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Jack Cover, Inventor of the Taser

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Welcome to the second installment of Retrobituaries! DB Grady's new column looks back at the lives of interesting (but not crazy famous) people who are no longer with us.

You might not know Jack Cover, but you’re probably familiar with the Taser, a device he invented to help stop airplane hijackings. (He didn’t think sky marshals firing bullets in an airplane at 30,000 feet was such a good idea.) But his contributions didn’t stop there, and the next time you resist arrest, you can tell the cops not only where the Taser they’re using came from, but also a little about the man who created it. Here is a look at the life of John “Jack” Higson Cover, Jr.

He was influenced by Victor Appleton.

In 1910, publisher Stratemeyer Syndicate released the first in a series of novels featuring an intrepid young boy named Tom Swift who used science to solve mysteries. These books have inspired generations of budding scientists, from Steve Wozniak to Isaac Asimov. Interestingly, there is no such person as Victor Appleton, who is credited as the series author. The books were actually ghostwritten by several men and women, but always under the name Victor Appleton.

In the case of Jack Cover, when he needed to name his newest invention, he recalled his childhood inspiration, and called the device “Thomas A. Swift's Electric Rifle,” or, abbreviated, TASER.

He helped put the first man on the moon.

In the early 1960s, Jack Cover was the chief scientist at North American Aviation, an aerospace engineering and manufacturing firm. His work would lead to an enduring relationship with a new government agency called NASA. Among North American Aviation’s most notable contributions to the space program are the second stage of the Saturn V rocket, and the Apollo Command/Service Module.

He had no fear.

If there is a list of really, really dangerous jobs out there, “test pilot” has to be somewhere near the top. A test pilot’s job basically entails climbing into the cockpit of an experimental aircraft and pushing the throttle all the way forward. The thing about experimental aircraft is that you never knew whether it would fall apart or explode or crash or what. If you knew for certain that a plane wouldn’t suddenly fall out of the sky, you wouldn’t be a test pilot. You would just be a pilot. Anyway, that was Jack Cover’s job with the Army Air Forces during World War II. Later, he served at the Inyokern Naval Ordnance Test Station. Have you ever lit the fuse of a bottle rocket only to have it explode immediately, stinging your hand? That’s what you do at military ordnance test stations, only instead of tiny firecrackers, you’re working with giant bombs, and instead of stinging your hand, you’re vaporized.

While we’re on the subject of World War II and giant bombs: I’m not saying there is a direct link between the atomic bomb and the Taser, but...


If you haven’t figured it out by now, Jack Cover is basically the Chuck Norris of scientists. (Probably said at the time: “When Jack Cover jumps in a swimming pool, he doesn’t get wet; the water gets Jack Cover.”) So of course he didn’t just enroll in college and learn from ordinary tenure-chasing physics professors. While earning his PhD, he was taught by Enrico Fermi, who had previously won the Nobel Prize in Physics for "demonstrations of the existence of new radioactive elements produced by neutron irradiation, and for his related discovery of nuclear reactions brought about by slow neutrons.” As if that weren’t enough, Cover was also taught by Edward Teller, who was notable for predicting the Jahn–Teller effect, and later, the Brunauer–Emmett–Teller isotherm.

Also, Teller is the father of the hydrogen bomb, and Fermi is often called the father of the atomic bomb.

With such a pedigree, we’re probably lucky that Jack Cover stopped with a ranged stun gun.

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iStock // Ekaterina Minaeva
Man Buys Two Metric Tons of LEGO Bricks; Sorts Them Via Machine Learning
May 21, 2017
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iStock // Ekaterina Minaeva

Jacques Mattheij made a small, but awesome, mistake. He went on eBay one evening and bid on a bunch of bulk LEGO brick auctions, then went to sleep. Upon waking, he discovered that he was the high bidder on many, and was now the proud owner of two tons of LEGO bricks. (This is about 4400 pounds.) He wrote, "[L]esson 1: if you win almost all bids you are bidding too high."

Mattheij had noticed that bulk, unsorted bricks sell for something like €10/kilogram, whereas sets are roughly €40/kg and rare parts go for up to €100/kg. Much of the value of the bricks is in their sorting. If he could reduce the entropy of these bins of unsorted bricks, he could make a tidy profit. While many people do this work by hand, the problem is enormous—just the kind of challenge for a computer. Mattheij writes:

There are 38000+ shapes and there are 100+ possible shades of color (you can roughly tell how old someone is by asking them what lego colors they remember from their youth).

In the following months, Mattheij built a proof-of-concept sorting system using, of course, LEGO. He broke the problem down into a series of sub-problems (including "feeding LEGO reliably from a hopper is surprisingly hard," one of those facts of nature that will stymie even the best system design). After tinkering with the prototype at length, he expanded the system to a surprisingly complex system of conveyer belts (powered by a home treadmill), various pieces of cabinetry, and "copious quantities of crazy glue."

Here's a video showing the current system running at low speed:

The key part of the system was running the bricks past a camera paired with a computer running a neural net-based image classifier. That allows the computer (when sufficiently trained on brick images) to recognize bricks and thus categorize them by color, shape, or other parameters. Remember that as bricks pass by, they can be in any orientation, can be dirty, can even be stuck to other pieces. So having a flexible software system is key to recognizing—in a fraction of a second—what a given brick is, in order to sort it out. When a match is found, a jet of compressed air pops the piece off the conveyer belt and into a waiting bin.

After much experimentation, Mattheij rewrote the software (several times in fact) to accomplish a variety of basic tasks. At its core, the system takes images from a webcam and feeds them to a neural network to do the classification. Of course, the neural net needs to be "trained" by showing it lots of images, and telling it what those images represent. Mattheij's breakthrough was allowing the machine to effectively train itself, with guidance: Running pieces through allows the system to take its own photos, make a guess, and build on that guess. As long as Mattheij corrects the incorrect guesses, he ends up with a decent (and self-reinforcing) corpus of training data. As the machine continues running, it can rack up more training, allowing it to recognize a broad variety of pieces on the fly.

Here's another video, focusing on how the pieces move on conveyer belts (running at slow speed so puny humans can follow). You can also see the air jets in action:

In an email interview, Mattheij told Mental Floss that the system currently sorts LEGO bricks into more than 50 categories. It can also be run in a color-sorting mode to bin the parts across 12 color groups. (Thus at present you'd likely do a two-pass sort on the bricks: once for shape, then a separate pass for color.) He continues to refine the system, with a focus on making its recognition abilities faster. At some point down the line, he plans to make the software portion open source. You're on your own as far as building conveyer belts, bins, and so forth.

Check out Mattheij's writeup in two parts for more information. It starts with an overview of the story, followed up with a deep dive on the software. He's also tweeting about the project (among other things). And if you look around a bit, you'll find bulk LEGO brick auctions online—it's definitely a thing!

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Name the Author Based on the Character
May 23, 2017
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