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> The tech required for search and rescue is the same tech required for search and destroy. Haha, no, no it's not. (I'm very active in SAR -- headed out to a l

> The tech required for search and rescue is the same tech required for search and destroy. Haha, no, no it's not. (I'm very active in SAR -- headed out to a large search this weekend, even.) We've had "search and destroy" for a decade now, but SAR still doesn't have effective use of drones. Quadcopters can navigate tricky terrain close enough to the ground to see a sufficient amount of detail, but they only get about 25 minutes of flight time. Fixed-wing drones can get much better flight time, but we can't put them anywhere near close enough to the ground to see the average missing person. Typically the next thing people suggest is IR. Yeah, IR's great, there's just one problem: there are a lot of IR sources on the ground, even in the wilderness, and people with clothing on aren't that great a source of IR by comparison. At a recent multi-agency training event, I reviewed footage from a repurposed Reaper drone flown by the national guard after the southern California mudslides. Making out the difference between a person on the ground and a streetlamp was impossible. The only documented drone find I've heard of so far was a person sitting in an orchard. Probably there have been others, but the point is: SAR is a wildly different situation than people imagine. There was just a study done by DJI and European agencies that found that drones were of negligible benefit in the missing person scenarios they tried: https://www.aopa.org/news-and-media/all-news/2018/october/01/drone-study-reveals-potential-and-limits https://www.aopa.org/news-and-media/all-news/2018/october/01... Helicopters and civil air patrol are superior to drones in almost every way. I've hung out the side of a UH-60 and a couple of Lakotas during exercises looking for brightly colored objects on the ground. At around 100 feet above ground level our success rate was around 60%. Heck, we had a missing small aircraft, in the snow, a year and a half ago. There were hundreds of searchers on the ground, multiple CAP and helo overhead. Guess who found it? Some folks on snowmobiles a few weeks later. We use a number called "POD" -- Probability of Detection -- in our reports after every assignment. It's an ass-pull guesstimate at what our odds were of locating a responsive subject, an unresponsive subject, or a clue during the assignment. High POD for a close grid search pattern on the ground in light forest for an unresponsive subject is about 70%. Average POD for an unresponsive subject by a fleet of quadcopters in the same environment would be like 5%. To effectively rule the area out, any decent search manager would deploy a ground team anyway. So, in the first place, this MIT experiment -- while very cool -- still suffers from a lot of the same issues that this technology has in a SAR context. And in the second place, shooting down efforts to develop this technology for civilian use is silly because, well, I hate to break it to ya, but we've been killing people with (mostly autonomous) drones for a while now. That horse is already outta the barn.

gaius 8y ago
looking for brightly colored objects on the ground. At around 100 feet above ground level our success rate was around 60%. I've done SAR at sea and it is frightening how close you can be to who/what you are looking for and not see them/it because of the waves, or reflections, or low cloud/fog, or rain, and then there's the constant movement of everything due to currents and wind, the inaccuracy of GPS and shooting resections... And you can't just have guys out looking, there are only a small number of RIBs or other assets, and they have limited endurance, and the sea is very very big. SAR is a hard, hard problem as you say. When I dive for fun now, I take an excessive amount of gear incase I ever need to be found.
stillsut 8y ago
How well would sound work? As in listening for the person to yell out to an autonomous vehicle flying above the canopy. Obviously drones are noisy, so maybe fixed wing. Or maybe you could have a microphone suspended on a cable fifty feet below a quad, with an apparatus that shields noise from above. But there seem to be promising characteristics too for this situation: 1.) human voice is very different than propeller hum, 2.) wildernesses have very minimal background noise. Filter and classify outliers. I say this as someone whose only SAR situation was getting himself out of the Vermont woods at dusk by hiking roughly a mile towards the sound of a barking dog.
- thaumaturgy 8y ago
  People have discussed that. A flying thing that could be used to relay instructions to lost parties would be helpful in a few situations. I think search organizations are certainly interested in UAVs, but at the moment nobody's sure how to use them effectively. It kinda strikes me as being like blockchain: cool technology, everybody wants to use it, but there aren't really that many real-world use cases where something else isn't just as good or better. Probably the highest priority should be fixing their flight time. 25 minutes is just not enough time in the air to be useful, and fixed-wing is too tricky to navigate in too many kinds of terrain. If someone figures out how to start approaching 60 minutes in the air with a payload -- speaker & microphone, IR, comms -- that would probably start getting more attention. Another thing that would be really cool is an airborne minicell. Just about everyone's carrying a smartphone now, they're just going into areas where there's no signal. If something could go out there offering signal, and report back when a device tries to connect to it, it wouldn't necessarily need to get close to the ground and that could really narrow down some of our searches.

gaius 8y ago

looking for brightly colored objects on the ground. At around 100 feet above ground level our success rate was around 60%. I've done SAR at sea and it is frightening how close you can be to who/what you are looking for and not see them/it because of the waves, or reflections, or low cloud/fog, or rain, and then there's the constant movement of everything due to currents and wind, the inaccuracy of GPS and shooting resections... And you can't just have guys out looking, there are only a small number of RIBs or other assets, and they have limited endurance, and the sea is very very big. SAR is a hard, hard problem as you say. When I dive for fun now, I take an excessive amount of gear incase I ever need to be found.

stillsut 8y ago

How well would sound work? As in listening for the person to yell out to an autonomous vehicle flying above the canopy. Obviously drones are noisy, so maybe fixed wing. Or maybe you could have a microphone suspended on a cable fifty feet below a quad, with an apparatus that shields noise from above. But there seem to be promising characteristics too for this situation: 1.) human voice is very different than propeller hum, 2.) wildernesses have very minimal background noise. Filter and classify outliers. I say this as someone whose only SAR situation was getting himself out of the Vermont woods at dusk by hiking roughly a mile towards the sound of a barking dog.

thaumaturgy 8y ago
People have discussed that. A flying thing that could be used to relay instructions to lost parties would be helpful in a few situations. I think search organizations are certainly interested in UAVs, but at the moment nobody's sure how to use them effectively. It kinda strikes me as being like blockchain: cool technology, everybody wants to use it, but there aren't really that many real-world use cases where something else isn't just as good or better. Probably the highest priority should be fixing their flight time. 25 minutes is just not enough time in the air to be useful, and fixed-wing is too tricky to navigate in too many kinds of terrain. If someone figures out how to start approaching 60 minutes in the air with a payload -- speaker & microphone, IR, comms -- that would probably start getting more attention. Another thing that would be really cool is an airborne minicell. Just about everyone's carrying a smartphone now, they're just going into areas where there's no signal. If something could go out there offering signal, and report back when a device tries to connect to it, it wouldn't necessarily need to get close to the ground and that could really narrow down some of our searches.