I recently visited some friends and colleagues at Wharton to discuss my work on evolution of flying. Naturally, Malaysia Air MH370 came up. We have continued the discussion by email since I got back. Here is a note I wrote, explaining why it’s impossible to preprogram a flight plan so that the pilots could not override it, if they were conscious.
Notice the automatic circling when it reached Athens. Everyone onboard was dead.
Sid, overriding manual override is designed to be impossible. The pilots always have override. Indeed, the first 2 items on some emergency procedures are:
1) Disengage autopilot
2) Disengage auto throttle
and there are specific buttons to make that easy to do in a hurry. (As well as by going into the Flight computer and reprogramming it, or rebooting it, etc. ) Continue reading →
The Telephone Wires of Manhattan, 1887. Switchboards were a big step forward. This picture also shows an advantage of living in a city: better communications. Still true today, except measured in milliseconds.
[edits Jan. 31] A poli sci friend recently blogged about the Ukranian government’s “text that changed the world,” a mass text message thousands of anti-government demonstrators in Kiev. She asked 1) How did the government know who was in the main square of Kiev that day? (Cell phone location) and 2) How did it send the same message to everyone at once? (Mass SMS)
Demonstrators in Kiev. From CNN
The second question is easy: phone companies routinely provide mass-SMS services to large customers. For example, I’m on the “emergency alert” texting service of UC San Diego’s campus police. It was designed for earthquakes, but it has been used for other kinds of messages “between earthquakes.” The same message goes out to every phone number on their list.
What to do to avoid tracking? Short version: Leave your phone at home. Second best is to shut it off or switch to airplane mode, but those work only if the government is not making an effort to target you.
An interesting question about how much latency is acceptable for UAV operation. http://lnkd.in/dx-BfVk My answer, based partly on my radio control flying experience, is that it depends heavily on the context. 200 milliseconds is too long for stunt flying, but not a problem for flying larger UAVs at higher altitudes. The operator has to “dial in” their reflexes to the situation, just as sailors do with different sizes of sailboats. Here’s an example where low latency is essential:
A seeming paradox is that longer latencies are acceptable only at higher Stages of Control. (See my draft book for discussion of this concept.) At the high end (what I call Computer Integrated Flying), if enough knowledge is embodied in the aircraft, the operator can pull back entirely from flying, and switch to “commanding” the aircraft.
Time to debunk another widely covered press story about wonderful new inventions coming from a tech giant. Ars Technica had one of many articles about Google’s “announcement” of a blood glucose sensor in a contact lens. The discussion after the article is good, as often happens with Ars. Here’s my quick explanation of why the concept will fail. Unfortunately.
Non-invasive glucose testing is the perennial “pot of gold at the end of the rainbow.” Google is not the first to try using tears; the others have failed, and they will too. They say it is “5 years away,” which is equivalent to saying “We have not yet tested it on real diabetics.”
The problem is basically that tears won’t track blood glucose levels closely. Tears are secreted by the lacrimal gland. I’ve never studied it, but the composition of its secretion is sure to depend on a multitude of variables. (Think: sweat, saliva, etc.) Even if a relationship exists and can be quantified “on average,” there will be lags.
It’s possible that a device like this could supplement other measurement systems. But nothing will be as good as actual blood measurements. Therefore finger sticks will always be needed for calibration. The best realistic case is that a contact lens device could serve as an early warning; but finger sticks will still be needed for validation before taking any action.
This review really missed the boat on both law and safety issues for drones. Some of what it discussed is illegal (unfortunately – I think the present law against commercial use of UAVs is too strong). A lot of it is unsafe, or rather it will be unsafe in the hands of newbies who buy this expensive but very-easy-to-use piece of technology. Review – The Phantom 2 Vision Photo Drone From DJI – NYTimes.com.
I’m not impressed by Google’s “aerial delivery.” It’s easy to demonstrate a show system. But it will be very hard to create a safe system that can deliver loads of a few pounds, at a distance of even a few miles, much less the 10 that Jeff Bezos apparently claimed. Or to deliver to a specific person in an apartment building.
Here’s a quick response I wrote on Andrew McAfee’s page about this.
I’m skeptical. There are real safety issues here, as well as weight/payload/power issues. To deliver a 2kg package 30 km will take a vehicle gross weight > 6 kg (rough numbers). And helicopters, unlike fixed wing, are “fail-dangerous.” Not to mention problems of delivering to a specific person in an urban environment. So I call “pie-in-the-sky” on this.
Helicopters (actually, multirotors) have very limited endurance and therefore range. You can put a big battery on them, but then you need a bigger machine to carry the weight.
They have limited payload. Four ounces is no problem; but 5 pounds requires, right now, a machine with a total span of about three feet.
At least six motors and props will be needed (called a hexacopter). Otherwise, failure of a single engine would cause an immediate crash. Even with six or more rotors, a total power failure, or a guidance failure, causes a crash. In a crash, the operator has zero control on where the machine ends up. This is unlike an aircraft.
A machine this size that crashes is big enough to kill someone underneath. Especially if some of the motors are still operating. Even professionals are very careful about what they fly over. You can see videos on Youtube of idiots flying over crowded beaches, but a few people have been badly hurt this way, and the number will grow.
Navigation using programmed routes is straightforward in clear areas, by using GPS-based-autopilots. But with obstacles (trees, buildings) a lot of development work remains. This problem, unlike the others, will be solved eventually by Moore’s Law.
If you use an aircraft (wings) instead of a copter, many of the safety issues get much better. But on the other hand, you need a much larger area to land in. You can’t land in someone’s back yard.
Most of these problems are due to laws of physics, not the capability of current electronics. In short, delivering packages is an active area of R&D, but it will be feasible only in situations where it is almost useless:
When you will be flying in unpopulated areas
When you can afford to crash, and lose, a few percent of your vehicles.
When the load is small, and the range is short.
There may be some cases that fit this description, but very few. For the next 5+ years, using drones for that don’t have to land remotely – mainly for remote sensing - is going to be the only practical application. Unless you have a military budget, of course.