Rocket League is a video game famous for being wildly popular despite being virtually unplayable without several hours practice. It involves hyper fast cars playing soccer, complete with the ability to flip, jump, and rocket boost into the ball. [mrak_ripple] decided he wanted some of that action in a real RC car, and set to work.
While rocket boosts were out of scope for this build, [mrak_ripple] was pretty confident he could build a jumping, flipping RC car modelled after the Rocket League Octane vehicle. Initial experiments involved a custom 3D printed spring mechanism, but the results were underwhelming. Instead, in the true hacker spirit, a jumping mechanism was taken from an existing toy, and installed in the car instead. This was combined with a mechanism built out of a brushless motor with a flywheel added to generate a flipping moment in mid-air.
The final result is impressive, with the car flipping relatively cleanly once refined and lightened from its original design. We’d love to see a two-axis build that can front- and back-flip as well. It’s a step up in complexity from the last build we saw from [mrak_ripple], the amusing mashed potato trebuchet. Video after the break.
Rocket League is a video game famous for being wildly popular despite being virtually unplayable without several hours practice. It involves hyper fast cars playing soccer, complete with the ability to flip, jump, and rocket boost into the ball. [mrak_ripple] decided he wanted some of that action in a real RC car, and set to work.
While rocket boosts were out of scope for this build, [mrak_ripple] was pretty confident he could build a jumping, flipping RC car modelled after the Rocket League Octane vehicle. Initial experiments involved a custom 3D printed spring mechanism, but the results were underwhelming. Instead, in the true hacker spirit, a jumping mechanism was taken from an existing toy, and installed in the car instead. This was combined with a mechanism built out of a brushless motor with a flywheel added to generate a flipping moment in mid-air.
The final result is impressive, with the car flipping relatively cleanly once refined and lightened from its original design. We’d love to see a two-axis build that can front- and back-flip as well. It’s a step up in complexity from the last build we saw from [mrak_ripple], the amusing mashed potato trebuchet. Video after the break.
Rocket League is a video game famous for being wildly popular despite being virtually unplayable without several hours practice. It involves hyper fast cars playing soccer, complete with the ability to flip, jump, and rocket boost into the ball. [mrak_ripple] decided he wanted some of that action in a real RC car, and set to work.
While rocket boosts were out of scope for this build, [mrak_ripple] was pretty confident he could build a jumping, flipping RC car modelled after the Rocket League Octane vehicle. Initial experiments involved a custom 3D printed spring mechanism, but the results were underwhelming. Instead, in the true hacker spirit, a jumping mechanism was taken from an existing toy, and installed in the car instead. This was combined with a mechanism built out of a brushless motor with a flywheel added to generate a flipping moment in mid-air.
The final result is impressive, with the car flipping relatively cleanly once refined and lightened from its original design. We’d love to see a two-axis build that can front- and back-flip as well. It’s a step up in complexity from the last build we saw from [mrak_ripple], the amusing mashed potato trebuchet. Video after the break.
By now, the wearing of a facemask to protect ourselves from pandemic infection is for many of us a daily fact of life. Perhaps that means a cheap disposable mask, but there’s no reason that has to be the case. It’s easy to make more durable masks that can be washed and re-used time and time again, and our Hackaday colleague [Kristina Panos] has shared her pattern and workflow to help you do it.
Her pattern isn’t a complex cut-out but a simple rectangle, and the trick of sewing them together and flipping them inside out makes for a very tidy result. With three pleats pressed in and the elastic sewn up the result is a mask that’s neat, attractive, effective, and cheap, which is a win in our book.
It’s worth repeating her important point that these are not for use in medical environments, instead they’re the standard street-wear aerosol catchers we’re all used to.This isn’t the first time we’ve looked at masks here at Hackaday, or indeed though [Kristana]’s are by far the tidier neither is it first time one of us has made a mask. We looked at them in depth last year in our surviving the pandemic as a hacker series.
Old Civil Defense survey meters like the V-715 are interesting conversation starters, but of very little practical use today. These devices were intended to be a sort of litmus test that survivors of a nuclear blast could use to determine when it was safe to venture out of their radiation shelter: if the needle on the meter moves, even when it’s on the most sensitive setting, you should probably go back inside. Since [Hamilton Karl] would (hopefully) never need such an indicator, he decided to have a little fun with this Cold War holdover and turn it into a Disco Containment Unit.
Technical details are a little sparse on this one, but we can infer most of it just from the pictures. In place of the original meter [Hamilton] has mounted a tiny mirrored ball inside of a protective cage, which is spun by a geared motor that’s occupying the space that used to be taken up by the ion chamber.
A handful of Adafruit NeoPixel RGB LEDs, an Arduino Nano, and a few switches to control it all round out the functional aspects of the build, and a new disco-themed trefoil replaces the original Civil Defense logo on the side. The project page mentions there’s a piezo buzzer onboard that performs a stirring rendition of “Stayin’ Alive” by the Bee Gees, but alas there’s no video that shows it in action.
Thanks to the rugged construction and built-in handle of these old survey meters, [Hamilton] can now take the party with him wherever he goes. Not that he can really go anywhere with this whole global pandemic hanging over our heads, but at least he’ll be ready when things start trending towards normal. In a way the device’s functionality has now been reversed from how it originally worked, since the meter going wild will now be an indicator that its safe to come out.
You may have been one of the many of us who received an email from Ubiquiti this week, recommending a password change. The email stated that there was an unauthorized access of Ubiquiti systems, and while there wasn’t evidence of user data being accessed, there was also not enough evidence to say emphatically that user data was not accessed. Ubiquiti has mentioned that the database that may have been accessed contains a user’s name, email address, hashed password, and optionally the mailing address and phone number.
Depending on how the Ubiquiti authentication system is designed, that hashed password may be enough to log in to someone’s account. In any case, updating your password would invalidate the potentially compromised hash. This event underscores a complaint voiced by Ubiquiti users: Ubiquiti has been making it harder to avoid administrating hardware with local only accounts.
The repository contained code from Nissan mobile apps, marketing information, and code for internal-only services. The 18.4 GB data dump is still available on the darker corners of the internet, via torrent files.
It’s worth taking a minute to call out the ISC and similar efforts for their invaluable work. The ISC primarily serves as a clearinghouse for data from Intrusion Detection Systems and firewalls around the internet. When new patterns emerge, volunteers watching the data can quickly identify new attacks as they emerge. In some cases, this quick response can give administrators around the world time to patch the vulnerability being targeted before they are compromised.
Dovecot Hibernation
Dovecot has released version 2.3.13, and there is a fix for a notable vulnerability, CVE-2020-24386. IMAP supports an IDLE command, putting the connection to the server in a holding pattern, ready to push real-time mail notifications to the client. The vulnerability allows a client to put its connection in this state, and then send a malicious request to the server. This request can allow for limited filesystem access, most notably the downloading of messages from other accounts. It’s possible to mitigate the flaw through disabling IMAP hibernation, but the recommendation is to simply update to the latest release.
Telegram Triangulation
Telegram is one of the go-to solutions for sending secure messages. Just over a year ago, Telegram introduced “People Near Me”, a feature for finding nearby users who have opted in to the service. If you’ve opted in, you might consider going and turning that feature off. Telegram gives a very precise and accurate distance to anyone else who is within seven miles. That distance updates in real time, which is great for meetups. What might not be immediately obvious is that it’s rather trivial to spoof a device’s location to anywhere in the world. Within a few minutes, it’s possible to precisely locate anyone in the world who has Telegram’s location service turned on. Other services have prevented this problem by giving less precise location data. So far, Telegram has responded that this is not a bug, and it doesn’t plan to make any changes.
How Solarwinds Got Hacked
More details on the Solarwinds backdoor is slowly coming to light. The more information is revealed, the more interesting the story becomes. This week, we got Crowdstrike’s write-up of the malware running on Solarwinds machines. This malware, dubbed Sunspot, isn’t the Orion backdoor itself, it is a custom-written piece of malware that modifies source code surreptitiously at compile time. This brings to mind the old Trusting Trust attack.
Sunspot was written to very carefully hide from detection, and to only take action when it detects code compiling. It checks once a second for MsBuild.exe, and whether it was building Orion. If it is, it modifies one source code file, waits for compilation to complete, and then undoes the malicious change. A developer would be hard pressed to discover the modification, because it only exists during compilation, while the developer is out getting coffee anyway. We were somewhat skeptical when Solarwinds first called this a “sophisticated and novel” hack, but the evidence seems to affirm that opinion.
A recent research paper shows a way to create multicolor 3D prints using a single extruder if you are too lazy to babysit the machine and switch filament. The concept: print your own “programmable” filament that has the right colors in the right place. This is the same idea as manually splicing filament but presumably is more efficient since the process works with one color at a time and doesn’t repeat. In other words, to print the 64 squares of a chessboard you’d swap filament at least 64 times on each layer. Using programmable filament, you’d load one spool, print half of the filament, load another spool, print the other half, and then finally load the newly created filament and print the chessboard. Notice that the first two operations aren’t printing the chessboard. They are printing the spool of filament you feed through on the third pass.
There are machines made to do this, of course, although they generally just splice lengths of filament together for you automatically. Using one filament solves the problems of keeping multiple heads in alignment as well as the added cost and complexity. However, you now have different problems such as the transition between materials and knowing exactly how much material will be at each point in the print.
We wondered how much filament you can print spooled up on a reasonable size print bed. According to the paper:
The maximum length of a printed filament is highly dependent on the build area given the type of 3D printer. With a 300×300 mm bed size, a printed filament in a spiral shape can be approximately 20-m long.
Printing the working filament is time-consuming, too. The paper reports that a boat that took two hours to print required five hours to print the programmable filament. Still better than swapping a bunch of plastic by hand, we suppose.
Oddly enough, the inspiration for this paper came from an Instructable. If you plan to try this, you might want to watch the videos there about printing hexagonal filaments with different colors.
With the aim of reducing virus transmission due to gatherings during the pandemic, the Dutch government have banned fireworks. The people of the Netherlands like their noisy things so we’re told that the ban has been widely flouted, but [Build Comics] are a law-abiding group of workshop tool heroes. For their lockdown noise, they created an entirely-legal pulsejet. The interesting part is that it was made entirely using fairly basic tools on a minimalist budget, with TIG and MIG eschewed in favour of a mundane stick welder.
The form of the pulse jet will probably be familiar as it has been taken from other published designs. A long tube is bent back upon itself with a combustion chamber placed in one of its arms such that the jet forms a resonant chamber that produces continuous pulses of exhaust gas. This one is made from stainless steel tube, and the exhaustive documentation should be worth a look for anyone tempted to make their own. Welding thin sheet with a stick welder requires quite a bit of skill, and in a few places they manage to burn a hole or two. One requires a patch, but the time-honoured technique of running a bead around the edge manages to successfully close another.
Their first attempt to fire it up using a leaf blower with a 3D-printed adapter fails, but following the construction of a more resilient part and a more efficient gas injector the engine starts. It’s then taken out on a farm for some serious noise without too many angry neighbours, as you can see in the video below the break.
The hero tools of Build Comics have appeared here before, most recently with an analogue meter clock.
While most PCBs stick to tried-and-true methods of passing electrons through their layers of carefully-etched copper, modern construction methods allow for a large degree of customization of most aspects of these boards. From solder mask to number of layers, and even the shape of the board itself, everything is open for artistic license and experimentation now. [Luca] shows off some of these features with his PCB which acts as a live map of Italy.
The PCB is cut out in the shape of the famous boot, with an LED strategically placed in each of 20 regions in the country. This turns the PCB into a map with the RGB LEDs having the ability to be programmed to show any data that one might want. It’s powered by a Wemos D1 Mini (based on an ESP8266) which makes programming it straightforward. [Luca] has some sample programs which fetch live data from various sources, with it currently gathering daily COVID infection rates reported for each of the 20 regions.
The ability to turn a seemingly boring way to easily attach electronic parts together into a work of art without needing too much specialized equipment is a fantastic development in PCBs. We’ve seen them turned into full-color art installations with all the mask colors available, too, so the possibilities for interesting-looking (as well as interesting-behaving) circuits are really opening up.
Between hot things, sharp things, and spinny things, there’s more than enough danger in the average hacker’s shop to maim and mutilate anyone who fails to respect their power. But somehow lasers don’t seem to earn the same healthy fear, which is strange considering permanent blindness can await those who make a mistake lasting mere fractions of a second.
To avoid that painful fate, high-power laser fan [Brainiac75] undertook building a beam dump, which is a safe place to aim a laser beam in an experimental setup. His version has but a few simple parts: a section of extruded aluminum tubing, a couple of plastic end caps, and a conical metal plumb bob. The plumb bob gets mounted to one of the end caps so that its tip points directly at a hole drilled in the center of the other end cap. The inside and the outside of the tube and the plumb bob are painted with high-temperature matte black paint before everything is buttoned up.
In use, laser light entering the hole in the beam dump is reflected off the surface of the plumb bob and absorbed by the aluminum walls. [Brainiac75] tested this with lasers of various powers and wavelengths, and the beam dump did a great job of safely catching the beam. His experiments are now much cleaner with all that scattered laser light contained, and the work area is much safer. Goggles still required, of course.
Hats off to [Brainiac75] for an instructive video and a build that’s cheap and easy enough that nobody using lasers has any excuse for not having a beam dump. Such a thing would be a great addition to the safety tips in [Joshua Vasquez]’s guide to designing a safe laser cutter.
Soil moisture sensors are cheap and easy to interface with, to the point that combining one with an Arduino and blinking an LED when your potted plant is feeling a bit parched is a common beginners project. But what about on the long term? Outside of a simple proof of concept, what would it take to actually read the data from these sensors over the course of weeks or months?
That’s precisely the question [derflob] recently had to answer. The goal was to build a device that could poll multiple soil sensors and push the data wirelessly into Home Assistant. But since it would be outside on the balcony, it needed to run exclusively on battery power. Luckily his chosen platform, the ESP32, has some phenomenal power saving features. You just need to know how to use them.
The custom board can read from six soil sensors.
In his extremely detailed blog post, [derflob] goes over some of the tricks he used to eek out as much runtime as possible. The big one, and arguably the key to the whole project, is his use of the ESP32’s Ultra-Low Power coprocessor (ULP). This powerful feature allows the microcontroller to do some useful work, albeit with a reduced instruction set, without waking up the power-hungry primary processor.
Since the ULP can read from the ADC, he was able to craft some assembly code that only wakes the CPU if the readings from one of the six connected sensors has changed more than a set threshold value since the last update. This keeps the chip asleep the majority of the time, and so far, [derflob] says his board has been humming along for six months on a single LiFePO4 18650 cell. If you’re not so keen on diving into assembly, we’ve seen a similar technique accomplished with a simple circuit that only wakes the microcontroller when there’s work to be done.
So where does the project go from here? Now that the PCB is largely finalized, [derflob] is turning his attention to waterproofing both it and the sensors so they can survive outside in the elements. Some kind of epoxy encapsulation is probably in order, though that will be a project for another day.
Soil moisture sensors are cheap and easy to interface with, to the point that combining one with an Arduino and blinking an LED when your potted plant is feeling a bit parched is a common beginners project. But what about on the long term? Outside of a simple proof of concept, what would it take to actually read the data from these sensors over the course of weeks or months?
That’s precisely the question [derflob] recently had to answer. The goal was to build a device that could poll multiple soil sensors and push the data wirelessly into Home Assistant. But since it would be outside on the balcony, it needed to run exclusively on battery power. Luckily his chosen platform, the ESP32, has some phenomenal power saving features. You just need to know how to use them.
The custom board can read from six soil sensors.
In his extremely detailed blog post, [derflob] goes over some of the tricks he used to eek out as much runtime as possible. The big one, and arguably the key to the whole project, is his use of the ESP32’s Ultra-Low Power coprocessor (ULP). This powerful feature allows the microcontroller to do some useful work, albeit with a reduced instruction set, without waking up the power-hungry primary processor.
Since the ULP can read from the ADC, he was able to craft some assembly code that only wakes the CPU if the readings from one of the six connected sensors has changed more than a set threshold value since the last update. This keeps the chip asleep the majority of the time, and so far, [derflob] says his board has been humming along for six months on a single LiFePO4 18650 cell. If you’re not so keen on diving into assembly, we’ve seen a similar technique accomplished with a simple circuit that only wakes the microcontroller when there’s work to be done.
So where does the project go from here? Now that the PCB is largely finalized, [derflob] is turning his attention to waterproofing both it and the sensors so they can survive outside in the elements. Some kind of epoxy encapsulation is probably in order, though that will be a project for another day.
Do you have a great application for computer vision, but couldn’t spare the cost of hardware needed to build it? Or perhaps you just need a deadline to pull you away from endless doom scrolling? Either way, the OpenCV team wants you to enter their OpenCV AI Competition 2021 and they’re willing to pitch in hardware to make it happen.
This competition is part of OpenCV’s 20th anniversary celebration, and the field of machine vision has changed a lot in those two decades. OpenCV started within Intel harnessing power of their high end CPUs, but today the excitement is around specialized acceleration hardware for vision processing. Which is why OpenCV put their support and lent their name to the OpenCV AI Kit (OAK) Kickstarter we covered a few months ago. Since then, the hardware was produced and starting to arrive in project backer’s hands. (Barring pandemic-related shipping restrictions…)
This shiny new hardware is the competition’s focus. Phase one solicits team proposals for putting an OAK-D’s power to novel use. University teams may have up to ten members, general teams are limited to four. Each team’s geographic home will put them in one of six global regions. Proposals must be submitted by January 27th, 2021. By February 11th, judges will select the best twenty-five general and ten university team proposals from each region, and every member of the team gets an OAK-D unit to turn their idea into reality by phase two deadline of June 27th. That’s up to 1,200 OAK-D modules available to anyone who can convince the judges they have a great idea and they are capable of bringing it to fruition. Is that you? Of course it is!
Teams will also receive additional resources such as an allotment of cloud compute credits to train their models, and naturally all tutorials and sample code released as part of OAK Kickstarter. No explicit resource for project team organization is mentioned, but of course our own Hackaday.io is available to support you. Best of luck to everyone who enters and we look forward to seeing all the projects this contest will bring to life.
You’ve got a machine hooked up to the Internet via a shiny new cellular modem, which you plan to administer remotely. You do a quick check on the external IP, and try and log in from another PC. Try as you might, SSH simply won’t connect. What gives?
The reality of the modern internet is that most clients no longer get their own unique IPv4 address. There simply aren’t enough to go around anymore. Instead, most telecommunications operators use Carrier Grade Network Address Translation which allows a single external address to be shared by many customers. This can get in the way of direct connection attempts from the outside world. Even if that’s not the case, most cellular operators tend to block inbound connections by default. However, there is a way around this quandary – using a VPN.
A Network That’s Private And Virtual
A VPN allows two or more systems connected to the Internet to behave as if they’re on a local network. This is useful for remote administration, particularly when working with cellular connections with restrictive traffic rules.
VPNs, or Virtual Private Networks, are exactly what they sound like. They’re a private network that exists between clients on a broader public network like the Internet. When it comes to making connections to remote hosts on cellular connections, they’re the perfect tool to get the job done. Having the remote host connect to a VPN server gets around the issue of rejected incoming connections, as all traffic goes through the VPN tunnel initiated by the remote host itself. Additionally, it means that other hosts connected to the VPN can talk to the remote host as if it’s another machine on a local network. With the correct setup, a VPN can be a highly secure and flexible way of talking to remote machines with a minimum of fuss and bluster.
You can run your own VPN server at home without much trouble. You’ll need a computer with reliable Internet access, that can accept incoming connections. Typically, this will involve enabling port forwarding on your home router so that connections made to your home IP on a particular port are forwarded to the computer running the VPN server software. Additionally, you’ll need to make sure your home internet connection isn’t behind carrier-grade NAT. Generally, if you’ve got cable, ADSL, or fiber, a simple phone call to your ISP is all that’s required. However, in some cases, you may find you have to upgrade to a higher tier connection package to get such treatment. There’s no need to have a static IP, either; dynamic DNS services can make it easy for your remote system to call back home. You can even run your own Dynamic DNS if you so desire.
So, assuming you’ve got a computer standing by, and a router with an open port to the wider internet, all you need to do is install the right software. OpenVPN is a popular choice for running a VPN server, and has all the functionality required with a bonus of being free. Historically, it’s required a significant amount of setup to install and generate all the required cryptographic certificates, however, with the release of OpenVPN Access Server, getting started is somewhat more streamlined.
Other options exist, however. PageKite is an opensource VPN solution that aims to make connecting remote systems a cinch. We’ve featured it before when discussing how to connect to Raspberry Pis from anywhere and everywhere. It’s available on a pay-what-you-want basis, with some data going through PageKite’s cloud servers to make everything that much easier to setup. Recommended pricing is just $3 USD a month, rising to $6 USD a month for more serious users. It’s a great way to get started if you just need to get your remote system talking online without a lot of unnecessary yak shaving. Another solution is WireGuard, an open-source VPN built upon concepts of ease-of-use, speed, and simplicity. With clients available for a broad base of popular operating systems, it’s easy to get up and running without a whole lot of fuss.
Once you’ve got your remote host connecting to a VPN, admin is easy. Simply enable SSH or your favored remote admin protocol, and log in as if the machine were on your local network. If your remote machine is properly configured to maintain the connection and reconnect on dropouts, you should have no issues controlling the machine no matter where it finds itself in the world – as long as it’s got a good cellular data connection. Just make sure that before you deploy it to a far flung locale, you have it to connect to the VPN on boot – else you’ll be out of luck the first time you need to command a restart.
If you’ve been following this series, you should now be confident to select the right hardware and software to control a computer remotely over the cellular network. Of course, with the roaming freedom of cellular network comes the difficulty that your remote system may end up somewhere far away and difficult to access. In the event something goes wrong, this can make solving the problem expensive and complicated. In future articles, we’ll explore ways to minimise these problems and how to best stop things from going sideways. Until then, happy hacking!
Humanoid robots always attract attention, but anyone who tries to build one quickly learns respect for a form factor we take for granted because we were born with it. Pollen Robotics wants to help move the field forward with Reachy: a robot platform available both as a product and as a wealth of information shared online.
This French team has released open source robots before. We’ve looked at their Poppy robot and see a strong family resemblance with Reachy. Poppy was a very ambitious design with both arms and legs, but it could only ever walk with assistance. In contrast Reachy focuses on just the upper body. One of the most interesting innovations is found in Reachy’s neck, a cleverly designed 3 DOF mechanism they called Orbita. Combined with two moving antennae at the top of the head, Reachy can emote a wide range of expressions despite not having much of a face. The remainder of Reachy’s joints are articulated with Dynamixel serial bus servos though we see an optional Orbita-based hand attachment in the demo video (embedded below).
Reachy’s € 19,990 price tag may be affordable relative to industrial robots, but it’s pretty steep for the home hacker. No need to fret, those of us with smaller bank accounts can still join the fun because Pollen Robotics has open sourced a lot of Reachy details. Digging into this information, we see Reachy has a Google Coral for accelerating TensorFlow and a Raspberry Pi 4 for general computation. Mechanical designs are released via web-based Onshape CAD. Reachy’s software suite on GitHub is primarily focused on Python, which allows us to experiment within a Jupyter notebook. Simulation can be done within Unity 3D game engine, which can be optionally compiled to run in a browser like the simulation playground. But academic robotics researchers are not excluded from the fun, as ROS1 integration is also available though ROS2 support is still on the to-do list.
Reachy might not be as sophisticated as some humanoid designs we’ve seen, and without a lower body there’s no way for it to dance. But we are very appreciative of a company willing to share knowledge with the world. May it spark new ideas for the future.
It’s often said that any sufficiently advanced technology is indistinguishable from magic, and when a DIY device lets you light up fluorescent bulbs with a flick of the wrist, it’s certainly not hard to see why. The latest creation from [Jay Bowles], this high voltage wand is actually a Slayer Exciter coil that’s able to boost the output of a standard 9 V alkaline or rechargeable battery high enough to perform some of the wireless power tricks we usually associate with the more complex Tesla coil.
We really can’t overstate how simple it is to build one of these yourself. Sure you’ll still need to wind the coil, but if you can chuck the 1/2 inch acrylic tube into a electric drill you should be able to make short work of it. Once you’ve wound your secondary coil from 32 gauge magnet wire, you only need a couple turns of common doorbell wire to make up the primary.
Think there must be some complex electronics hiding in the handle? Far from it. All that’s hidden by that faux-leather wrapping is a transistor to do the high-speed switching, an LED functioning as both the power indicator and the circuit’s diode, and a resistor. [Jay] put it all together dead bug style, but you could do it on a scrap of perfboard if you’d like something a little more robust.
Being a big believer in STEM education, [Jay] says the wand was designed to be as kid-friendly as possible so he could gift it to his young niece and nephew. Inspiring the next generation is certainly something we respect around these parts, though we think there’s plenty of adults who wouldn’t have been disappointed if they unwrapped a gadget like this over the holidays.
It’s often said that any sufficiently advanced technology is indistinguishable from magic, and when a DIY device lets you light up fluorescent bulbs with a flick of the wrist, it’s certainly not hard to see why. The latest creation from [Jay Bowles], this high voltage wand is actually a Slayer Exciter coil that’s able to boost the output of a standard 9 V alkaline or rechargeable battery high enough to perform some of the wireless power tricks we usually associate with the more complex Tesla coil.
We really can’t overstate how simple it is to build one of these yourself. Sure you’ll still need to wind the coil, but if you can chuck the 1/2 inch acrylic tube into a electric drill you should be able to make short work of it. Once you’ve wound your secondary coil from 32 gauge magnet wire, you only need a couple turns of common doorbell wire to make up the primary.
Think there must be some complex electronics hiding in the handle? Far from it. All that’s hidden by that faux-leather wrapping is a transistor to do the high-speed switching, an LED functioning as both the power indicator and the circuit’s diode, and a resistor. [Jay] put it all together dead bug style, but you could do it on a scrap of perfboard if you’d like something a little more robust.
Being a big believer in STEM education, [Jay] says the wand was designed to be as kid-friendly as possible so he could gift it to his young niece and nephew. Inspiring the next generation is certainly something we respect around these parts, though we think there’s plenty of adults who wouldn’t have been disappointed if they unwrapped a gadget like this over the holidays.
The availability of inexpensive electronics modules has opened up a world of opportunity for more complex projects to be completed quickly. Rather than designing everything from scratch, ready-made motor modules, regulators, computer vision modules, and control modules all ready to be put to work after arriving at one’s doorstep. Sometimes, though, these inexpensive electronics aren’t all they’re cracked up to be, so [Jan] decided to produce them from scratch instead.
[Jan] is the creator of several robots, and frequently makes use of 3.3V and 5V step down modules, but was not happy with the consistency offered by the prefab modules. The solution to this was to build them from scratch in a way that makes producing a large amount nearly as easy as ordering them. The boards are based around the SY8105 chip, and are built in two batches for the robotics shop based on the two most commonly needed output voltages. With their design they get exactly what they need every time, without worrying about reliability from a random board shop overseas.
The robotics shop is called RoboticsBrno and they have made the schematics available for anyone that wants to build their own. That being said, the design does not make considerations for low noise since it isn’t required for their use case, but if you’d prefer something simple and reliable this will get the job done. It’s also important to understand the limitations of the parts in a build that are built by a third party, although power supplies are a pretty common area to make improvements on.
When 3D pens first became available, many assumed them to be gimmicky or part of a general fad that would eventually die out. Like most revolutionary technologies, though, they’ve found a firm foothold, especially in the art community where the ability to 3D print in freehand is incredibly valuable. There are still some shortcomings with the technology, though, but [tterev3] recently tore into a 3doodler pen to make some necessary upgrades.
First, this pen has some design choices that are curious, to say the least. The cooling fan runs regardless of temperature, and it has pushbuttons for start and stop rather than a momentary button that controls the extrusion. To fix these issues, as well as change the filament size, improve the cooling, and provide greater control over the extrusion speed, [tterev3] completely rewrote the firmware, changed the microcontroller on the PCB, and made several hardware upgrades to accommodate these changes. He also went ahead and installed a USB-C port for charging, which should be standard practice on all low-voltage consumer electronics by now anyway.
The detail work on this project is impressive, given the small size of the pen itself and the amount of precision hardware needed to make the changes. Especially regarding the replacement of the microcontroller on the board itself, which is an impressive feat even without the incredibly small dimensions. The firmware upgrade is available on his GitHub page as well if you have your own 3doodler that needs modifications, and if you’re still struggling to find uses for these handy devices, we’ve seen them used with interesting effect to build drones.
LED matrixes were once a total headache, requiring careful consideration to make the most of limited I/O pins and available microcontroller resources. These days, addressable LED strings have made it all a cinch. Thus, going a little out of the box isn’t so daunting. [w.r.simpson] did just that with this hex-matrix clock.
Relying on hexes instead of a normal Cartesian grid requires some attention to how the rows and columns are laid out, but the Instructable goes through the necessary coordinate system to address the display. The whole display was built without a 3D printer, instead relying on some basic craft skills and a picture frame as the enclosure. Strips of WS2812B LEDs were used to build the hexagonal matrix, run by a Adafruit Metro Mini 328. To give each hexagonal pixel, or hexel, a crisp outline, a shadow grid was built using black paper to stop the light bleeding between the display segments when switched on. Smoked plexiglas wasn’t available, so instead, tinted window film was used to darken the front of the display.
The result is impressive; while some glue marks from the shadow grid are visible closeup, from a distance the final product looks incredibly futuristic thanks to the hexagonal layout. We can imagine this would make a great set dressing in a futuristic film clip; we fully expect to see this concept in the background of the next Ariana Grande single. If this build isn’t enough six-sided fun to sate your appetite, consider getting into Super Hexagon too!
Sand plotters are beautiful machines. They can make endless patterns, over and over again, only to wipe away their own creation with each new pass. Having seen the famous Sisyphus sand sculpture online, [Simon] decided to make his own.
The build came together quickly, thanks to [Simon]’s well-stocked workshop and experience with CNC motion platforms. The frame was built out of wood, with a combination of hand-cut and lasercut parts. After fabric-wrapping the outer rim turned out poorly, rope was substituted instead for a stylish, organic look. LEDs were installed inside to light the sand for attractive effect. The metal ball is moved through the sand via a magnet attached to an XY platform mounted on the back of the table. The platform is built out of old 3D printer parts, with a Creality CR10S Pro chosen for its ultra-quiet stepper drivers. Initial attempts to make the system near-silent were hung up by the crunching sound of the ball rolling over the sand; this was fixed by instead mounting the ball on a foam pad. While the ball is now dragged instead of rolling, the effect is one of blissful quiet instead of crunching aggravation.
The final build is incredibly attractive, and something we’d love to have as a coffee table as a conversation piece. We’ve seen [Simon]’s work around here before, too – with the water-walking RC car a particular highlight. Video after the break.
It’s 2021, shouldn’t all of our devices be able to pull the power they need from the ether? [Sasa Karanovic] certainly thinks so, which is why he recently took it upon himself to add wireless charging capabilities to his desktop computer peripherals. The Qi transmitter and receiver modules are relatively cheap and easy to come by, the trick is in getting them installed.
The keyboard gets non-invasive Qi charging.
For the keyboard, [Sasa] took the path of least resistance. The receiver coil lives inside a little 3D printed box attached to the back, and power is routed through a hacked up right-angle USB cable. It’s a simple addition that doesn’t make any permanent changes to the keyboard; perfect for those who don’t want to risk toasting their gear.
But that wasn’t really an option for the mouse. Obviously the Qi hardware would have to go on the inside, but at a glance it was clear there wasn’t enough room to mount the stock coil. So [Sasa] pulled the original coil apart and rewound it around a small 3D printed jig. This resulting coil was perfectly sized to fit inside the flat area on the left side of the mouse with no apparent degradation in charging ability. Wiring the module up to an unpopulated pad on the PCB allowed him to easily inject the 5 V output into the device’s existing charging circuitry.
It’s 2021, shouldn’t all of our devices be able to pull the power they need from the ether? [Sasa Karanovic] certainly thinks so, which is why he recently took it upon himself to add wireless charging capabilities to his desktop computer peripherals. The Qi transmitter and receiver modules are relatively cheap and easy to come by, the trick is in getting them installed.
The keyboard gets non-invasive Qi charging.
For the keyboard, [Sasa] took the path of least resistance. The receiver coil lives inside a little 3D printed box attached to the back, and power is routed through a hacked up right-angle USB cable. It’s a simple addition that doesn’t make any permanent changes to the keyboard; perfect for those who don’t want to risk toasting their gear.
But that wasn’t really an option for the mouse. Obviously the Qi hardware would have to go on the inside, but at a glance it was clear there wasn’t enough room to mount the stock coil. So [Sasa] pulled the original coil apart and rewound it around a small 3D printed jig. This resulting coil was perfectly sized to fit inside the flat area on the left side of the mouse with no apparent degradation in charging ability. Wiring the module up to an unpopulated pad on the PCB allowed him to easily inject the 5 V output into the device’s existing charging circuitry.
We don’t know why, but for some reason, the more dangerous something is, the more hacker appeal it seems to have. We like to deal with high temperatures, high voltages, dangerous chemicals, and powerful lasers. So [Tech Ingredient’s] recent video about homemade rocket motors certainly caught our attention. You may need a little commitment, though. The first video (yes, there isn’t just one) is over an hour long.
Turns out, [Tech] doesn’t actually want to use the rockets for propulsion. He needed a source of highly-ionized high-velocity plasma to try to get more power from his magnetohydrodynamic project. Whatever you want to use it for, these are serious-sized motors. [Tech] claims that his design is both powerful and easy to build. He also has a “secret” rocket fuel that he shares. What is it? We won’t spoil the video for you, but it is a sweet surprise.
The video isn’t just a how-to. There is a lot of discussion about how rocket motors work, which isn’t as intuitive as you might think. Of course, when you build rockets, weight is everything. There’s generous use of epoxy to provide strong barriers and seals without a lot of weight. If you just want to see the pyrotechnics, you can start with the second video — a smaller investment at less than 12 minutes.
The largest motor was roughly an H-class motor, which is very powerful. A top-end commercially available model rocket engine is usually an F-class and each letter is double the amount of thrust, so these are serious size motors.
Addressable LED strips, most commonly using the WS2812B, have revolutionized the pursuit of the glowiest and flashiest of builds. No longer does a maker have to compromise on full RGB color or number of LEDs due to the limitations of their chosen microcontroller, or fuss around with multiplexing schemes. However, the long strips of bright LEDs do have an issue with voltage drop on long runs, leading to dimming and color irregularities. Thankfully, [Jan Mrázek] has come up with a useful solution in the form of the Neopixel Booster.
The device consists of a small PCB which packs a 5 volt regulator capable of putting out up to 4 amps. It’s designed with pads that match typical Neopixel strips, such that it can be neatly soldered in every 50cm or every 60 LEDs or so. Each booster PCB is fed with a set of fat power wires, at between 6-18 volts. This allows electricity to be fed to the full length of the strip at higher voltage, and thus lower current, greatly reducing resistive power losses. By having several regulators along the length of the strip, it helps guarantee that the whole length of a long run is receiving plenty of voltage and current and can light up the correct color as desired.
It’s a well thought out solution to a frustrating problem, and [Jan’s] efforts on the design front mean that a 5 meter long waterproof strip can be converted in around about an hour. We can imagine this could be manufactured into strips in future, too. If you’re wondering what to do with all those LEDs, consider making yourself a custom display.
While rocket boosts were out of scope for this build, [mrak_ripple] was pretty confident he could build a jumping, flipping RC car modelled after the Rocket League Octane vehicle. Initial experiments involved a custom 3D printed spring mechanism, but the results were underwhelming. Instead, in the true hacker spirit, a jumping mechanism was taken from an existing toy, and installed in the car instead. This was combined with a mechanism built out of a brushless motor with a flywheel added to generate a flipping moment in mid-air.
While rocket boosts were out of scope for this build, [mrak_ripple] was pretty confident he could build a jumping, flipping RC car modelled after the Rocket League Octane vehicle. Initial experiments involved a custom 3D printed spring mechanism, but the results were underwhelming. Instead, in the true hacker spirit, a jumping mechanism was taken from an existing toy, and installed in the car instead. This was combined with a mechanism built out of a brushless motor with a flywheel added to generate a flipping moment in mid-air.
While rocket boosts were out of scope for this build, [mrak_ripple] was pretty confident he could build a jumping, flipping RC car modelled after the Rocket League Octane vehicle. Initial experiments involved a custom 3D printed spring mechanism, but the results were underwhelming. Instead, in the true hacker spirit, a jumping mechanism was taken from an existing toy, and installed in the car instead. This was combined with a mechanism built out of a brushless motor with a flywheel added to generate a flipping moment in mid-air.
