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Look What Showed Up For Bring-A-Hack At OSH Park

อาทิตย์, 10/16/2016 - 00:01

Hackaday was in Portland last weekend for the Open Hardware Summit. I did a brief recap earlier this week but this post has been on my mind the entire time. The night before the summit, OSH Park (the Purveyors of Perfect Purple PCBs which we all know and love) hosted a Bring-A-Hack at their headquarters. [Laen] knows how to throw a party — with a catered spread and open bar which all enjoyed. The place was packed with awesome hackers, and everyone had something amazing to show off.

In fact, there were far too many people showing off hardware for me to capture all in one evening. But join me after the jump for six or seven examples that really stuck out.

We have been running into [Louis Beaudoin] all over the place for the last couple of years. He’s the one behind SmartMatrix, which I used for my 1-Pixel Pacman project. He brought along with him a project based around the Particle Photon (a WiFi dev board) which drives APA102 LEDs. You can check out the software he’s been working on, but the breakout board for the Photon is what caught my eye. It appears that the pin headers on the Photon plug into a 0.1″ pitch protoboard. On the bottom you can see the trick is a set of surface mount headers that allow through-hole to pass right… through. Cool!

Here’s something aimed at the FPV RC scene (think quadcopter racing and the like). [Shea Ivey] is developing modules to extend the functionality of Fat Shark RC vision glasses. These head-mounted displays have an expansion port on them. The module he was demoing connects to the camera output on the quadcopter (it’s a super-small board not pictured here) and can overlay any info you want on the display — compass, altitude, battery, etc. The module itself has a screen and user control for choosing what settings you want to use.

I first bumped into [Josh Sharpe] at CES last year and was glad to see him again at this meetup. His company is moving toward release with a car hacker’s dream. It plugs into the ODB-II port and has all kinds of goodies, like an SD card slot, and a ZigBee header loaded up with an ESP32. [Josh] isn’t running the CAN on the ESP32; he has a transceiver for that and the latest and greatest in Bluetooth+WiFi chips is just that – a WiFi and Bluetooth interface. The red board he’s showing off is super interesting; it’s the first time I’ve seen an ESP32 in the wild and it’s not one of the dev boards we’ve previously encountered.

At OSH Park they spin panels of PCBs and then separate them for shipping to a lot of different customers. That means scrap from panel edges and what isn’t able to be “tetris’d” into useful space. I like it that they didn’t get rid of their recycling before the party because it’s impressive to see this huge scrap bin.

There were a ton of OSH Park boards on display, but this crown seemed especially awesome to me!

Meet the Internet of Fuzzy Dice which [Scott Dixon] brought along to the party. They use Rigado BMD-200 modules to connect the dice to the display. Roll the dice and the resulting up-face will be shown on the display which is housed in a repurposed enclosure which looks fantastic!

You can find [Zack Fredin] hanging out on Hackaday.io quite often by the name of [zakqwy]. He is the mind behind NeuroBytes (Best Product finalist in the 2015 Hackaday Prize). Check out what he calls a “weekend novelty project” — this POV wristwatch with a spectacularly dense set of hand-soldered SMD LEDs. Wow!

I couldn’t get a good camera shot of the display as he twisted his wrist to-and-fro, but it was easy to make out with the eye. The image here is from his project page. The wristbands are wires with JST connectors. There are three boards, the brain board hosts a Teensy 3.2, the LED board uses shift registers driven by SPI, and the battery board on the bottom  is a bit hacked together just to really win our hearts. This is an epic build, go give him a like on his page!!

While you’re there, check out the technique he uses for rapid-prototyping with copper clad. The plane is broken up by cuts of an X-ACTO knife. It’s intriguing and anyone who will be a the Hackaday SuperConference should seek him out — he’ll be helping lead badge hacking and I bet we can convince him to do some mini-seminars on the technique.

This cool little kit, called the COSMOneer is about to go into crowdfunding. It seeks to get kids excited about cube satellites. You assemble the kit and hang it by a little thread, then a motor acting as a flywheel is used to show how these can change their orientation while orbiting the earth. For this demo the balance is calibrated by adding or removing pennies and the power is transferred wirelessly. There’s a bunch of different interesting concepts, surely one of them will turn a middle schooler’s head.

[Eric Pan], CEO of Seeed Studio brought along a ReSpeaker board with him. It was running a little hack to light up different sides of the board based on where sound is coming from. In talking to him about it I started to get really excited about the potential for this board. For instance, he mentioned it has the capability to recognize who is speaking to it. So a good software hack will let you plop it down on the conference table next to the phone and it can let everyone on the conference call know who it is that is speaking.

I missed so much!

There was so much more on display. It’s too bad that I didn’t have more time to see everything, but I also wanted to chew the fat with all of these awesome people. Always have a hack in progress because you don’t want to miss an opportunity to attend a Bring-A-Hack like this one!

Filed under: cons, Featured

Hacker Helps His Mother Lift Her Walker When He’s Not There

เสาร์, 10/15/2016 - 22:31

[typo]’s mother gets around with a walker. It’s a great assistive device until she has to lift the heavy thing up into her car. Noting that this was a little cruel he did as any hacker would and found a way to automate the process.

The build is pretty cool. She had to give up her passenger seat, but it’s a small price to pay for independence. He removed the door paneling on the passenger side. Then he welded on a few mounting points. Next he had to build the device.

The well-built device has a deceptively simple appearance. The frame is made from CNC milled panels and the ever popular aluminum extrusion. It uses a 12V right angle drive and some belting to lift the chair. There’s no abundance of fancy electronics here. A toggle switch changes the direction of the motor. There are some safety endstops and an e-stop.

Now all she has to do is strap the walker to the door. She picks the direction she wants the lift to go and presses a button. After which she walks the short distance to the driver’s seat, and cruises away.

Filed under: car hacks, Medical hacks

Amazon Dash Reboots Your Pi

เสาร์, 10/15/2016 - 21:01

We all know feature creep can be a problem in almost any project. A simple idea can often become unusable if a project’s scope isn’t clearly defined in the beginning. However, the opposite problem sometimes presents itself: forgetting to include a key feature. [Zach] had this problem when he built a Raspberry Pi magic mirror and forgot to build a physical reset/shutoff switch. Luckily he had a spare Amazon Dash button and re-purposed it for use with his Pi.

The Raspberry Pi doesn’t include its own on/off switch. Without installing one yourself, the only way to turn off the device (without access to the terminal) is to unplug it, which can easily corrupt data on the SD card. Since [Zach]’s mirror was already complete, he didn’t want to take the entire thing apart just to install a button. There’s already a whole host of applications for the Dash button, so with a little Node.js work on the Raspberry Pi he was able to configure a remote-reset button for his mirror.

This is a similar problem for most Raspberry Pi owners, so if you want to follow [Zach]’s work he has done a great job detailing his process on his project site. If you’re looking for other uses for these convenient network-enabled buttons, he also links to a Github site with lots of other projects. This pizza button is probably our favorite, though.

Filed under: Raspberry Pi

A Lot Of WiFi Power, A Yagi, And A Sniper’s ‘Scope

เสาร์, 10/15/2016 - 18:01

Do you remember the early days of consumer wireless networking, a time of open access points with default SSIDs, manufacturer default passwords, Pringle can antennas, and wardriving? Fortunately out-of-the-box device security has moved on in the last couple of decades, but there was a time when most WiFi networks were an open book to any passer-by with a WiFi-equipped laptop or PDA.

The more sophisticated wardrivers used directional antennas, the simplest of which was the abovementioned Pringle can, in which the snack container was repurposed as a resonant horn antenna with a single radiator mounted on an N socket poking through its side. If you were more sophisticated you might have used a Yagi array (a higher-frequency version of the antenna you would use to receive TV signals). But these were high-precision items that were expensive, or rather tricky to build if you made one yourself.

In recent years the price of commercial WiFi Yagi arrays has dropped, and they have become a common sight used for stretching WiFi range. [TacticalNinja] has other ideas, and has used a particularly long one paired with a high-power WiFi card and amplifier as a wardriver’s kit par excellence, complete with a sniper’s ‘scope for aiming.

The antenna was a cheap Chinese item, which arrived with very poor performance indeed. It turned out that its driven element was misaligned and shorted by a too-long screw, and its cable was rather long with a suspect balun. Modifying it for element alignment and a balun-less short feeder improved its performance no end. He quotes the figures for his set-up as 4000mW of RF output power into a 25dBi Yagi, or 61dBm effective radiated power. This equates to the definitely-illegal equivalent of an over 1250W point source, which sounds very impressive but somehow we doubt that the quoted figures will be achieved in reality. Claimed manufacturer antenna gain figures are rarely trustworthy.

This is something of an exercise in how much you can push into a WiFi antenna, and his comparison with a rifle is very apt. Imagine it as the equivalent of an AR-15 modified with every bell and whistle the gun store can sell its owner, it may look impressively tricked-out but does it shoot any better than the stock rifle in the hands of an expert? As any radio amateur will tell you: a contact can only be made if communication can be heard in both directions, and we’re left wondering whether some of that extra power is wasted as even with the Yagi the WiFi receiver will be unlikely to hear the reply from a network responding at great distance using the stock legal antenna and power. Still, it does have an air of wardriver chic about it, and we’re certain it has the potential for a lot of long-distance WiFi fun within its receiving range.

This isn’t the first wardriving rifle we’ve featured, but unlike this one you could probably carry it past a policeman without attracting attention.

Filed under: radio hacks

Not Just Another Alarm Clock

เสาร์, 10/15/2016 - 15:01

Even though [Stefan] sent in this link with the heading “Another Sunrise Alarm Clock“, it’s anything but plain. Sure, from the outside it looks like a simple and refined design, but the story of getting there is hardly straightforward.

Take that nice-looking luminous dial. [Stefan] made it himself, using the same techniques that he’s used for making his own watch faces. (Amazingly, he prints them out on a color ink-jet.) This is a sunrise wake-up clock, but if the bright LEDs don’t wake him up, there’s also a vintage DIY synthesizer project stuffed in the box in place of a cheap piezo buzzer. Even the wooden case shows attention to detail — it has nice edging done on a router table.

So yeah, we’ve all seen clocks before. But this one is very personal, melding together a few of [Stefan]’s hobbies into one useful, and good-looking, device.

Filed under: clock hacks

Hackaday Prize Entry: FLipMouse

เสาร์, 10/15/2016 - 12:00

The theme of the last Hackaday Prize challenge was Assistive Technologies, and with this comes technical solutions for people with severe motor restriction. One of the best we’ve seen is a device designed to use a sip and puff interface and buttons to control a cursor through USB. The almost too clever name for a device meant to be used via fingers or lips is the FLipMouse, and right now it’s in the running for the finals in the Hackaday Prize.

The FLipMouse isn’t so much a mouse as it is a very long and very sensitive joystick. The main method of interaction is a long, hollow tube wrapped with force sensors. These force sensors, like those seen in the Nintendo Power Glove or this other Hackaday Prize entry, turn the tube into an exceptionally sensitive joystick, meant to be gripped by the user’s lips. This tube is hollow, too, so a sip-and-puff interface is used to register right and left clicks. Of course, there are a few external buttons that may be remapped to anything.

How useful is it? This mouth-based mouse seems to be exceptionally capable. In the video below, [Harry Hötzinger] plays a synthesizer live on stage using a step sequencer and a mouse-controlled synth interface. It’s all highly optimized for the specific piece of music, but it is an incredible display of what you can do with a laser cutter and a Digikey BOM.

The HackadayPrize2016 is Sponsored by:
Filed under: The Hackaday Prize

Raspberry Pi Want a Cracker?

เสาร์, 10/15/2016 - 09:00

If you watch the old original Star Trek, you’ll notice that the computers on board the Enterprise don’t look much like our computers (unless you count the little 3.5 inch floppies that looked pretty close to the real thing). Then again, the Enterprise didn’t need keyboards and screens since the computers did a pretty good job of listening and speaking to humans.

We aren’t quite to the point where you can just ask the computer some fuzzy open-ended question like Captain Kirk did, but we do have things like Echo, Siri, and Google Now that do a fair job of listening to you and replying. In fact, Google provides an API that can do speech recognition and generation. [Giulio] used some common Python libraries to add speech I/O to a Raspberry Pi.

The example he shows is a virtual parrot. Of course, you could do that entirely with audio, but the way [Giulio] did it, the parrot generates strings of text and then speaks them. So it isn’t hard to imagine processing the text in some way.

Of course, there are hardware options. Or, snag an Alexa and see if you can snag a few million dollars in prizes.

Filed under: Raspberry Pi

Counting Eggs With A Webcam

เสาร์, 10/15/2016 - 06:00

You’ll have to dig out your French dictionary (or Google translate) for this one, but it is worth it. [Nicolas Giraud] has been experimenting with ways to use a webcam to detect the number of eggs chickens have laid in a chicken coop. This page documents these experiments using a number of different algorithms to automatically detect the number of eggs and notify the owner. The system is simple, built around a Pi running Debian Jesse Lite and a cheap USB webcam. An LED running off one of the GPIO pins illuminates the eggs, and the camera then captures the image for analysis.

[Nicolas] tried detecting colors and blob detection (used by microbiologists to count cells on slides), but they didn’t work well against the uneven background of the straw. Finally, he settled on using a technique called Local Binary Patterns, where the system looks at the relationship of an area and the areas around it, searching for a specific pattern created by the round shape and color gradient of the egg. After some tweaking, he claims a 100% success rate.

His work is part of a project called Eggs-iting, which is designing an easy to use chicken coop that anyone can build and use in their back yard. I’ve had chickens, and have traipsed out in the rain and snow to get the eggs, only to find that the hens were not in the mood and hadn’t laid yet. So, a simple system that lets me know how many eggs to expect sounds perfect.


Filed under: green hacks

Microwave Ovens Turn You into Spiderman

เสาร์, 10/15/2016 - 03:00

Want to climb a wall like Spiderman? No problem – just whip up a climbing rig with microwave oven transformers. And find a steel building. And rewrite the canon so that Peter Parker is bitten by an electromagnetic spider instead of a radioactive one.

Back in the reality-based world, you’d probably be taking you life in your hands if you use [Make It Extreme]’s rig to get more than a dozen feet above the ground. The basics are pretty sound, but the devil is in the details. Four MOTs are cut and stripped of their secondary coils and attached to fixtures for the feet and hands. A backpack full of gel cell batteries powers the rig, and simple normally closed switches in the handholds control both the foot and hand magnets on a side.  A click of a switch releases the magnets on one side, allowing the climber to reach up.

And therein lies our safety beef: what happens when you make a mistake and push both buttons at the same time? Seems like this build is screaming for some control circuitry that prevents this most obvious failure mode. We’re not ones to throw an Arduino at every problem, but in this case it may make sense, especially when it could monitor your time left before cratering the charge remaining in the battery pack.

Still, like most dangerous stunts, this looks really cool. If you’ve got any ideas for improvements in the controls, leave them in the comments below. And if you’re interested in transforming yourself into a superhero, learn from a guy who’s actually doing it – our own [James Hobson]. Check out some of his builds, like the Captain America shield or his car-lifting exoskeleton.

Filed under: misc hacks

Graphene Refractions

เสาร์, 10/15/2016 - 01:31

Researchers recently observed negative refraction of electrons in graphene PN junctions. The creation of PN junctions in graphene is quite interesting, itself. Negative refraction isn’t a new idea. It was first proposed in 1968 and occurs when a wave bends–or refracts–the opposite way at an interface compared to what you would usually expect. In optics, for example, this can allow for refocusing divergent waves and has been the basis for some proposed invisibility cloaking devices.

In theory, negative refraction for electrons should be easy to observe at PN junctions, but in practice, the band gap voltage causes most electrons to reflect at the junction instead of refract. However, a graphene PN junction has no band gap voltage, so it should be ideal. However, previous attempts to find negative refraction in graphene were not successful.

[Cory Dean] and his team at Columbia theorized that the problem was atomic-scale roughness at the interface caused by the fabrication technique most researchers use. They likened the effect to a scratched piece of glass.  To combat it, they used a natural edge of a graphene flake to form the junction and found clear evidence of refraction.

The team hopes to investigate practical applications. One possible use would be as a very low power electronic switch by bringing an electron beam to focus at two different points.

We’ve seen a lot of research into making graphene more practical. We’ve also seen novel applications. Who knows what’s next?

Filed under: chemistry hacks, news

Program Your Brain, Hack Your Way to Productivity

เสาร์, 10/15/2016 - 00:00

Most people wish they were more productive. Some buckle down and leverage some rare facet of their personality to force the work out. Some of them talk with friends. Some go on vision quests. There are lots of methods for lots of types of people. Most hackers, I’ve noticed, look for a datasheet. An engineer’s reference. We want to solve the problem like we solve technical problems.

It’s got the cover equivalent of click-bait, but the centimeter thick bibliography listing research sources at the back won me over.

There were three books that gave me the first hints at how to look objectively at my brain and start to hack on it a little. These were The Power of Habit by Charles Duhigg, Flow By Mihaly Csikszentmihalyi, and Getting Things Done By David Allen.

I sort of wandered into these books in a haphazard path. The first I encountered was The Power of Habit which I found to be a bit of a revelation. It presented the idea of habits as functions in the great computer program that makes up a person. The brain sees that you’re doing a task over and over again and just learns to do it. It keeps optimizing and optimizing this program over time. All a person needs to do is trigger the habit loop and then it will run.

For example: Typing. At first you either take a course or, if your parents left you alone with a computer for hours on end, hunt-and-peck your way to a decent typing speed. It involves a lot of looking down at the keyboard. Eventually you notice that you don’t actually need to look at the keyboard at all. Depending on your stage you may still be “t-h-i-n-k-i-n-g”, mentally placing each letter as you type. However, eventually your brain begins to abstract this away until it has stored, somewhere, a combination of hand movements for every single word or key combination you typically use. It’s only when you have to spell a new word that you fall back on older programs.

There are a few good youtube videos explaining how to pronounce his name.

But the more revelatory section of “The Power of Habit” is the scope at which habits are involved in daily life. Everything from deep meaningful conversations with a friend to tying shoe laces could be a program written by you or someone in your past. This also means that new habits can be written. A person can intentionally choose a new way of doing things. So the way we express our sentience is not through our everyday lives but how we program ourselves to behave. If we want to stop a bad habit we just need to understand what triggers it and then either avoid those triggers or have them trigger a new piece of code. This was a concept clearly within a hacker’s reach.

Which brings me to the second book. Flow by Mihaly Csikszentmihalyi. Mihaly set out to find what makes people happy. Not the sort of, “I just heard a funny joke,” happy, but the kind where someone describes themselves as content with their lot in the world. Now, this is not a man writing a get-rich-quick self-help book. This is a real scientist publishing a lifetime of research, and he makes a convincing argument. He found a common thread in the way people approach their work. I’m simplifying a great book and a great thesis, but it comes down to gamifying a task and pushing yourself right up to your limit to abstract the tedium away from work and feel a sense of accomplishment.

“No no, make sure the power tie is hanging outside of the coat.” -1980s

This also seemed like a positive revelation. Here was an algorithm for work. A way to spread the limited energy left to a single day even further.

The last book was what tied the two disparaging concepts together for me. Getting Things Done: The Art of Stress-Free Productivity is a different sort of book entirely. It’s best described as a productivity formula for the 1980’s power-tie-wearing business person. Most of the concepts are a little dated for the modern workflow, but they can be hammered to fit. However, to me this is a code cookbook. Here is a way a person can apply these concepts of picking new habits, gamifying work, and understanding the underlying principles of doing work to build a system.

In the end these made me feel, at least, like I had the sort of high level understanding of what was going on inside my head. Why did I enjoy some tasks more than others? Why was I more organized and not less on vacations? How does a productive person schedule their day? All these combined into the start of my ability to get real control over my work habits.

I’m far from a master, but I’m making measurable progress. I’m interested to see if any of the readers have had similar revelations or book recommendations.

Filed under: Hackaday Columns, Interest, lifehacks

Pulley Lamp Stands Up With You

ศุกร์, 10/14/2016 - 22:31

Standing desks are either the best thing since sliced bread, or the fastest way to make your legs tired and get you ridiculed by your coworkers in the bargain. This leads some folks to compromise and make standing desks that can be re-lowered to sitting height when you need to take a break. But now the distance from your desktop to the light source that illuminates it has changed. We can’t have that!

[John Culbertson] came up with a very elegant solution to the “problem”. He made lights that are suspended on pulleys that raise and lower with the desk itself. We’re not sure that you’re in the same situation he is, but we’re sure that you’ll agree that he did a nice job.

Besides the pulley mechanism, the light shades are a work of art. [John] clearly wanted a retro feel, so he used low-voltage lightbulbs, but augmented them with LED strips to pump out the lumens. All in all, there’s a tremendous attention to detail in the project, and it shows.

Disclaimer: your humble author is writing you this missive from a standing desk. Ours is just a regular desk put up on bricks — a temporary solution that’s become permanent. We’re always keeping our eyes out for mechanisms to make the desk convertible, but everything that we’ve seen is either overkill or ridiculously overpriced or both. It’s hard to beat 24 bricks at $0.35 apiece. Anyone have any suggestions?

Of course, with an adjustable desk come the problems of moving your lighting along with it, but [John] has solved that one for us.

Filed under: home hacks

Li-Ion Tech Staring Into the Abyss with Note 7 Failure

ศุกร์, 10/14/2016 - 21:01

Unless you’ve been living under a high voltage transformer, you’ve heard about the potential for Samsung’s latest phone, the Note7, to turn into a little pocket grenade without warning. With over 2.5 million devices in existence, it’s creating quite a headache for the company and its consumers.

They quickly tied the problem to faulty Li-ion batteries and started replacing them, while issuing a firmware update to stop charging at 60 percent capacity. But after 5 of the replacement phones caught fire, Samsung killed the Note7 completely. There is now a Total Recall on all Note7 phones and they are no longer for sale.  If you have one, you are to turn it off immediately. And don’t even think about strapping it into a VR headset — Oculus no longer supports it. If needed, Samsung will even send you a fireproof box and safety gloves to return it.

Every airline has been broadcasting warnings not to power on or charge a Note 7 on a plane. Image Source: CNET

It should be noted that the problem only affects 0.01% of the phones out there, so they’re not exactly going to set the world on fire. However, it has generated yet another discussion about the safety of Li-ion battery technology.

It was just a few months ago we all heard about those hoverboards that would catch fire. Those questionably-engineered (and poorly-named) toys used Li-ion batteries as well, and they were the source of the fire problem. In the wake of this you would think all companies manufacturing products with Li-ion batteries in them would be extra careful. And Samsung is no upstart in the electronics industry — this should be a solved problem for them.

Why has this happened? What is the deal with Li-ion batteries? Join me after the break to answer these questions.


No, we’re not talking about the song from Nirvana. We’re talking about something much cooler —  the third element in the periodic table! Lithium is part of the alkali metals group. All elements in the group have a single valence electron, which it loses easily. This makes elements in this group highly reactive. When a lithium atom loses an electron, the atom becomes a positively charged ion.

Check out what happens when you drop pure lithium into water. The electrons get stripped from the lithium atoms and causes the water to undergo electrolysis. It breaks in to H and OH groups, with the OH groups having a negative charge. This causes an ionic bond with the positive lithium ions to form lithium hydroxide, and the leftover H’s bonds together, eventually making hydrogen gas. The lithium hydroxide is soluble in water, and immediately breaks back into ions.

Long story short — lithium is highly reactive because it loses electrons so easily and forms positive ions. And this comes in handy when we want to make electrical current!

The Lithium Ion Battery BGR reported on this crispy Note 7 back in the first week of September

Using lithium for a battery is a no-brainer. You can find lithium ion batteries almost everywhere these days. From phones to laptops to tablets… even electric cars. The batteries work similar to a basic lead-acid battery, but have a much higher energy density.

They’re constructed by making many layers of cathode/anode pairs, with the cathode being a lithium metal oxide and the anode being graphite. The electrolyte is a lithium salt dissolved in an organic solvent. Each cathode/anode layer is separated by what is known as a separator.

The electrolyte carries the lithium ions through the separator between the anode and cathode. The separator is a permeable membrane that allows the tiny ions to pass, while keeping the anode and cathode physically separated. During charging, the lithium ions move from the lithium metal cathode, pass through the separator and are stored in the graphite anode.  During discharge, the ions move back to the cathode.

The Problem

Now that we have a basic idea of how lithium ion batteries work, we can begin to understand how they can fail.

The biggest fail point is obviously the separator. If a problem occurs with the separator, allowing the anode and cathode to touch, bad things will happen. Add to this the fact that the electrolyte is an organic solvent (most organic solvents are flammable) and you’ve got trouble.

Watch what happens when [JerryRigEverything] starts poking around the insides of a Note 7 battery. To be fair, he would get the same result with any Li-ion battery. However, you see as he pokes holes through the membranes, massive current flow takes place and ignites the organic solvent. And there is little one can do to stop it. It is inherent to Li-ion batteries.

In regards to the Note 7, it would appear that they pushed Li-ion technology too far by trying to cram as much energy as they could into a small space. Samsung reported a manufacturing error that “placed pressure on plates contained within battery cells, which brought negative and positive poles into contact.”

The Solution

One glaring oversight is that the battery in the Note 7 is not consumer replaceable. Imagine how easy the fix would be just to send everyone new batteries and set up a collection process for the old ones. Instead, Samsung now needs to recycle all components in the entire phone… 2.5 million times.

More industry-changing solutions include using safer forms of lithium derivatives, such as lithium iron phosphate. LFP batteries have a 14% lower energy density than typical Li-ion batteries, but are much safer. The oxygen atoms in the cathode are much harder to remove, giving it better thermal and chemical stability. Another interesting note, not safety related, is that they discharge at a constant 3.2 volts, reducing the need for energy hungry voltage regulators.

But the consumer phone market is a blood-sport, and battery life is usually the number one complaint of Android phone users. To reduce your energy density for a safer battery is a very hard sell for an engineering team to make. Well, it used to be a hard sell for the engineers — this incident should turn that around. But again, we thought the same about the hoverboards.

The ultimate solution begs for a major breakthrough. This can come from one of two sides: revolutionary battery technology that breaks through the power density ceiling while reducing the risk of a chemical catastrophe in your pocket, or orders-of-magnitude power draw reductions that would eliminate the need to carry around so darn much Lithium in a such a small package.


The main image is of one of the earliest reports, a posting on Baidu from August 24th, 2016.

Filed under: Cellphone Hacks, chemistry hacks, Current Events, Featured, news

Maslow Brings The Wall Plotter Into The Woodshop

ศุกร์, 10/14/2016 - 18:00

Hanging plotters, or two steppers controlling a dangling Sharpie marker on an XY plane, are nothing new to our community. But have you ever thought of trading out the Sharpie for a wood router bit and cutting through reasonably thick plywood sheets? That would give you a CNC machine capable of cutting out wood in essentially whatever dimensions you’d like, at reasonably low-cost. And that’s the idea behind [Bar]’s Maslow. It’s going to be a commercial product (we hope!), but it’s also entirely open source and indubitably DIYable.

[Bar] walks us through all of the design decisions in this video, which is a must-watch if you’re planning on building one of these yourself. Basically, [Bar] starts out like any of us would: waaaay over-engineering the thing. He starts out with a counterweight consisting of many bricks, heavy-duty roller chain, and the requisite ultra-beefy motors to haul that all around. At some point, he realized that there was actually very little sideways force placed on a sharp router bit turning very quickly. This freed up a lot of the design.

His current design only uses two bricks for counterweights, uses lighter chains, and seems to get the job done. There’s a bit of wobble in the pendulum, which he admits that he’s adjusted for in software. Motors with built-in encoders and gearing take care of positioning accurately. We haven’t dug deeply enough to see if there’s a mechanism to control the router’s plunge, which would be great to cut non-continuous lines, but first things first.

Taking the wall plotter into the woodshop is a brilliant idea, but we’re sure that there’s 99% perspiration in this design too. Thanks [Bar] for making it open! Best of luck with the Kickstarter. And thanks to [Darren] for the tip.

Filed under: cnc hacks

Running LISP on an ESP8266

ศุกร์, 10/14/2016 - 15:01

LISP is a polarizing language. Either you love it or you hate it. But we’ll put aside our personal preferences to bring you a good hack. In this case a LISP environment running on an ESP8266. [Dmitry] is on the “love it” side of the fence — he’s been waiting for an excuse to code up a LISP interpreter for a while, and he found one in the ESP8266.

Actually, [Dmitry] is running LISP inside JavaScript, which is itself presumably coded up in C, before it’s assembled to run on an ESP8266. (It’s turtles all the way down!) This means that he can piggy-back on JavaScript’s garbage collection and console handling and so on. After picking a suitably small LISP implementation (actually a Scheme dialect for those of you who know the difference), he went to work.

One weekend bled into the next, but he got the system running, connected to the network, and had LEDs blinking! In the end, he even managed to squeeze in some optimization for memory’s sake. Pretty cool, and because it takes advantage of an already complete system, it can even be made pretty useful. Not bad for a few weekends’ work!

And finally, if Lots of Irritating Silly Parentheses is your idea of a good time, but the wealth of computing resources available on an ESP8266 seem overkill, have a look at Microlisp, running on an AVR. Or go to the opposite extreme, and run a LISP OS on a Raspberry Pi. Whatever you do, don’t forget to close your parentheses! (We’re told that’s a traditional LISPer farewell.)

Filed under: Microcontrollers

Hackaday Prize Entry: A Cheap, Portable Incubator

ศุกร์, 10/14/2016 - 12:00

Millions of premature babies are born every year, and more than a few of these births occur hours away from any hospital with a NICU. [Manoj]’s entry for the Hackaday Prize is a simple, but very useful primitive incubator. Is it as good as the incubators you would find in a world-class hospital? No, but that’s not the point. This is an incubator for the rest of the world, where neonatal care is lacking.

You’re not going to get mechanical respiration or even oxygen into a device that is meant for the most far-flung areas on the planet, so this incubator focuses almost solely on monitoring. Packed inside a premie-sized sleeping bag is enough electronics to measure heart rate, blood oxygen, temperature and respiration. Also, there are a few resistive fabric elements to turn electricity into warmth.

Of course, anything you would find in any hospital or clinic would greatly outclass what this project has to offer. That’s really not the point, though; this incubator is cheap, can be deployed anywhere, and provides enough information to hopefully keep a preterm child alive. That’s good enough for us, and makes for a great entry into the Hackaday Prize.

The HackadayPrize2016 is Sponsored by:
Filed under: The Hackaday Prize

Pneumatic Launcher Gets Ham Antennas Hanging High

ศุกร์, 10/14/2016 - 09:00

Amateur radio is an eclectic hobby, to say the least. RF propagation, electrical engineering, antenna theory – those are the basics for the Ham skillset. But pneumatics? Even that could come in handy for hanging up antennas, which is what this compressed-air cannon is designed to do.

[KA8VIT]’s build will be familiar to any air cannon aficionado. Built from 2″ Schedule 40 PVC, the reservoir is connected to the short barrel by a quarter-turn ball valve. Charging is accomplished through a Schrader valve with a cheap little tire inflator, and the projectile is a tennis ball weighted with a handful of pennies stuffed through a slit. Lofting an antenna with this rig is as simple as attaching a fishing line to the ball and using that to pull successively larger lines until you can pull the antenna itself. [KA8VIT] could only muster about 55 PSI and a 70′ throw for the first attempt shown below, but a later attempt with a bigger compressor got him over 100 feet. We’d guess that a bigger ball valve might get even more bang for the buck by dumping as much air as quickly as possible into the chamber.

Looking to launch a tennis ball for non-Ham reasons? We’ve got you covered whether you want to power it with butane or carbon dioxide.

Filed under: misc hacks

Keep Tabs on the Weather with rpi_status

ศุกร์, 10/14/2016 - 06:00

[Facelessloser] is interested in glanceable information. Glancable devices are things like your car’s dashboard, your wristwatch, or widgets on a smartphone lockscreen. The glanceable information distribution system in this case is rpi_status, [facelessloser’s] entry in the Enlightened Raspberry Pi Contest.

[Facelessloser] coupled a ring of eight WS2812 RGB LEDs with a small OLED screen managed by a the common ssd1306 controller. Since he was rolling his own board for this project, [faceless] some buttons and a BMP180 temperature sensor. Going with popular parts like this meant libraries like the Pimoroni unicorn hat library for the WS2812 were readily available.

A simple display like this can show just about anything – from status of a nightly software build, to traffic along your morning commute. [Facelessloser] is using it for weather data. His data source is Weather Underground’s API. Weather information is displayed on the OLED. The WS2812’s display the temperature. A single blue light means cold. The ring fills as the temperature warms up. After eight degrees of blue, the color changes to orange, followed by red.

Check out the video after the break for a short demo of the board.

Pave the path to learning and win prizes:

Enter the Enlightened Raspberry Pi Contest!

Just teach us a how to do something awesome with a Pi. (See more entries)

Filed under: Raspberry Pi

Watch The Diesel Effect in Ballistic Gelatin

ศุกร์, 10/14/2016 - 03:01

A striking video appears to demonstrate an explosion via the diesel effect in clear ballistic gel. The diesel effect or “dieseling” refers to when a substance ignites from the effects of pressure, and it’s the operating principle behind the gadgets known as Fire Sticks or Fire Pistons.

Ballistic gel is a broad term referring to a large chunk of dense gel generally used in firearms-related testing to reliably and consistently measure things like bullet deformation, fragmentation, and impact. It’s tough, elastic, and in many ways resembles a gigantic gummi bear. Fans of Mythbusters (or certain DIY railguns) will recognize the stuff. Water-based blocks made with natural gelatin can be easily made at home, but end up with a yellow-brown color and have a limited shelf life due to evaporation. Clear blocks exist that are oil-based and don’t dry out like the water-based ones. It’s one of these that is in the embedded animation below.

Slow motion video capture is a natural companion to just about anything that you’d need ballistic gel for, and good thing — because the video captured what appears to be a diesel effect! The block is hit with a bullet, and as the bullet rapidly expands and dumps its energy into the gel, a cavity expands rapidly. During this process, some of the (oil-based) material in the cavity has been vaporized. After the expanded bullet exits (to the right of the gif above but easier to see in the video below), the cavity in the block begins to collapse. The resulting pressure increase appears to ignite the vaporized material, which explodes with a flash followed by some exhaust.

This effect has been observed in ballistic gel before, but this video shows a particularly clear ignition, followed by a secondary expansion of the cavity, then a flatulent-ish ejection of exhaust as the cavity collapses. If nothing else, it’s a very striking effect clearly captured on film. Slow-motion capture of destructive forces makes visible many things that would otherwise happen too quickly to perceive.

[via TheFirearmBlog]

Filed under: misc hacks

3D Printed Nozzles Turbocharge Microsphere Production

ศุกร์, 10/14/2016 - 01:31

Researchers at MIT have used 3D printing to open the door to low-cost, scalable, and consistent generation of microencapsulated particles, at a fraction of the time and cost usually required. Microencapsulation is the process of encasing particles of one material (a core) within another material (a shell) and has applications in pharmaceuticals, self-healing materials, and dye-based solar cells, among others. But the main problem with the process was that it was that it was slow and didn’t scale, and it was therefore expensive and limited to high-value applications only. With some smart design and stereolithography (SLA) 3D printing, that changed. The researchers are not 3D printing these just because they can; they are printing the arrays because it’s the only way they can be made.

A standard manufacturing process for microspheres is coaxial electrospraying, where electrostatic forces and a specialized nozzle are used to encapsulate particles as they emerge from an aperture. Unfortunately, current methods have very low throughput because they have only one emitter, and must choose between low flow rate, or consistent particle size.

The researchers developed a method using a 3D printed array that is not only scalable, but consistent in output. 3D printing was needed to make the complex network of channels required for uniform operation, all at a fraction of the usual cost and fabrication time involved in testing and developing such devices.

Streams of encapsulated microspheres – each about 25 micrometers in diameter – being emitted from an array of nozzles, illuminated for the picture. Electrostatic forces drive the liquid’s movement. On the right, red is used to show the helical channel of the “shell” liquid inside the nozzle.

No mention of which SLA printer was used, but the detailed report says “The devices were fabricated using a high-resolution SLA printer (pixelation ∼25 μm) with a layer height equal to 25 μm and absolute tolerances in the x–y and z directions equal to 50 μm and 125 μm, respectively” and that the printed material is an opaque green. Do those specs sound familiar to anyone?

Filed under: 3d Printer hacks