Hackaday Links: June 12, 2016

June 12, 2016 by 36 Comments

The Navy is doing some crazy stuff out in China Lake. They were planning to test something out that could potentially make GPS unusable from San Diego to Las Vegas to San Francisco. Those plans were cancelled for ‘internal’ reasons. They will be testing something in Indiana shortly, though. What are they doing? Who knows. That’s what idle speculation in the comments section is for.

3D Hubs, the distributed ‘3D printing service’ thing, now has 30,000 machines distributed around the globe. They also put together the definitive guide to 3D printing recently. For just about everyone reading this, a ‘introduction to 3D printing’ is old news, but this is a very good guide for telling your weird aunt what you’re building in the basement. Forward this one to your family on Facebook.

This one is amazing. Over on Hackaday.io, [Arsenijs] is working on a Raspberry Pi project. It uses a Raspberry Pi, and several accessories and components to make this Raspberry Pi project work. This Raspberry Pi project is already getting far more than the usual number of likes and follows, making this one of the most interesting Raspberry Pi projects in recent memory.

Moog is re-releasing the Minimoog, the original Moog synth from 1970. That’s cool, but what about a DIY Minimoog? That’s what [Scott Rider] is doing with the Crowminius Analog Music Synthesizer on Kickstarter. It’s an analog synth that’s more or less a Minimoog with MIDI, and one of the Kickstarter rewards is a bare PCB.

The future is dancing robots, so here’s a servo-driven Stewart platform that is sure to bring on the robot apocalypse.

What do you do when you need to get your Hackaday fix, but all you have is a laptop from 1995 and a dial-up modem? The Hackaday Retro Edition, of course. That’s a bunch of retro Hackaday posts, posted five at a time, with all the CSS and JavaScript cruft stripped. We’re always interested to see the old machines that are pulling the retro edition down, and [djnikochan] has the latest entry. He found a Thinkpad 380ED from 1997 at the Goodwill store for $15. The RAM was upgraded with a 64MB SIMM, giving this machine a total of 80MB. The Hackaday Retro Edition is viewable with IE 5.5 over a trusty PCMICA WiFi card. Awesome job, and we love to see old iron rendering the retro edition. Send some pics in if you get your old battlestation to load it.

An Improved WiFi Connected E-Ink Display

June 12, 2016 by 22 Comments

[David] created a great looking e-ink WiFi display project that works a little like a network-connected picture frame with a few improvements over other similar projects. With the help of an ESP8266 it boots up, grabs an 800×600 image over the network, updates the screen, then goes back to sleep. Thanks to some reverse engineering, he was able to make his own firmware for the onboard controller to handle the low-level driving of the display. Since e-ink displays require no power to hold an image and the rest of the unit spends most of the time either asleep or off, power use is extremely low. [David] hopes to go months without needing to recharge the internal lithium-polymer battery.

eink_back
Lithium-polymer charger (top left); Single-cell lithium-polymer battery (center); pullups and power cutoff for nonessential electronics (green board, lower right); ESP866 (lower left).

We previously featured another WiFi-connected e-ink display project that was in fact also the inspiration for this version. [David] uses a 4.3″ 800×600 GDE043A e-ink display and wrote his own firmware for the STM32F103ZE ARM CortexM3 SoC used as a display controller, a process that required some reverse engineering but was aided by the manufacturer providing a closed-source driver for him to use. [David] writes that some reverse-engineering work for this display had already been done, but he had such a hard time getting a clear understanding from it that he reverse engineered the firmware anyway and used the documents mainly for validation and guidance.

As a result, [David] was able to make use of the low-level driver electronics already present on the board instead of having to make and interface his own. E-ink displays have some unusual driving requirements which include generating relatively high positive and negative voltages, and rapidly switching them when updating the display. Taking advantage of the board’s existing low-level driver electronics was a big benefit.

eink_apThe ESP8266 rounds out the project by taking care of periodically booting things up, connecting to the wireless network and downloading an image, feeding the image data to the STM32 to update the display, then disconnecting power from all non-essential electronics and going back to sleep. We especially like how the unit automatically creates a WiFi access point to allow easy (re)configuring.

There’s one more nice touch. [David] goes the extra mile with server software (in the form of PHP scripts) to design screens for the display with data like weather forecasts, stock prices, and exchange rates. Check it out in the project’s github repository.

Quickie USB Keyboard Device

June 12, 2016 by 32 Comments

There are a ton of applications that we use that can benefit from keyboard shortcuts, and we use ’em religiously. Indeed, there are some tasks that we do so often that they warrant their own physical button. And the only thing cooler than custom keyboards are custom keyboards that you’ve made yourself.

Which brings us to [Dan]’s four-button Cherry MX USB keypad. It’s not really all that much more than four keyswitch footprints and an AVR ATmega32u4, but that plus some software is all you really need. He programs the Arduino bootloader into the chip, and then he’s using the Arduino Leonardo keyboard libraries. Bam! Check out the video below.

Continue reading “Quickie USB Keyboard Device” →

Tiny Tiny RGB LED Displays

June 12, 2016 by 17 Comments

Hackaday.io contributor extraordinaire [al1] has been playing around with small LEDs a lot lately, which inevitably leads to playing around with large groups of small LEDs. Matrixes of tiny RGB LEDs, to be precise.

Where's the LED?
Where’s the LED?

First, he took 128 0404 SMD RGB LEDs (yes, 40 thousandths of an inch on each side) and crammed them onto a board that’s just under 37 mm x 24 mm. He calls the project 384:LED (after all, each of those 128 packages has three diodes inside). A microcontroller and the driver chips are located on a separate driver board, which piggy-backs via pin headers to the LED board. Of course, he had to use 0.05 inch headers, because this thing is really small.

Of course, no project is without its hitches. [al1] bought LEDs with the wrong footprint by mistake, so he had a bunch of (subtly different) 0404 LEDs left over. Time for an 8×8 matrix! 192:LED isn’t just the first project cut in half, though. It’s a complete re-design with a four-layer board and the microcontroller on the back-side. And as befits a scrounge project with lots of extreme soldering, he even pulled the microcontroller off of a cheap digital FM radio. Kudos!

We’re in awe of [al1]’s tiny, tiny hacking skills. Now it’s time to get some equally cool graphics up on those little displays.

Retrotechtacular: An Unexpected Meeting With Philo T Farnsworth

June 12, 2016 by 26 Comments

It is not often that you look for one of your heroes on the Internet and by chance encounter another from a completely different field. But if you are a fan of the inimitable silent movie star [Buster Keaton] as well as being the kind of person who reads Hackaday then that could have happened to you just as it did here.

Our subject today is a 1957 episode of CBS’s TV game show I’ve Got a Secret! in which [Keaton] judges a pie-eating contest and is preceded first by a young man with a penchant for snakes and then rather unexpectedly by a true giant of twentieth century technology.

[Philo T Farnsworth] was a prolific engineer who is probably best known as the inventor of electronic television, but whose work touched numerous other fields. Surprisingly this short segment on an entertainment show was his only appearance on the medium to which his invention helped give birth. In it he baffles the panel who fail to guess his claim to fame, before discussing his inventions for a few minutes. He is very effacing about his achievement, making the point that the development of television had been a cumulative effort born of many contributors. He then goes on to discuss the future of television, and talks about 2000-line high-definition TV with a reduced transmission bandwidth, and TV sets like picture frames. All of which look very familiar to us nearly sixty years later in the early 21st century.

The full show is below the break, though [Farnsworth]’s segment is only from 13:24 to 21:24. It’s very much a show of its time with its cigarette product placement and United Airlines boasting about their piston-engined DC-7 fleet, but it’s entertaining enough.

Continue reading “Retrotechtacular: An Unexpected Meeting With Philo T Farnsworth” →

540 LEDs On A Geodesic Sphere

June 12, 2016 by 6 Comments

[burgerga] loves attending Music Festivals. He’s also a MechE who loves his LED’s. He figured he needed to put it all together and do something insane, so he build a huge, 15″ geodesic sphere containing 540 WS2812B addressable LED’s. He calls it the SOL CRUSHER. It sips 150W when all LED’s are at full intensity, making it very, very, bright.

As with most WS2812B based projects, this one too is fairly straightforward, electrically. It’s controlled by four Teensy 3.2 boards mounted on Octo WS2811 adapter boards. Four 10,000 mAh 22.2V LiPo batteries provide power, which is routed through a 5V, 30Amp heatsinked DC-DC converter. To protect his LiPo batteries from over discharge, he built four voltage monitoring modules. Each had a TC54 voltage detector and an N-channel MOSFET which switches off the LiPo before its voltage dips below 3V. He bundled in a fuse and an indicator, and put each one in a neat 3D printed enclosure.

The mechanical design is pretty polished. Each of the 180 basic modules is a triangular PCB with three WS2812B’s, filter capacitors, and heavy copper pours for power connections. The PCB’s are assembled in panels of six and five units each, which are then put together in two hemispheres to form the whole sphere. His first round of six prototypes set him back as he made a mistake in the LED footprint. But it still let him check out the assembly and power connections. For mechanical support, he designed an internal skeleton that could be 3D printed. There’s a mounting frame for each of the PCB panels and a two piece central sphere. Fibreglass rods connect the central sphere to each of the PCB panels. This lets the whole assembly be split in to two halves easily.

It took him over six months and lots of cash to complete the project. But the assembly is all done now and electrically tested. Next up, he’s working on software to add animations. He’s received suggestions to add sensors such as microphones and accelerometers via comments on Reddit. If you’d like to help him by contributing animation suggestions, he’s setup a Readme document on Dropbox, and a Submission form. Checkout the SolCrusher website for more information.

Thanks [Vinny Cordeiro], for letting us know about this build.

Continue reading “540 LEDs On A Geodesic Sphere” →

Using WS2811 Chip To Drive Incandescent Lamps

June 12, 2016 by 6 Comments

What makes the WS2812-style individually addressable pixel LEDs so inviting? Their rich colors? Nope, you can get RGB LEDs anywhere. Their form factor? Nope. Even surface-mount RGBs are plentiful and cheap. The answer: it’s the integrated controller. It’s just so handy to speak an SPI-like protocol to your LEDs — it separates the power supply from the data, and you can chain them to your heart’s desire. Combine this controller and the LEDs together in a single package and you’ve got a runaway product success.

But before the WS2812, there was the WS2811 — a standalone RGB controller IC. With the WS2812s on the market, nobody wants the lowly WS2811’s anymore. Nobody except [Michael Krumpus], that is. You see, he likes the old-school glow of incandescent, but likes the way the WS2812 strings are easy to drive and extend. So he bought a bag of WS2811s and put the two together.

The controller IC can’t handle the current that an incandescent bulb requires, so he added a MOSFET to do the heavy lifting. After linking a few of these units together, he discovered (as one does with the LED-based WS2812s eventually) that the switching transients can pull down the power lines, so there is a beefy capacitor accompanying each bulb.

He wanted each bulb to be independently addressable, so he only used the blue line of the RGB controller, which leaves two outputs empty. I’m sure you can figure out something to do with them.

Needless to say, we’ve seen a lot of WS2812 hacks here. It’s hard to pick a favorite. [Mike] of “mike’s electric stuff” fame built what may be the largest installation we’ve seen, and this hack that effectively projection-maps onto a randomly placed string of WS2812s is pretty cool. But honestly, no project that blinks or glows can go far wrong, right?

Continue reading “Using WS2811 Chip To Drive Incandescent Lamps” →