Root Mean Square

The first time I was in school for electrical engineering (long story), I had a professor who had never worked in the industry. I was in her class and the topic of the day was measuring AC waveforms. We got to see some sine waves centered on zero volts and were taught that the peak voltage was the magnitude of the voltage above zero. The peak to peak was the voltage from–surprise–the top peak to the bottom peak, which was double the peak voltage. Then there was root-mean-square (RMS) voltage. For those nice sine waves, you took the peak voltage and divided by the square root of two, 1.414 or so.

You know that kid in the front of the class? They were in your class, too. Always raising their hand with some question. That kid raised his hand and asked the simple question: why do we care about RMS voltage? I was stunned when I heard the professor answer, “I think it is because it is so easy to divide by the square root of two.”

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Taking Killer Robots Seriously

Killer robots are a mainstay of science fiction. But unlike teleportation and flying cars, they are something that we are likely to see within our lifetime. The only thing that’s stopping countries like the USA, South Korea, the UK, or France from deploying autonomous killing machine in the very near term is that they’re likely to be illegal under current international humanitarian law (IHL) — the rules of war.

But if you just sighed in relief that the fate of humanity is safe, think again. The reason that autonomous killing machines are illegal is essentially a technicality, and worse, it’s a technicality that’s based on the current state of technology. The short version of the story, as it stands right now, is that the only thing making autonomous robotic killing weapons illegal is that it’s difficult for a robot to tell a friend from an enemy. When technology catches up with human judgement, all bets are off.

Think I’m insane? The United Nations Office at Geneva (UNOG), the folks who bring you the rules of warfare, started up a working group on killer robots three years ago, and the report from their 2016 meeting just came out. Now’s as good a time as any to start taking killer robots seriously.

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“IoT Security” is an Empty Buzzword

As buzzwords go, the “Internet of Things” is pretty clever, and at the same time pretty loathsome, and both for the same reason. “IoT” can mean basically anything, so it’s a big-tent, inclusive trend. Every company, from Mattel to Fiat Chrysler, needs an IoT business strategy these days. But at the same time, “IoT” is vacuous — a name that applies to everything fails to clarify anything.

That’s a problem because “IoT Security” is everywhere in the news these days. Above and beyond the buzz, there are some truly good-hearted security professionals who are making valiant attempts to prevent what they see as a repeat of 1990s PC security fiascos. And I applaud them.

But I’m going to claim that a one-size-fits-all “IoT Security” policy is doomed to failure. OK, that’s a straw-man argument; any one-size-fits-all security policy is bound for the scrap heap. More seriously, I think that the term “IoT” is doing more harm than good by lumping entirely different devices and different connection modes together, and creating an implicit suggestion that they can all be treated similarly. “Internet of Things Security” is a thing, but the problem is that it’s everything, and that means that it’s useful for nothing.

What’s wrong with the phrase “Internet of Things” from a security perspective? Only two words: “Internet” and “Things”.

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Long-Term Review: Weller Magnastat Soldering Iron

One of the things you find yourself doing as a young engineer is equipping yourself with the tools of your trade. These will be the foundations upon which your career is built in a way that a diploma or degree certificate will never be, for the best degree in the world is less useful if the quality of your tools renders you unable to capitalise upon it. You may be lucky enough to make some of them yourself, but others you’ll lust after as unaffordable, then eventually put the boat out a little to buy at the limit of your meager income.

Your bench may have a few of these lifetime tools. They could be something as simple as screwdrivers or you may have one of those indestructible multimeters, but in my case my lifetime tool is my soldering iron. At some time in 1992 I spent about £60($173 back then), a lot of money for a student, on a mains-powered Weller Magnastat. The World Wide Web was still fairly fresh from Tim Berners-Lee’s NeXT in those days, so this meant a trip to my university’s RS trade counter and a moment poring over a telephone-book-sized catalogue before filling in an order slip.

The Magnastat is a simple but very effective fixed-temperature-controlled iron. The tip has a magnet on its rear end which holds closed a power switch for the heating element. When the tip has heated to the Curie temperature of the magnet, it loses its magnetism and the switch opens. The temperature falls to below the Curie temperature and the magnetism returns, the switch closes, the tip warms up again, and the cycle repeats itself. The temperature of the tip is thus dictated by the magnet’s Curie temperature, and Weller provides a range of tips fitted with magnets for different temperatures.

The result is an iron with enough power to solder heat-sucking jobs that would leave lesser irons gasping for juice, while also having the delicacy to solder tiny surface-mount components without destroying them or lifting tracks. It’s not a particularly small or lightweight iron if you are used to the featherlight pencil irons from today’s soldering stations, but neither is it too large or heavy to be unwieldy. In the nearly quarter century I have owned my Magnastat it has had a hand in almost everything I have made, from hi-fi and tube amplifiers through radio transmitters, stripline filters, kits, and too many repairs to mention. It has even been pressed into service plastic-welding a damaged motorcycle fairing. It has truly been a lifetime tool.

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Kids! Don’t Try This at Home! Robot Destroys Mankind

From the Forbin Project, to HAL 9000, to War Games, movies are replete with smart computers that decide to put humans in their place. If you study literature, you’ll find that science fiction isn’t usually about the future, it is about the present disguised as the future, and smart computers usually represent something like robots taking your job, or nuclear weapons destroying your town.

Lately, I’ve been seeing something disturbing, though. [Elon Musk], [Bill Gates], [Steve Wozniak], and [Stephen Hawking] have all gone on record warning us that artificial intelligence is dangerous. I’ll grant you, all of those people must be smarter than I am. I’ll even stipulate that my knowledge of AI techniques is a little behind the times. But, what? Unless I’ve been asleep at the keyboard for too long, we are nowhere near having the kind of AI that any reasonable person would worry about being actually dangerous in the ways they are imagining.

Smart Guys Posturing

Keep in mind, I’m interpreting their comments as saying (essentially): “Soon machines will think and then they will out-think us and be impossible to control.” It is easy to imagine something like a complex AI making a bad decision while driving a car or an airplane, sure. But the computer that parallel parks your car isn’t going to suddenly take over your neighborhood and put brain implants in your dogs and cats. Anyone who thinks that is simply not thinking about how these things work. The current state of computer programming makes that as likely as saying, “Perhaps my car will start flying and we can go to Paris.” Ain’t happening.

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Radio Shack Returns

In February 2015, Radio Shack–an icon in American malls and towns–filed for bankruptcy. You could say a lot of critical things about Radio Shack, but in many parts of the country, it was the only place you were going to go find electronic components on short notice. A lot of people of a certain age got their exposure to electronics via Radio Shack kits and parts.

Radio Shack did close a lot of stores. In fact, from 4,000 stores they are down to about 1,700. A New York hedge fund named Standard General bought all the Radio Shack assets and formed a new company (also called, oddly enough, Radio Shack). They just named [Dene Rogers] as CEO. He’s a veteran at retail sales, having been with Target in Australia and Sears in Canada.

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Hacking for Good: Watly

Here at Hackaday, we often encourage people to hack for the greater good through contests. Sure, it is fun to create a wireless barbeque thermometer or an electronic giant foam finger. At the end of the day, though, those projects didn’t really change the world, or maybe they just change a little corner of the world.

I recently saw a commercial device that made me think about how more hacker-types (including myself) ought to be working more on big problems. The device was Watly. The Italian and Spanish start up company claims the car-sized device is a “solar-powered computer.” No offense to them, but that’s the worst description for Watly that you could pick and still be accurate.

So what is Watly? It looks like some sort of temporary shelter or futuristic campsite equipment. However, it contains an array of solar cells and a very large battery. I know you are thinking, “Great. A big solar charger. Big deal.” But there’s more to Watly then just that.

The first Watly rolled out in Ghana, in Sub-Saharan Africa. About 67% of the population there–over 600 million people–do not have electricity. Nearly 40% do not have safe water. Watly uses a graphene-based filter and then uses its electricity to distill safe drinking water by boiling it. The company claims the device can deliver about 5,000 liters of safe drinking water per day.

If you read Hackaday, it is a good bet you have easy access to safe drinking water, electricity, and Internet. Think for a minute what it would be like if you didn’t. Here on the Gulf Coast of the United States, we sometimes have hurricanes or other storms that show us what this is like for a week or two. But even then, people come with water in trucks or cans. Generators show up to let you run your fridge for a few hours. Even more important: you know the situation is only temporary. What if you really thought those services would never be restored?

The portable device can provide power, water, and wireless Internet service and can last for 15 years. Watly intends to create a larger version with even more capacity.  The project received funding from the EU Horizon 2020 program that we’ve mentioned before. Creating clean water is something that can help lots of people. So is using less water. If you want some more inspiration for tackling water problems, we’ve got some links for you.