Probing CAN Bus For EV Battery Info

The widespread adoption of the CAN bus (and OBD-II) in automobiles was largely a way of standardizing the maintenance of increasingly complicated engines and their needs to meet modern emissions standards. While that might sound a little dry on the surface, the existence and standardization of this communications bus in essentially all passenger vehicles for three decades has led to some interesting side effects, like it’s usage in this project to display some extra information about an electric car’s battery.

There’s not a ton of information about it, but it’s a great proof-of-concept of some of the things CAN opens up in vehicles. The build is based on a Citroën C-Zero (which is essentially just a re-badged Mitsubishi i-MiEV) and uses the information on the CAN bus to display specific information about the state of charge of the battery that isn’t otherwise shown on the car’s displays. It also includes a build of a new secondary display specifically for this purpose, and the build is sleek enough that it looks like a standard part of the car.

While there are certainly other (perhaps simpler) ways of interfacing with a CAN bus, this one uses off-the-shelf electronics like Arduino-compatible microcontrollers, is permanently installed, and has a custom case that we really like. If you’re just starting to sniff around your own vehicle’s CAN bus, there are some excellent tools available to check out.

Thanks to [James] for the tip!

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Malamud’s General Index: Research Gist, No Slap On The Wrist

Tired of that unsettling feeling you get from looking for paywalled papers on that one site that shall not be named? Yeah, us too. But now there’s an alternative that should feel a little less illegal: this new index of the world’s research papers over on the Internet Archive.

It’s an index of words and short phrases (up to five words) culled from approximately 107 million research papers. The point is to make it easier for scientists to gain insights from papers that they might not otherwise have access to. The Index will also make it easier for computerized analysis of the world’s research. Call it a gist machine.

Technologist Carl Malamud created this index, which doesn’t contain the full text of any paper. Some of the researchers with early access to the Index said that it is quite helpful for text mining. The only real barrier to entry is that there is no web search portal for it — you have to download 5TB of compressed files and roll your own program. In addition to sentence fragments, the files contain 20 billion keywords and tables with the papers’ titles, authors, and DOI numbers which will help users locate the full paper if necessary.

Nature’s write-up makes a salient point: how could Malamud have made this index without access to all of those papers, paywalled and otherwise? Malamud admits that he had to get copies of all 107 million articles in order to build the thing, and that they are safe inside an undisclosed location somewhere in the US. And he released the files under Public Resource, a non-profit he founded in Sebastopol, CA. But we have to wonder how different this really is from say, the Google Books N-Gram Viewer, or Google Scholar. Is the difference that Google is big enough to say they’re big enough get away with it?

If this whole thing reminds you of another defender of free information, remember that you can (and should) remove the DRM from his e-book of collected writings.

Via r/technology

Medium Machine Mediates Microcontroller Messages

Connecting computers to human brains is currently limited to the scope of science fiction and a few cutting-edge laboratories. Tapping into some nerves farther from our central wetware is possible and [Peter Buczkowski] shows us his stylish machine for implanting a pattern into our brains without actively having to memorize anything.

His Medium Machine leverages a TENS unit to activate forearm muscles in a pattern programmed into an Arduino. Users place their forearm across two aluminum electrodes mounted on a tasteful wooden platform and extend a single finger over a button. Electrical impulses trigger the muscles which press the button. That’s all. After repeating the pattern a few times, the users should be able to recite it back on command even if they aren’t aware of what it means. If this sounds like some [Johnny Mnemonic] memory cache, you are absolutely correct. This project draws inspiration from the [William Gibson] novel which became a [Keanu Reeves] movie.

Users can be programmed with a Morse code message or the secret knock to open an attic library or play a little tune. How about learning a piano song?

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InfoFuse

This Message Will Self Destruct… As You Read It?

A group of Harvard chemists have come up with a novel use for fire. Through experimentation, they have been able to build what they call an InfoFuse. As the name implies, it’s essentially a burning fuse that can “transmit” information.

The fuse is made from flash paper, which is paper made from nitrocellulose. Flash paper burns at a relatively constant speed and leaves no smoke or ash, making it ideal for this type of project. The chemists developed a method of conveying information by changing the color of the flame on the paper. You might remember from high school chemistry class that you can change the color of fire by burning different metal salts. For example, burning copper can result in a blue flame. This is the key to the system.

The researchers dotted the flash paper with small bits of metal salts. As the flame reaches these spots, it briefly changes colors. They had to invent an algorithm to convert different color patterns to letters and numbers. It’s sort of like an ASCII table for fire. Their system uses only three colors. The three colors represent eight possible combinations of color at any given time. Just two quick pulses allow the researchers to convey all 26 letters of the English alphabet as well as ten digits and four symbols. In one test, the researchers were able to transmit a 20 character message in less than 4 seconds.

[Ben Krasnow] found the Harvard project and just had to try it out for himself. Rather than use colors to convey information, he took a more simple approach. He started with a basic strip of flash paper, but left large tabs periodically along its length. As the paper burns from end to end, it periodically hits one of these tabs and the flame gets bigger momentarily.

[Ben] uses an optical sensor and an oscilloscope to detect the quantity of light. The scope clearly shows the timing of each pulse of light, making it possible to very slowly convey information via fire. Ben goes further to speculate that it might be possible to build a “fire computer” using a similar method. Perhaps using multiple strips of paper, one can do some basic computational functions and represent the result in fire pulses. He’s looking for ideas, so if you have any be sure to send them his way! Also, be sure to check out Ben’s demonstration video below. Continue reading “This Message Will Self Destruct… As You Read It?”