Hackaday Links: May 24, 2015

A few months ago, we heard about a random guy finding injection molds for old Commodore computers. He did what the best of us would do and started a Kickstarter to remanufacture these cool old cases. It’s the best story on retrocomputing this year, and someone else figured out they could remanufacture Commodore 64 keycaps. If you got one of these remanufactured cases, give the keycaps a look.

Remember this Android app that will tell you the value of resistors by reading their color code. Another option for the iOS crowd was presented at Maker Faire last weekend. It’s called ResistorVision, and it’s perfect for the colorblind people out there. An Android version of ResistorVision will be released sometime in the near future.

A few folks at Langly Research Center have a very cool job. They built a hybrid electric tilt wing plane with eight motors on the wing and two on the tail. It’s ultimately powered by two 8 hp diesel engines that charge Liion batteries. When it comes to hydrocarbon-powered hovering behemoths, our heart is with Goliath.

A bottom-of-the-line avionics panel for a small private plane costs about $10,000. How do you reduce the cost? Getting rid of FAA certification? Yeah. And by putting a Raspberry Pi in it. It was expoed last month at the Sun ‘N Fun in Florida, and it’s exactly what the pilots out there would expect: a flight system running on a Raspberry Pi. It was installed in a Zenith 750, a 2-seat LSA, registered as an experimental. You can put just about anything in the cabin of one of these, and the FAA is okay with it. If it’ll ever be certified is anyone’s guess.

LayerOne Hardware Hacking Village

Go to DEFCON and you’ll stand in line for five hours to get a fancy electronic badge you’ll be showing to your grandchildren some day. Yes, at DEFCON, you buy your hacker cred. LayerOne is not so kind to the technically inept. At LayerOne, you are given a PCB, bag of parts, and are told to earn your hacker cred by soldering tiny QFP and SOT-23 chips by hand. The Hardware Hacking Village at LayerOne was packed with people eagerly assembling their badge, or badges depending on how cool they are.

The badges are designed by [charlie x] of null space labs, one of the many local hackerspaces around the area. The design and construction of these badges were documented on the LayerOne Badge project on hackaday.io, and they’re probably best con badges we’ve ever seen.

There are two badges being distributed around LayerOne. The first is an extremely blinkey badge with a Cypress PSoC4 controlling 22 individually addressable RGB LEDs. Most conference attendees received a bare PCB and a bag of parts – the PCB will get you in the door, but if you want your nerd cred, you’ll have to assemble your own badge.

There are still a few interesting features for this badge, including an ESP8266 module that will listen to UDP packets and drive the LEDs. Yes, a random person on the same WiFi AP can control the LEDs of the entire conference event. The badges can also be chained together with just three wires, but so far no one has done this.

The Speaker and Staff badge, based on a VoCore

The second badge – for speakers and staff – is exceptionally more powerful. It’s a Linux box on a badge with two Ethernet connectors running OpenWRT. For a con badge, it’s incredibly powerful, but this isn’t the most computationally complex badge that has ever been at a LayerOne conference. For last year’s badge, [charlie] put together a badge with an FPGA, SAM7 microcontroller, SD card, and OLED display. They were mining Bitcons on these badges.

The Hardware Hacking Village was loaded up with a dozen or so Metcal soldering irons, binocular microscopes, and enough solder, wick, and flux to allow everyone to solder their badge together. Everyone who attempted it actually completed their badge, and stories of badge hacking competitions at other cons were filled with tales of people sprinkling components on random solder pads. Imagine: a conference where people are technically adept. Amazing.

Hackaday Prize Entry: Arduino MPPT Controller

Imagine you’re building a small solar installation. The naive solution would be grabbing a solar panel from Horror Freight, getting a car battery and AC inverter, and hoping everything works. This is the dumb solution. To get the most out of a solar you need to match the voltage of the solar cell to the voltage of the battery. How do you do that? With [Debasish]’s entry for The Hackaday Prize, an Arduino MPPT Solar Charge Controller.

This Maximum Power Point Tracker uses a buck converter to step down the voltage from the solar cell to the voltage of the battery. It’s extremely efficient and every proper solar installation will need a charge controller that does something similar.

For his MPPT, [Debasish] is using an Arduino Nano for all the math, a DC to DC buck converter, and a few MOSFETs. Extremely simple, but [Debasish] is connecting the entire controller to the Internet with an ESP8266 module. It’s a great example of building something for much less than it would cost to buy the same thing, and a great example for something that has a chance at making the world a little better.


The 2015 Hackaday Prize is sponsored by:

Finally, VR For Four Eyes

In the next few years, VR headsets will be everywhere, and everyone will slowly recede into their own little reality that is presented on high-resolution displays right in front of their eyes. One specific group will be left out: eyeglass wearers. VR just doesn’t work with eyeglasses, and a few people in Germany are fixing this problem. They’re creating custom prescription lenses for Google Cardboard, giving anyone with glasses the opportunity to look just a little more hipster.

The folks behind this Indiegogo already run a specialty optics shop in Germany. They have the tools to make custom lenses for spectacles, and they’re the first company so far that has identified a problem with the current crop of VR headsets and has created a solution. The campaign is for a set of lenses that can be attached to Google Cardboard with double stick tape. There are limitations on how strong of a prescription they can make, but it should work for most four eyes.

It should be noted this Indiegogo isn’t the only way to get custom lenses for a VR headset. If you have your prescription, there are a few places to buy glasses online for $30 or so. Do that, remove the lenses from the frame, and affix them to Cardboard.

Hackaday Fail: A $3000 Prototype That Doesn’t Work

[Dan Royer] is hard at work building his own personal robot army. Robots mean motors, and motors mean gearboxes. In [Dan]’s case, gearboxes mean $3000 wasted on a prototype that doesn’t work. Why doesn’t it work? He doesn’t know, and we don’t either.

[Dan] would like to use small but fast DC motors for his robots coupled to a gearbox to step down the speed and increase the torque. The most common way of doing this is with a planetary gear set, but there’s a problem with the design of planetary gears – there is inherent backlash and play between the gears. This makes programming challenging, and the robot imprecise.

A much better way to gear down a small DC motor is a hypocycloid gear. If you’ve ever seen the inside of a Wankel engine, this sort of gearing will look very familiar: a single gear is placed slightly off-axis inside a ring gear. On paper, it works. In reality, not so much.

[Dan] spent $3000 on a prototype hypocycloid gearbox that doesn’t turn without binding or jamming. The gear was made with incredible tolerances and top quality machining, but [Dan] has a very expensive paper weight sitting on his desk right now.

If anyone out there has ever designed or machined a hypocycloid gearbox that works, your input is needed. The brightest minds [Dan] met at the Bring A Hack event at Maker Faire last weekend could only come up with. ‘add more lasers’, but we know there’s a genius machinist out there that knows exactly how to make this work.

2013-09-05-Hackaday-Fail-tips-tileHackaday Fail is a column which runs every now and again. Help keep the fun rolling by writing about your past failures and sending us a link to the story — or sending in links to fail write ups you find in your Internet travels.

Hackaday Prize Entry: Biopotential Signal Library

With prosthetics, EEG, and all the other builds focused on the body and medicine for this year’s Hackaday Prize, it might be a good idea to take a look at what it takes to measure the tiny electrical signals that come from the human body. Measuring brain waves or heartbeats indoors is hard; AC power frequencies easily couple to the high impedance inputs for these measurements, and the signals themselves are very, very weak. For his entry to The Hackaday Prize, [Paul Stoffregen] is building the tools to make EEG, ECG, and EMG measurements easy with cheap tools.

If the name [Stoffregen] sounds familiar, it’s because he’s the guy behind the Teensy family of microcontroller boards and several dozen extremely popular libraries for everything from displays to real time clocks. The biopotential signal library continues in [Paul]’s tradition of building very cool stuff with just code.

The hardware used in this project is TI’s ADS1294, a 24-bit ADC with either 4 or 8 channels. This chip is marketed as a medical analog front end with a little bit of ECG thrown in for good measure. [Paul] is only using the ADS1294 initially; more analog chips can be added later. It’s a great project in its own right, and when you include the potential applications of this library – everything from prosthetics to body sensors – it makes for an awesome Hackaday Prize entry.

The 2015 Hackaday Prize is sponsored by:

Tessel 2, A $35 Linux Computer That’s Truly Open Source

We’ve seen the first version of the Tessel a few years ago, and it’s still an interesting board: an ARM Cortex-M3 running at 180MHz, WiFi, 32 Megs of both Flash and RAM, and something that can be programmed entirely in JavaScript or Node.js. Since then, the company behind Tessel, Technical Machines, has started work on the Tessel 2, a board that’s continuing in the long tradition of taking chips from WiFi routers and making a dev board out of them. The Tessel 2 features a MediaTek MT7620 running Linux built on OpenWRT, Ethernet, 802.11bgn WiFi, an Atmel SAMD21 serving as a real-time I/O coprocessor, two USB ports, and everything can still be controlled through JavaScript, Node, with support for Rust and other languages in the works.

Instead of going the usual route and determining the future of Tessel through market research and the apparent pragmatism of whoever happens to be in charge, this week Technical Machines did something wonderful: the ownership and direction of the Tessel Project is now independent of Technical Machine. This makes Tessel a completely open source and community driven platform for I0T, robots, and whatever else would benefit from an open source community disconnected from hardware.

The Tessel project is completely disconnected from manufacturers, something the Arduino project has been struggling with for the last few years, unbeknownst to most of the founders for most of that time. It’s a boon for the open source community, and something that should see an incredible uptake in the next few months.