Shared posts

05 Jul 13:36

Enginursday: Interns and Engineering

by Humsini Acharya

Hello from SparkFun’s most junior noob: the intern. That’s right, SparkFun has an internship program, and I’ve been given free rein with an Enginursday post. For those of you (including my parents) who are curious as to what exactly a Product Development Internship at SparkFun is and who I am, read on. If you just want to hear about the projects I’m working on, skip the next several paragraphs.


Hello, my name is Humsini, and I’m a senior at CU Boulder, where I study mechanical engineering and neuroscience. I’ve had the great fortune to work on a number of hands-on projects, ranging from tabletop Guitar Hero to a fingertip sensor for a neural-integrated prosthetic (which, coincidentally, was from the same lab that SparkX collaborated with for their fingertip sensor). I also do a lot of work with Engineers Without Borders, a non-profit group of student and professional engineers that develop sustainable engineering projects to meet basic human needs and empower communities.

Now I’m interning at SparkFun, which, for someone who previously turned into a real-life “The Scream” when dealing with circuits and electronics, has been quite the learning curve.

The internship, much like SparkFun itself, is hard to explain. It mainly involves a lot of coffee runs (just kidding), human target practice for Michelle’s NERF gun skills (wish I was kidding), and shadowing the various departments that work tirelessly for you – everything from product dev, to supply chain, to engineering, to shipping and receiving.

We also get to work on various projects that need help, from vetting products, to programming the Inventor’s Kit robots to draw shapes, to LilyPad wearable projects. The best part? An assignment to build our own personal project that can be whatever the heck we want. It’s sufficient to say that I have already learned A LOT so far, especially for someone coming from a non-electrical or CS background. But more details on that later…

That being said, here’s a look into some of the projects I’ve been up to:


Tasked with showing the wide range of possibilities available to teachers with the SIK, Jackson (the other Product Dev intern) and I set about creating a modified version of the autonomous robot from the SIK Experiment Guide. With some simple code and buttons to activate different modes, the robot could draw a circle, square and spirograph. While not terribly hard to code, we found the quality of the shapes varied drastically depending on where, and how well, the Sharpie was mounted to the robot. If you’re ever looking for a simple project that kids would enjoy, challenge them to make a DrawBot!

DrawBot Prototypes DrawBot Prototypes
Our DrawBot prototype, plus scribbles. Spot the difference: the DrawBot vs. Nux's car from Mad Max: Fury Road

Turntable Teardown

I acquired this beauty for $5 from the SparkFun garage sale, with the disclaimer that the volume knob was broken. Filled with all the unfettered optimism of someone who has no idea what they’re doing, I thought I could fix said knob using my highly-adept mechanical engineering skills (i.e. just jamming it in until it stuck there). After that didn’t work, I just decided to take it apart instead.

The Turntable The Turntable
The turntable The turntable, now open

Side rant: The funniest part of working on hands-on projects, for me, is that no matter how much theory you know, something can still sideline you in the simplest of ways. Have I taken an entire class on the mind-numbing intricacies of screws – mechanics, American and International standards and precision classes, various types, how to calculate the shear and bending stress surrounding them, manufacturing process, etc.? Yes. And yet, there was one dastardly screw that just barely escaped my trusty SparkFun screwdriver and made getting into this thing a 45-minute affair.

alt text

Just call me Magic Mike, because boy, did I strip that.

I managed to tear that puppy apart, and I was excited to see how all of it worked, but after taking one look at that circuit board my entire brain just made cricket noises. Toto, we’re not in voltage-resistor circuits anymore.

alt text

Never thought I’d say it, but I miss truss systems.

But that’s okay! After some quick Googling of components and how turntables work, I was able to figure it out.

alt text

Please excuse the highly professional use of MS Paint.

The circuit has two IC chips: a PT233 (an audio transformer), and an LA1824 (an FM/AM chip for circuits with manual tuning). While I am far from completely taking apart the turntable, it’s a fair start and I’m excited to take apart the inner components further.

Ideas for a Final Project

It took a a good month to figure out what I wanted to do for my personal project. What I’ve noticed about idea generation for projects is that you quickly fall down a rabbit hole and end up with more ideas than you could possible have the time for.

3D Brain

Because I’m huge nerd for neuroscience, I decided on 3D printing a brain with clear PLA, then implanting LEDs in the different lobes to light up with different buttons. If I’m feeling extra frisky, I might even use some 3mm EL wire to demonstrate some basic sensory circuits. This, however, is still mostly in the idea phase: neural circuits are hard enough to viusalize in in two dimensions, let alone three. I did find a great project on Thingiverse that has the same sort of look I’m shooting for.

Walking Leggings

The wearables project is what I’m most excited about. I love biomechanics and motor control, and one of the most fascinating concepts is bipedal walking – everything from the overall inverse pendulum dynamics, to the muscle coordination, to the motor control (conscious and sub-conscious) required to maintain balance and movement amid various dynamic environments so you don’t fall on your face fascinates me. So behold, the walking leggings! I’m trying to think of a cooler name.

Using muscle sensors and fiber optic fabric, I want to light up muscle groups, overlaid on a pair of leggings, that activate as your muscles do. Increased muscle activity corresponds to increased brightness – essentially, leggings that demonstrate this.

This project excites me not only because my inner research nerd is super excited, but also because I get to experiment and prototype with sewable electronics, something I’ve never done before! Speaking of which, if anyone has ever had experience sewing fiber optic fabric, I am desperately seeking advice. The fiber optic fabric requires a 5mm LED, which while kind of bulky for a wearable, I think will create a fun opportunity to play with enclosures and possibly 3D printing on fabric (I’m imaging a kind of 3D-printed thigh holster for the LEDs).

This week I’ll also be prototyping reusable electrodes that sew into a garment using this cool tutorial from Advancer Technologies.

alt text

My notes so far on how I want to make the leggings.

After I test how feasible the DIY conductive fabric electrodes are, I will actually plan out the full circuit I want to use (possibly an I2C protocol?), but that’s next week’s problem.

Lessons Learned

Even though I’m at various stages of completion in these projects, I’ve learned a lot:

  1. Always start simple.

    Whether it’s drawing a rectangle with a little robot or protoyping a muscle sensor, starting simple enough to be able to make observations of what is and isn’t working helps with refining the product in the long term. For example, after prototyping an LED with the fiber optic fabric, I realized I needed much brighter LEDs and a much tighter enclosure if I wanted a more dramatic effect, and may even need to swap the fabric for cables instead.

  2. Learn before you leap

    No idea I’ve come up with has been completely unique. Learning about how other people have done similar projects has been invaluable in terms of feasibility, mistakes to avoid, and how to actually, well, actualize the idea.

  3. Embrace the rabbit hole

    Unless you’ve been living in a literal rabbit hole, I’m sure you’ve notice that SparkFun is full of people that make cool s**t. The hours I have spent scrolling through all the cool projects people have made - at SparkFun and on the internet - have opened my eyes to a whole new world of makers, hackers and hobbyists. I honestly can not believe some of the cool things people come up with. Whether it’s chasing ideas or learning how drivers work for your RPI LCD screen, I can tell I’ve learned a lot when I can no longer see the heading titles on all the tabs I have open.

  4. What the hell is engineering, anyway? (Alternatively: Call me a maple tree, because it’s about to get sappy.)

    My definition of what an engineer is and does keeps changing. After three years of stressing over equations and textbooks about as exciting as tax code, I forgot that engineering could actually just be fun.

    That there is a community of people just making cool things for the sake of making cool things (and sharing their process, no less) is incredibly inspiring, and really broadens the definition of engineering beyond the stuffy, erudite and exclusive image it can be. Being a year a way from the ever dreaded “real world,” I’m excited to see that engineering can take us anywhere from complex prosthetics that can initiate movement from muscle signals and give sensory feedback to the user, to sustainable water and sanitation systems that improve quality of life and health for impoverished communities, to something that just simply puts a smile on your face.

Not even to mention that SparkFun products can be used in any of those fields, providing ease-of-use and quality hardware to your various electronics projects. (Wink, wink, do I get my commission now?)

comments | comment feed

16 Jun 15:01

Magical learning

by John

I asked two questions on twitter yesterday. The previous post summarized the results for a question about books that I asked from my personal Twitter account.

This post will summarize the results of a question I asked from @AnalysisFact.

Here are the results by category. Some are not strictly theorems but rather topics or conjectures.

Computer science

  • Curry-Howard correspondence
  • P=NP or not
  • Collatz Conjecture


  • Cohen’s forcing theorem
  • Godel’s Incompleteness theorem
  • Continuum hypothesis
  • Zorn’s lemma

Algebra and number theory

  • The ABC conjecture (theorem?)
  • Prime number theorem.
  • Riemann hypothesis
  • Fundamental theorem of finite abelian groups
  • Classification of finite simple groups
  • Fermat’s last theorem, the unpublished Fermat version

Topology and differential geometry

  • Thurston’s geometrization conjecture
  • Gauss Bonnet theorem
  • de Rham’s theorem
  • Grothendieck Riemann Roch theorem


  • Banach-Tarski theorem.
  • Stokes theorem
  • Carleson-Hunt theorem
  • The epsilon/delta definition of continuity
  • Universal approximation theorem

Differential equations

  • Navier–Stokes existence and smoothness postulate
  • The relativistic version of the Shrodinger equation
  • Atiyah-Singer index theorem

Mathematical physics

  • E = mc²
  • Noether’s theorem
  • Liouville’s theorem


  • Existence of general equilibrium prices
  • Farkas’ lemma
  • The graph minor theorem
  • Central limit theorem

Mischievous genie

A couple people picked up the fact that in folk stories, being granted a wish doesn’t usually turn out well.

M. Shah: uh oh. Is this one of those malicious genies that twists language used to make the wish so that you are granted some horrific wish?

Jumpy the Hat: You now understand every single thing about irrational numbers but it’s all wasted because you’re cursed to become NJ Wildberger and you don’t think they exist

M Shah: or you want to thoroughly understand some theorem about Weierstrass’s monster. But little did anyone know that Weierstrass actually did have a pet monster. And it ends up biting your head off because it doesn’t like other things that are continuous.

27 May 15:21

An Excellent Countersink

by Will Myers

IMG_2533 (2)

My favorite countersink for wood has always been the square-drive ones used with a bit brace. They are easy to control and, when sharp, are quite fast.

I forgot to bring a countersink for a project I was working on today, and the only thing I had on hand were two that were made to cut metal. I have had them for a couple of years and use them to countersink the screws in the metal spiders on the candle stands I make, but I had not tried them on wood. Come to find out they work great in wood, too.

IMG_2536 (2)

These are available from McMaster-Carr for less than $20 each. The two I have are part numbers 2724A122 (cuts up to 7/16″) and 2724A132 (cuts up to 9/16″). These cut the cleanest countersink I have ever seen in both soft and hard woods. They also work well powered by a simple hand drill.

IMG_2538 (2)

— Will Myers


16 Mar 15:07

Artist Anne Truitt on the Transcendent Sense of “Enough” and the Epiphany That Revealed to Her the Purpose of Art

by Maria Popova

“I saw myself stretched like brown earth in furrows, open to the sky, well planted, my life as a human being complete.”

Artist have different ways of arriving at their life’s purpose. Some, like Van Gogh, illuminate it with a slow-burning fire. Others awaken to it with the jolt of an epiphany in a single moment: Virginia Woolf found hers in the garden, James Baldwin in a puddle, Patti Smith at the park pond, and Pablo Neruda by reaching his hand through the fence.

For the pioneering sculptor Anne Truitt (March 16, 1921–December 23, 2004), the revelation arrived one November day in 1961, midway through her fortieth year, when she was visiting New York with a friend for a weekend of art.

Anne Truitt in Vogue, 1968

In Daybook: The Journal of an Artist (public library) — the trove of insight that gave us Truitt on compassion, the parallels between being an artist and being a parent, and the vital difference between doing art and being an artist — she recounts a formative epiphany she had at the Guggenheim Museum:

When we rounded into the lowest semi-circular gallery, I saw my first Barnett Newman, a universe of blue paint by which I was immediately ravished. My whole self lifted into it. “Enough” was my radiant feeling — for once in my life enough space, enough color. It seemed to me that I had never before been free. Even running in a field had not given me the same airy beautitude. I would not have believed it possible had I not seen it with my own eyes. Such openness wiped out with one swoop all my puny ideas. I staggered out into the street, intoxicated with freedom, lifted into a realm I had not dreamed could be caught into existence. I was completely taken by surprise, the more so as I had only earlier that day been thinking how I felt like a plowed field, my children all born, my life laid out; I saw myself stretched like brown earth in furrows, open to the sky, well planted, my life as a human being complete.

Barnett Newman, Cathedra, 1951

But rather than a passive completeness, the revelation seeded in Truitt a transcendent restlessness out of which she wrested the next chapter of her life as an artist:

I went home early … thinking I would sleep and absorb in self-forgetfulness the fullness of the day. Instead, I stayed up almost the whole night, sitting wakeful in the middle of my bed like a frog on a lily pad. Even three baths spaced through the night failed to still my mind, and at some time during these long hours I decided, hugging myself with determined delight, to make exactly what I wanted to make. The tip of balance from the physical to the conceptual in art had set me to thinking about my life in a whole new way. What did I know, I asked myself. What did I love? What was it that meant the very most to me inside my very own self? The fields and trees and fences and boards and lattices of my childhood rushed across my inner eye as if borne by a great, strong wind. I saw them all, detail and panorama, and my feeling for them welled up to sweep me into the knowledge that I could make them. I knew that that was exactly what I was going to do and how I was going to do it.

She left New York the following day to return home to Washington. First thing Monday morning, she bought the materials for the first of the thirty-seven sculptures she would make over the course of the year, which led to her first exhibition in New York the following year and became a cornerstone of her major retrospectives at the Whitney Museum and the Corcoran Gallery a decade later.

Daybook remains a remarkable read in its totality, in large part because Truitt was trained as a psychologist before she became an artist and is able to put her extraordinary powers of introspection in the service of unveiling universal insight into the creative life. Complement it with Truitt on what sustains the creative spirit, how parenting shapes our capacity for solitude, and the syncopation of grief and gladness, then revisit Teresita Fernández’s spectacular commencement address on what it really means to be an artist.

donating = loving

Bringing you (ad-free) Brain Pickings takes me hundreds of hours each month. If you find any joy and stimulation here, please consider becoming a Supporting Member with a recurring monthly donation of your choosing, between a cup of tea and a good dinner.


Brain Pickings has a free weekly newsletter. It comes out on Sundays and offers the week’s most unmissable reads. Here’s what to expect. Like? Sign up.

23 Feb 19:34

A Fake Dark Web Hitman Site is Linked to a Real Murder

by Joseph Cox

Stephen Allwine is allegedly a killer. According to a criminal complaint, Stephen is suspected of shooting his wife, Amy Allwine, in the head with a nine millimeter pistol in their Cottage Grove, Minnesota, home last year.

But one key part of the story that led prosecutors to charge Stephen was his alleged, and failed, attempt to hire a hitman on the so-called dark web to murder Amy. That site, called Besa Mafia and ostensibly run by Albanian gangsters, was an elaborate scam, and in May a hacker posted the site's customer details and messages online, as Motherboard previously reported.

The Allwines' case reveals that the FBI paid very close attention to those hacked records, and tipped off at least one potential victim—Amy.


"If you want to kill someone, or to beat the shit out of him, we are the right guys," the Besa Mafia site read. In February 2016, someone with the username "dogdaygod" approached the supposed hitmen with a job: He wanted Amy Allwine dead, and wanted to make it look like a car accident. That would cost $6,000, Besa Mafia replied.

Stephen Allwine/Washington County District Court

Dogdaygod seemed to know Amy well—the anonymous user said Amy would be traveling to Moline, Illinois in March and asked if the hit could be carried out then. After some back and forth—Besa Mafia said their hitman was caught and in police custody, delaying the job—the group solicited more money from Dogdaygod. They asked for another $12,000.

But in May, a hacker targeted the site, published Besa Mafia's customer list, and revealed the site as a fraud. Dogdaygod never got what he paid for, and instead moved onto Dream Market, a dark web marketplace, and enquired about buying scopolamine.

The drug, according to the criminal complaint, "is known to erase a person's memory, rendering them incapable of exercising their free will. The drug is made into an odorless and tasteless powder that quickly dissolves in liquids and is commonly put into drinks or sprinkled on food."

After the Besa Mafia hack, the FBI read Dogdaygod's messages, and saw the user had ordered a hit on Amy. On June 1, FBI Special Agent Silkey and Detective Raymond met with the Allwines, and had Amy go to the local police department for more information. Officers advised Amy to install new security measures in light of the threats; the couple added an alarm to the house.

Amy received more threats from an anonymous email account over the next few weeks, encouraging her to commit suicide.

"Commit suicide. If you do not, then you will slowly see things taken away from you, and each time you will know that you could have stopped it, which will eat you apart from the inside," one of the emails read.

The next month, Stephen bought the handgun that would be used to kill Amy. Throughout the day she died, Amy had complained of feeling faint, and had searched the internet for "Vertigo-Wikipedia."

Investigators found residue on Stephen's right-hand consistent with a gunshot. A medical test conducted on Amy's body found her blood contained over forty five times higher the concentration of scopolamine than would be after a normal, therapeutic dose.

What connects Stephen to the fake dark web hitman site, however, is that during a forensic examination of Stephen's devices, officers found a deleted backup file of an identical bitcoin address sent by Dogdaygod to Besa Mafia.

"This specific bitcoin wallet address is the exact same address provided by dogdaygod, thus linking Defendant directly to dogdaygod," the complaint reads.

The FBI's warning was not enough to save Amy's life. An FBI spokesperson neither confirmed nor denied it is investigating users of Besa Mafia.

Kevin DeVore, Stephen's attorney, told Motherboard that the case is still in the pretrial stage, and that a court date is scheduled for June 2.

Stephen is charged with second degree murder, was briefly released after posting a conditional bail of $500,000, but was arrested again after he tried to contact his and Amy's nine year old son, and track him with a GPS smartwatch. Stephen is banned from contacting him or Amy's parents, and faces a maximum of forty years in prison.

23 May 00:26

App note: Using a magnetic 3D sensor in a gear stick application

by DP


6 hall effect sensors effectively replaced by one 3D sensor, an application from Infineon Technologies. Link here (PDF)

A magnetic 3D sensor is well suitable for a detection of the position of the gear stick. The „State-of-the-art“ solution with up to 6 single hall switches can be replaced by one 3D sensor. The TLE493D-W1B6 has the same package dimensions as a hall switch and leads to cost and space savings.


08 Apr 06:19

Mini Caterpillar Loader #3DThursday #3DPrinting

by Pedro Ruiz

lcalcena shares:

Mini loader, uses 4 standard or high torque servos the links are joined filament 1.75

download the files on:

Every Thursday is #3dthursday here at Adafruit! The DIY 3D printing community has passion and dedication for making solid objects from digital models. Recently, we have noticed electronics projects integrated with 3D printed enclosures, brackets, and sculptures, so each Thursday we celebrate and highlight these bold pioneers!

Have you considered building a 3D project around an Arduino or other microcontroller? How about printing a bracket to mount your Raspberry Pi to the back of your HD monitor? And don’t forget the countless LED projects that are possible when you are modeling your projects in 3D!

The Adafruit Learning System has dozens of great tools to get you well on your way to creating incredible works of engineering, interactive art, and design with your 3D printer! If you’ve made a cool project that combines 3D printing and electronics, be sure to let us know, and we’ll feature it here!

24 Jan 15:55

Man Shoots Lamp

by Elliot Williams

What do you get when you mix together all of the stuff that you can get for cheap over eBay with a bit of creativity and some PVC pipe? [Austiwawa] gets a table lamp, remote-controlled by a toy gun, that turns off and falls over when you shoot it. You’ve got to watch the video below the break.

This isn’t a technical hack. Rather it’s a creative use of a bunch of easily available parts, with a little cutting here and snipping there to make it work. For instance, [Austiwawa] took a remote control sender and receiver pair straight off the rack and soldered some wires to extend the LED and fit it inside the toy gun. A relay module controls the lamp, and plugs straight into the Arduino that’s behind everything. Plug and play.

Which is not to say the lamp lacks finesse. We especially like the screw used as an end-of-travel stop for the servo motor, and the nicely fabricated servo bracket made from two Ls. And you can’t beat the fall-over-dead effect. Or can you? Seriously, though, great project [Austiwawa]!

Filed under: home hacks
06 Aug 16:29

Japan's Last A-Bomb Survivors Push to Eliminate Nuclear Weapons

by Mari Shibata

Dr. Shuntaro Hida with other conference attendees. Image: Mari Shibata

Thousands of people gathered in Hiroshima’s Peace Memorial Park on Thursday in the scorching heat, remembering with a one-minute silence those who had died 70 years ago as the world’s first atomic bomb victims. Japan’s Prime Minister Shinzo Abe said during the ceremony that as the only country to have suffered a nuclear attack, Japan had an “important mission” to promote nuclear disarmament.

But the future of that mission is being questioned by survivors who continued to live with the pain of that day for another 70 years.

A day before, the Nihon Hidankyo, Japan's only national organization for A-bomb survivors, hosted their last ever conference to bring together the Hibakusha—survivors of the atomic bombings in both Hiroshima and Nagasaki. The group’s secretary general, Terumi Tanaka, expressed fears that they will not live to see their fight for a nuclear-free world come to life.

"As we Hibakusha reach an average age of 80 this year, our efforts lobbying for survivors’ healthcare rights spanning over five decades has taken its toll,” he told Motherboard. “We are no longer able to overcome physical and mental limitations that come with old age. We need help from the younger generation to continue our legacy; if I had to pick one issue that would survive beyond my death, it would be the fight to eliminate nuclear weapons from this earth."

Nihon Hidankyo Secretary General Terumi Tanaka. Image: Mari Shibata

86-year-old Nobo Miyake—who was just 1.8km away from the epicenter of where US forces dropped the nuclear weapon on August 6, 1945—is one of the few Hibakusha who still speaks publicly as part of this fight. Having just returned from a two-week peace boat tour, he stood firmly in front of an audience of around 300 to share what he had witnessed.

“I was traveling from Hiroshima station to my mother’s house on a tram at around 8.15 that morning when I suddenly saw a bright blue light flash on the ceiling of the carriage,” he said. “I didn’t know what it was, I thought an accident had happened or something. At that point—when I was deciding whether to get off the train or not—the bomb hit the ground.”

The uranium-based bomb “Little Boy” dropped 580 metres above a T-shaped bridge at the junction of Honkawa and Motoyasu rivers, killing approximately 80,000 people instantly in the blast or from firestorms that raged after. The explosion, equal to that of 12,000-15,000 tonnes of TNT, destroyed approximately two thirds of Hiroshima’s buildings across five square miles. “I couldn’t see anything because of the smoke and ash creating radioactive black rain, so I continued to lay down on the ground,” Miyake said. “When it had drifted away, what I saw was complete destruction; no buildings were left, the town was on fire.”

“I rushed to my mother’s house as fast as I could with a burnt hand,” Miyake continued. “Thankfully it was just five minutes away from where I was and I found her alive. I headed south and carried her on my back, passing the many dead bodies floating in the river, as well as those screaming from severe burns and dehydration who resorted to drinking black water full of chemicals from the bomb. As I convinced the military to take my mother along with the others injured on a truck, she luckily survived after being treated for her wounds despite the pain that continued for years; everybody else on the vehicle could not survive the journey.”

Hibakusha attending the conference were asked to stand and make themselves known. Image: Mari Shibata

As Miyake finished his speech, he fell flat on the floor. The audience gasped, and staff rushed to help him in fear of the worst; luckily, he hadn’t fallen on his head. A couple of minutes later, he stood up and resumed his seat.

It was now Susumu Nishiyama’s turn to speak, who demanded a chair to sit on as he shared his experience in Nagasaki, where US forces dropped their second atomic bomb on August 9 at 11:02 local time, exploding about 500 metres above the ground killing more than 70,000 people.

“I was working inside a factory located 2.8km away from the epicenter when I saw a light that was like seeing a camera flash a thousand times at once,” he said. “The factory turned totally white. Glass scattered all over the floor like crumbs of sea salt. The sounds of the motors stopped. Next, all I could hear was voices from inside the factory’s air raid shelter. They screamed for medicine and bandages, as the smoke completely covered the sky over a lake of fire outside.”

An author and artist who has penned his views on nuclear-free world for decades, Nishiyama is more concerned with the future of the country he may not be a part of soon.

"The best thing I can do is to be here and hope the future generations will continue to tell our stories."

“With our government approving laws that would allow Japan’s armed forces to fight abroad for the first time since World War II last month, I am very concerned that I will not be able to see through the future of this nation that is going back to its old ways,” he said. “While we, the only people who understand the consequences of the atomic bomb, are rapidly diminishing, they are also justifying participation in conflicts. The US had to drop the nuclear weapon for the second time on my city just so that the Japanese Emperor could come to terms with the fact that he had lied to his own people about Japan’s achievements in the war; it did ultimately lead to his surrender just a week later on August 15, 1945. I don’t want such a thing to happen ever again to my country, even after my death.”

The oldest person in the room—who happened to be sitting behind me—was 98-year-old former doctor Shuntaro Hida, who had survived the Hiroshima A-bomb and extensively studied its after-effects. “I’ve been to London too! I have quite a few friends there,” he told me excitedly, with a smile that overpowered his quiet voice. “Although I would like to go back and persuade the whole world against nuclear weapons, it’s impossible for me to travel now. Although I’m worried about the future of this country following recent developments, I’m strapped into this wheelchair and communicating with people is difficult. The best thing I can do is to be here and hope the future generations will continue to tell our stories.”

Too frail to move, he greeted fellow survivors and young student activists. Smiling throughout, his enthusiasm was genuine; but a family member concerned by the amount of public attention swiftly pushed him away from the venue as the event drew to a close.

12 May 17:25

Xilinx Borrows Code For Their Own Devices

by Brian Benchoff

Back in 2012, [tmbinc] discovered a neat little undocumented feature in the Xilinx ISE: the ability to use TCP/IP instead of JTAG cables. [tmbinc] was working on an Open Hardware USB analyzer and discovered the nearly undocumented Xilinx Virtual Cable, a single ‘shift’ command that opens up a TCP connection and sends JTAG data out to another computer on the network. It’s extraordinarily useful, [tmbinc] wrote a daemon for this tool, and everything was right with the world.

Yesterday, [tmbinc] discovered the Xilinx Virtual Cable again, this time in one of Xilinx’s Github repos. The code was extraordinarily familiar, and looking closer at a few of the revisions, he saw it was very similar to code he had written three years ago.

The offending revision in the Xilinx repo is nearly identical to [tmbinc]’s Xilinx Virtual Cable Driver daemon. Variable names are the same, the variables are declared in the same order, and apart from whitespace, code conventions are the same. This is not to say someone at Xilinx stole code from [tmbinc], but if this were a computer science lab, there would be an academic disciplinary hearing. What’s worse, Xilinx plastered their copyright notice at the top of the code.

In an issue [tmbinc] raised, he said he was flattered, but clarified that his code was developed entirely from scratch. He believes the Xilinx code was derived from his own code written three years ago. Since [tmbinc]’s code was uploaded without a license, it defaulted to All Rights Reserved. This does not bode well for the Xilinx legal department.

In any event, you really, really have to wonder what Xilinx’s internal documentation looks like if a random person on the Internet can discover a barely-documented protocol, write a daemon, put it on the Internet, and have someone at Xilinx use that code.

Thanks to the anonymous tipster for sending this into the Hackaday tip jar.

Filed under: FPGA, misc hacks
10 Mar 18:55

Recycling heat from industry could reduce carbon emissions #ManufacturingMonday

by Jessica


Scientists are studying ways to use the potential of waste heat in order to reduce carbon emissions. Via

Industrial processes that require high temperatures often expel any surplus heat into the environment. While industries are fairly good at using as much of this surplus as possible, a small amount of heat is always wasted…

In a new study, published in Applied Energy, scientists from the University of Bath evaluated the opportunities for industry to recover heat, and analysed which technologies would work best.

‘A large potential was seen in opportunities for re-use on site, which is the simplest method often practiced at the moment. If you have this heat currently going into the atmosphere, and you have a demand for heat at a lower temperature elsewhere in the manufacturing process you can directly use it,’ explains Dr Jonathan Norman of the University of Bath, lead researcher on the project.

‘We also found good potential for converting heat into electricity. The advantage with this is that you don’t need to re-use the heat nearby, because electricity is easily transported, and can be used for many things,’ Norman says….

‘If we supplied electricity from the heat surplus, it wouldn’t have to be generated by a fossil fuel, and if it was used locally then it wouldn’t place more pressure on the emission-intensive national grid. Overall, through a combination of technologies, we think recycling heat would save about 2.2 mega tonnes of CO2 equivalent per year. In comparison, onshore wind generation in the UK saved about 3.5 Mt of CO2 equivalent in 2010, compared to the average emissions of the national grid’ Norman explains.

Read more.

05 Dec 01:13

You Can Now 3D Print with Metal at Home

by Derek Mead (

An action shot of the welder-powered printer, courtesy Michigan Tech

Dazzle someone with a tale of the 3D-printed future, where everyone, everywhere prints their own goods at home, and after the initial surprise that you can print anything from math tools to body parts wears off, you'll hear the same question: This is cool, but does it only print plastic?

Plastics may be the future, but they're not the perfect materials for everything we need. The holy grail of 3D printers is a model that can print a multitude of materials at once—imagine printing a working cell phone—but for now, it'd be nice to be able to print some good old-fashioned metal. Extremely costly options exist, but engineers at Michigan Technological University have developed a metal 3D printer that can be built for less than $2000.

"Metal was the last class of material that the low-cost open-source 3D printing community needed to complete their collection," Joshua Pearce, an associate professor at Michigan Tech's Open Sustainability Tech Lab and a co-author of a paper outlining the work to be published in IEEE Access, wrote in an email. "This helps us take one more step down the path to 'printing everything.'"

Metal parts are largely shaped by one of a trio of processes—casting, forging, and machining—or some combination of all three. Printing metal—that is, building a structure by fusing layer after layer of material—is more difficult than plastic largely because plastics can have lower melting points. Working with rapidly heated and cooled ABS plastic is less of an endeavor than developing a printer head that can work with molten iron. 

The welder lays down material on the 3-axis stage, via the paper

But an off-the-shelf machine that spits out clean lines of molten metal already exists: a MIG welder, which spools out a wire electrode that's melted as part of the welding process. The team developed a system for automatically controlling the arc and speed of the welder's electrode, which is laid down in beads that act as the printed layers.

Rather than moving the welder like a print head, the team developed a computer-controlled platform that moves in three axes. (The analogy that comes to mind is moving an ice cream cone under a soft-serve nozzle to build up a massive swirl.) By moving the stage under the bead laid down by the welder, the printer is able to build up layer after layer of printed metal.  

The team demonstrated the printer's viability with a water-tight cup design—which showed that the metal indeed fused together—as well as a sprocket shape. While the final results of durability tests aren't yet in, initial measurements show the team's printed products are far from flimsy.

"We haven't completed the full gauntlet of mechanical tests yet, but they are solid steel objects you are printing," Pearce said. "You would not want to print a ball and play catch, as it would certainly hurt to get hit with it."

Better yet, the design is open-source and runs on Linux-powered microcontrollers. To make things even easier, the printer adheres to RepRap self-replicating standards, which means the printer "runs on free software, has free and open hardware designs, requires no specialized training in welding and existing self-replicating rapid prototypers can print the primary custom components necessary for its fabrication," the team wrote.

"Utilizing the open-source hardware concept used in the RepRap community enabled us to develop the metal 3D printer in weeks rather than years," Pearce said. "Under this paradigm we are obligated to share our improvements back to the community."

"This is something we are happy to do because we can be assured that the global maker community is already hacking the concept and developing improvements on our design or applying the concept to other types of RepRaps," he added. "Making a technology open source simply helps it develop faster."

Instructions for the design, including a shopping list and open-source firmware for the various controllers needed, is available on Appropedia. The hope is that just about any hobbyist with a modicum of hacking experience, access to a 3D printer to print the specialized parts, and a couple grand sitting around could build the MTU team's design. Compared to commercial metal 3D printers that cost hundreds of thousands of dollars or an equally-costly 5-axis CNC machine, it's a much lower barrier to entry to creating custom, complex metal parts.

"I see three core applications: First, small businesses will finally have access to metal prototyping and small batch production of metal 3D printed products, which will radically drop costs while also likely reducing environmental impact similarly to what we have seen for plastic RepRaps," Pearce wrote. "Second, the developing world can use the printers to fabricate appropriate technology for sustainable development at extremely low costs. Finally, scientists will be able to digitally fabricate metal components of low-cost scientific equipment making 'open source labs.'"

Behold a cheaply printed sprocket. Via the paper

In the paper, the team notes that the concept isn't perfect just yet. Aside from needing to develop built-in safety features—with a full-on welder in play, it's far from a self-contained desktop system like a MakerBot—there are some practical hurdles to clear.

For one, the system can't yet print horizontal holes, which requires a method for building a "bridge" across gaps in layers. There may be a firmware solution, but it also relates to a second problem: the printer's resolution is limited by how thin the welder's wire material is. The team plans on moving to the thinnest commercially available wire, which will allow for finer details, but the design means that the precision of decisions is limited by how thin the wire material is.

The team does state that multiple metal alloys could be used with their method. One particularly interesting alloy they suggest is that of aluminum beverage cans, which are widely abundant, accessible, and offer a nice weight-to-strength ratio. Actually utilizing that aluminum stock would likely require creating a more pliable alloy, but for 3D-printing enthusiasts looking to get metal stock on the cheap without buying in bulk, it's an attractive option.

That last point offers a nice glimpse into the 3D-printed future. Today, our manufacturing is locked up in factories, where bulk shipments of raw materials are delivered, transformed, and distributed. But the hope is that a distributed manufacturing network powered by 3D printers could ultimately be more efficient.

"Many of the products we use are dominated by plastic," Pearce said. "It is easy for me to envision us moving to a society where we all have polymer RepRaps in our homes. For metals we would probably rely on a local business or community centers for the few times we needed metal components."

So instead of getting your spork shipped from China and stored in a warehouse, you print it when you need it. And instead of ordering a replace sprocket for your bike, your neighborhood metal printer could produce it with material from your local aluminum recycler. It's a fascinating concept, and one that continues to inch closer to reality.