Stadium Sized Cellphone Light Show Is Controlled By Sound

18 months ago, [Jameson Rader] didn’t know how to code. He had an economics degree and worked for a minor league hockey team. He did have a dream, though. Broadcasting data through sound. When we say broadcast, we mean broadcast – as in one sender and thousands of receivers.

[Jameson] didn’t have the money to hire a team to build his application. So he did what any self-respecting hacker would do. He bought a few books and taught himself to code. We’re talking about a smartphone app here, so Java and Objective-C were necessary to cover Android and iOS devices. The result is XT Audio Beacons.

[Jameson] has created a light show for stadiums which requires no new hardware infrastructure. Ultrasonic cues are added to a pre-recorded soundtrack and played over the PA system. Fans attending the show simply run an app and hold up their smartphone. The app listens for the cues and turns on the camera flash. The result is a light show which can be synchronized to music, sound effects, or whatever the event calls for. Since the system relies on sound, the App only needs permissions to access the microphone. The system would still work even if the phones were in airplane mode.

Transmitting data to smartphones via ultrasonics isn’t exactly new. Amazon uses it in their Dash Buttons, and Google uses it in their OnHub. Using it as a broadcast medium in a stadium is a novel application, though. [Jameson] also has demos showing XT Audio Beacons being used for more mundane purposes – such as troubleshooting electronics, or even as an acoustic version of an iBeacon.

Most important here is that [Jameson] isn’t keeping all this new knowledge to himself. He’s published the source to his application on Github under the MIT license.

You can see the system in action – and even try it yourself, in the video after the break.

If you want to learn more about [Jameson] and his journey, definitely check out his AMA on Reddit.

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Japanese ISS Supply Ship Dual-Purposed As Tether Experiment

When a rocket sends a capsule up with supplies for the International Space Station, they usually send a bunch of their trash back down with it, all of which burns up in the atmosphere on re-entry. But as long as you’ve got that (doomed) vehicle up there, you might as well do some science with it along the way. And that’s exactly what the Japanese Space Agency (JAXA) is doing with their Kounotori 6 supply ship that just left the ISS on Friday.

The experiment is with an electromagnetic tether that can be used to either turn electrical energy into kinetic or vice-versa. When you string a long conducting wire outwards from earth, the two ends pass through the earth’s magnetic field at different altitudes and thus pass through magnetic fields with different strengths, and an electrical potential is generated. In the KITE experiment (translated), a resistive load and an electron emitter on the supply ship are designed to burn up this electrical energy, lowering the ship’s kinetic energy, and dropping its orbit down to earth.
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Riddle: What Metal Conducts Electricity, But Not Heat?

If you can’t answer the riddle, don’t feel bad. Metal conductors usually conduct electricity and heat. Usually, that’s true, but researchers at the Department of Energy’s Lawrence Berkeley National Laboratory and at the University of California, Berkeley, have found that vanadium dioxide can conduct electricity without conducting heat.

The Wiedemann-Franz Law states that good conductors of electricity are also good conductors of heat. Vanadium dioxide not only switches from an insulator to a conductor at 67C (152F), but it appears that it also doesn’t conduct as much heat as that law predicts while it is in its electrically conductive phase.

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Autopilots Don’t Kill Drivers, Humans Do

The US National Highway Traffic Safety Administration (NHTSA) report on the May 2016 fatal accident in Florida involving a Tesla Model S in Autopilot mode just came out (PDF). The verdict? “the Automatic Emergency Braking (AEB) system did not provide any warning or automated braking for the collision event, and the driver took no braking, steering, or other actions to avoid the collision.” The accident was a result of the driver’s misuse of the technology.

quote-not-a-true-targetThis places no blame on Tesla because the system was simply not designed to handle obstacles travelling at 90 degrees to the car. Because the truck that the Tesla plowed into was sideways to the car, “the target image (side of a tractor trailer) … would not be a “true” target in the EyeQ3 vision system dataset.” Other situations that are outside of the scope of the current state of technology include cut-ins, cut-outs, and crossing path collisions. In short, the Tesla helps prevent rear-end collisions with the car in front of it, but has limited side vision. The driver should have known this.

The NHTSA report concludes that “Advanced Driver Assistance Systems … require the continual and full attention of the driver to monitor the traffic environment and be prepared to take action to avoid crashes.” The report also mentions the recent (post-Florida) additions to Tesla’s Autopilot that help make sure that the driver is in the loop.

The takeaway is that humans are still responsible for their own safety, and that “Autopilot” is more like anti-lock brakes than it is like Skynet. Our favorite footnote, in carefully couched legalese: “NHTSA recognizes that other jurisdictions have raised concerns about Tesla’s use of the name “Autopilot”. This issue is outside the scope of this investigation.” (The banner image is from this German YouTube video where a Tesla rep in the back seat tells the reporter that he can take his hands off the wheel. There may be mixed signals here.)

cropped_shot_2017-01-23-181745There are other details that make the report worth reading if, like us, you would like to see some more data about how self-driving cars actually perform on the road. On one hand, Tesla’s Autosteer function seems to have reduced the rate at which their cars got into crashes. On the other, increasing use of the driving assistance functions comes with an increase driver inattention for durations of three seconds or longer.

People simply think that the Autopilot should do more than it actually does. Per the report, this problem of “driver misuse in the context of semi-autonomous vehicles is an emerging issue.” Whether technology will improve fast enough to protect us from ourselves is an open question.

[via Popular Science].

Paper Toy Can Save Lives

Although there is a lot of discussion about health care problems in big countries like the United States, we often don’t realize that this is a “first world” problem. In many places, obtaining health care of any kind can be a major problem. In places where water and electricity are scarce, a lot of modern medical technology is virtually unobtainable. A team from Standford recently developed a cheap, easily made centrifuge using little more than paper, scrap material like wood or PVC pipe, and string.

A centrifuge is a device that spins samples to separate them and–to be effective–they need to spin pretty fast. Go to any medical lab in a developed country and you’ll find at least one. It will be large, heavy, expensive, and it will require electricity. Some have tried using hand-operated centrifuges using mechanisms like an egg beater or a salad spinner, but these don’t really move fast enough to work well. At the least, it takes a very long time to get results with a slow centrifuge.

[M. Saad Bhamla] and his colleagues at Stanford started brainstorming on this problem. They thought about toys that rotate, including a yo-yo. Turns out, those don’t spin all that fast, either. Then they considered a whirligig. We had forgotten what those are, but it is the real name for a toy that has a spinning disk and (usually) a string. When you pull on the string, the disk spins and the more you pull, the faster the disk spins. These actually have an ancient origin appearing in medieval tapestries and almost 2,500 years ago in China.

[Bhamla] found that how the toy worked was poorly understood (from a scientific standpoint)  and took pictures of one in operation with a high-speed camera. The team was able to create the “paperfuge”, a human-powered centrifuge that would spin at 125,000 RPM, enough to separate plasma from blood in under two minutes and isolate malaria parasites in 15. Some versions of the device could cost as little as twenty cents and don’t require anything more exotic than paper and string. You can see a video about the paperfuge, below.

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A Motherboard Manufacturer’s Take On A Raspberry Pi Competitor

In the almost five years since the launch of the original Raspberry Pi we have seen a huge array of competitors emerge in the inexpensive single board computer market. Many have created their own form factors, but an increasing number have gone straight for the jugular of the fruity board from Cambridge by copying its form factor and interfaces as closely as possible. We’ve seen sterling efforts from the likes of Banana Pi, Odroid, and several others, but none have yet succeeded in toppling it from its pedestal.

The ASUS Tinker specification.
The ASUS Tinker specification.

The latest contender in this arena might just make more of an impact though, because it comes from a major manufacturer, a name you will have heard of. Asus have quietly released their Tinker, board that follows the Pi form factor very closely, and packs a 1.8 GHz quad-core ARM Cortex A17 alongside an impressive spec we’ve captured as an image for this article. Though they are reticent about it on their website, there is a SlideShare presentation with some of the details, which we’ve placed below the break.

At £55 (about $68) where this is being written it’s more expensive than the Pi, but Asus go to great lengths to demonstrate that it is significantly faster. We will no doubt verify the accuracy of that claim as the boards find their way into the hands of our community. Still, it features a mostly-Pi-compatible I/O header, and the same display and camera connectors as the Pi. There is no information as to how compatible these last two are though.

Other boards in this arena have boasted impressive hardware, but have fallen down when it comes to the support for their operating systems. When you buy a Raspberry Pi it is not just the hardware you are taking on but the Raspbian operating system and its impressive community support. The Tinker supports Debian, so if Asus is to make a mark they must ensure that its support rivals that of the board it is targeting. If they succeed in that endeavor then the result can only be good news for us.

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Autodesk Moves EAGLE to Subscription Only Pricing

EAGLE user? We hope you like subscription fees.

Autodesk has announced that EAGLE is now only available for purchase as a subscription. Previous, users purchased EAGLE once, and used the software indefinitely (often for years) before deciding to move to a new version with another one-time purchase. Now, they’ll be paying Autodesk on a monthly or yearly basis.

Lets break down the costs. Before Autodesk purchased EAGLE from CadSoft, a Standard license would run you $69, paid once. The next level up was Premium, at $820, paid once. The new pricing tiers from Autodesk are a bit different. Standard will cost $15/month or $100/year, and gives similar functionality to the old Premium level, but with only 2 signal layers. If you need more layers, or more than 160 cm^2 of board space, you’ll need the new Premium level, at $65/month or $500/year.

New Subscription Pricing Table for Eagle
New Pricing Table for EAGLE

This is a bad deal for the pocket book of many users. If you could have made do with the old Standard option, you’re now paying $100/year instead of the one-time $69 payment. If you need more space or layers, you’ll likely be up to $500/year. Autodesk also killed the lower cost options for non-commercial use, what used to be a $169 version that was positioned for hobbyists.

The free version still exists, but for anyone using Eagle for commercial purposes (from Tindie sellers to engineering firms) this is a big change. Even if you agree with the new pricing, a subscription model means you never actually own the software. This model will require licensing software that needs to phone home periodically and can be killed remotely. If you need to look back at a design a few years from now, you better hope that your subscription is valid, that Autodesk is still running the license server, and that you have an active internet connection.

On the flip side of the coin, we can assume that Eagle was sold partly because the existing pricing model wasn’t doing all it should. Autodesk is justifying these changes with a promise of more frequent updates and features which will be included in all subscriptions. But sadly, Autodesk couldn’t admit that the new pricing has downsides for users:

“We know it’s not easy paying a lump sum for software updates every few years. It can be hard on your budget, and you never know when you need to have funds ready for the next upgrade.”

In their press release, they claim the move is only good for customers. Their marketing speak even makes the cliche comparison to the price of a coffee every day. Seriously.

[Garrett Mace] summarized his view on this nicely on Twitter: “previously paid $1591.21 for 88 months == $18.08/mo. Moving to $65/mo? KICAD looks better.”

We agree [Garrett]. KiCad has been improving steadily in the past years, and now is definitely a good time for EAGLE users to consider it before signing on to the Autodesk Subscription Plan™.