Join us on Wednesday, February 3 at noon Pacific for the Mechanical Timekeeping Hack Chat with Clickspring!

The reckoning of the passage of time has been of vital importance to humans pretty much for all our history, but for most of that time we were stuck looking at the movements of heavenly bodies or noting the changing of the seasons to answer questions of time. The search for mechanical aids to mark the passage of time began surprisingly early, though, pretty much from the time our ancestors first learned to work with metals.

Timekeeping devices were often created to please a potentate or to satisfy a religious imperative, but whatever the reason for their invention, these early clocks and calendars were key to a ton of discoveries. Timekeeping devices were among the first precision mechanisms, and as such formed the basis of much of our mechanical world. A mechanical representation of the passage of time also gave us some of the first precise observations of the physical world, which led to an enormous number of discoveries about the nature of the universe, not to mention practical skills such as navigation, which allowed us to explore the world with greater confidence.

In our era, precision timekeeping has moved beyond the mechanical realm into the subatomic world, and mechanisms built to please a prince are relegated to museums and collectors. That’s not to say there isn’t plenty to learn from the building of mechanical timepieces, as anyone who has watched any of the videos on Clickspring’s YouTube channel can attest. Clickspring not only makes some magnificent modern timepieces, like his famous open-frame clock, but recently he’s also branched out into the timekeeping mechanisms of the ancients. He built a reproduction Byzantine sundial-calendar, and tackled a reproduction of the famous Antikythera mechanism. The latter was undertaken using only the tools and materials that would have been available to the original maker. That led to an unexpected discovery and a detour into the world of scholarly publishing.

Clickspring has been busy lately, but he made some time to stop by the Hack Chat and talk about mechanical timepieces. We’ll talk about his modern builds, his forays into the mechanisms of antiquity, and his serendipitous discovery. On the way we’re likely to talk about what it takes to build precision mechanisms in a small shop, and whatever else that crops up.

Our Hack Chats are live community events in the Hackaday.io Hack Chat group messaging. This week we’ll be sitting down on Wednesday, February 3 at 12:00 PM Pacific time. If time zones have you tied up, we have a handy time zone converter.

Click that speech bubble to the right, and you’ll be taken directly to the Hack Chat group on Hackaday.io. You don’t have to wait until Wednesday; join whenever you want and you can see what the community is talking about.

source https://hackaday.com/2021/02/01/mechanical-timekeeping-hack-chat-with-clickspring/

Join us on Wednesday, February 3 at noon Pacific for the Mechanical Timekeeping Hack Chat with Clickspring!

The reckoning of the passage of time has been of vital importance to humans pretty much for all our history, but for most of that time we were stuck looking at the movements of heavenly bodies or noting the changing of the seasons to answer questions of time. The search for mechanical aids to mark the passage of time began surprisingly early, though, pretty much from the time our ancestors first learned to work with metals.

Timekeeping devices were often created to please a potentate or to satisfy a religious imperative, but whatever the reason for their invention, these early clocks and calendars were key to a ton of discoveries. Timekeeping devices were among the first precision mechanisms, and as such formed the basis of much of our mechanical world. A mechanical representation of the passage of time also gave us some of the first precise observations of the physical world, which led to an enormous number of discoveries about the nature of the universe, not to mention practical skills such as navigation, which allowed us to explore the world with greater confidence.

In our era, precision timekeeping has moved beyond the mechanical realm into the subatomic world, and mechanisms built to please a prince are relegated to museums and collectors. That’s not to say there isn’t plenty to learn from the building of mechanical timepieces, as anyone who has watched any of the videos on Clickspring’s YouTube channel can attest. Clickspring not only makes some magnificent modern timepieces, like his famous open-frame clock, but recently he’s also branched out into the timekeeping mechanisms of the ancients. He built a reproduction Byzantine sundial-calendar, and tackled a reproduction of the famous Antikythera mechanism. The latter was undertaken using only the tools and materials that would have been available to the original maker. That led to an unexpected discovery and a detour into the world of scholarly publishing.

Clickspring has been busy lately, but he made some time to stop by the Hack Chat and talk about mechanical timepieces. We’ll talk about his modern builds, his forays into the mechanisms of antiquity, and his serendipitous discovery. On the way we’re likely to talk about what it takes to build precision mechanisms in a small shop, and whatever else that crops up.

Our Hack Chats are live community events in the Hackaday.io Hack Chat group messaging. This week we’ll be sitting down on Wednesday, February 3 at 12:00 PM Pacific time. If time zones have you tied up, we have a handy time zone converter.

Click that speech bubble to the right, and you’ll be taken directly to the Hack Chat group on Hackaday.io. You don’t have to wait until Wednesday; join whenever you want and you can see what the community is talking about.

source https://hackaday.com/2021/02/01/mechanical-timekeeping-hack-chat-with-clickspring/

Ah, the charm of candlelight! Nothing says “romance” — or “extended power outage” — like the warm, soft glow of a real candle. But if you’re not a fan of burning wax for whatever reason, this electric plasma candle may be just the thing to build for your next dinner for two.

This re-imagining of the humble candle comes to us by way of plasma super-fan [Jay Bowles], who has a lot of experience with plasmas and the high-voltage circuits that often go along with them. Even so, he had to enlist help with the circuit, with is essentially a 10-MHz Class-E oscillator, from [Leon] at the Teslaundmehr channel on YouTube. The most prominent feature of the build is the big resonator coil, surrounded by the shorter primary coil and sitting atop the heatsink for the MOSFET driver. [Jay]’s usual acrylic-rich style is well represented here, and the resulting build is quite lovely.

The tuning process, though, sounds like it was pure torture. It took a lot of tweaking — and a lot of MOSFETs — to get the candle to produce a stable flame. But once it did, the results were striking. The plasma coming off the breakout point on the resonator coil is pretty much the same size, shape, and — occasionally — the color as a candle flame. It’s also hot enough to do some damage, so do be careful if you build this. We’ve included both [Jay]’s and [Leon]’s videos below; [Leon]’s has great step-by-step build instructions.

We’ve been following [Jay]’s journey through the plasmaverse for a while now, from his cheap and simple Tesla coils to using corona discharge to clean his hands. He even hosted a Hack Chat on the subject last year.

source https://hackaday.com/2021/02/01/electric-candle-replaces-flame-with-plasma/

Hackers and makers can sometimes feel like they’re getting the short end of the stick when it comes to gift giving. You’re out there making thoughtful, intricate circuit sculptures, helpful software, or face masks for people, and what do you get in return? Okay, yes, usually gift cards or tools or other things that feed your creativity in the first place. But darn it, it would be nice to receive a handmade gift once in a while, right?

So here’s what you do: make friends with enough other makers that you find your birthday twin, or close enough that you both feel the warmth of the personal holiday you share. Then you get them to agree to trade handmade birthday presents with you. That’s more or less what happened between [Becky Stern] and [Estefannie], who seem to have found each other through the magic of sharing projects on YouTube.

[Becky]’s gift to [Estefannie] is a busy intersection of maker elements including graphic design, embroidery, electronics, and 3D printing. [Becky] started with the embroidery, which was made possible thanks to a new open-source library for Processing called PEmbroider. Once that was done, she 3D printed the frame and added the electronics — candle flicker LEDs for the birthday cake, and a handful of songs that are accessible via touch contacts screwed into the side of the frame. [Becky] added a real-time clock module so it plays a few extra songs on [Estefannie]’s actual birthday.

The most thoughtful element here is personalization, and it’s amazing what can happen when you put 100% of yourself into something that is 100% about someone else. Every bit of the art is personal to [Estefannie], and every atom of the build is pure [Becky]. Check out the demo and build video and see what [Estefannie] made for [Becky] after the break.

[Becky]’s varied creativity has graced these pages many times before. See how she bid adieu to 2020, built a daily affirmation mirror, and gave a mask-making masterclass in the early stages of the pandemic.

source https://hackaday.com/2021/02/01/electronic-embroidery-birthday-card-is-a-celebration-of-skills/

Being an editor is a job that seems deceptively easy until you are hauled over the coals for letting a textual howler go to print (or website). Most publications have style guides to ensure that their individual voice is preserved, but even the most eagle-eyed will sometimes slip up in their application. At the Guardian newspaper in the UK they have been struggling with this against an ever-evolving style guide that must adapt to fast-moving world events, to the extent that they had a set of regular expressions to deal with commonly-occurring problems. A lot of regular expressions, in fact around 13,000 of them.

Clearly some form of management was required, and  a team of developers set about taming this monster. The result is Typerighter, their server-side document-checker, which can be found in a GitHub repository. Surprisingly for rule management they started with a Google Sheet, a choice which proved unexpectedly robust when working with such a long list even though they later replaced it. The back end doing the job of text matching was written in Scala, and for the front end a plugin was created for their Prosemirror text editor.

For a publication of course this is extremely interesting, but where’s the interest for hackers? The answer lies in any text-processing engine that uses a lot of regular expressions; those of you who have dabbled in this space will know how unwieldy this work can become. Any user of computational linguistic techniques in the pursuit of language processing could probably find much of interest here.

If you’re a bit hazy on regular expressions, how about the episode on them from our long-running Linux-fu series?

source https://hackaday.com/2021/02/01/13000-regular-expressions-make-an-editors-life-easier/

We doubt you’ll be driving a Bugatti Bolide anytime soon. It’s a bit of a showy concept car, and it really is pushing some limits on what you can 3D print in an automobile. As you can imagine, they aren’t printing car parts out of ABS or PLA. According to The Drive, the prints use selective laser melting with titanium to make some impressively strong and light parts.

It isn’t just the material that makes the 3D prints strong. Bugatti actually patented the internal structure of some parts which are almost bone-like. By having the parts largely hollow, the weight is cut. But fine internal structure creates very strong parts. How strong? A 3.52 ounce pushrod can handle up to 3.85 tons. The printed titanium is apparently heat-treated to increase its resistance to fracture strains.

In addition to titanium, some of the concept car’s parts are printed ceramic which insulates some components from heat. The printing process can apparently get resolutions down to 0.1 mm. Many parts are quite lightweight including a 0.48 mm wheel that with supports weighs in at about 100 grams.

If you want to get into having a project car, we’d suggest something more modest. Even if you want to 3D print a titanium part for your ride, we’d still start a little smaller.

source https://hackaday.com/2021/01/31/bugatti-concept-car-shows-3d-printed-strength/

There are an awful lot of machines on the market these days that fall under the broad category of “cheap Chinese laser cutters”. You know the type — the K40s, the no-name benchtop CO2 cutters, the bigger floor-mount units. If you’ve recently purchased one of these machines from one of the usual vendors, or even if you’re just thinking about doing so, you’ll likely have some questions. In which case, this “Chinese Laser Cutters 101” online class might be right up your alley. We got wind of this though its organizer, Jonathan Schwartz of American Laser Cutter in Los Angeles, who says he’s been installing, repairing, and using laser cutters for a decade now. The free class will be on February 8 at 5:00 PM PST, and while it’s open to all, it does require registration.

We got an interesting tip the other day that had to do with Benford’s Law. We’d never heard of this one, so we assumed was a “joke law” like Murphy’s Law or Betteridge’s Rule of Headlines. But it turns out that Benford’s Law describes the distribution of leading digits in large sets of numbers. Specifically, it says that the leading digit in any given number is more likely to be one of the smaller numbers. Measurements show that rather than each of the nine base 10 digits showing up about 11% of the time, a 1 will appear in the leading digit 30% of the time, while a 9 will appear about 5% of the time. It’s an interesting phenomenon, and the tip we got pointed to an article that attempted to apply Benford’s Law to image files. This technique was used in a TV show to prove an image had been tampered with, but as it turns out, Hollywood doesn’t always get technical material right. Shocking, we know, but the technique was still interesting and the code developed to Benford-ize image files might be useful in other ways.

Everyone knew it was coming, and for a long time in advance, but it still seems that the once-and-for-all, we’re not kidding this time, it’s for realsies shutdown of Adobe Flash has had some real world consequences. To wit, a railroad system in the northern Chinese city of Dalian ground to a halt earlier this month thanks to Flash going away. No, they weren’t using Flash to control the railroad, but rather it was buried deep inside software used to schedule and route trains. It threw the system into chaos for a while, but never fear — they got back up and running by installing a pirated version of Flash. Here’s hoping that they’re working on a more permanent solution to the problem.

First it was toilet paper and hand sanitizer, now it’s…STM32 chips? Maybe, if the chatter on Twitter and other channels is to be believed. Seems like people are having a hard time sourcing the microcontroller lately. It’s all anecdotal so far, of course, but the prevailing theory is that COVID-19 and worker strikes have lead to a pinch in production. Plus, you know, the whole 2020 thing. We’re wondering if our readers have noticed anything on this — if so, let us know in the comments below.

And finally, just because it’s cool, here’s a video of what rockets would look like if they were transparent. Well, obviously, they’d look like twisted heaps of burning wreckage on the ground is they were really made with clear plastic panels and fuel tanks, but you get the idea. The video launches a virtual fleet — a Saturn V, a Space Shuttle, a Falcon Heavy, and the hypothetical SLS rocket — and flies them in tight formation while we get to watch their consumables be consumed. If the burn rates are accurate, it’s surprising how little fuel and oxidizer the Shuttle used compared to the Saturn. We were also surprised how long the SLS holds onto its escape tower, and were pleased by the Falcon Heavy payload reveal.

source https://hackaday.com/2021/01/31/hackaday-links-january-31-2021/

Outputting data from a microcontroller over a serial port is convenient and easy, but formatting, visualizing, and analyzing the data can be tedious and frustrating. [Alex Spataru] knows this all too well, having spent too many hours building and debugging custom dashboards. To save himself and others the same frustration in the future, he created Serial Studio, a tool for quickly building dashboards for serial data.

The only input required for Serial Studio to create a dashboard is a simple JSON structure specifying the data’s format, and how it should be grouped and displayed. Originally Serial Studio required all the JSON data to be sent over serial, which is fine for simple data but quickly becomes cumbersome for more complex applications. To solve this, [Alex] added a feature allowing the JSON document with the format information loaded from the computer, while only the data is sent over serial.

Serial Studio includes several visualization options, including raw line graphs, bar/level indicator, dial indicator, the artificial horizon for IMU data, or a map widget. It can also output the formatted data to a CSV file for further analysis in other software. A console window is also included for viewing raw data or debugging purposes. See the usage demo after the break.

We like Serial Studio’s ease of use and adaptability, and we’ll likely use it for our own projects in the future. It is compatible with Linux, Windows, and Mac thanks to the Qt framework, and the code is open-source and available on GitHub.

If you’ve ever watched one of the BPS.Space model rocket launch videos, you’ll know how critical data logging, visualization and analysis is for [Joe Barnard]’s work. Serial Studio is perfect for such applications, and [Alex] used it extensively for simulated satellite competitions at his university.

source https://hackaday.com/2021/01/31/serial-studio-easily-visualise-and-log-serial-data/

Using vision technology to identify weeds in agriculture is an area of active development, and a team of researchers recently shared their method of using a combination of machine vision plus depth information to identify and map weeds with the help of OpenCV, the open-source computer vision library. Agriculture is how people get fed, and improving weed management is one of its most important challenges.

Many current efforts at weed detection and classification use fancy (and expensive) multispectral cameras, but PhenoCV-WeedCam relies primarily on an OAK-D stereo depth camera. The system is still being developed, but is somewhat further along than a proof of concept. The portable setups use a Raspberry Pi, stereo camera unit, power banks, an Android tablet for interfacing, and currently require an obedient human to move and point them.

It’s an interesting peek at the kind of hands-on work that goes into data gathering for development. Armed with loads of field data from many different environments, the system can use the data to identify grasses, broad leaf plants, and soil in every image. This alone is useful, but depth information also allows the system to estimate overall plant density as well as try to determine the growth center of any particular plant. Knowing that a weed is present is one thing, but to eliminate it with precision — for example with a laser or mini weed whacker on a robot arm — knowing where the weed is actually growing from is an important detail.

PhenoCV-WeedCam (GitHub repository) is not yet capable of real-time analysis, but the results are promising and that’s the next step. The system currently must be carried by people, but could ultimately be attached to a robotic platform made specifically to traverse fields.

source https://hackaday.com/2021/01/31/opencv-and-depth-camera-spots-weeds/

Measuring the usage of domestic utilities such as water, gas or electricity usually boils down to measuring a repetitive pulse signal with respect to time. To make things easy, most modern utility meters have a pulsed LED output, which can be used to monitor the consumption by using an external optical sensor. But what do you do if your meter isn’t so cooperative?

That’s exactly what [Francesco] had to figure out while developing the non-invasive gas tracking system he calls ESPmeter. His meter might not have an LED, but it did have a magnet attached to the counter disk which activated an internal hall sensor. With some hacking, he was able to attach an external Hall-effect sensor to pick up this magnet and use the signal to monitor his daily gas consumption.

A big stumbling block in such projects is the issue of powering the device for an extended period, and remembering when it’s time to change the batteries. With the clever use of commonly available parts, he was able to reduce power consumption allowing three AA batteries to last about a year between changes. For one thing, he uses an ATtiny13 to actually read the sensor values. The chip doesn’t run continuously, its watchdog is set at 1 Hz, ensuring that the device is woken up often enough so that it has time to power up the sensor and detect the presence of the magnet. Battery voltage is also measured via a voltage divider connected to the chip’s ADC pin.

At regular intervals throughout the day, the ESP8266 polls the ATtiny13 to pull the stored sensor pulses and voltage measurement. Then at midnight, the ESP transmits all the collected data to a remote server. Overall, this whole scheme allows [Francesco] to reliably gather his gas consumption data while not having to worry about batteries until he gets the low voltage notification. Since the data visualization requirements are pretty basic, he is keeping things simple by using Plotly to display his time series data.

If you are unfortunate enough to have an even older meter which doesn’t use optical or magnetic rotation sensing, you can use a disassembled mouse to keep track of the Gas Meter.

source https://hackaday.com/2021/01/31/old-gas-meter-gets-smart-with-the-esp8266/

Measuring the usage of domestic utilities such as water, gas or electricity usually boils down to measuring a repetitive pulse signal with respect to time. To make things easy, most modern utility meters have a pulsed LED output, which can be used to monitor the consumption by using an external optical sensor. But what do you do if your meter isn’t so cooperative?

That’s exactly what [Francesco] had to figure out while developing the non-invasive gas tracking system he calls ESPmeter. His meter might not have an LED, but it did have a magnet attached to the counter disk which activated an internal hall sensor. With some hacking, he was able to attach an external Hall-effect sensor to pick up this magnet and use the signal to monitor his daily gas consumption.

A big stumbling block in such projects is the issue of powering the device for an extended period, and remembering when it’s time to change the batteries. With the clever use of commonly available parts, he was able to reduce power consumption allowing three AA batteries to last about a year between changes. For one thing, he uses an ATtiny13 to actually read the sensor values. The chip doesn’t run continuously, its watchdog is set at 1 Hz, ensuring that the device is woken up often enough so that it has time to power up the sensor and detect the presence of the magnet. Battery voltage is also measured via a voltage divider connected to the chip’s ADC pin.

At regular intervals throughout the day, the ESP8266 polls the ATtiny13 to pull the stored sensor pulses and voltage measurement. Then at midnight, the ESP transmits all the collected data to a remote server. Overall, this whole scheme allows [Francesco] to reliably gather his gas consumption data while not having to worry about batteries until he gets the low voltage notification. Since the data visualization requirements are pretty basic, he is keeping things simple by using Plotly to display his time series data.

If you are unfortunate enough to have an even older meter which doesn’t use optical or magnetic rotation sensing, you can use a disassembled mouse to keep track of the Gas Meter.

source https://hackaday.com/2021/01/31/old-gas-meter-gets-smart-with-the-esp8266/

Measuring the usage of domestic utilities such as water, gas or electricity usually boils down to measuring a repetitive pulse signal with respect to time. To make things easy, most modern utility meters have a pulsed LED output, which can be used to monitor the consumption by using an external optical sensor. But what do you do if your meter isn’t so cooperative?

That’s exactly what [Francesco] had to figure out while developing the non-invasive gas tracking system he calls ESPmeter. His meter might not have an LED, but it did have a magnet attached to the counter disk which activated an internal hall sensor. With some hacking, he was able to attach an external Hall-effect sensor to pick up this magnet and use the signal to monitor his daily gas consumption.

A big stumbling block in such projects is the issue of powering the device for an extended period, and remembering when it’s time to change the batteries. With the clever use of commonly available parts, he was able to reduce power consumption allowing three AA batteries to last about a year between changes. For one thing, he uses an ATtiny13 to actually read the sensor values. The chip doesn’t run continuously, its watchdog is set at 1 Hz, ensuring that the device is woken up often enough so that it has time to power up the sensor and detect the presence of the magnet. Battery voltage is also measured via a voltage divider connected to the chip’s ADC pin.

At regular intervals throughout the day, the ESP8266 polls the ATtiny13 to pull the stored sensor pulses and voltage measurement. Then at midnight, the ESP transmits all the collected data to a remote server. Overall, this whole scheme allows [Francesco] to reliably gather his gas consumption data while not having to worry about batteries until he gets the low voltage notification. Since the data visualization requirements are pretty basic, he is keeping things simple by using Plotly to display his time series data.

If you are unfortunate enough to have an even older meter which doesn’t use optical or magnetic rotation sensing, you can use a disassembled mouse to keep track of the Gas Meter.

source https://hackaday.com/2021/01/31/old-gas-meter-gets-smart-with-the-esp8266/

One of the essentials on the bench is some form of hot air gun. Whether it’s a precision tool intended for reworking PCBs or the broad-stroke item used for paint stripping, we’ve all got one somewhere. The paint-stripping variety are pretty cheap, but not as cheap as [Porcas Pregos e Parafusos]’s home made hot air gun. This slightly hair-raising device is made from a variety of junk parts and delivers hot air, though we suspect the possibility for burning the operator remains high.

At its heart is one of those mains powered water boiler elements designed to be lowered into a cup or similar, and since such devices would burn out if not cooled in some way, there is a fan from a microwave oven passing air over it. The whole thing sits inside an aluminium cone cut from a circular cake tin, and is held together on a wooden chassis to which the handle and power switch from a defunct electric drill provide the operator with something to hold on to.

As you can see from the video below the break it makes for an effective hot air gun, but one that we’re guessing you’d soon learn to avoid touching on the metal cone. Still, as a community we’re used to this with our soldering irons, as the RevSpace T-shirt puts it: “If it smells like chicken, you’re holding it wrong“.

Strangely, this isn’t the first DIY heat gun we’ve seen.

Thanks [Danjovic] for the tip.

source https://hackaday.com/2021/01/31/this-hot-air-gun-is-either-a-work-of-genius-or-lethal-we-cant-decide/

[CuriousMarc] likes to go to surplus stores even though there are fewer of them around. On a recent trip, he found a box that had some parts he thought would work for a temperature controller project. It was marked Dial-A-Level and proudly proclaimed that it had a patent pending. The box was from the 1970s and [Marc] was wondering what the device was meant to do.

The device was a bit of a puzzle since it had three oddly-marked probe inputs. A search through the patent database revealed the device was a “capacitance probe for detecting moisture with very long cables.” The idea was to create a capacitor at the end of the cable and use the liquid as a dielectric. The sensor creates a 10 kHz sine wave it uses to excite the probe and an op amp measures the relative capacitive reactance of the probe versus a reference capacitor. The rest of the circuit is a comparator that reacts when the level is at a threshold.

We love seeing the old hand-drawn boards from that era. Component designations are in copper and there’s no solder mask visible. There was a clever application of a silicon controlled rectifiers and a relay to create a type of flip flop, that [Marc] explains.

Interestingly, the company that made the device, Expo Instruments, is still around and [Marc] contacted them. The actual patent holder replied and was amazed that [Marc] had possession of this antique. You can only wonder if anything you build today will wind up on whatever passes for YouTube three or four decades from now.

Capacitive sensing is quite versatile. Of course, there are many other ways to sense liquid level, too.

source https://hackaday.com/2021/01/31/mystery-box-gives-up-its-patented-secrets/

It’s an age-old problem. You draw up a nice 6.5-meter long motorboat and then discover the shape won’t allow for a fiberglass mold. What do you do? If you’re [Moi], you grab a few Kuka robots and 3D print it using thermoplastic with embedded glass fibers. A UV light cures the plastic and you wind up with printed fiberglass. That’s the story behind the MAMBO, a 3D printed powerboat.

Despite the color, the fiberglass isn’t blue out of the gate — the boat is painted. Still, it looks nice with lines inspired by [Sonny Levi]’s Arcidiavolo design from 1973. MAMBO stands for Motor Additive Manufacturing BOat. It has a dry weight of about 800 kg and is fitted with a cork floor, white leather seats, and an engine. We presume none of those things were 3D printed.

Although it wasn’t fiberglass, we’ve seen a 3D printed boat before. In particular, the University of Maine’s giant 22,000 square foot printer cranked one out. We’ve also seen boats printed in standard PLA filament, which then had fiberglass cloth and resin applied after printing. True that one was only RC, but there’s no reason the concept couldn’t be scaled up if you had the patience.

source https://hackaday.com/2021/01/30/3d-printing-a-full-scale-fiberglass-speedboat/

[memestra] is a teacher whose life has become a series of videoconferences over the last year or so. With all the classes and meetings, they spend the whole day switching between either Zoom, Teams, or Meet. If anyone needs a single piece of hardware to control them all, it’s [memestra]. Well, and every other teacher out there.

The hardware — an Arduino Pro Micro and some buttons — should come as no surprise, except for maybe [memstra]’s use of a resistor network for the LEDs. Still, there’s a lot to like about this little box, starting with the enclosure. That’s not milled or laser-cut metal — each side is a PCB, and they’re all soldered together into a box.

We especially like the top panel, which fits down over the PCB that all the components are soldered to. Each of the non-volume buttons has multiple functions that are accessed by pressing, long pressing, or double pressing. But even the volume buttons do double duty: press them together to mute and un-mute. If [memestra] ever forgets which button does what and how, there’s a handy reference table silkscreened on the bottom panel.

In true teacher fashion, [memestra] has written comprehensive instructions for anyone looking to build a similar device. The heavily-commented code should make it a cinch to drop in keyboard shortcuts for Discord or anything else you might be using, though it’s worth noting that this box is optimized for the desktop apps and not the browser-based versions.

Just looking for a fun way to end video calls? Pull chains are pretty fun.

source https://hackaday.com/2021/01/30/master-video-call-control-panel-is-made-of-pcbs/

[memestra] is a teacher whose life has become a series of videoconferences over the last year or so. With all the classes and meetings, they spend the whole day switching between either Zoom, Teams, or Meet. If anyone needs a single piece of hardware to control them all, it’s [memestra]. Well, and every other teacher out there.

The hardware — an Arduino Pro Micro and some buttons — should come as no surprise, except for maybe [memstra]’s use of a resistor network for the LEDs. Still, there’s a lot to like about this little box, starting with the enclosure. That’s not milled or laser-cut metal — each side is a PCB, and they’re all soldered together into a box.

We especially like the top panel, which fits down over the PCB that all the components are soldered to. Each of the non-volume buttons has multiple functions that are accessed by pressing, long pressing, or double pressing. But even the volume buttons do double duty: press them together to mute and un-mute. If [memestra] ever forgets which button does what and how, there’s a handy reference table silkscreened on the bottom panel.

In true teacher fashion, [memestra] has written comprehensive instructions for anyone looking to build a similar device. The heavily-commented code should make it a cinch to drop in keyboard shortcuts for Discord or anything else you might be using, though it’s worth noting that this box is optimized for the desktop apps and not the browser-based versions.

Just looking for a fun way to end video calls? Pull chains are pretty fun.

source https://hackaday.com/2021/01/30/master-video-call-control-panel-is-made-of-pcbs/

[memestra] is a teacher whose life has become a series of videoconferences over the last year or so. With all the classes and meetings, they spend the whole day switching between either Zoom, Teams, or Meet. If anyone needs a single piece of hardware to control them all, it’s [memestra]. Well, and every other teacher out there.

The hardware — an Arduino Pro Micro and some buttons — should come as no surprise, except for maybe [memstra]’s use of a resistor network for the LEDs. Still, there’s a lot to like about this little box, starting with the enclosure. That’s not milled or laser-cut metal — each side is a PCB, and they’re all soldered together into a box.

We especially like the top panel, which fits down over the PCB that all the components are soldered to. Each of the non-volume buttons has multiple functions that are accessed by pressing, long pressing, or double pressing. But even the volume buttons do double duty: press them together to mute and un-mute. If [memestra] ever forgets which button does what and how, there’s a handy reference table silkscreened on the bottom panel.

In true teacher fashion, [memestra] has written comprehensive instructions for anyone looking to build a similar device. The heavily-commented code should make it a cinch to drop in keyboard shortcuts for Discord or anything else you might be using, though it’s worth noting that this box is optimized for the desktop apps and not the browser-based versions.

Just looking for a fun way to end video calls? Pull chains are pretty fun.

source https://hackaday.com/2021/01/30/master-video-call-control-panel-is-made-of-pcbs/

We like to feature hacks that are affordable and accessible to the average person, but from time to time it’s fun to dream about the projects we’ll tackle when we’re all grown up and stinking rich. [Mike Patey] appears to fall rather comfortably in the latter category, but thankfully he hasn’t lost his “excited kid with big plans” spirit. A talented and experienced experimental aircraft builder, he’s currently working on Scrappy, a small bush plane built to be a short take-off and landing drag racer.

Scrappy started life as a Carbon Cub, a modernized kit version of the venerable Piper Super Cub. The only thing left of the original plane is a part of the fuselage frame, with almost everything else being custom. The engine is a 780 cubic inch (13 liter) horizontally opposed 8-cylinder, scavenged from one of [Mike]’s racing planes, and fitting it required extensive structural changes to the fuselage. The paddle-like propeller was intended for an airboat, and is designed for high thrust at low speeds. The skin of the aircraft is all carbon fiber, and the suspension almost looks like it’s borrowed from an off-road racing truck. [Mike] also added (and test fired) a ballistic recovery parachute. The cockpit instruments are also over-the-top for an aircraft like this, with seven Garmin multi-function displays.

Scrappy is still missing its wings, which will also be heavily modified. From the oil-cooling system to the door latch and gust-lock for the stick, everything was designed and made by [Mike]. We’re enjoying the in-depth build videos that show how he tackles all the little challenges that pop-up in such an ambitious project.

[Mike] made a name for himself with his previous monster bush plane Draco, which was sadly destroyed during an ill-considered take-off last year. Fortunately nobody was harmed in the incident, and Draco became a part donor for Scrappy. If budget planes are more your style, check out [Peter Sripol]’s latest electric microlight.

source https://hackaday.com/2021/01/30/scrappy-drag-racing-bush-plane/

It’s the middle of winter for those of us who live in the Northern Hemisphere, which naturally turns minds towards heating, or sometimes the lack of it. It’s particularly difficult for those who rely on a wood stove to escape the feeling that perhaps most of that hard-won heat may be whistling up the chimney rather than keeping them warm. It’s a problem [Lou] has addressed with his DIY chimney heat reclaimer.

As can be seen from the video below the break, his stove appears to be in a workshop, and has a long single-wall metal stove pipe. Over the outside of this he’s placed a pair of T pieces joined by a longer length of pipe all of a larger bore, and a mains-powered fan forces air through this air jacket. The result is a continuous flow of hot air that he claims delivers a 45% heat reclamation. We’re curious though whether the reduction in flue temperature might cause extra tar condensation and thus the build-up of flammable material further up the chimney. The stove itself is a double barrel affair with access for smoking, and the video describing it is worth a look in itself.

Whatever the stove, be sure to ensure a constant supply of fuel!

source https://hackaday.com/2021/01/30/a-heat-reclaimer-for-your-woodstove-the-one-thing-its-not-is-cool/

For the impatient Nissan owners who may be joining us from Google, a hacker by the name of [ea] has figured out how to get a root shell on the Bosch LCN2kai head unit of their 2015 Xterra, and it looks like the process should be the same for other vehicles in the Nissan family such as the Rogue, Sentra, Altima, and Frontier. If you want to play along at home, all you have to do is write the provided image to a USB flash drive and insert it.

Now for those of us who are a more interested in how this whole process works, [ea] was kind of enough to provide a very detailed account of how the exploit was discovered. Starting with getting a spare Linux-powered head unit out of a crashed Xterra to experiment with, the write-up takes the reader through each discovery and privilege escalation that ultimately leads to the development of a non-invasive hack that doesn’t require the user to pull their whole dashboard apart to run.

The early stages of the process will look familiar to anyone who’s messed with embedded Linux hacking. The first step was to locate the board’s serial port and connect it to the computer. From there, [ea] was able to change the kernel parameters in the bootloader to spawn an interactive shell. To make things a little easier, the boot scripts were then modified so the system would start up an SSH server accessible over a USB Ethernet adapter. With full access to the system, the search for exploits could begin.

After some poking, [ea] discovered the script designed to mount USB storage devices had a potential flaw in it. The script was written in such a way that the filesystem label of the device would be used to create the mount point, but there were no checks in place to prevent a directory traversal attack. By crafting a label that read ../../usr/bin/ and placing a Bash script on the drive, it’s possible to run arbitrary commands on the head unit. The provided script permanently adds SSHd to the startup process, so when the system reboots, you’ll be able to log in and explore.

So what does [ea] want to do with this new-found exploit? It looks like the goal is to eventually come up with some custom programs that extend the functionality of the in-dash Linux system. As it seems like these “infotainment” systems are now an inescapable feature of modern automobiles, we’re certainly excited to see projects that aim to keep them under the consumer’s control.

source https://hackaday.com/2021/01/30/nissan-gives-up-root-shell-thanks-to-hacked-usb-drive/

I was reading Joshua Vasquez’s marvelous piece on the capstan equation this week. It’s a short, practical introduction to a single equation that, unless you’re doing something very strange, covers everything you need to know about friction when designing something with a rope or a cable that has to turn a corner or navigate a wiggle. Think of a bike cable or, in Joshua’s case, a moveable dragon-head Chomper. Turns out, there’s math for that!

Basically, the more you wrap a cable or rope around something stationary, the more friction you have to deal with. I put this to good advantage last Spring when my son and I were doing some random tree-climbing with ropes. Turns out that four or five loops of climbing rope against fairly frictiony bark is enough to hold the weight of a grown man, with nothing other than the weight of the rope itself on the other end, for instance. I was also using this effect in a recent wall-plotter-bot design that uses simple cable braid instead of the ubiquitous timing belt.

In none of these cases did I work out the capstan equation with my pocket calculator: four loops around is almost always enough. But by digging into the math and physics, I got more insight. Basically, the friction is an exponential with the angle times the friction coefficient of your cable in the exponent. So what? So, that next turn holds exponentially more weight when you’re climbing. And the grippiness of the tree bark matters in just the same way. You might know this intuitively from experience, but it’s nice to have numbers.

And what’s even better about the insight from doing the math is what doesn’t matter. The radius of the tree falls out, so you can pick a fat branch or a skinny one, as long as it’ll hold your weight!) The fat branch bends less sharply, which gives you less friction per centimeter, but there’s also more centimeters per wrap, and they cancel out. So pick a fatter, rougher tree over a skinnier, smoother one. I would have never thought that!

Here at Hackaday, we’re big fans of rough-and-ready learning by doing. Will this work? Try it out! (If it shouldn’t, and yet it does, it’s a hack.) But there’s also a lot to be said for knowing the underlying math and physics too. Many people think of math as being about crunching numbers, but I find the deeper intuition about which variables in your problem matter, and which don’t at all, infinitely more useful. Learning by doing, guided by a good physical / mathematical intuition, is the best of both worlds. And it saves wear and tear on your mint HP-48G.

source https://hackaday.com/2021/01/30/run-the-math-or-try-it-out/

If we had to pick one part to crown as the universal component in the world of analogue electronics, it would have to be the operational amplifier. The humble op-amp can be configured into so many circuit building blocks that it has become an indispensable tool for designers. It’s tempting to treat an op-amp as a triangular black box in a circuit diagram, but understanding its operation gives an insight into analogue electronics that’s worth having. [Mitsuru Yamada]’s homemade op-amp using discrete components is thus a project of interest, implementing as it does a complete simple op-amp with five transistors.

Looking at the circuit diagram it follows the classic op-amp with a long-tailed pair of NPN transistors driving a PNP gain stage and finally a complimentary emitter follower as an output buffer. It incorporates the feedback capacitor that would have been an external component on early op-amp chips, and it has a couple of variable resistors to adjust the bias. Keen eyed readers will notice its flaws such as inevitably mismatched transistors and the lack of a current mirror in the long-tailed pair, but using those to find fault in a circuit built for learning is beside the point. He demonstrated it in use, and even goes as far as to show it running an audio power amplifier driving a small speaker.

For the dedicated student of op-amps, may we suggest further reading as we examine the first integrated circuit op-amp?

source https://hackaday.com/2021/01/30/an-op-amp-from-the-ground-up-2/

Hackers love their ThinkPads. They’re easy to work on, well documented, and offer plenty of potential for upgrades. For the more daring, there’s also a wide array of community-developed modifications available. For example, [Berry Berry Sneaky] has recently put together a step-by-step guide on swapping the common ThinkPad rectangular charging port (also used on ThinkBooks and other Lenovo machines) for USB-C Power Delivery.

Now to be clear, this is not a new concept. But between freely sharing the STL for the 3D printed adapter, providing a full parts list, and providing clear instructions on how to put it all together, [Berry Berry Sneaky] has done a fantastic job of making this particular modification as approachable as possible. For the cost of a common PDC004 Power Delivery “trigger” module and a bit of PETG filament, you can add yet another device to the list of things that work with your shiny new USB-C charger.

While not strictly necessary, [Berry Berry Sneaky] recommends getting yourself a replacement DC input cable for your particular machine before you crack open the case. That will let you assemble everything ahead of time, making the installation a lot quicker. It will also let you keep the original rectangular power jack intact so you can swap it back in if something goes wrong or you decide this whole unified charging thing isn’t quite what you hoped for.

Not a member of the ThinkPad Army? No worries. We’ve seen a lot of interest in using these configurable USB-C trigger modules to upgrade all manner of devices to the new Power Delivery standard or sometimes put together custom battery chargers for their older mobile gadgets.

source https://hackaday.com/2021/01/30/usb-c-charging-on-your-thinkpad-one-step-at-a-time/

Abstraction is the core of nearly all progress in computing. Unless you are fabricating your own semiconductors and drawing wire, we all create with building blocks ranging from components like CPUs, to operating system functions, to specialized libraries. Just as you wouldn’t want to spend your time deblocking disk records or rendering fonts for output devices, you probably shouldn’t have to think too much about audio data. While there are some powerful audio processing libraries out there, a new embeddable language called SOUL (SOUnd Language) is now in version 1.0 and wants to help you create efficient code for processing audio.

The goal of SOUL is to target a runtime that can run on CPUs, but is better on DSPs. The code aims to be secure and real time with no pointers, garbage collection, and other things that typically interfere with audio processing or security.

The code isn’t hard to puzzle out. Here’s the example for cutting audio volume by half:

[CODE]

processor MinimalGainExample

{
// declare our inputs and outputs:
input stream float audioIn; // mono input stream called “audioIn”
output stream float audioOut; // mono output stream called “audioOut”

// every processor must declare a run() function
void run()
{
const float gain = 0.5f; // a constant to use as our gain factor

loop // (this just loops forever)
{
audioOut << audioIn * gain; // Read the next input sample, multiply by our // constant, and write it to our output advance(); // Moves all our streams forward by one frame } } } [/CODE] You can see that a processor is essential a thread and can have local and global storage. There are also graphs that assemble different processors with input and output. Usually, when we want to process audio, we turn to PortAudio just like [Matt] did for his oscilloscope port of Quake. We know of some projects that use Pure Data for audio processing, too.

source https://hackaday.com/2021/01/29/soul-wants-to-process-your-audio/