Youngster’s ESP32 Jukebox Uses RFID To Queue Tunes

February 2, 2021 by 14 Comments

Though kids today have an incredible knack for figuring out modern phones and tablets, there’s still something to be said for offering a simple physical user interface for little hands. To that end, [Martin Hierholzer] has put together a whimsical jukebox that his two year old daughter can use to listen to her favorite songs. With just a few simple buttons, no display to read, and the ability to stop and start songs using RFID tags embedded into 3D printed figures, it’s a perfect interface for tiny humans just getting the hang of interacting with technology.

While the Raspberry Pi might have been the more obvious choice to base this project around, [Martin] decided to go the ESP32 route for improved energy efficiency. The popular microcontroller is more than powerful enough to play MP3s, and its integrated WiFi connectivity allows the player to download new tracks from the network occasionally. He added a micro SD slot to provide some mass storage, a PCM5102 I2S DAC with a PAM8403 amplifier to handle the audio side of things, and a MFRC522 RFID receiver that can pick up tags placed on the top of the player. Power is provided by parts salvaged from a USB battery bank, and everything is housed on a custom PCB.

The relatively low power requirements of the ESP32 means the jukebox can keep the party going for many hours (perhaps even days) when in active use. When the RFID token is removed and there are no songs to play, some clever coding kicks the chip into low-power mode to greatly extend the player’s standby time. [Martin] says it can sleep for months without having to be recharged, and considering some of the impressive feats of battery-sipping we’ve previously seen from the ESP32, we don’t doubt it.

Even if you don’t have any young music lovers at home, the documentation [Martin] has put together for this project is absolutely worth a look. Whether its how he configures the server side to push songs and firmware updates to the player, how he wrangled the ESP32’s Ultra-Low Power coprocessor (ULP), or the woodworking tips used to produce the charming enclosure, you’re sure to pick up a trick or two.

The children of hackers and makers always seem to get the coolest stuff, and we’re looking forward to seeing what [Martin] comes up with next. After all, kids grow up fast and pretty soon his daughter is going to need something new to entertain her.

This Isn’t Your Father’s Yellow Card

February 1, 2021 by 59 Comments

As the global vaccination effort rolls out in many countries, people will increasingly be required to provide evidence for various reasons, especially travelers. Earlier this month a coalition which includes Microsoft, the Mayo Clinic, Oracle, MITRE, and others announced an effort to establish digital vaccination records called the Vaccination Credential Initiative (VCI). This isn’t going to be a brand new thing, but rather an initiative to provide digital proof-of-vaccination to people who want it, using existing open standards:

  • Verifiable Credentials, per World Wide Web Consortium Recommendation (VC Data Model 1.0)
  • Industry standard format and security, per the Health Level Seven International (HL7) FHIR standard

In addition, the World Health Organization formed the Smart Vaccination Certificate Working Group in December. Various other countries and organizations also have technical solutions in the works or already deployed. If a consensus doesn’t form soon, we can see this quickly becoming a can of worms. Imagine having to obtain multiple certifications of your vaccination because of non-uniform requirements between countries, organizations, and/or purposes.

Older readers and international travelers may be wondering, “don’t we already have a vaccination card system?” Indeed we do: the Carte Jaune or Yellow Card. The concept of a “vaccination passport” was conceived and agreed upon at the International Sanitary Convention for Aerial Navigation in 1933. Over the years the names and diseases of interest have changed, but since 2007 it has been formally called the International Certificate of Vaccination or Prophylaxis (ICVP). In recent times, yellow fever was the only vaccination of interest to travelers, but other vaccinations or booster shots can be recorded as well. One problem with the paper Yellow Card is that it is ridiculously easy to forge. Nefarious or lazy travelers could download it from the WHO site, print it on appropriate yellow card stock, and forge a doctor’s signature. The push for a more secure ICVP is not completely unreasonable.

Reading the instructions on the Yellow Card brings up a couple of interesting points:

  • This certificate is valid only if the vaccine or prophylaxis used has been approved by the World Health Organization — Currently the Pfizer vaccine is the only one to be approved by WHO, and even that is only an emergency approval. If you receive a non-Pfizer vaccination, what then?
  • The only disease specifically designated in the International Health Regulations (2005) for which proof of vaccination or prophylaxis may be required as a condition of entry to a State Party, is yellow fever — This one is interesting, and suggests that member states cannot require proof of Covid19 vaccination as an entry requirement, a situation that will no doubt be quickly revised or ignored.

Note: This writeup is about vaccinations, not about immunity. While immunity certificates have been used from time to time throughout modern history, the concept of an international immunity passport is not well established like the ICVP.

Why Blobs Are Important, And Why You Should Care

January 29, 2021 by 53 Comments

We are extraordinarily fortunate to live at a time in which hardware with astounding capabilities can be had for only a few dollars. Systems that would once have taken an expensive pile of chips and discretes along with months of development time to assemble are now integrated onto commodity silicon. Whether it is a Linux-capable system-on-chip or a microcontroller, such peripherals as WiFi, GPUs, Bluetooth, or USB stacks now come as part of the chip, just another software library rather than a ton of extra hardware.

Beware The Blob!

An ESP-01 module
The cheapest of chips still comes with a blob.

If there is a price to be paid for this convenience, it comes in the form of the blob. A piece of pre-compiled binary software that does the hard work of talking to the hardware and which presents a unified API to the software. Whether you’re talking to the ESP32 WiFi through an Arduino library or booting a Raspberry Pi with a Linux distribution, while your code may be available or even maybe open source, the blob it relies upon to work is closed source and proprietary. This presents a challenge not only to Software Libre enthusiasts in search of a truly open source computer, but also to the rest of us because we are left reliant upon the willingness of the hardware manufacturer to update and patch their blobs.

An open-source advocate would say that the solution is easy, the manufacturers should simply make their blobs open-source. And it’s true, were all blobs open-source then the Software Libre crowd would be happy and their open-source nature would ease the generation of those updates and patches. So why don’t manufacturers release their blobs as open-source? In some cases that may well be due to a closed-source mindset of never releasing anything to the world to protect company intellectual property, but to leave it at that is not a full answer. To fully understand why that is the case it’s worth looking at how our multifunctional chips are made.

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Goodbye 2020 Contest Winners Announced

January 27, 2021 by 7 Comments

The Goodbye 2020 contest asked you to turn out the lights on an objectively crappy year in an interesting way. Four winners have been announced, and we have to tip the hat to [Becky Stern] for both creativity and execution on the 2020 candle seen above. Three wicks burn the candle down, revealing a metalwork dumpster fire along the way. It’s not just a performance piece but also an interesting look into candle making with 3D printed molds and insight on specifics like pour-temperature for best results. [Becky] entered as a group with a few other YouTube channels that included gags like [TechnoChic’s] knitted 2020 mask that is unraveled to count down the to the end.

[Marius Taciuc] spun up a clock to count down his year. The custom PCB uses a set of 7-segment displays to show the time (and some custom messages), along with a battery-backed RTC for precision. The aesthetic is a PC overclocker’s dream as the timepiece lives inside of a mason jar filled with baby oil.

You certainly can’t go out to a rave during these pandemic times. [George Cave] brought the party to his face with a set of shades that blast RGB light into your eyeballs. A pair of ultasonic distance sensors shut the party down if anyone breaks social distancing guidelines.

And [Scott Clandinin] picked up an honorable mention with a Christmas-themed countdown. A color LCD takes the place of a from/to card on a gift wrapped package, displaying the number of days using candy cane font.

Congratulations to each of the winners who received a $25 Tindie gift card for showing off their whimsical work.

Arduino Learns The Martial Arts With Nunchucks Input Device

January 26, 2021 by 11 Comments

There is a boring part of every computer introduction class that shows how a computer is made up of input, output, and processing. Maybe it wouldn’t be so boring if the input device was a nunchuck. [Brian Lough] thinks so and he belligerently asserts that nunchucks are the best input device ever. With a simple connection to a Wii controller and an associated library, you get access to an analog joystick, two buttons, and an accelerometer.

The nunchuck is meant to plug into a Wii controller and the connection is I2C, so that’s trivial to interface to an Arduino or other small microcontroller. The only issue is making the connection. We might have just snipped the wires, but [Brian] prefers to use a small breakout board that plugs into the stock connector and provides solder points for your own cable. There are options for the breakout boards, and [Brian] has his own design that you can get from OSHPark for about a buck for three boards. You can also just jam wire into the connector, but that’s not always robust.

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What’s The Deal With Chromium On Linux? Google At Odds With Package Maintainers

January 26, 2021 by 152 Comments

Linux users are more likely than most to be familiar with Chromium, Google’s the free and open source web project that serves as the basis for their wildly popular Chrome. Since the project’s inception over a decade ago, users have been able to compile the BSD licensed code into a browser that’s almost the same as the closed-source Chrome. As such, most distributions offer their own package for the browser and some even include it in the base install. Unfortunately, that may be changing soon.

A post made earlier this month to the official Chromium Blog explained that an audit had determined “third-party Chromium based browsers” were using APIs that were intended only for Google’s internal use. In response, any browser attempting to access features such as Chrome Sync with an unofficial API key would be prevented from doing so after March 15th.

To the average Chromium user, this doesn’t sound like much of a problem. In fact, you might even assume it doesn’t apply to you. The language used in the post makes it sound like Google is referring to browsers which are spun off of the Chromium codebase, and at least in part, they are. But the search giant is also using this opportunity to codify their belief that the only official Chromium builds are the ones that they provide themselves. With that simple change, anyone using a distribution-specific build of Chromium just became persona non grata.

Unhappy with the idea of giving users a semi-functional browser, the Chromium maintainers for several distributions such as Arch Linux and Fedora have said they’re considering pulling the package from their respective repositories altogether. With a Google representative confirming the change is coming regardless of community feedback, it seems likely more distributions will follow suit.

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Hackaday Links: January 17, 2021

January 17, 2021 by 16 Comments

Sad news from Mars, where the InSight lander’s “mole” was officially declared dead. The self-drilling probe, the centerpiece of the Heat Flow and Physical Properties Package (HP3) experiment, was designed to ram itself 5 meters into the Martian regolith while deploying a sensor-laden tail. The mole would then explore heat flow from within the planet. But the unexpected properties of the soil beneath the lander, including lower-than-expected friction on the hull of the mole and a cement-like “duricrust” layer, confounded the probe’s downward progress for the last two years. We covered the design of the mole, which is similar to an impact drill, as well as the valiant efforts to save the mission, but after one last try on January 9 where the mole gave 500 more whacks without any progress, controllers threw in the towel. It just goes to show that space travel and exploration are anything but routine, and that there’s far, far more we don’t know about even our nearest solar neighbor than what we do know.

Sad news, too, from closer to home, this time — Ohio, to be exact: the 2021 Hamvention has been canceled. It’s not exactly a surprise given the ongoing COVID-19 pandemic, but it’s still a blow to have ham radio’s biggest party canceled for two years running. We expect a lot of cons and meetings will suffer a similar fate in 2021. We’ll be sure to bring you any announcements we hear about.

One event that hasn’t been canceled is iQuHACK, a quantum hackathon hosted by MIT. We don’t pretend to fully understand quantum computing, or even to have scratched the surface of the subject in any meaningful way. Following up on what comes out of iQuHACK after it runs next weekend might be interesting for the quantum-curious, though. But really, just the fact that we’re in an age where quantum hackathons are a thing is pretty cool.

Back on the COVID-19 theme, managing editor Elliot Williams gave us the heads up on a story about gorillas at the San Diego Zoo Safari Park testing positive for the virus. It’s not exactly surprising that some of our evolutionarily closest relatives would be susceptible to the disease, and it’s not exactly a funny story, but the conversation in the morning meeting at the zoo must have been priceless:

“Hey, that gorilla looks sick. We’d better test him for COVID.”
“Yeah, probably. Here’s the brain-tickling swab, you go stick it up his nose.”
“Nu-uh, you stick it up his nose!”
“Nope. Hey, where’s the intern?”

And speaking of dangerous work environments, behold yet another classic of corporate safety propaganda: The Color of Danger. Like Shake Hands with Danger, this film was produced by heavy equipment manufacturer Caterpillar. But this time, instead of concentrating on the various opportunities maintaining heavy equipment presents for traumatic amputations, the subject matter is forklift safety. We’ve spent a fair number of hours in the driver’s seat of a lift truck, so we know full well how quickly things can go wrong, and this film does a great job of showing a lot of them. But what you’ve got to admire is the trick driving and stunt work that went into these vignettes; not too many people can pull off forklift drifting safely (12:30), and putting the truck in the drink without drowning was a neat trick (13:00). And of course, with any film on forklift safety, we’d be remiss not to tip our hardhat to Staplefahrer Klaus and his oft-bloodied co-workers.

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