Farting Baseball; From the Makers of Self-Solving Rubik’s Cube

Some hackers have a style all their own that is immediately recognizable from one project to the next. For instance, you can tell a [Takashi Kaburagi] by its insides. The behavior of his Farting Baseball project (machine translation) is amusing, but the joke is only skin deep. Look inside and you’ll gain a huge appreciation for what has been done here. It’s not as mind-boggling as his work on the self-solving Rubiks cube robot, but the creativity and design constraints are similarly impressive.

Clever detail is the square of soft material used to cushion impact

This whimsical project is a curve ball no matter who throws it. While in flight, a jet of compressed gas can alter the trajectory at the press of a button. Inside is a small pressure vessel that is filled with HFC134A refrigerant commonly used on gas blowback pistols. It’s a non-combustible that lies in wait until a solenoid is activated to release the pressure in a powerful jet. The ball carries a CR2032 to power the wireless link for activation, but that solenoid needs more juice so capacitors are charged for this purpose.

It’s worth digging through the details on this one, including the article on measuring discharge time (machine translation). There are numerous nice touches, like the yellow Whoopee Cushion neck that directs the jet, the capacitor discharge materials so there is not an accidental activation when not in use, and clever and clean construction that make everything fit.

Another hacker with an equally iconic style is [Mohit Bhoite]’s work; make his flywire sculptures your next stop.

Posted in 134a, baseball, classic hacks, curveball, gas blowback pistols, HFC134A, solenoid, wireless | Leave a comment

Hybrid Drones Could Have Massively Extended Flight Times

Multirotor drones truly took off with the availability of lithium polymer batteries, brushless motors, and cheap IMUs. Their performance continues to improve, but their flight time remains relatively short due to the limits of battery technology. [Nicolai Valenti] aims to solve the problem by developing a hybrid generator for drones.

The basic concept consists of a small gasoline engine, connected to a brushless motor employed as a generator. The electricity generated is used to run the main flight motors of the multirotor drone. The high energy density of gasoline helps to offset the added weight of the generator set, and [Nicolai] is aiming to reach a goal of two hours of flight time.

There are many engineering problems to overcome. Engine starting, vibration and rectification are all significant challenges, but [Nicolai] is tackling them and has already commenced flight testing. Experiments are ongoing with 500 W, 1,000 W, and 2,000 W designs, and work is ongoing to optimise the engine and electronics package.

It’s a project that holds the potential to massively expand the range of operation for medium to large multirotors, and should unlock certain capabilities that have thus far been limited by short battery runtimes. Gasoline powered drones aren’t a new idea, but we’ve seen precious little in the hybrid space. We look forward to seeiing how this technology develops. Video after the break.

Posted in drone, drone hacks, gasoline, hybrid, hybrid drone | Leave a comment

Turning A Single Bolt Into A Combination Lock

In our search for big-box convenience, we tend to forget that locksmiths once not only copied keys but also created complex locks and other intricate mechanisms from scratch. [my mechanics] hasn’t forgotten, and building a lock is his way of celebrating of the locksmith’s skill. Building a combination lock from a single stainless bolt is probably also showing off just a little, and we’re completely fine with that.

Granted, the bolt is a rather large one – an M20x70 – and a few other materials such as brass rod and spring wire were needed to complete the lock. But being able to look at a single bolt and slice it up into most of the stock needed for the lock is simply amazing. The head became the two endplates, while the shank was split in half lengthwise and crosswise after the threads were turned off; those pieces were later turned down into the tubes and pins needed to create the lock mechanism. The combination wheels probably could have come from another – or longer – bolt, but we like the look of the brass against the polished stainless, as well as the etched numbers and subtle knurling. The whole thing is a locksmithing tour de force, and the video below captures all of it without any fluff or nonsense.

If working in steel and brass isn’t your thing, fear not – a 3D-printed combination lock is probably within your reach. Or laser cut wood. Or even plain paper, if you’re not into the whole security thing.

Posted in brass, combination lock, lock, lockpicking hacks, locksmithing, misc hacks, steel | Leave a comment

A (Card) Table-Top Turing Machine Of Magic: The Gathering Cards

Within normal rules of collectible card game Magic: The Gathering a player may find themselves constrained to only a single legal course of action forward. It’s a situation players could craft to frustrate their opponents, though the victims usually break free after a few moves. But under a carefully crafted scenario, players would have no choice but to become the execution engine for a Turing-complete programming language written with Magic cards via techniques detailed in this paper.

One of the authors of this paper, [Alex Churchill], started working on this challenge in 2010. We covered an earlier iteration of his work here, and his own criticism that it was dependent on player cooperation. At various points, the game rules state a player “may” take certain actions and the construct falls apart if our player chooses the wrong thing. It would be as if a computer was built out of transistors that “may” switch as commanded or not, which would not be a very reliable method of computation.

To improve reliability of this particular Turing machine execution engine, the team combed through rules and cards to devise an encoding where the player is only ever presented with a single legal course forward. This ensures deterministic execution of the instruction stream, and now with proof of Turing-completeness in hand, we congratulate [Alex] on a successful conclusion to his decade-long quest.

We have a primer available for anyone who wants a refresher on Turing machines. They are utterly impractical but fun for hackers to build, and they are typically constructed of electronics and LEDs instead of ink on cardboard.

Via Ars Technica, who have presented their own analysis of this machine.

Main image: Unspecified set of Magic: The Gathering cards by [Robert] CC BY 2.0

Posted in card game, magic the gathering, toy hacks, Turing machine | Leave a comment

Live Apollo 11 Transcript On eInk Display

There are few moments in history that have ever been recorded in more detail or analyzed as thoroughly as the Apollo 11 mission to the Moon. Getting three men to our nearest celestial neighbor and back in one piece took a lot of careful planning, and recording every moment of their journey was critical to making sure things were going smoothly. As we celebrate the 50th anniversary of man’s first steps off our world, these records give us a way to virtually tag along with Armstrong, Aldrin, and Collins.

As part of the 50th anniversary festivities at the Parkes Radio Telescope in Australia, [Andrew] created a badge that would let him wear a little piece of Apollo 11. Using an ESP32 and an eInk screen, it replays the mission transcript between the crew and ground control in real-time. It’s a unique way to experience the mission made possible by that meticulous data collection that’s a hallmark of the National Aeronautics and Space Administration.

[Andrew] was inspired by the “Apollo 11 In Real Time” website, but rather than pulling the content from the Internet, he’s loaded the mission transcripts onto the ESP32’s SPIFFS filesystem as a CSV file. Not that the badge is completely offline, it does need to connect to the Internet (via a hotspot on his phone) so it can keep its internal clock synchronized with NTP. Keeping everything local does reduce power consumption compared to streaming it from the Internet, but he admits that otherwise he didn’t give much thought to energy efficiency and there’s definitely some room for improvement.

The LILYGO TTGO board he’s using combines the ESP32 with a 2.13 inch eInk display, in a formfactor not unlike the Badgy we’ve covered previously. He was able to find a STL for a 3D printed case on Thingiverse which he modified to fit a battery. Unfortunately the original model was released under a license that prevents him from distributing his modified version, but it doesn’t sound too difficult to replicate if you’re interested in building your own running ticker of humanity’s greatest adventure.

Posted in apollo, badge, csv, eink, Microcontrollers, moon, wearable hacks | Leave a comment

Torturing an Instrumented Dive Watch, for Science

The Internet is a wild and wooly place where people can spout off about anything with impunity. If you sound like you know what you’re talking about and throw around a few bits of the appropriate jargon, chances are good that somebody out there will believe whatever you’re selling.

Case in point: those that purport that watches rated for 300-meter dives will leak if you wiggle them around too much in the shower. Seems preposterous, but rather than just dismiss the claim, [Kristopher Marciniak] chose to disprove it with a tiny wireless pressure sensor stuffed into a dive watch case. The idea occurred to him when his gaze fell across an ESP-01 module next to a watch on his bench. Figuring the two needed to get together, he ordered a BMP280 pressure sensor board, tiny enough itself to fit anywhere. Teamed up with a small LiPo pack, everything was stuffed into an Invicta dive watch case. A little code was added to log the temperature and pressure and transmit the results over WiFi, and [Kristopher] was off to torture test his setup.

The first interesting result is how exquisitely sensitive the sensor is, and how much a small change in temperature can affect the pressure inside the case. The watch took a simulated dive to 70 meters in a pressure vessel, which only increased the internal pressure marginally, and took a skin-flaying shower with a 2300-PSI (16 MPa) pressure washer, also with minimal impact. The video below shows the results, but the take-home message is that a dive watch that leaks in the shower isn’t much of a dive watch.

Hats off to [Kristopher] for doing the work here. We always love citizen science efforts such as this, whether it’s hardware-free radio astronomy or sampling whale snot with a drone.

Posted in BMP280, clock hacks, crown, depth, dving, ESP-01, misc hacks, pressure, seal, sensor, temperature, watch, water pressure, wifi | Leave a comment

The Arduboy, Ported To Desktop and Back Again

A neat little hacker project that’s flying off the workbenches recently is the Arduboy. This tiny game console looks like a miniaturized version of the O.G. Game Boy, but it is explicitly designed to be hacked. It’s basically an Arduino board with a display and a few buttons, anyway.

[rv6502] got their hands on an Arduboy and realized that while there were some 3D games, there was nothing that had filled polygons, or really anything resembling a modern 3D engine. This had to be rectified, and the result is pretty close to Star Fox on a microcontroller.

This project began with a simple test on the Arduboy to see if it would be even possible to render 3D objects at any reasonable speed. This test was just a rotating cube, and everything looked good. Then began a long process of figuring out how fast the engine could go, what kind of display would suit the OLED best, and how to interact in a 3D world with limited controls.

Considering this is a fairly significant engineering project, the fastest way to produce code isn’t to debug code on a microcontroller. This project demanded a native PC port, so all the testing could happen on the PC without having to program the Flash every time. That allowed [rv] to throw out the Arduino IDE and USB library; if you’re writing everything on a PC and only uploading a hex file to a microcontroller at the end, you simply don’t need it.

One of the significant advances of the graphics capability of the Arduboy comes from exploring the addressing modes of the OLED. By default, the display is in a ‘horizontal mode’ which works for 2D blitting, but not for rasterizing polygons. The ‘vertical addressing mode’, on the other hand, allows for a block of memory, 8 x 128 bytes, that maps directly to the display. Shove those bytes over, and there’s no math necessary to display an image.

This is, simply, one of the best software development builds we’ve seen. It’s full of clever tricks (like simply not doing math if you’ll never need the result) and stuffing animations into far fewer bytes than you would expect. You can check out the demo video below.

Posted in 3D render, Arduboy, arduino, Arduino Hacks, game engine, software, Software Development | Leave a comment

BornHack Tease Us With Their Badge

Every August for the past four years, there has been a summer hacker camp on the Danish island of Bornholm, that may be a relatively new kid on the block but is slowly evolving into one of the summer’s essential stop-offs. This year for the first time they are moving to a larger site in an easier-to-reach part of the country, and in the usual build-up to the event they have released a teaser image of their badge.

Of course, you will want to know a little more about it than the picture can convey, so the BornHack folks were kind enough to give us a few more details. At its heart is a Silicon Labs Happy Gecko EFM32HG322F64G microcontroller, the same 25 MHz ultra-low-power ARM Cortex M0+ part that has featured in the previous BornHack offerings. Power comes from a pair of AA cells, and it sports a 240 x 240 pixel colour IPS display and an SD card holder. Connectivity is via USB and an infra-red interface for badge-to-badge communication, and human interface is via a mini joystick switch. Finally, it has a six-way v1.69bis Shitty Addon connector.

By some standards this is a relatively modest offering, but by using an evolution of their hardware from previous years as well as the same proven Geckoboot bootloader they are far more likely to deliver a satisfactory user experience than had they opted for a more ambitious design. We’ll be attending the camp, so we’ll report on the finished article once we have it.

BornHack will run from the 8th to the 15th of August, on the Danish island of Funen. There are a range of tickets still available, from single day visits to the whole week for 1200 DKK (about €160, or $181). Compared to some other events on our community’s calendar, we think that represents a bargain.

Posted in badge, BornHack, cons, hacker camp | Leave a comment

Art Meets Science In The Cold Wastelands Of Iceland

Although Iceland is now a popular destination for the day-tripping selfie-seeking Instagrammer who rents a 4×4, drives it off road onto delicate ecosystems and then videos the ensuing rescue when the cops arrive, there are still some genuine photographers prepared to put a huge amount of time and effort into their art. [Dheera Venkatraman] is one of the latter and produces composite photos using a relatively low resolution thermal camera and DIY pan and tilt rig.

Whilst we don’t have the exact details, we think that, since the Seek Reveal Pro camera used has a resolution of 320 x 240, [Dheera] would have had to take at least 20 photos for each panoramic shot. In post processing, the shots were meticulously recombined into stunning landscape photos which are a real inspiration to anybody interested in photography.

If you do go to Iceland you might find the traditional food a little challenging to those not raised upon it, nor would you go there for a stag night as beer is eyewateringly expensive. But if you enjoy uninhabitable, desolate, dramatic landscapes there is a huge range of possibilities for the photographer from rugged, frozen lava flows to extra terrestrial ‘Martian’ crater-scapes, if you know where to find them.

[Dheera’s] blog contains some more information about his Iceland photography and there’s a Github repsoitory too. And if you cant afford a $699 Seek Reveal Pro, maybe try building one yourself.

Posted in art, digital cameras hacks, Iceland, landscape, photography, Thermal | Leave a comment

High-Tech Alms Collection With The ESP32

In an ideal world, shop space, tools, and components would be free. But until we get to that Star Trek utopia, hackerspaces will have to rely on donations from the community to help stay afloat. While asking for money, at least you can have some fun with it if you design and build an Internet-connected donation box.

Or at least that’s how [Goran Mahovlic] handled it for the Radiona hackerspace in Zagreb, Croatia. Not content with just cutting a slit in the top of a shoe box, he came up with a physical donation system that’s not only more informative for those donating, but more organized for those collecting the funds.

The key is a arcade-style programmable coin acceptor from SparkFun. When connected to a microcontroller, this allows the box to keep a running tally on how much money has been inserted. With the use of a RFM96 LoRa module, it can even report on the current haul while remaining mobile; perfect for when the hackerspace has events outside of their home base.

But counting quarters is hardly a task befitting a powerful microcontroller like the ESP32. So [Goran] gave the chip something to do in its spare time by adding a couple of buttons and an LCD. This allows the user to scroll through a list of various projects that are looking for donations, and decide which one they want to financially support. When the donation box counts how much money has been inserted, it records which project its been earmarked for.

Of course, if you’d rather the free market do its thing, we’ve seen this same coin acceptor used to build a locker-sized vending machine. Or if you’re feeling crafty, you could always try your hand at building one with cardboard.

Posted in coin acceptor, donations, ESP32, hackerspace, LoRa, Microcontrollers, parts | Leave a comment