4 ms·

Heh, that's cute. The issue with that is that locating UAV's that are, say 50 meters above the deck, more than 1km from your detector is essentially impossible.

Heh, that's cute. The issue with that is that locating UAV's that are, say 50 meters above the deck, more than 1km from your detector is essentially impossible. Without a VERY dense detection infrastructure, catching these things is not going to happen. Furthermore even though these lasers are very cheap, by army norms, to fire, they're still 600$ or so for a single shot. So shooting down drones will be expensive. Far more expensive than the drones themselves. Third. Defense against a laser is easy (a mirror, essentially, though you need to know the frequency to get an effective one). I must say that I don't know why you'd try to defend a drone. I'd try to hide it, since that's so easy. And while a rules-based autopilot is easy to disrupt using jamming, a learned autopilot is essentially impossible to fool into crashing. Maybe you can divert it, I guess.

beagle3 8y ago
> Without a VERY dense detection infrastructure, catching these things is not going to happen. Not really, Where it matters, radars have been deployed that can easily find those things. I've seen live demonstrations in the mid 1980s (as in, a system protecting borders), and I bet the state of the art has advanced since then. IIRC it was a SAR system, but I'm not sure. > Furthermore even though these lasers are very cheap, by army norms, to fire, they're still 600$ or so for a single shot. So shooting down drones will be expensive. Far more expensive than the drones themselves. There are newer, weaker versions that are at ~$1/shot, that would still likely take down your average drone. Also, even $600 is not "far more" expensive than a modern drone that can carry things across the border; It is slightly more expensive, but (relatively speaking), super cheap and, since it is energy, fungible (that is, you don't spend it until you spend it, unlike e.g. missiles which have to be ready long beforehand) > Defense against a laser is easy (a mirror, essentially, though you need to know the frequency to get an effective one). I must say that I don't know why you'd try to defend a drone. I'd try to hide it, since that's so easy. That's the popular belief, but it is not actually true. A perfect mirror such as would be required would cost today significantly more than the drone itself, as in x10 to x100, if it is at all feasible (You can't have sharp edges, you likely need glass). It is currently infeasible to mirror-cover missiles or rockets that cost a lot more than the drone, and the problems are (mostly) not about the projectile speed or heat. > And while a rules-based autopilot is easy to disrupt using jamming, a learned autopilot is essentially impossible to fool into crashing. Maybe you can divert it, I guess. Lasers can blind cameras even better than they do human eyes. What sensors is this autopilot going to depend on when it is vision and GPS blinded?
- woodman 8y ago
  > I've seen live demonstrations in the mid 1980s (as in, a system protecting borders), and I bet the state of the art has advanced since then. Yup, long stare SAR hooked up to a DVR was a thing over 10 years ago - it could cover a lot of ground (like a large Iraqi city) with a resolution that would easily detect this drone.
  - candiodari 8y ago
    Are these the overhead not-quite-satellites you're talking about ? That would require a drone every 5 km or so. Not - one drone. A drone in the air 24/7 every 5km for a border ~2000 km long.
    - beagle3 8y ago
      The system I saw 30 years ago were more ground based and covered tens to hundreds of KMs. But even if you need a drone every 5km (you don't). That's all of 400 drones, 800 if you want to have pairs doing charge-work duty. For an 2000km border guarding operation, that's really not much. An order of magnitude or two cheaper than the fence they would guard.
      - candiodari 8y ago
        How did that ground based system solve the horizon problem ? Drones don't fly very high, so you'd need one of these systems, say at 50 meters drone height, ~ every 50km. That's probably worse than those drones watching from above, seeing as you'd need actual infrastructure at every interval. And, that'd be fixed infrastructure, with fixed blind spots.
        beagle3 8y ago
        I don't know exactly how it worked (beyond IIRC that it was a SAR = Synthetic Aperature Radar), but I know for sure that it worked perfectly well.
    - 8y ago
MikkoFinell 8y ago
> Furthermore even though these lasers are very cheap, by army norms, to fire, they're still 600$ or so for a single shot. So shooting down drones will be expensive. Far more expensive than the drones themselves. What is the approximate cost of allowing the drone in?
- zdkl 8y ago
  Depends if we assume they're smuggling or dropping explosives/something dirty.
  - MikkoFinell 8y ago
    Suppose they are smuggling narcotics.
    - candiodari 8y ago
      Okay, since economics has extensively studied the effect of narcotics on the economy (which is positive, or to put it another way: people will work, even fight, for drugs), we can clearly establish that the cost of missing a shipment is negative. For the economy, it is actually better to miss the shipment than to catch it.
      - MikkoFinell 8y ago
        So allowing Mexican cartels to smuggle and sell, for example, heroin has a positive economic effect on society? I have to admit that's a fresh perspective.
        candiodari 8y ago
        But you neglect to take into account the perspective I mentioned. Heroin certainly makes money go round and therefore helps GDP. We just, as a society, have decided that the social cost is not worth it.
aphextron 8y ago
>Furthermore even though these lasers are very cheap, by army norms, to fire, they're still 600$ or so for a single shot. So shooting down drones will be expensive. Far more expensive than the drones themselves. Where are you getting that $600 number? The laser in the article quoted is 150kW, which firing for a fraction of a second would be no more than a few dollars electricity.

beagle3 8y ago

> Without a VERY dense detection infrastructure, catching these things is not going to happen. Not really, Where it matters, radars have been deployed that can easily find those things. I've seen live demonstrations in the mid 1980s (as in, a system protecting borders), and I bet the state of the art has advanced since then. IIRC it was a SAR system, but I'm not sure. > Furthermore even though these lasers are very cheap, by army norms, to fire, they're still 600$ or so for a single shot. So shooting down drones will be expensive. Far more expensive than the drones themselves. There are newer, weaker versions that are at ~$1/shot, that would still likely take down your average drone. Also, even $600 is not "far more" expensive than a modern drone that can carry things across the border; It is slightly more expensive, but (relatively speaking), super cheap and, since it is energy, fungible (that is, you don't spend it until you spend it, unlike e.g. missiles which have to be ready long beforehand) > Defense against a laser is easy (a mirror, essentially, though you need to know the frequency to get an effective one). I must say that I don't know why you'd try to defend a drone. I'd try to hide it, since that's so easy. That's the popular belief, but it is not actually true. A perfect mirror such as would be required would cost today significantly more than the drone itself, as in x10 to x100, if it is at all feasible (You can't have sharp edges, you likely need glass). It is currently infeasible to mirror-cover missiles or rockets that cost a lot more than the drone, and the problems are (mostly) not about the projectile speed or heat. > And while a rules-based autopilot is easy to disrupt using jamming, a learned autopilot is essentially impossible to fool into crashing. Maybe you can divert it, I guess. Lasers can blind cameras even better than they do human eyes. What sensors is this autopilot going to depend on when it is vision and GPS blinded?

woodman 8y ago
> I've seen live demonstrations in the mid 1980s (as in, a system protecting borders), and I bet the state of the art has advanced since then. Yup, long stare SAR hooked up to a DVR was a thing over 10 years ago - it could cover a lot of ground (like a large Iraqi city) with a resolution that would easily detect this drone.
- candiodari 8y ago
  Are these the overhead not-quite-satellites you're talking about ? That would require a drone every 5 km or so. Not - one drone. A drone in the air 24/7 every 5km for a border ~2000 km long.
  - beagle3 8y ago
    The system I saw 30 years ago were more ground based and covered tens to hundreds of KMs. But even if you need a drone every 5km (you don't). That's all of 400 drones, 800 if you want to have pairs doing charge-work duty. For an 2000km border guarding operation, that's really not much. An order of magnitude or two cheaper than the fence they would guard.
    - candiodari 8y ago
      How did that ground based system solve the horizon problem ? Drones don't fly very high, so you'd need one of these systems, say at 50 meters drone height, ~ every 50km. That's probably worse than those drones watching from above, seeing as you'd need actual infrastructure at every interval. And, that'd be fixed infrastructure, with fixed blind spots.
      - beagle3 8y ago
        I don't know exactly how it worked (beyond IIRC that it was a SAR = Synthetic Aperature Radar), but I know for sure that it worked perfectly well.
  - 8y ago

MikkoFinell 8y ago

zdkl 8y ago
Depends if we assume they're smuggling or dropping explosives/something dirty.
- MikkoFinell 8y ago
  Suppose they are smuggling narcotics.
  - candiodari 8y ago
    Okay, since economics has extensively studied the effect of narcotics on the economy (which is positive, or to put it another way: people will work, even fight, for drugs), we can clearly establish that the cost of missing a shipment is negative. For the economy, it is actually better to miss the shipment than to catch it.
    - MikkoFinell 8y ago
      So allowing Mexican cartels to smuggle and sell, for example, heroin has a positive economic effect on society? I have to admit that's a fresh perspective.
      - candiodari 8y ago
        But you neglect to take into account the perspective I mentioned. Heroin certainly makes money go round and therefore helps GDP. We just, as a society, have decided that the social cost is not worth it.

aphextron 8y ago

>Furthermore even though these lasers are very cheap, by army norms, to fire, they're still 600$ or so for a single shot. So shooting down drones will be expensive. Far more expensive than the drones themselves. Where are you getting that $600 number? The laser in the article quoted is 150kW, which firing for a fraction of a second would be no more than a few dollars electricity.