Clockwork Rover For Venus

Venus hasn’t received nearly the same attention from space programs as Mars, largely due to its exceedingly hostile environment. Most electronics wouldn’t survive the 462 °C heat, never mind the intense atmospheric pressure and sulfuric acid clouds. With this in mind, NASA has been experimenting with the concept of a completely mechanical rover. The [Beardy Penguin] and a team of fellow students from the University of Southampton decided to try their hand at the concept—video after the break.

The project was divided into four subsystems: obstacle detection, mechanical computer, locomotion (tracks), and the drivetrain. The obstacle detection system consists of three (left, center, right) triple-rollers in front of the rover, which trigger inputs on the mechanical computer when it encounters an obstacle over a certain size. The inputs indicate the position of each roller (up/down) and the combination of inputs determines the appropriate maneuver to clear the obstacle. [Beardy Penguin] used Simulink to design the logic circuit, consisting of AND, OR, and NOT gates. The resulting 5-layer mechanical computer quickly ran into the limits of tolerances and friction, and the team eventually had trouble getting their design to work with the available input forces.

Due to the high-pressure atmosphere, an on-board wind turbine has long been proposed as a viable power source for a Venus rover. It wasn’t part of this project, so it was replaced with a comparable 40 W electric motor. The output from a logic circuit goes through a timing mechanism and into a planetary gearbox system. It changes output rotation direction by driving the planet gear carrier with the sun gear or locking it in a stationary position.

As with many undergraduate engineering projects, the physical results were mixed, but the educational value was immense. They got individual subsystems working, but not the fully integrated prototype. Even so, they received several awards for their project and even came third in an international Simulink challenge. It also allowed another team to continue their work and refine the subsystems. Continue reading “Clockwork Rover For Venus”

Geochron world time clock

Geochron: Another Time, Another Timeless Tale

The Geochron World Time Indicator is a clock that doubles as a live map of where the sun is shining on the Earth. Back in its day, it was a cult piece that some have dubbed the “Rolex on the wall.” Wired’s recent coverage of the clock reminded us of just how cool it is on the inside. And to dig in, we like [Attoparsec]’s restoration project on his own mid-1980s Geochron, lovingly fixing up a clock he picked up online.

[Attoparsec]’s recent restoration shares insights into the clock’s fascinating mechanics. Using a synchronous motor, transparent slides, and a lighted platen, the Geochron works like a glorified slide projector, displaying the analemma—a figure-eight pattern that tracks the sun’s position over the year.

But if you’re looking for a digital version, way back in 2011 we showcased [Justin]’s LED hack of FlorinC’s “Wise Clock”, which ingeniously emulated the Geochron’s day-night pattern using RGB LEDs, swapping out the faceplate for a world map printed on vellum. That’s probably a much more reasonable way to go these days. Why haven’t we seen more remakes of these?

The Glacial IPv6 Transition: Raising Questions On Necessity And NAT-Based Solutions

A joke in networking circles is that the switch from IPv4 to IPv6 is always a few years away. Although IPv6 was introduced in the early 90s as a result of the feared imminent IPv4 address drought courtesy of the blossoming Internet. Many decades later, [Geoff Huston] in an article on the APNIC blog looks back on these years to try to understand why IPv4 is still a crucial foundation of the modern Internet while IPv6 has barely escaped the need to (futilely) try to tunnel via an IPv4-centric Internet. According to a straight extrapolation by [Geoff], it would take approximately two more decades for IPv6 to truly take over from its predecessor.

Although these days a significant part of the Internet is reachable via IPv6 and IPv6 support comes standard in any modern mainstream operating system, for some reason the ‘IPv4 address pool exhaustion’ apocalypse hasn’t happened (yet). Perhaps ironically, this might as [Geoff] postulates be a consequence of a lack of planning and pushing of IPv6 in the 1990s, with the rise of mobile devices and their use of non-packet-based 3G throwing a massive spanner in the works. These days we are using a contrived combination of TLS Server Name Indication (SNI), DNS and Network Address Translation (NAT) to provide layers upon layers of routing on top of IPv4 within a content-centric Internet (as with e.g. content distribution networks, or CDNs).

While the average person’s Internet connection is likely to have both an IPv4 and IPv6 address assigned to it, there’s a good chance that only the latter is a true Internet IP, while the former is just the address behind the ISP’s CG-NAT (carrier-grade NAT), breaking a significant part of (peer to peer) software and services that relied on being able to traverse an IPv4 Internet via perhaps a firewall forwarding rule. This has now in a way left both the IPv4 and IPv6 sides of the Internet broken in their own special way compared to how they were envisioned to function.

Much of this seems to be due to the changes since the 1990s in how the Internet got used, with IP-based addressing of less importance, while giants like Cloudflare, AWS, etc. have now largely become ‘the Internet’. If this is the path that we’ll stay on, then IPv6 truly may never take over from IPv4, as we will transition to something entirely else. Whether this will be something akin to the pre-WWW ‘internet’ of CompuServe and kin, or something else will be an exciting revelation over the coming years and decades.

Header: Robert.Harker [CC BY-SA 3.0].

Sad clown holding melted ice cream cone

McDonalds Ice Cream Machines Gain A DMCA Exemption

An unlikely theatre for an act in the right-to-repair saga came last year in the form of McDonalds restaurants, whose McFlurry ice cream machines are prone to breakdown. The manufacturer had locked them down, and a franchisee with a broken machine had no option but to call them for an expensive repair job. iFixit and Public Knowledge challenged this with a request for a DMCA exemption from the Copyright Office, and now news emerges that this has been granted.

The exemption in question isn’t specific to McDonalds, instead it applies to retail food preparation equipment in general, which includes ice-cream machines. We’re guessing that franchisees won’t be breaking out the screwdrivers either, instead it’s likely to lower significantly the cost of a service contract for them and any other food industry operators hit with the same problem. Meanwhile any hackers who’ve picked up an old machine can now fix it themselves without breaking the law, and maybe the chances of your local Mickey D’s having no McFlurries have gone down.

This story has featured more than once on these pages, so catch up here, and here.

A New Chinese Radio Breaks Cover, Is It Worth It?

Scanning the firehose of new electronic kits and modules coming from the usual Chinese suppliers can be a rewarding experience, as sometimes among the endless breakout boards comes an item that looks interesting enough to try. As an example there’s a receiver kit being given a quick review by [Tech Minds], offering AM and HF multi-mode, FM broadcast, and air band alongside what appear to be digital streaming features.

Looking at it, though all the RF part is hidden under screening cans we’re guessing it might contain one of the Silicon Labs all-in-one receiver chips, but the whole appears to deliver a useful receiver with a comprehensive interface. The review isn’t quite technical enough so we can’t glean a lot more, but it looks as though it could be useful. We’d be tempted to snag one for review, but since with very few exceptions we pay for the stuff we review, it’s a mite expensive at $50+ for yet another radio.

There’s an ongoing question with all these cheap kits and modules though, first of all where did the design come from and are we freeloading on someone else’s hard work, but then whether or not what you’re getting is a knock-off using defective semiconductors or with bean-counting parts removal degrading performance. We’re guessing more will come out about this radio in due course, and we can all make our own judgement. Meanwhile this one can be found on AliExpress or Banggood, so take a look and see if you’re tempted.

Continue reading “A New Chinese Radio Breaks Cover, Is It Worth It?”

DIY Laser Tag Project Does It In Style

This DIY lasertag project designed by [Nii], which he brought to Tokyo Maker Faire back in September, is a treasure trove. It’s all in Japanese and you’ll need to visit X (formerly Twitter) to see it, but the images do a fine job of getting the essentials across and your favorite translator tool will do a fair job of the rest.

There’s a whole lot to admire in this project. The swing-out transparent OLED display is super slick, the electronics are housed on a single PCB, the back half of the grip is in fact a portable USB power bank that slots directly in to provide power, and there’s a really smart use of a short RGB LED strip for effects.

The optical elements show some inspired design, as well. An infrared LED points forward, and with the help of a lens, focuses the beam tightly enough to make aiming meaningful. For detecting hits, the top of the pistol conceals a custom-made reflector that directs any IR downward into a receiver, making it omnidirectional in terms of hit sensing but only needing a single sensor.

Want to know more? Check out [Nii]’s earlier prototypes on his website. It’s clear this has been in the works for a while, so if you like seeing how a project develops, you’re in for a treat.

As for the choice of transparent OLED displays? They are certainly cool, and we remember how wild it looks to have several stacked together.

RF Detector Chip Helps Find Hidden Cameras And Bugs

It’s a staple of spy thriller movies, that the protagonist has some kind of electronic scanner with which he theatrically searches his hotel room to reveal the bad guys’ attempt to bug him. The bug of course always had a flashing LED to make it really obvious to viewers, and the scanner was made by the props department to look all cool and futuristic.

It’s not so far-fetched though, while bugs and hidden cameras in for example an Airbnb may not have flashing LEDs, they still emit RF and can be detected with a signal strength meter. That’s the premise behind [RamboRogers]’ RF hunter, the spy movie electronic scanner made real.

At the rear of the device is an ESP32, but the front end is an AD8317 RF detector chip. This is an interesting and useful component, in that it contains a logarithmic amplifier such that it produces a voltage proportional to the RF input in decibels. You’ll find it at the heart of an RF power meter, but it’s also perfect for a precision field strength meter like this one. That movie spy would have a much higher chance of finding the bug with one of these.

For the real spies of course, the instruments are much more sophisticated.