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Submission Summary: 0 pending, 7 declined, 7 accepted (14 total, 50.00% accepted)

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Open Source

Submission + - Affordable, High-End, Audio-Responsive, Hackable LED Light (

Gibbs-Duhem writes: SaikoLED is a little company in the US that after 5 years of engineering, feedback, and installation experience is launching a pretty awesome open source and open hardware audio-responsive RGB+W Arduino-based LED light for a starting price of $79. The light is being launched using a new crowdfunding platform, also launched today, called Crowd Supply where you can donate now if you like.

There is a wide variety of really neat stuff in the technical blog which is also being used as a repository for general Arduino and LED Lighting know-how. Some examples which generally include both media and code are autonomous audio responsive mode, a deriviation for how to convert from HSI colorspace to RGB+W optimally, how to get 4 channels of 16-bit PWM on any ATmega32u4 based device (including Arduino Leonardo), a color changing surface that can be used as either a beautiful table for artwork or as a neuroscience tool to study the function of flicker phosphenes in generating geometric hallucinations, how to get arbitrary color correction functions using HSI colorspace, cool shades that make neat patterns on walls, and a start to extensive documentation about how the device works from a low level to a high level. On top of it all, they plan to run events like the myki Challenge and donate a portion of their lights to schools and hackerspaces if they get funded.

Submission + - How to enable 16-bit PWM output on Arduino Leonardo (

Gibbs-Duhem writes: "This tutorial has extensively commented code explaining how to configure the registers on the Arduino Leonardo to do 16-bit and 10-bit PWM outputs in hardware. It's directly written for the SaikoLED MyKi LED Light, but it's based on the Arduino Leonardo, so the same code will work for both. With 16-bit PWM output you have a lot of cool new options like arbitrary scaling functions to map an 8-bit value onto a different function, or to allow much dimmer LED light outputs. An example video showing red and blue LEDs side by side with 8-bit versus 16-bit PWM is shown here."

Submission + - Sound Responsive High Power LED Array (

Gibbs-Duhem writes: "This video shows operation of a neat project using some new digital analysis chips to produce hacker-friendly sound-responsive LED modules similar to old color organs, but much smaller, easier to set up, and modular. As usual, the boards are open-hardware, and both eagle schematics and board layouts are available on the website. The artist is constructing a 10x10 array using a Kickstarter Project, which will put out 25,000 lumens of light for a display at Burning Man. This work is from the same artist who previously built wifi LED lighting for some pretty cool installations around the country and lights with ultra-high CRI and added ultraviolet LEDs for use with artwork display."

Submission + - Autonomous Sound Responsive High Brightness LED Modules (

Gibbs-Duhem writes: "This is a cool little art project on Kickstarter where a bunch of individual high power LED lights are souped up with built in audio analysis hardware and an onboard microphone. At scale, these modules put out over 250 lumens a piece, and can be assembled into enormous arrays in any shape or size for under $50 per module for a modern version of the color organs built in analog back in the day. By the same artists who put together quite a few other cool audio oriented high power LED lighting systems, and other sophisticated lights for use with artwork previously covered on Slashdot. As usual, schematics, design information, and board layouts are available for the project."

Submission + - Ask Slashdot: How do you protect data on Android?

Gibbs-Duhem writes: "Dear Slashdot,

It makes me very nervous that my android phone has access to my email/AIM/gtalk/facebook/... protected only by a presumably fairly easily hacked geometric password protection scheme. Even more because simply attaching the phone to a USB port allows complete access to the internal memory and SD card regardless of whether a password is entered. I have no idea how much of that information ranging from cached emails to passwords stored in plaintext is accessible when mounting the device as a USB drive, and that worries me.

I have a lot of sensitive information in my email, including passwords for websites and confidential business/technical strategy discussions (not to mention personal emails ranging from racy emails from boyfriends to health discussions). My email and messaging client passwords are difficult to type (or even remember), so I would ideally want them saved in the device, although at least having something like a keyring password that needed to be re-entered after a time delay would make me feel better. This leaves me relying on encryption and OS level security to protect me.

I'm okay with this on my real laptop and computers as my hard disks are software encrypted and I make a habit of locking my session whenever I leave my desk. For instance, if I lost my laptop, the odds of the thief getting access to my information is minimal. However, I don't feel that this is at all true for my phone (which is frankly far more likely to be lost).

How is it that the slashdot security pros handle this issue? Do you just not use email or the many other incredibly convenient capabilities of new android smartphones due to the risk? Or are there specific ways in which we can guarantee (or at least greatly augment) the existing security practices?"

Submission + - ARM Based Arduino Replacement at SparkFun (

Gibbs-Duhem writes: The LeafLabs Maple, an ARM device designed to be pin compatible to the Arduino with a strikingly similar and familiar development environment has reached a new milestone — being carried by SparkFun ( By swapping the popular "avr-gcc" compiler with CodeSourcery's "arm-non-eabi-gcc," LeafLabs manages to provide a nearly identical programming experience to Arduino despite targeting a completely different architecture. Also, while some Arduino shields are incompatible due to certain capabilities being allocated to different pins, several of them are currently supported and there are more to come.

Submission + - New method to meet cost targets for solar hydrogen ( 1

Gibbs-Duhem writes: "A report commissioned by the U.S. Department of Energy has concluded that a novel University of Colorado Boulder method of producing hydrogen fuel from sunlight is the only approach among eight competing technologies that is projected to meet future cost targets set by the federal agency.

The process, which is being developed by Professor Alan Weimer's research team of CU-Boulder's chemical and biological engineering department, involves an array of mirrors to concentrate the sun's rays and create temperatures as high as 2,640 degrees Fahrenheit. The process consists of two steps — each involving reactions of a thin film of metal ferrite coating with a reactive substrate contained in a solar receiver — to split water into its gaseous components, hydrogen and oxygen."

Open Source

Submission + - Arduino based high powered LED lights over WiFi (

Gibbs-Duhem writes: This awesome video was produced by some MIT Engineers recently. They've started a fully open-source, open-hardware high power LED lighting project that they designed to be modular enough to control with the Arduino (or any other control system)! Using their open-source firmware, you can set up the Arduino to connect to WiFi and receive Open Sound Control packets. Then, they went further and released open-source software for PureData and Python to do music analysis and make the lights flash brilliantly in time with the music! A full Instructable was also posted in addition to the existing documentation for design and assembly on their website,

Submission + - MIT Engineers release Open Source LED Lighting (

Gibbs-Duhem writes: Four MIT Engineers, Brian Neltner (covered previously on slashdot for his work at ), Daniel Taub, Perry Hung, and Russel Ryan, have in their spare time taken it upon themselves to produce an open-source, flexible, modular, and extremely high power LED light based on custom open hardware, and designed to make it easy for hobbyists to start using high power lighting in their projects. The "Saiko5" ( ) is documented from circuit design and assembly all the way to case design and control software, and is all released under creative commons and GPL licenses.

The fixture they designed outputs over 800 lumens of focused LED lighting. It is controllable entirely over WiFi and is based around either an Arduino ( ) or a Maple ( ) along with their open-source and open-hardware Light Shield ( ). The firmware developed by these engineers uses the Open Sound Control ( ) protocol, a successor to the popular MIDI and DMX control schemes.

On the software side, the Saiko5 has fully open-source Python ( ) example scripts which can be used as a backend to allow any software running on the computer to control the lights with simple commands such as "flash". At a higher level, they have also released an example audio analysis patch using the open-source version of Max/MSP known as PureData ( ). The result is a variety of awesome videos showing the interaction of the LED light fixture with music which are posted at .

The authors also posted a handy Instructable ( ) with step-by-step instructions for how to construct one of these light fixtures!


Submission + - MIT student gets artistic with LED art. (

Gibbs-Duhem writes: This is some really cool artwork built by an MIT graduate student. He's designed custom LED light fixtures which are seven times brighter than the closest similar commercial models, and include colors which can't be reproduced by a normal RGB cluster (including two ridiculously bright UV LEDs) in order to create some beautiful mixed media artwork. The author's goal is to eventually publish a guide to make getting into creating such artwork more accessible to the general public.

The site includes lots of great photos and a movie of the art in action. It also has in depth descriptions of the theory involved in this relatively new form of art, an explanation of how the paints were chosen, and an in depth technical discussion of how such lights are designed with schematics and board layouts for those who might wish to build their own lights.

It's a bit heavy on the technical details for a typical artist, but it's a goldmine of experienced technical advice for an engineer looking to get into making their own LED based lighting.


Submission + - Switchgrass Ethanol produces 540% energy gain. 1

Gibbs-Duhem writes: BBC News is reporting on the first large-scale study of cellulosic ethanol using actual measured values from a 5-year study involving ten farms from three to nine hectares. The results show that ethanol derived from switchgrass contain approximately 540% more energy than is needed to produce it. Switchgrass and other fast growing crops are very attractive for cellulosic ethanol production because, unlike corn or other food crops, the entire plant is used.

The study includes real measured values for fertilizer, diesel fuel for transport, fuel used for seed production, and herbicides. The remaining energy input to be measured is the efficiency of the actual biorefineries which would convert the switchgrass cellulose to ethanol, so the study was forced to estimate those values. The numbers for that stage of the process are due out soon, with six refineries scheduled to be opened by 2010 which are "above the pilot plant scale."

Submission + - Top Inventions of 2007

Gibbs-Duhem writes: Time Magazine is reporting on the best inventions of the year. Alas, the top invention is the somewhat well-known iPhone, but there are some extremely cool projects included that I had certainly never heard of, including a device for capturing waste heat from car engines to increase efficiency up to 40%, a novel car designed to run entirely on compressed air claiming to have a range of 2000km with zero pollution, a James Bond style GPS tracking device that police can use to avoid high-speed chases, a small-scale printing press capable of printing and binding a paperback book in 3 minutes for under $3/book (and $50k per machine), a microbe-based technology for turning soft sand into sandstone, a water-based display which uses computer controlled nozzles to produce coherent gaps in the water, and a way to convert type A, B, and AB-negative blood into type O.

Submission + - Free tuition for Math, Science, and Engineering? (

Gibbs-Duhem writes: Sen. Max Baucus (Dem from MT) wants free college tuition for US math, science, and engineering majors conditional upon working or teaching in the field for at least four years.

It's difficult to see anything that pumps money into education as a bad thing, but is this the best way to help the country create a more stable, educated workforce to compete with India, China, and Canada? It certainly seems that the "trickle-down" effect could help high school education as well, as more graduates look to teaching as a way to repay their debt to society.


Submission + - MIT Drops DRM Laden Journal Subscription

Gibbs-Duhem writes: Nice to see that some market forces are working against DRM. Of course, the big difference between this situation and music is that the professors aren't being paid to submit to the journal, so the journal turning around and restricting access to that work is even more ridiculous. Here is a case where the threat of those professors no longer publishing in that journal may well be enough of a danger that the SAE removes the DRM from their software.

From the Article:

The MIT Libraries have canceled access to the Society of Automotive Engineers' web-based database of technical papers, rejecting the SAE's requirement that MIT accept the imposition of Digital Rights Management (DRM) technology.

SAE's DRM technology severely limits use of SAE papers and imposes unnecessary burdens on readers. With this technology, users must download a DRM plugin, Adobe's "FileOpen," in order to read SAE papers. This plugin limits use to on-screen viewing and making a single printed copy, and does not work on Linux or Unix platforms.

MIT faculty respond

"It's a step backwards," says Professor Wai Cheng, SAE fellow and Professor of Mechanical Engineering at MIT, who feels strongly enough about the implications of DRM that he has asked to be added to the agenda of the upcoming SAE Publication Board meeting in April, when he will address this topic.


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