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Comment Was predicted in SF 20 years ago or so... (Score 1) 99

I remember that an SF story a couple of decades ago predicted that cruise missiles and the computer technology to direct their swarming would make them inexpensive weapons of choice for some nations. Looks as if that time is upon us.

"...officials note, having this capability will force adversaries to focus on UAV swarm response." I hope that we also have some focus onUAV swarm response; the 'swarm' of Kamikaze attacks on our fleet off Okinawa in WWII inflicted great damage even though we had AA shells with proximity fuzes, early warning radar, and fighter aircraft for interception.

Comment Re:Line Count is Misleading (Score 1) 23

I don't see that Mr | Ms | Mrs Coward's comment is pertinent. I sure don't want to need to code "y = z++" in assembly, much less binary, each time I need it. Computer languages are made up of symbols that translate to several to many lines of code and come with libraries of still more abstract code and the trend of higher abstraction appears to be continuing. It's good have routines coded once that that are used many times. Productivity increases.

Comment Re:A smart phone is rarely convenient (Score 1) 248

I agree with fff.

I suspect that the savings and utility will come with new construction where, for instance, the load carrying copper wires only go to the outlets or lights and the controls, which could control the light, socket, etc. could be wireless but their power would come a separate low voltage, low amperage, circuit this saving quite a bit of copper. The smartphone could control selected or all circuits but would not be the only control.

As an example thermostats control furnaces and air conditioners via low voltage, low amp, wires. New ones may also be controlled by a smartphone or computer.

It's probably not very cost efficient to convert existing homes in most cases.

BTW I get points when I mention that I can't go out as I need to update the firmware in my front door lock.

Comment Re:but... my face is smaller than 25 cm? (Score 1) 140

Only if you're looking up in the direction of the satellite, otherwise it's your head that would be about 1 pixel. Of course it's unlikely in either case that your your head/face would be contained in one pixel so it would more probably be split among 2 or 4 pixels.

Comment Re:GPS on Mars (Score 1) 104

GPS is just a stand-in for the system they would use on Mars, which would be a much simplified version using existing satellites and the transport vehicle for the lander itself.

The atmosphere in Mars is fine for a quadcopter if designed correctly. How do you think the parachutes on NASA landers work?

I'm not sure what you mean by "simpler" system, what would it be? AFAIK it takes signals from 4 GPS satellites to get a fix, I think that it could be done with 3 having knowledge of the approximate position. That's with 3 or 4 satellites with GPS electronics in view at once. This implies that there need to be several more than 3 satellites in the constellation to be certain of having 3 or 4 in the correct position at any time. I don't think that the orbits of multi purpose satellites would be the ones needed for GPS.

Parachutes are used to slow the descent rate of the landers and are then cut away as the descent rate is still pretty high. Other methods need to be used to bring the lander to touchdown. I guess some engineers experienced in origami might be able to design a multiple rotor copter that would be compact in transit yet unfold properly once the parachute slows the descent rate etc, etc, etc.

Comment Fixed a bug in flight (Score 1) 310

A couple of decades ago I was in a twin engine aircraft over the Amazon with some scientists who were collecting atmospheric data including distribution of smoke particle sizes, CO2, CO, humidity, temperature, Hg, etc. when it became apparent that some code I wrote wasn't working well with the interface on the aircraft (supposedly identical to the one in my lab). I was able to devise a fix on my (luggable) notebook, compile, link, and install it in flight and the rather bumpy mission continued. This was also been the only time in my life that a pilot has taxied an aircraft that I was on into the hanger at the end of the mission.

Comment Re:Not practical as contact lenses (Score 3, Interesting) 99

When I go out to the desert on a clear day I'm getting a lot of infrared, if it blocked out normal vision I wouldn't need sunglasses (except that the glasses block UV). Perhaps what was meant is that the lens that would be needed to focus the light would block the IR and the lens for IR would block visible light. That's generally true except for near IR (NIR) but to separate NIR from visible IR a filter to do that would be used just as it is used in digital cameras.

The article implies that it works across the IR spectrum but that's enormously wide - from about 700 nm to 1 mm wavelength with ever decreasing energy in the photons.

I think that there is less information in the press release than meets the eye.

Comment Re:Lat / Long? (Score 1) 461

That's already inexpensively available; it's called Automatic Flight Following (AFF). It's small, easily installed, and inexpensive to operate . Those that I am familiar with send a GPS position, including altitude, every 2 minutes via satellite to a ground station. I believe that track, not heading, and ground speed are calculated using the previous datum. The data are available for display on a digital aviation chart, map, Google Earth, etc. It's been available for many years. All of the US Federal fire fighting aircraft have them and that includes contractor's aircraft. I suspect that most US Federal aircraft have them no matter what their use.

The system that I've used will tag the last datum received if it has been more than 10 minutes since the last one and the icon on the display will be red. Probably the system could send alter text messages and emails, too. The display allows for viewing the last position of many aircraft or the track of a single one from an arbitrary time to the most recent datum.

This certainly helps discovery of a problem and provides a good starting point for SAR efforts.

Two is not equal to three, even for large values of two.