5 ms·

No, but they follow ballistic trajectories and can ricochet. A laser is at least predictable, and given that most drones would fly above ground level for visib

No, but they follow ballistic trajectories and can ricochet. A laser is at least predictable, and given that most drones would fly above ground level for visibility, it would take a very unlucky reflection to injure someone on the ground. A bullet is going to come down somewhere.

hga 12y ago
And we're likely talking about fairly low angles, i.e. less than 45 degrees up from horizontal. Straight up is fairly safe because air resistance slows the bullet on its way down. Less than 45 degrees, it's going to come down hard a long distance away. Shotguns are another possible approach, but I'm pretty sure the shot size required would be big enough to cause harm to more than people's eyes. And for this sort of thing civilian shotguns would have an effective range of maybe 50 yards max, so it would be a CIWS. The US Navy is moving from the 20mm Vulcan Gatling gun based Phalanx to a missile based CIWS ... that might be the most discriminating system after a laser, but still very problematic, you would have issues with the operators being very hesitant to set them to firing because there would likely be civilian casualties, and if it just turned out to be a paparazzi or otherwise non-dangerous drone, they'd get crucified.... And neither an effective laser nor an effective kinetic/explosive CIWS would be cheap.
TeMPOraL 12y ago
I didn't do the math here, but my intuition tells me that as lasers scatter, if you point a 1MW beam at a rough surface, you'll have a lot of high-power reflections in every direction - even a laser pointer reflecting off a wall is annoying for the eyes. I'd love someone more knowledgable about high-powered lasers to chime in here. Anyway, neither of those two options seem safe for drones flying just above people's heads. Maybe microwave lasers would be better? Also low-powered visible-light lasers could be enough to blind sensors and force the drone to rely on dead reckoning while not risking eye damage.

hga 12y ago

And we're likely talking about fairly low angles, i.e. less than 45 degrees up from horizontal. Straight up is fairly safe because air resistance slows the bullet on its way down. Less than 45 degrees, it's going to come down hard a long distance away. Shotguns are another possible approach, but I'm pretty sure the shot size required would be big enough to cause harm to more than people's eyes. And for this sort of thing civilian shotguns would have an effective range of maybe 50 yards max, so it would be a CIWS. The US Navy is moving from the 20mm Vulcan Gatling gun based Phalanx to a missile based CIWS ... that might be the most discriminating system after a laser, but still very problematic, you would have issues with the operators being very hesitant to set them to firing because there would likely be civilian casualties, and if it just turned out to be a paparazzi or otherwise non-dangerous drone, they'd get crucified.... And neither an effective laser nor an effective kinetic/explosive CIWS would be cheap.

TeMPOraL 12y ago

I didn't do the math here, but my intuition tells me that as lasers scatter, if you point a 1MW beam at a rough surface, you'll have a lot of high-power reflections in every direction - even a laser pointer reflecting off a wall is annoying for the eyes. I'd love someone more knowledgable about high-powered lasers to chime in here. Anyway, neither of those two options seem safe for drones flying just above people's heads. Maybe microwave lasers would be better? Also low-powered visible-light lasers could be enough to blind sensors and force the drone to rely on dead reckoning while not risking eye damage.