://humbug.ox.ac.uk/sound https://pubs.aip.org/aip/pof/article-abstract/36/2/021907/32... https://www.dupagehealth.org/DocumentCenter/View/147/10-Thin...

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

#45
post #32

Earlier quoted context omitted.

> 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.

A/B test or not, 9mg is impossible. That would be half the mass on a grain of salt. At those length scales the interesting forces at play are not fluid mechanics, but capillary forces and surface tension. It also trivially easy to make - just rip a piece of gold foil weighing 9mg

A mosquito weighs 2.5 milligrams. It also has almost exactly the same hovering power to weight ratio. At 8mm high it is indeed a very tiny "drone", and exceedingly fragile, but it is certainly not impossible.

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

#46

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…

As others have said, it isn't a delivery platform. It'd do much better as a geostatic surveillance web, radio jammer, fire support, etc. Things that drones already do but set-and-forget.

Except that this one only hovers, so is wind-borne in terms of trajectory. It's a while away from being as useful as a real drone.

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

#47
post #29

Earlier quoted context omitted.

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

Not the slaughterbots bullshit again. If someone wanted to replicate the slaughterbots video, they would use the small drones only for face recognition to find the target and then eliminate the target with a small mortar from a bigger drone above. You know, the boring stuff that terrorists have already done in the past.

The rudimentary stuff terrorists are stuck with doing. Slaughterbots are more terrifying because they can track you in all the enviroments a mortar can't reach.

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

#48

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'…

The gas ganisters would be too heavy. A better payload is razor blades / needles coated in some potent venom poison, like tetrodotoxin ricin or cone snail toxins. Launch 1000 of these drones and you can kill an army in no time.
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