Servo testers are useful devices to have on hand, allowing one to quickly check a given part for proper operation. However, cheaper models can be quite limited, and may not output signals suitable for testing the full range of servos out there. [Buttim] had a few testers laying around, and wanted to see if they could be modified to do more.
Initial experiments with the cheapest model on hand came to naught, revealing nothing but a small IC with its markings scrubbed off. However, going a few more dollars upmarket, [buttim] found a servo tester packing a Nuvoton N75E003. An unfamiliar name to the hobbyist, Nuvoton microcontrollers are often found in mass-production designs due to their low cost.
The N75E003 is a 8051-based device, and [buttim] was able to source a programmer and tutorial resources on how to work with the chip. Armed with the right hardware and knowledge, the servo tester was first programmed with a basic blink sketch. With everything confirmed to be working as expected, [buttim] set about programming a custom firmware for the servo tester that would output a broader range of PWM signals to suit their needs.
It’s a great example of the learning possibilities available by simply cracking open the case of commodity hardware and diving in. Of course, if you need something even more capable, you can always build your own from scratch!
We get the idea that there’s not much chance this is going to sweep the shelves of Microsoft Office, Libre Office, and all the many competitors. However, it is a pretty stunning example of what you can do with modern HTML. There’s even a GitHub repo and a subreddit.
There’s an old tale that TV companies only need to make a few years of kids’ TV shows, because their audience constantly grows out of their offerings and is replaced by a new set with no prior knowledge of the old shows. Whether it’s true or not is up for debate, but does the same apply to single board computers aimed at kids? The original BBC micro:bit was first announced back in 2015 and must be interesting its second generation of kids by now, but that hasn’t stopped them bringing out a second version of the little educational computer. How do you update such a simple device? Time to take a look.
The form factor of the new board is substantially the same as its predecessor, with the same edge connector and large connection pads, and the familiar LED matrix display. The most obvious additions are a small speaker and MEMS microphone allowing kids to interact with audio in their code, but less obvious is a new touch button in the micro:bit logo. The original had it in the silk screen layer, while the new one has it as copper for a capacitive sensor.
The silicon has an upgrade too, now sporting a Nordic Semiconductor nRF52833 running at 64 MHz and sporting 512k of ROM and 128k of RAM with built-in Bluetooth Low Energy. Binaries are incompatible with the original, however all the development environments can recompile code for a new universal binary format capable of running the appropriate software for either version.
The micro:bit has been more of a hit in schools than it has in our community, perhaps because it has the misfortune to have arrived alongside so many strong competitors. However it remains a powerful contender whose easy programming alongside the power of more traditional toolchains make it a good choice for kids and grown-ups alike. We took a look at the original back in 2016, if you are interested.
One glimpse at the still images or the brief video below shows you exactly how [Eric Nguyen] managed to pull this off. Each segment of the display is made up of four 0.25″ (6.35 mm) steel balls, picked up and held in place by magnets behind the plain wood face of the clock. But the electromechanical complexity needed to accomplish that is the impressive part of the build. Each segment requires two servos, for a whopping 28 units plus one for the colon. Add to that the two heavy-duty servos needed to tilt the head and the four needed to lift the tray holding the steel balls, and the level of complexity is way up there. And yet, [Eric] still managed to make the interior, which is packed with a laser-cut acrylic skeleton, neat and presentable, as well he might since watching the insides work is pretty satisfying.
We love the level of craftsmanship and creativity on this build, congratulations to [Eric] on making his first Arduino build so hard to top. We’ve seen other mechanical digital displays before, but this one is really a work of art.
Modern society has brought us all kinds of wonders, including rapid intercontinental travel, easy information access, and decreased costs for most consumer goods thanks to numerous supply chains. When those supply chains break down as a result of a natural disaster or other emergency, however, the disaster’s effects can be compounded without access to necessary supplies. That’s the focus of Field Ready, a nonprofit that sets up small-scale manufacturing in places without access to supply chains, or whose access has been recently disrupted.
The challenge was met by a dream team whose members each received a $6,000 microgrant to work full time on the project. The’ve just made their report on an easier way of tracking all of the products produced, and identifying them even for those not in the organization. As a result, Field Ready has a much improved manufacturing and supply process which allows them to gather more data and get better feedback from users of their equipment. Join us after the break for a closer look at the system and to watch the team’s presentation video.
Decades ago, Einstein predicted the existence of something he didn’t believe in — black holes. Ever since then, people have been trying to get a glimpse of these collapsed stars that represent the limits of our understanding of physics.
For the last 25 years, Andrea Ghez has had her sights set on the black hole at the center of our galaxy known as Sagittarius A*, trying to conclusively prove it exists. In the early days, her proposal was dismissed entirely. Then she started getting lauded for it. Andrea earned a MacArthur Fellowship in 2008. In 2012, she was the first woman to receive the Crafoord Prize from the Royal Swedish Academy of Sciences.
Andrea Mia Ghez was born June 16th, 1965 in New York City, but grew up in the Hyde Park area of Chicago. Her love of astronomy was launched right along with Apollo program. Once she saw the moon landing, she told her parents that she wanted to be the first female astronaut. They bought her a telescope, and she’s had her eye on the stars ever since. Now Andrea visits the Keck telescopes — the world’s largest — six times a year.
Andrea was always interested in math and science growing up, and could usually be found asking big questions about the universe. She earned a BS from MIT in 1987 and a PhD from Caltech in 1992. While she was still in graduate school, she made a major discovery concerning star formation — that most stars are born with companion star. After graduating from Caltech, Andrea became a professor of physics and astronomy at UCLA so she could get access to the Keck telescope in Mauna Kea, Hawaii.
The Center of the Galaxy
Since 1995, Andrea has pointed the Keck telescopes toward the center of our galaxy, some 25,000 light years away. There’s a lot of gas and dust clouding the view, so she and her team had to get creative with something called adaptive optics. This method works by deforming the telescope’s mirror in real time in order to overcome fluctuations in the atmosphere.
Thanks to adaptive optics, Andrea and her team were able to capture images that were 10-30 times clearer than what was previously possible. By studying the orbits of stars that hang out near the center, she was able to determine that a supermassive black hole with four millions times the mass of the sun must lie there. Thanks to this telescope hack, Andrea and other scientists will be able to study the effects of black holes on gravity and galaxies right here at home. You can watch her explain her work briefly in the video after the break. Congratulations, Dr. Ghez, and here’s to another 25 years of fruitful research.
It’s a build executed in the modern style, taking full advantage of contemporary design tools and processes. The entire robot is built around twelve servo motors that provide rotation and translation to the robot’s joints. After importing the servo models into Fusion 360, [Technovation] set about building the rest of the body around them. An Arduino Uno runs the show, which addresses the many servos thanks to a Sensor Shield that has a multitude of useful outputs.
[Technovation] put a specific focus on durability and robustness during the design phase. The platform is intended as a test bed for various walking styles and gaits, and thus any hardware failures would be an unnecessary distraction from the project’s goals. The chassis is a great platform to learn on, and we expect to see further developments in future.