Is That A Word Clock In Your Pocket?

February 15, 2019 by Tom Nardi 10 Comments

Word clocks are one of those projects that everyone seems to love. Even if you aren’t into the tech behind how they work, they have a certain appealing aesthetic. Plus you can read the time without worrying about those pesky numbers, to say nothing of those weird little hands that spin around in a circle. This is the 21st century, who has time for that?

Now, thanks to [Gordon Williams], these decidedly modern timepieces just got a lot more accessible. His word clock is not only small enough to fit in the palm of your hand, but it’s the easiest-to-build one we’ve ever seen. If you were ever curious about these gadgets but didn’t want to put in the the time and effort required to build a full scale version, this diminutive take on the idea might be just what Father Time ordered.

The trick is to attach the microcontroller directly to the backside of an 8 x 8 LED matrix. As demonstrated by [Gordon], the Bluetooth-enabled Espruino MDBT42Q fits neatly between the rows of pins, which need only a gentlest of persuasions to get lined up and soldered into place. Since the time can be set remotely over Bluetooth, there’s not even so much as an additional button required. While driving the LEDs directly off of the digital pins of a microcontroller is never recommended, the specifics of this application (only a few of the LEDs on at a time, and not for very long) means he can get away with it.

Of course, that just gets you an array of square LEDs you blink. It wouldn’t be much of a word clock without, you know, words. To that end, [Gordon] has provided an overlay which you can print on a standard inkjet printer. While it’s not a perfect effect as the light still comes through the ink, it works well enough to get the point across. One could even argue that the white letters on the gray background helps with visibility compared to just the letters alone lighting up.

If you’re not in the market for a dollhouse-sized word clock, fear not. We’ve got no shortage of adult sized versions of these popular timepieces for your viewing pleasure.

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Building A Semiautomatic Swag Launcher

February 15, 2019 by Tom Nardi 4 Comments

Regular readers of Hackaday have certainly seen the work of [Jeremy Cook] at this point. Whether you remember him from his time as a writer for this fine online publication, or recognize the name from one of his impressive builds over the last few years, he’s a bona fide celebrity around these parts. In fact, he’s so mobbed with fans at events that he’s been forced to employ a robotic companion to handle distributing his personalized buttons for his own safety.

Alright, that might be something of a stretch. But [Jeremy] figured it couldn’t hurt to have an interesting piece of hardware handing out his swag at the recent Palm Bay Mini Maker Faire. Anyone can just put some stickers and buttons in a bowl on a table, but that’s hardly the hacker way. In the video after the break, he walks viewers through the design and construction of this fun gadget, which takes a couple unexpected turns and has contains more than a few useful tips which are worth the cost of admission alone.

Outwardly the 3D printed design is simple enough, and reminds us of those track kits for Matchbox cars. As you might expect, getting the buttons to slide down a printed track was easy enough. Especially when [Jeremy] filed the inside smooth to really get them moving. But the goal was to have a single button get dispensed each time the device was triggered, but that ended up being easier said than done.

The first attempt used magnets actuated by two servos, one to drop the button and the other to hold up the ones queued above it. This worked fine…at first. But [Jeremy] eventually found that as he stacked more buttons up in the track, the magnets weren’t strong enough to hold them back and they started “leaking”. This is an excellent example of how a system can work perfectly during initial testing, but break down once it hits the real world.

In this case, the solution ended up being relatively simple. [Jeremy] kept the two servos controlled by an Arduino and a capacitive sensor, but replaced the magnets with physical levers. The principle is the same, but now the system is strong enough to hold back the combined weight of the buttons in the chute. It did require him to cut into the track after it had already been assembled, but we can’t blame him for not wanting to start over.

Just like the arcade inspired candy dispenser, coming up with a unique way of handing out objects to passerby is an excellent way to turn the ordinary into a memorable event. Maybe for the next iteration he can make it so getting a button requires you to pass a hacker trivia test. Really make them work for it.

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Juicing Up The Chevy Volt With Raspberry Pi

February 15, 2019 by Tom Nardi 31 Comments

While Chevrolet’s innovative electric hybrid might officially be headed to that great big junkyard in the sky, the Volt will still live on in the hearts and minds of hackers who’d rather compare amp hour than horsepower. For a relatively low cost, a used Volt offers the automotive hacker a fascinating platform for upgrades and experimentation. One such Volt owner is [Katie Stafford], who’s recently made some considerable headway on hacking her hybrid ride.

In an ongoing series on her blog, [Katie] is documenting her efforts to add new features and functions to her Volt. While she loves the car itself, her main complaint (though this is certainly not limited to the Volt) was the lack of tactile controls. Too many functions had to be done through the touch screen for her tastes, and she yearned for the days when you could actually turn a knob to control the air conditioning. So her first goal was to outfit her thoroughly modern car with a decidedly old school user interface.

Like most new cars, whether they run on lithium or liquefied dinosaurs, the Volt makes extensive use of CAN bus to do…well, pretty much everything. Back in the day it only took a pair of wire cutters and a handful of butt splice connectors to jack into a car’s accessory systems, but today it’s done in software by sniffing the CAN system and injecting your own data. Depending on whether you’re a grease or a code monkey, this is either a nightmare or a dream come true.

Luckily [Katie] is more of the latter, so with the help of her Macchina M2, she was able to watch the data on the CAN bus as she fiddled with the car’s environmental controls. Once she knew what data needed to be on the line to do things like turn on the fan or set the desired cabin temperature, she just needed a way to trigger it on her terms. To that end, she wired a couple of buttons and a rotary encoder to the GPIO pins of a Raspberry Pi, and wrote some code that associates the physical controls with their digital counterparts.

That’s all well and good when you need to mess around with the AC, but what’s the Pi supposed to do the rest of the time? [Katie] decided a small HDMI display mounted to the dash would be a perfect way for the Raspberry Pi to do double duty as information system showing everything from battery charge to coolant temperature. It also offers up a rudimentary menu system for vehicle modifications, and includes functions which she wanted quick access to but didn’t think were necessarily worth their own physical button.

In the video after the break, [Katie] walks the viewer through these modifications, as well as some of the other neat new features of her battery powered bow tie. What she’s already managed to accomplish without having to do much more than plug some electronics into the OBD-II port is very impressive, and we can’t wait to see where it goes from here.

Today there are simply too many good electric cars for hybrids like the Chevy Volt and its swankier cousin the Cadillac ELR to remain competitive. But thanks to hackers like [Katie], we’re confident this isn’t the last we’ve seen of this important milestone in automotive history.

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Be Ready To Roll With Universal Electronic Dice

February 14, 2019 by Tom Nardi 4 Comments

There are applications you can download for your smartphone that can “roll” an arbitrary number of dice with whatever number of sides you could possibly want. It’s faster and easier than throwing physical dice around, and you don’t have to worry about any of them rolling under the couch. No matter how you look at it, it’s really a task better performed by software than hardware. All that being said, there’s something undeniably appealing about the physical aspect of die rolling when playing a game.

Luckily, [Paul Klinger] thinks he has the solution to the problem. His design combines the flexibility of software number generation with the small form factor of a physical die. The end result is a tiny gadget that can emulate anything from a 2 to 64 sided die with just 6 LEDs while remaining as easy to operate as possible. No need to tap on your smartphone screen with Cheetos-stained hands when you’ve got to make an intelligence check, just squeeze the Universal Electronic Die and off you go. Granted you’ll need to do some binary math in your head, but if you’re the kind of person playing D&D with DIY electronic dice, we think you’ll probably be able to manage.

The 3D printed case that [Paul] came up with for his digital die is very clever, though it did take him awhile to nail it down. As shown in the video after the break, it took seven iterations before he got the various features such as the integrated button “flaps” right. There’s also a printed knob to go on the central potentiometer, to make it easier to select how many sides your virtual die will have.

In terms of the electronics, the design is actually quite simple. All that lives on the custom PCB is a ATtiny1614 microcontroller, the aforementioned LEDs, and a couple of passive components. A CR2032 coin cell powers the whole operation, and it should provide enough juice for plenty of games as it’s only turned on when the user is actively “rolling”.

We’ve seen a number of very impressive electronic dice projects over the years, and it doesn’t look like the trend is slowing down anytime soon. Of course, if you absolutely must hear those physical dice rolling, we can help you with that too.

The Empire Strikes Back With The ESP8266

February 13, 2019 by Tom Nardi 1 Comment

Like many of us, [Matthew Wentworth] is always looking for a reason to build something. So when he found a 3D model of the “DF.9” laser turret from The Empire Strikes Back intended for Star Wars board games on Thingiverse, he decided it was a perfect ~~excuse~~ opportunity to not only try his hand at remixing an existing 3D design, but adding electronics to it to create something interactive.

As the model was originally intended for a board game, it was obviously quite small. So the first order of business was scaling everything up to twice the original dimensions. As [Matthew] notes, the fact that it still looks so good when expanded by such a large degree is a credit to how detailed the original model is. Once blown up to more useful proportions, he modified the head of the turret as well as the barrel to accept the electronics he planned on grafting into the model.

He created a mount for a standard nine gram servo inside the head of the turret which allows it to rotate, and the barrel got an LED stuck in the end. Both of which are controlled with a NodeMCU ESP8266 development board, allowing [Matthew] to control the direction and intensity of the pew-pew over WiFi. He mentions that in the future he would like to add sound effects that are synchronized to the turret rotation and LED blinking.

For the software side of the project, he used Blynk to quickly build a smartphone interface for the turret. This is the first time he had used Blynk, and reports that outside of a little trial and error, it was some of the easiest code he’s ever written for the Arduino. This is a sentiment we’ve been seeing a lot of recently towards Blynk, and it’s interesting to see how often it shows up in ESP8266 projects now.

Looking ahead [Matthew] says he wants to paint and detail the turret, as the bright orange color scheme probably wouldn’t do terribly well on Hoth. If he can manage the time, he’d also like to add it to the long list of OpenCV-powered turrets that hackers love harassing their friends and family with.

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The “Impossible” Tech Behind SpaceX’s New Engine

February 13, 2019 by Tom Nardi 92 Comments

Followers of the Church of Elon will no doubt already be aware of SpaceX’s latest technical triumph: the test firing of the first full-scale Raptor engine. Of course, it was hardly a secret. As he often does, Elon has been “leaking” behind the scenes information, pictures, and even video of the event on his Twitter account. Combined with the relative transparency of SpaceX to begin with, this gives us an exceptionally clear look at how literal rocket science is performed at the Hawthorne, California based company.

This openness has been a key part of SpaceX’s popularity on the Internet (that, and the big rockets), but its been especially illuminating in regards to the Raptor. The technology behind this next generation engine, known as “full-flow staged combustion” has for decades been considered all but impossible by the traditional aerospace players. Despite extensive research into the technology by the Soviet Union and the United States, no engine utilizing this complex combustion system has even been flown. Yet, just six years after Elon announced SpaceX was designing the Raptor, they’ve completed their first flight-ready engine.

The full-flow staged combustion engine is often considered the “Holy Grail” of rocketry, as it promises to extract the most possible energy from its liquid propellants. In a field where every ounce is important, being able to squeeze even a few percent more thrust out of the vehicle is worth fighting for. Especially if, like SpaceX, you’re planning on putting these new full-flow engines into the world’s largest operational booster rocket and spacecraft.

But what makes full-flow staged combustion more efficient, and why has it been so difficult to build an engine that utilizes it? To understand that, we’ll need to first take a closer look at more traditional rocket engines, and the design paradigms which have defined them since the very beginning.

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A Network Attached Radiation Monitor

February 13, 2019 by Tom Nardi 25 Comments

It started as a joke, as sometimes these things do. [Marek Więcek] thought building a personal radiation detector would not only give him something to work on, but it would be like having a gadget out of the Fallout games. He would check the data from time to time and have a bit of a laugh. But then things got real. When he started seeing rumors on social media that a nearby nuclear reactor had suffered some kind of radiation leak, his “joke” radiation detector suddenly became serious business.

With the realization that having his own source of detailed environmental data might not be such a bad idea after all, [Marek] has developed a more refined version of his original detector (Google Translate). This small device includes a Geiger counter as well as sensors for more mundane data points such as temperature and barometric pressure. Since it’s intended to be a stationary monitoring device, he even designed it to be directly plugged into an Ethernet network so that it can be polled over TCP/IP.

[Marek] based the design around a Soviet-era STS-5 Geiger tube, and outfitted his board with the high voltage electronics to provide it with the required 400 volts. Temperature, barometric pressure, and humidity are read with the popular Bosch BME280 sensor. If there’s no Ethernet network available, data from the sensors can be stored on either the built-in SPI flash chip or a standard USB flash drive.

The monitor is powered by a PIC32MX270F256B microcontroller with an Ethernet interface provided by the ENC28J60 chip. In practice, [Marek] has a central Raspberry Pi that’s polling the monitors over the network and collecting their data and putting it into a web-based dashboard. He’s happy with this setup, but mentions he has plans to add an LCD display to the board so the values can be read directly off of the device. He also says that a future version might add WiFi for easier deployment in remote areas.

Over the years we’ve seen a fair number of radiation monitors, from solar-powered WiFi-connected units to the incredible work [Radu Motisan] has done building his global network of radiation detectors. It seems hackers would rather not take somebody else’s word for it when it comes to the dangers of radiation.