Self-driving cars may take decades to prove safety: Not so.

Proving self-driving cars are safe could take up to hundreds of years under the current testing regime, a new Rand Corporation study claims. Source: Self-driving cars may not be proven safe for decades: report  The statistical analysis in this paper looks fine, but the problem is even worse for aircraft (since they are far safer per mile than autos.) Yet new aircraft are sold after approx 3 years of testing, and less than 1 million miles flown. How?

From the report:

we will show that fully autonomous vehicles would have to be driven hundreds of millions of miles and sometimes hundreds of billions of miles to demonstrate their reliability in terms of fatalities and injuries. Under even aggressive testing assumptions, existing  fleets would take tens and sometimes hundreds of years to drive these miles.

How does the airline industry get around the analogous statistics? By understanding how aircraft fail, and designing/testing for those specific issues, with carefully calculated specification limits. They don’t just fly around, waiting for the autopilot to fail!

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How to reduce chances of a hoverboard fire

Wired has a good article on fires from “hoverboards,” which are essentially very small hands-free electric scooters. Here is an example. Start at about the :30 mark to see how these devices explode, and can easily set a house on fire.


Neither Wired nor other news stories have much constructive advice about how to reduce the chance of fires. As they point out, buying a well-made model is important, but at present there is no way to distinguish the well-made ones from the knock-offs. And most are cheap knock-offs by companies that will be gone in a year.

I have some experience with the underlying cause of these fires,  their Lithium-based batteries, because I use them in radio controlled aircraft. Fires of these batteries are not common, but they happen. Two people in San Diego who I know directly have had major fires. One lost a 2-unit condo, the other a detached workshop. The second one happened to an expert in RC flying!

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Computers don’t belong in classrooms?!

I recently audited some lectures by friend and China expert Prof. Susan Shirk. She bans computers in her lectures. But one student sitting near me had his machine out and was “busy” with the usual distractions. (Didn’t he know the Associate Dean was a few seats away?) I asked Susan about him after class. “He told me he can’t take notes without a computer.” Obviously  the computer  is not the big issue on his note taking. Actually, it probably IS the issue – but in a negative way.

Not one computer mirrors the overheads.

James Kwak has beaten the distraction of cell phones – by removing most apps, including browsers.

I know that its enormous powers of distraction also make me lose focus on work, tune out in meetings, stay up too late at night, and, worst of all, ignore people in the same room with me. We all know this. We’re addicted to the dopamine hit we get when we look at our email and there’s actually something good in there, so we keep checking our email hoping to feel it again.

via How I Achieved Peace by Crippling My Phone — Bull Market — Medium.

Clay Shirky, an Internet sociologist, has a good discussion of why he recently banned computers  in his classrooms. Excerpt:

I came late and reluctantly to this decision — I have been teaching classes about the internet since 1998, and I’ve generally had a laissez-faire attitude towards technology use in the classroom. This was partly because the subject of my classes made technology use feel organic, …. And finally, there’s not wanting to infantilize my students, who are adults, even if young ones — time management is their job, not mine.

Despite these rationales, the practical effects of my decision to allow technology use in class grew worse over time. The level of distraction in my classes seemed to grow, even though it was the same professor and largely the same set of topics, …

Over the years, I’ve noticed that when I do have a specific reason to ask everyone to set aside their devices (‘Lids down’, in the parlance of my department), it’s as if someone has let fresh air into the room. The conversation brightens, and more recently, there is a sense of relief from many of the students. Multi-tasking is cognitively exhausting — when we do it by choice, being asked to stop can come as a welcome change.

So this year, I moved from recommending setting aside laptops and phones to requiring it, adding this to the class rules: “Stay focused. (No devices in class, unless the assignment requires it.)” …

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Comparing OCR program compression: PDFpen, Acrobat, and Abbyy Finereader

I have been doing a lot of OCR, as I study more than 100 old aircraft manuals to see how aviation procedures evolved. I have them all in a database, and it’s useful to search the DB for key terms like V1 and density altitude. In the end, no single OCR program did everything, and I have ended up with 3. (OCR = Optical Character Recognition = takes scanned documents and makes them searchable, copyable, etc.) Here are some notes on my experience, with the goal of saving time for others in the future.  Continue reading

NYT review of photo drone recommends illegal and unsafe behavior

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.

If you have the $1200 for one of these undeniably cool machines, and the interest, the best approach is simple: buy one, and give it to me.  More seriously, here’s some good advice about learning to do photography with these.  It’s written for photographers who fundamentally are not interested in the flying part, and it’s not nearly “sufficient” for safety, but it gives a good idea of what you are in for.

Here are two videos of idiots flying these vehicles and having nasty crashes.  After the break: my two exchanges with the NY Times about the article.

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Amazon is blowing smoke about drone delivery

Amazon Delivers Some Pie in the Sky – 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.

I see others are being skeptical because of regulatory problems. Yet other countries are way ahead of U.S. on regulation, and I don’t think regulation is the fundamental problem. The real problems include safety and payload:

  • 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.

 

Will MOOCs revolutionize education? History says the odds are against it.

MOOCs – Massively Open Online Courses – are well up in the hype cycle right now. Coursera, Udacity, and other companies are trying to establish themselves as leaders in this “emerging market,” following the 1999 model of build the traffic first, then figure out how to monetize it. (That model worked fine for Google and Facebook, and failed for many others – but that’s a separate topic.) The expansive vision is that instead of showing up in classrooms to listen to a professor, students will “engage in online learning” including lectures and discussions over the Net. If they are in conventional colleges, they will still come to class, but it will be to discuss and go beyond the lectures they received the night before.

A recent post on another blog about the Open TV course movement reminded me that TV was once receiving similar game-changing forecasts. I’m sure it accomplished a little, but it never got much traction and came nowhere close to its hype. The post was on Punk Rock OR, and it gives some history that I didn’t know, about education by TV.

The history of education in American is littered with 1) fads of all kinds, and specifically 2) claims that XYZ new communication technology would revolutionize higher education. Examples include radio, mail-order courses, TV, movies, Control Data’s instruction system that used a time-shared computer, the Internet in general, the World Wide Web (that one is partly accurate). Many of these have had some value, but none of them has changed the basic paradigm of “asses in classrooms,” or if they have, they did not reach even a 1% market share. Notice that all of these have the same principle: achieve economies of scale, by using the faculty member far beyond where his or her physical voice can carry.

Yes, technology has helped education, and sometimes has even revolutionized it. Two old examples are the printing press, and the pencil. (Does anyone know a source for the explanation, by a school board, of why paper and pencils were unnecessary expenses, given that a chalkboard was perfectly adequate for teaching writing? I read about this many years ago.)

 But true revolutions in education are very rare. An example of a computer-revolution-that-hasn’t-happened: discussion conferences where discussions continue after class. These are technically straightforward, and the infrastructure exists and is used (e.g. Blackboard and others). So far, I have seen approximately zero examples of massive changes created by such discussions, for all their promise.

So I take the lack of impact from MOTVCs as yet another bad sign for MOOCs. Many of these forecast revolutions in higher ed, including TV and courses-by-mail, have foundered because there is something superior about actually showing up in a classroom, surrounded by other people talking about the same subject. We don’t really know why it’s superior – but so far, the replacements have not kept students coming back. Is there much reason to think “this time it’s different?”

Tieing this to technological knowledge and art/science, the main topics of this blog, good teaching apparently contains elements that are still very much art. Perhaps it’s as simple as the observation that humans, as social animals, use our brains differently when we are in groups.