Over the past few months we’ve heard a lot about contact tracers which are designed to inform users if they’ve potentially come into close proximity with someone who has the virus. Generally these systems have been based on smartphone applications, but there are also hardware solutions that can operate independently for those who are unable or unwilling to install the software. Which is precisely what [Tom Bensky] has implemented using an ESP32 and a USB battery bank.

The idea is simple: the software generates a unique ID which is broadcast out by the ESP32 over Bluetooth Low Energy. Appended to that ID is a code that indicates the person’s current physical condition. There’s no centralized database, each user is expected to update their device daily with any symptoms they may be experiencing. If your tracker is blinking, that means somebody has come in close enough proximity that you should look at the collected data and see how they were feeling at the time.

It’s not a perfect system, of course, as for one thing the number of people that are willing and able to flash this firmware onto a spare ESP32 and carry the thing around with them all day is going to be extremely small. This might have filled an interesting niche if we were still going to hacker and maker cons this summer, but all of those have gone virtual anyway. That said, it’s an interesting look at how a decentralized contact tracing system can be implemented cheaply and quickly.

Another detail worth taking a look at is how [Tom] handled the user experience in his firmware. In an effort to make the tracer as easy as possible to configure, he’s using the Web Bluetooth capability of Google Chrome. Just open up the local web page in your browser, and it will handle talking to the hardware for you. Even if you’re not in the market for a contract tracer, we think this is a great example for how to handle end-user configuration on the ESP32.

We’ve already looked at contact tracer APIs from Google and Apple, dedicated COVID-19 hardware tokens, and even other open source attempts at decentralized proximity tracking. It’s a lot to process, and everyone seems to have their own idea on how it should be done. In the end, the most practical solution is probably to just stay at home as much as possible.

source https://hackaday.com/2020/07/28/esp32-turned-open-source-covid-19-contact-tracer/

Over the past few months we’ve heard a lot about contact tracers which are designed to inform users if they’ve potentially come into close proximity with someone who has the virus. Generally these systems have been based on smartphone applications, but there are also hardware solutions that can operate independently for those who are unable or unwilling to install the software. Which is precisely what [Tom Bensky] has implemented using an ESP32 and a USB battery bank.

The idea is simple: the software generates a unique ID which is broadcast out by the ESP32 over Bluetooth Low Energy. Appended to that ID is a code that indicates the person’s current physical condition. There’s no centralized database, each user is expected to update their device daily with any symptoms they may be experiencing. If your tracker is blinking, that means somebody has come in close enough proximity that you should look at the collected data and see how they were feeling at the time.

It’s not a perfect system, of course, as for one thing the number of people that are willing and able to flash this firmware onto a spare ESP32 and carry the thing around with them all day is going to be extremely small. This might have filled an interesting niche if we were still going to hacker and maker cons this summer, but all of those have gone virtual anyway. That said, it’s an interesting look at how a decentralized contact tracing system can be implemented cheaply and quickly.

Another detail worth taking a look at is how [Tom] handled the user experience in his firmware. In an effort to make the tracer as easy as possible to configure, he’s using the Web Bluetooth capability of Google Chrome. Just open up the local web page in your browser, and it will handle talking to the hardware for you. Even if you’re not in the market for a contract tracer, we think this is a great example for how to handle end-user configuration on the ESP32.

We’ve already looked at contact tracer APIs from Google and Apple, dedicated COVID-19 hardware tokens, and even other open source attempts at decentralized proximity tracking. It’s a lot to process, and everyone seems to have their own idea on how it should be done. In the end, the most practical solution is probably to just stay at home as much as possible.

source https://hackaday.com/2020/07/28/esp32-turned-open-source-covid-19-contact-tracer/

Over the past few months we’ve heard a lot about contact tracers which are designed to inform users if they’ve potentially come into close proximity with someone who has the virus. Generally these systems have been based on smartphone applications, but there are also hardware solutions that can operate independently for those who are unable or unwilling to install the software. Which is precisely what [Tom Bensky] has implemented using an ESP32 and a USB battery bank.

The idea is simple: the software generates a unique ID which is broadcast out by the ESP32 over Bluetooth Low Energy. Appended to that ID is a code that indicates the person’s current physical condition. There’s no centralized database, each user is expected to update their device daily with any symptoms they may be experiencing. If your tracker is blinking, that means somebody has come in close enough proximity that you should look at the collected data and see how they were feeling at the time.

It’s not a perfect system, of course, as for one thing the number of people that are willing and able to flash this firmware onto a spare ESP32 and carry the thing around with them all day is going to be extremely small. This might have filled an interesting niche if we were still going to hacker and maker cons this summer, but all of those have gone virtual anyway. That said, it’s an interesting look at how a decentralized contact tracing system can be implemented cheaply and quickly.

Another detail worth taking a look at is how [Tom] handled the user experience in his firmware. In an effort to make the tracer as easy as possible to configure, he’s using the Web Bluetooth capability of Google Chrome. Just open up the local web page in your browser, and it will handle talking to the hardware for you. Even if you’re not in the market for a contract tracer, we think this is a great example for how to handle end-user configuration on the ESP32.

We’ve already looked at contact tracer APIs from Google and Apple, dedicated COVID-19 hardware tokens, and even other open source attempts at decentralized proximity tracking. It’s a lot to process, and everyone seems to have their own idea on how it should be done. In the end, the most practical solution is probably to just stay at home as much as possible.

source https://hackaday.com/2020/07/28/esp32-turned-open-source-covid-19-contact-tracer/

Modern smartphones are a dizzying treatise on planned obsolescence. Whether it’s batteries that can’t be removed without four hours and an array of tiny specialized tools, screens that shatter with the lightest shock, or (worst of all) software that gets borked purposefully to make the phone seem older and slower than it really is, around every corner is some excuse to go buy a new device. The truly tragic thing is that there’s often a lot of life left in these old, sometimes slightly broken, devices.

This video shows us how to turn an old smartphone into a perfectly usable laptop. The build starts with a screen and control board that has USB-C inputs, which most phones can use to output video. It’s built into a custom aluminum case with some hinges, and then attached to a battery bank and keyboard in the base of the laptop. From there, a keyboard is installed and then the old phone is fixed to the back of the screen so that the aluminum body doesn’t interfere with the WiFi signal.

If all you need is internet browsing, messaging, and basic word processing, most phones are actually capable enough to do all of this once they are free of their limited mobile UI. The genius of this build is that since the phone isn’t entombed in the laptop body, this build could easily be used to expand the capabilities of a modern, working phone as well. That’s not the only way to get a functioning laptop with parts from the junk drawer, either,  if you’d prefer to swap out the phone for something else like a Raspberry Pi.

Thanks to [NoxiousPluK] for the tip!

source https://hackaday.com/2020/07/28/broken-smartphones-laptops-in-disguise/

We take wireless devices for granted these days, and it is easy to forget that the use of the airwaves is subject to government control — the FCC in the United States. HobbyKing got a sharp reminder when the FCC levied a nearly $3 million fine for the company selling uncertified drone transmitters.

It was hardly a surprise, though. The FCC has been cracking down on these noncompliant transmitters for a while now and had issued a notice of apparent liability to the company back in 2018 and the investigation goes back to 2016. The problems included radios being sold that were on unauthorized frequencies, radios with higher than legal output power, and selling radios that were not type accepted.

Ham radio operators are allowed to buy and use radios that are not type accepted, presumably because they have the technical know-how to operate them without interference. But other types of radios do need type acceptance.

According to the FCC, “In its response to the NAL, HobbyKing did not contest that it marketed devices without equipment certifications or that it failed to respond fully to the Bureau. Instead, HobbyKing raised several unpersuasive legal challenges.”

The FCC has been after people making these transmitters, too. If you are thinking about making a transmitting device, maybe think about certification.

source https://hackaday.com/2020/07/28/fcc-fines-hobby-king-almost-3-million-for-illegal-drone-transmitters/

A few days ago, the Chinese National Space Administration launched their Tianwen-1 mission to Mars from their launch site in the province of Hainan. It should arrive at the Red Planet in April 2021, when it will face the daunting task of launching a surface probe from its orbiting component, which will release a rover once it has reached the surface. Like all such missions it’s in constant contact with its controllers on the ground, and as with any radio transmissions floating through the aether its telemetry has been received by the radio hacker community and analaysed by [r00t].

Straight away there’s something interesting in the modulation scheme, instead of a carrier with modulation applied to it there is a main unmodulated centre carrier, and the data appears instead on a series of subcarriers. Is this a feature of its being a space probe, the unmodulated carrier making it easier to find and track in deep space?

They quickly find the telemetry carrier, and decode its frames. It carries a series of data sets, including positional and instrumentation data. From the positional data they can tell when the craft has made any course changes, and from the sensor data such as the solar sensor its movement can be deduced and graphed. It makes for a fascinating insight into the mission, and we’re grateful for the analysis.

Mars is a notoriously difficult target for space probes, somewhere that multiple missions have for various reasons failed to reach. We hope the Tianwen-1 mission is ultimately successful and that in time the Chinese space people will in due course be showing us some of the fruits of their labours. They’re not alone in launching this month, so we’ve got a plethora of Mars-related stories to look forward to next year.

Header image: Tianwen-1 rover mockup. Pablo de León‎ / CC BY-SA 3.0

source https://hackaday.com/2020/07/28/what-is-the-tianwen-1-probe-saying/

If you take to the outdoors for your exercise, rather than walking the Sisyphusian stair machine, it’s nice to grab some GPS-packed electronics to quantify your workout. [Bunnie Huang] enjoys paddling the outrigger canoe through the Singapore Strait and recently figured out how to unpack and visualize GPS data from his own Garmin watch.

By now you’ve likely heard that Garmin’s systems were down due to a ransomware attack last Thursday, July 23rd. On the one hand, it’s a minor inconvenience to not be able to see your workout visualized because of the system outage. On the other hand, the services have a lot of your personal data: dates, locations, and biometrics like heart rate. [Bunnie] looked around to see if he could unpack the data stored on his Garmin watch without pledging his privacy to computers in the sky.

Obviously this isn’t [Bunnie’s] first rodeo, but in the end you don’t need to be a 1337 haxor to pull this one off. An Open Source program called GPSBabel lets you convert proprietary data formats from a hundred or so different GPS receivers into .GPX files that are then easy to work with. From there he whipped up less than 200 lines of Python to plot the GPS data on a map and display it as a webpage. The key libraries at work here are Folium which provides the pretty browsable map data, and Matplotlib to plot the data.

These IoT devices are by all accounts amazing, listening for satellite pings to show us how far and how fast we’ve gone on web-based interfaces that are sharable, searchable, and any number of other good things ending in “able”. But the flip side is that you may not be the only person seeing the data. Two years ago Strava exposed military locations because of an opt-out policy for public data sharing of exercise trackers. Now Garmin says they don’t have any indications that data was stolen in the ransomware attack, but it’s not a stretch to think there was a potential there for such a data breach. It’s nice to see there are Open Source options for those who want access to exercise analytics and visualizations without being required to first hand over the data.

source https://hackaday.com/2020/07/28/busting-gps-exercise-data-out-of-its-garmin-controlled-iot-prison/

There’s no denying that the reach and variety of internet radio is super cool. The problem is that none of the available interfaces really give the enormity of the thing the justice it deserves. We long for a more physical and satisfying interface for tuning in stations from around the globe, and [Jude] has made just the thing.

RadioGlobe lets the user tune in over 2000 stations from around the world by spinning a real globe. It works by using two absolute rotary encoders that each have a whopping 1024 positions available. One encoder is stuck into the South Pole, and it reads the lines of longitude as the user spins the globe.

The other encoder is on the left side of the globe, and reads whatever latitude is focused in the reticle. Both encoder are connected to a Raspberry Pi 4, though if you want to replicate this open-source project using the incredibly detailed instructions, he says a Raspberry Pi 3 B+ will work, too.

In the base there’s an LCD that shows the coordinates, the city, and the station ID. Other stations in the area are tune-able with the jog wheel on the base. There’s also an RGB LED that blinks red while the station is being tuned in, and turns green when it’s done. We totally dig the clean and minimalist look of this build — especially the surprise transparent bottom panel that lets you see all the guts.

There are three videos after the  break – a short demo that gives you the gist of how it works, a longer demonstration, and a nice explanation of absolute rotary encoders. Those are just the tip of the iceberg, because [Jude] kept a daily vlog of the build.

Maybe you just long for a web radio that dials in vintage appeal. This antique internet radio has a lot of features, but you wouldn’t know it from the outside.

source https://hackaday.com/2020/07/27/radioglobe-takes-the-world-of-internet-radio-for-a-spin/

For those getting started with 3D printers, thermoplastics such as ABS and PLA are the norm. For those looking to produce parts with some give, materials like Ninjaflex are most commonly chosen, using thermoplastic polyeurethane. Until recently, it hasn’t been possible to 3D print latex rubber. However, a team at Virginia Tech have managed the feat through the combination of advanced printer hardware and some serious chemistry.

The work was primarily a collaboration between [Phil Scott] and [Viswanath Meenakshisundaram]. After initial experiments to formulate a custom liquid latex failed, [Scott] looked to modify a commercially available product to suit the project. Liquid latexes are difficult to work with, with even slight alterations to the formula leading the solution to become unstable. Through the use of a molecular scaffold, it became possible to modify the liquid latex to become photocurable, and thus 3D printable using UV exposure techniques.

The printer side of things took plenty of work, too. After creating a high-resolution UV printer, [Meenakshisundaram] had to contend with the liquid latex resin scattering light, causing parts to be misshapen. To solve this, a camera was added to the system, which visualises the exposure process and self-corrects the exposure patterns to account for the scattering.

It’s an incredibly advanced project that has produced latex rubber parts with advanced geometries and impressive mechanical properties. We suspect this technology could be developed quickly in the coming years to produce custom rubber parts with significant strength. In the meantime, replicating flexible parts is still possible with available filaments on the market.

[via phys.org]

source https://hackaday.com/2020/07/27/3d-printing-latex-is-now-possible/