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Hackaday Links: March 22, 2020

Within the span of just two months, our world of unimaginable plenty and ready access to goods manufactured across the globe has been transformed into one where the bare essentials of life are hard to find at any price. The people on the frontline of the battle against COVID-19 are suffering supply chain pinches too, often at great risk to their health. Lack of proper personal protective equipment (PPE), especially face masks, is an acute problem, and the shortage will only exacerbate the problem as healthcare workers go down for the count. Factories are gearing up to make more masks, but in the meantime, the maker and hacker community can pitch in. FreeSewing, an open-source repository of sewing patterns, has a pattern for a simple face mask called the Fu that can be made quickly by an experienced threadworker. Efficacy of the masks made with that pattern will vary based on the materials used, obviously; a slightly less ad hoc effort is the 100 Million Mask Challenge, where volunteers are given a pattern and enough lab-tested materials to make 100 face masks. If you know how to sew, getting involved might make a difference.

As people around the world wrap their heads around the new normal of social distancing and the loss of human contact, there’s been an understandable spike in interest in amateur radio. QRZ.com reports that the FCC has recorded an uptick in the number of amateur radio licenses issued since the COVID-19 outbreak, and license test prep site HamRadioPrep.com has been swamped by new users seeking to prepare for taking the test. As we’ve discussed, the barrier for entry to ham radio is normally very low, both in terms of getting your license and getting the minimal equipment needed to get on the air. One hurdle aspiring hams might face is the cancellation of so-called VE testing, where Volunteer Examiners administer the written tests needed for each license class. Finding a face-to-face VE testing session now might be hard, but the VEs are likely to find a way to adapt. After all, hams were social distancing before social distancing was cool.

The list of public events that have been postponed or outright canceled by this pandemic is long indeed, with pretty much everything expected to draw more than a handful of people put into limbo. The hacking world is not immune, of course, with many high-profile events scuttled. But we hackers are a resourceful bunch, and the 10th annual Open Source Hardware Summit managed to go off on schedule as a virtual meeting last week. You can watch the nearly eight-hour livestream while you’re self-isolating. We’re confident that other conferences will go virtual in the near-term too rather than cancel outright.

And finally, if you’re sick of pandemic news and just want some escapist engineering eye candy, you could do worse than checking out what it takes to make a DSLR camera waterproof. We’ve honestly always numbered cameras as among the very least waterproof devices, but it turns out that photojournalists and filmmakers are pretty rough on their gear and expect it to keep working even so. The story here focuses (sorry) on Olympus cameras and lenses, which you’ll note that Takasu-san only ever refers to as “splash-proof”, and the complex system of O-rings and seals needed to keep water away from their innards. For our money, the best part was learning that lenses that have to change their internal volume, like zoom lenses, need to be vented so that air can move in and out. The engineering needed to keep water out of a vented system like that is pretty impressive.

A NES Motherboard For The Open Source Generation

As the original hardware from the golden era of 8-bit computer gaming becomes a bit long in the tooth, keeping it alive has become something of a concern for enthusiasts. There have been a succession of remanufactured parts for many of the major platforms of the day, and now thanks to [Redherring32] it’s the turn of the NES console.

The OpenTendo is a completely open-source replacement for an original front-loading Nintendo Entertainment System motherboard, using both original or after-market Nintendo CPU and PPU chips, and other still readily available components. It doesn’t incorporate Nintendo’s CIC lockout chip — Drew Littrell wrote a great article on how that security feature worked — but if you really need the authenticity there is also the NullCIC project that can simulate that component.

It’s an interesting exercise in reverse engineering as well as a chance to look at the NES at the chip level. Also for Nintendo-heads, it provides all the component footprints and schematic items in KiCAD format. Will many be built? Given that the NES was the best-selling console of its time there should be no shortage of originals to be found, but that in no way invalidates the effort put into this project. There will be NES consoles somewhere running for decades to come because of work such as this, simply remember that you don’t need to blow in the slot to make it work!

New Part Day: Battery-Less NFC E-Paper Display

Waveshare, known for e-ink components aimed at hobbyists among other cool parts, has recently released a very interesting addition to their product line. This is an enclosed e-ink display which gets updated over a wireless NFC connection. By that description, nothing head-turning, but the kicker is that there is no battery inside the device at all, as it harvests the energy needed from the wireless communication itself.

Just like wireless induction charging in certain smartphones, the communication waves involved in NFC can generate a small current when passing through a coil, located on this device’s PCB. Since microcontrollers and e-ink displays consume a very small amount of current compared to other components such as a backlit LCD or OLED display, this harvested passive energy is enough to allow the display to update. And because e-paper requires no power at all to retain its image, once the connection is ended, no further battery backup is needed.

The innovation here doesn’t come from Waveshare however, as in 2013 Intel had already demoed a very similar device to promising results. There’s some more details about the project, but it never left the proof of concept stage despite being awarded two best paper awards. We wonder why it hadn’t been made into a commercial product for 5 years, but we’re glad it’s finally here for us to tinker with it.

E-paper is notorious for having very low refresh rates when compared to more conventional screens, much more so when driven in this method, but there are ways to speed them up a bit. Nevertheless, even when used as designed, they’re perfectly suited for being used in clocks which are easy on the eyes without a glaring backlight.

[Thanks Steveww for the tip!]

Coronavirus And Folding@Home; More On How Your Computer Helps Medical Research

On Wednesday morning we asked the Hackaday community to donate their extra computer cycles for Coronavirus research. On Thursday morning the number of people contributing to Team Hackaday had doubled, and on Friday it had doubled again. Thank you for putting those computers to work in pursuit of drug therapies for COVID-19.

I’m writing today for two reasons, we want to keep up this trend, and also answer some of the most common questions out there. Folding@Home (FAH) is an initiative that simulates proteins associated with several diseases, searching for indicators that will help medical researchers identify treatments. These are complex problems and your efforts right now are incredibly important to finding treatments faster. FAH loads the research pipeline, generating a data set that researchers can then follow in every step of the process, from identifying which chemical compounds may be effective and how to deliver them, to testing they hypothesis and moving toward human trials.

Continue reading “Coronavirus And Folding@Home; More On How Your Computer Helps Medical Research”

Motorized LEGO Train Gets Qi Charging In The Track

This project started, as many do, with a simple idea. [Ben Hoad] just wanted to take a static LEGO Hogwarts Express train kit and make it motorized. It was compatible with standard LEGO track pieces, so all he should have to do was figure out how to shoehorn a motor in there and be done with it. Right?

Well, you already know how things like this go. It started with adding the motor, which ended up being relatively straightforward once [Ben] used some community LEGO CAD tools to figure out which kits had the specific parts he needed to redesign the train in such a way that he’d have enough space inside for the motor without ruining the way it looked. But then the feature creep kicked in, and he found himself falling down that familiar rabbit hole.

A 3D representation of the train’s internal components.

The first problem was how to reliably power the train. It turns out the rear car was more or less empty already, so that became home for two 18650 batteries (the project details say “16850” but we believe that is merely a typo). [Ben] didn’t want to have to take the thing apart every time it ran down, so he wondered if it would be possible to add wireless charging.

A Qi coil in the bottom of the train car and one in a specially designed section of track got the power flowing, but getting them lined up proved a bit finicky. So he added a Hall effect sensor to the car and a strong magnet to the track, so the train would know when the coils were lined up and automatically pump the brakes.

So now he had a motorized train that could recharge itself, but how should he turn it on and off? Well, with an ESP8266 along for the ride, he figured it would be easy to add WiFi control. With a bit of code and the Homebridge project, he was able to get the train to appear as a smart switch to Apple’s HomeKit. That allows him to start and stop the train from his smartphone, complete with a routine that returns the train to the charging station once it’s finished making the rounds. [Ben] says the next steps are to put some sanity checks in, such as shutting the motors down if the train hasn’t passed the charging station in a few minutes; a sure sign that it’s not actually moving.

All [Ben] needs to do now is implement automatic LEGO train decoupling before the plastic Hogwarts students come back from spring break.

Bee Counter Will Have You Up To Your Nectar In Hive Data

While we admit that free honey sounds pretty good, beekeeping is not some set-it-and-forget-it hobby where you can just put bees in a box and come back in a month to collect the goods. With the world’s bee population in decline, it’s more important than ever to monitor the health of hives.

One way to do that is to count the bees as they leave and reenter the hive. You can use the data to determine how many workers are working, or to compare activity between multiple hives. If you notice the bees are gone for longer and longer periods, it’s probably because their nearby nectar sources are dwindling and they have to travel farther to find flowers.

This open-source bee counter built by [hydronics2] is designed to fit the opening of a standard hive. The bees can only buzz themselves back in by flying through one of 24 little IR break-beam gates. Our favorite thing about this build is the way [hydronics2] created the individual gates by sandwiching two boards together with headers as spacers. It’s such a simple and perfect solution.

It’s also pretty cool that the board is designed to be compatible with any Feather or ItsyBitsy board, so there are a lot of options for data handling. Check out the brief demo we planted after the break, and stick around for the build video. If you’d prefer a more hands-off approach, try computer vision.

Continue reading “Bee Counter Will Have You Up To Your Nectar In Hive Data”

High Power LoRa And Tropospheric Reflection Experiments

We’re used to LoRa as a free-to-use digital radio protocol allowing not-very-high data rate communications over distances of a few miles. It’s made all kinds of distributed sensor systems a breeze, and some experimenters have made an art of achieving communication over hundreds of miles. But what would happen if you took a brute-force approach to LoRa and simply wound up the power?

In a bid to test its efficiency at bouncing off the troposphere in normal conditions, [Inductive Twig] hooked up a HamShield 70cm LoRa shield to an 80W power amplifier and a high-gain Yagi antenna pointing directly upwards mounted with ingenuity on a spade, and drove around looking at the received result. With an effective radiated power of 1500W this wasn’t your normal LoRa, instead being operated with LoRa as an amateur radio mode.

For those not familiar with radio propagation, radio waves bounce off some surprising things. In this case the aim was to bounce them off the troposphere, but while radio amateurs and LoRa distance chasers wait until weather conditions deliver a so-called “lift” in which the troposphere is especially reflective, here the experiment was performed under normal flat conditions. The result characterizes LoRa’s possibilities for everyday extreme-range mode rather than chasing records, and in that there were some interesting results. The reflected signal was receivable in bursts with low but consistent signal strength, with the limiting factor during the test as that they ran out of land upon which to drive in the southernmost peninsula of New Jersey. We’ve heard of War-Driving for open WiFi… does this car dashboard setup count as LoRa-Driving?

LoRa is designed as a protocol tolerant of low signal levels and some packet loss, so this experiment is an interesting demonstration of its possibilities when used at higher powers under a licensed transmission. It shouldn’t be possible to use the 70cm band for reliable tropospheric propagation under non-lift conditions, but this shows that it can be done. Meanwhile, take a look at a previous attempt to push LoRa using a balloon.