Hackaday Prize Entry: MOLBED Braille Display

Electromechanical braille displays, where little pins pop up or drop down to represent various characters, can cost upwards of a thousand dollars. That’s where the Modular Low-cost Braille Electro Display, aka MOLBED, steps up. The project’s creator, [Madaeon] aims to create a DIY-friendly, 3D-printable,  and simple braille system. He’s working on a single character’s display, with the idea it could be expanded to cover a whole row or even offer multiple rows.

[Madeon]’s design involves using Flexinol actuator wire to control whether a pin sticks or not. He designed a “rocker” system consisting of a series of 6 pins that form the Braille display. Each pin is actuated by two Flexinol wires, one with current applied to it and one without, popping the pin up about a millimeter. Swap polarity and the pin pops down to be flush with the surface.

This project is actually [Madeon]’s second revision of the MOLBED system. The first version, an entry to the Hackaday Prize last year, used very small solenoids with two very small magnets at either end of the pole to hold the pin in place. The new system, while slightly more complex mechanically, should be easier to produce in a low-cost version, and has a much higher chance of bringing this technology to people who need it. It’s a great project, and a great entry to the Hackaday Prize.

Hackaday Prize Entry: The $50 Raspberry Pi Smartphone

The Hackaday Prize is a challenge to create hardware, and the ZeroPhone is quite possibly the most popular project entered in the Hackaday Prize. What is it? It’s a mobile phone built around the Raspberry Pi Zero that can be assembled for about $50 in parts. Already, it’s a finalist in the Hackaday Prize best product competition, a finalist for the grand prize of $50,000, and one of the most popular projects on Hackaday.io of all time.

We took a look at the ZeroPhone early this year, and while there have been significant advances in this project, the philosophy is still pretty much the same. This is a mobile phone with a numeric keypad and a 128 x 64 pixel OLED display — basically the same user interface as a Nokia brick. The brain of the phone is a Raspberry Pi Zero wrapped in a PCB sandwich, with options for WiFi, Bluetooth, HDMI and audio outputs, a USB port, battery charging, and a ton of GPIOs that include ISM band radios, infrared receivers and transmitters, more flash storage, and anything else you can imagine. Basically, we’re looking at one of those modular, reconfigurable smartphone ideas, using a Raspberry Pi as the brains. Tech journos should be creaming themselves over this. We’re looking forward to [Arsenijs]’ cover story in Wired.

As with any Open Source / DIY cell phone, the big question surrounding the ZeroPhone is the cellular radio. 2G radios are cheap and plentiful, but the infrastructure is either coming down shortly, or already is down. A 3G radio is a must for a minimum viable product, and [Arsenijs] says there are provisions for replacing the 2G radio with a 3G module. Of course, 3G modules aren’t as capital-‘O’-Open as their technological predecessors, but that’s a discussion for another time.

Already the ZeroPhone is a huge success. There’s an actual team working on this project, the ZeroPhone subreddit is bigger than the Hackaday subreddit, there are newsletters, a wiki, and there will be a crowdfunding campaign ‘shortly’. This is one to look out for, and a very worthy project in the running for the 2017 Hackaday Prize.

Hackaday Prize Entry: A PCB To Emulate Coin Cells

The Coin Cell Emulator CR2016/CR2032 by [bobricius] homes in on a problem some hardware developers don’t realize they have: when working on hardware powered by the near-ubiquitous CR2016 or CR2032 format 3V coin cells, power can be a bit troublesome. Either the device is kept fed with coin cells as needed during development, or the developer installs some breakout wires to provide power from a more convenient source.

[bobricius]’s solution to all this is a small PCB designed to be inserted into most coin cell holders just like the cell itself. It integrates a micro USB connector with a 3V regulator for using USB as an external power source. The board also provides points for attaching alligator clips, should one wish to conveniently measure current consumption. It’s a tool with a purpose, and cleverly uses the physical shape of the PCB itself as an integral part of the function, much like another of [bobricius]’s projects: the Charlieplexed 7-segment LED display.

Hackaday Prize Entry: You Can Tune A Guitar, But Can You Reference REO Speedwagon?

Just for a second, let’s perform a little engineering-based thought experiment. Let’s design a guitar tuner. First up, you’ll need a 1/4″ input, and some op-amps to get that signal into a microcontroller. In the microcontroller, you’re going to be doing some FFT. If you’re really fancy, you’ll have some lookup tables and an interface to switch between A440, maybe A430, and if you’re a huge nerd, C256. The interface is simple enough — just use a seven-segment display and a few LEDs to tell the user what note they’re on and how on-pitch they are. All in all, the design isn’t that hard.

Now let’s design a tuner for blind musicians. This makes things a bit more interesting. That LED interface isn’t going to work, and you’ve got to figure out a better way of telling the musician they’re on-pitch. This is the idea of [Pepijn]’s Accessible Guitar Tuner. It’s a finalist in The Hackaday Prize Assistive Technology round, and a really interesting problem to solve.

Most of [Pepijn]’s tuner is what you would expect — microcontrollers and FFT. The microcontroller is an ATMega, which is sufficient enough for a simple guitar tuner. The real trick here is the interface. [Pepijn] modulating the input from the guitar against a reference frequency. The difference between the guitar and this reference frequency is then turned into clicks and played through headphones. Fewer clicks mean the guitar is closer to being in tune.

This is one of those projects that’s a perfect fit for the Hackaday Prize Assistive Technology round. It’s an extremely simple problem to define, somewhat easy to build, and very useful. That doesn’t mean [Pepijn] isn’t having problems — he’s having a lot of trouble with the signal levels from a guitar. He’s looking for some help, so if you have some insights in reading signals that range from tiny piezos to active humbuckers, give him a few words of advice.

Hackaday Prize Entry: SoleSense For Balance Therapy

Rehabilitating brain injuries where a patient’s sense of balance has been compromised is no easy task. Current solutions only trigger when the patient reaches a threshold and by then, it may already be too late for a graceful recovery. [Simon Merrett]’s SoleSense is being designed to give continuous feedback like a stock humans innate sense of balance. Therapists hope this will aid recovery by more closely imitating what most of us grew up with.

SoleSense relies on capacitive sensors arranged under the feet to know where the patients are placing their weight. [OSHPark] is providing the first round of flexible PCBs so some lucky sole is going to get purple inserts.

Outside of recovery, devices like this can teach better posture or possibly enhance a fully functioning sense of balance. That could improve physical performance. Who knows, we are finding new ways of perceiving the world all the time.

Remapping senses is a popular assistive technology and sound is ideal for the SoleSense to piggyback because brain injuries are less likely to affect hearing than other senses. Of course, senses can be remapped or even created. You could gain a sense of magnetic north or expand the range of light you can perceive.

Hackaday Prize Entry: An Optical Power Meter

This is the type of crowd that’s famous for building their own test equipment. If you need a way to program a flash chip, don’t go out and buy one — you can just build one. Need a spectrum analyzer? You can build that out of copper clad board. For his Hackaday Prize entry, [oakkar7] is building an optical power meter, capable enough to do futzy fiber work, but still completely DIY.

When you get into networking and telecom connections that don’t begin with the letters ‘RJ’, you start to stumble upon SPF transceivers. These ‘small form factor pluggable’ devices are little modular transceivers capable of handling fiber, Gigabit Ethernet, and other slightly weirder bit pipes. When used with fiber, they can measure optical power in dBm and watts, and can be debugged by a UART.

[oakkar]’s optical power meter uses these SPF transceivers, tied together with a fairly simple circuit consisting of an Arduino, a few tact switches, a Nokia LCD, and an FTDI UART. The key in tying all of this together is an Arduino library for SPF and DDM (Digital Diagnostics Monitoring), giving the user access to all the configuration bits in these transceivers.

While the circuit is simple enough to be built on a piece of perfboard, [oakkar] really knocked it out of the park with the enclosure on this one. With just a little bit of laser cut acrylic and a few standoffs, [oakkar] has a device that actually looks professional, and has most of the capabilities of fancier, more expensive tools.

Hackaday Prize Entry: Room-Tracking Red Vines Flinger

[Vije Miller]’s Arduino Licorice Launcher is based on the simple and logical premise that one must always have a voice-activated Red Vines catapult in the workshop. When he calls out to the robot, it turns to aim at him and flings a piece of licorice at his head.

The chassis is CNCed out of quarter-inch MDF and the spring-loaded catapult arm is managed by two servos, one to tension the arm and one to secure it until it’s triggered.  Third and fourth servos aim the catapult and dispense another piece of licorice from the magazine. His robot adapts a radio homing technique [Vije] learned about from RoboWarner, which allows a robot to track a moving RF signal.

[Vije]’s first prototype uses an Arduino Uno connected to a serial port on a PC, but he hopes to acquire an MKR1000 WiFi module, which combines a Arduino Zero with WiFi. Already, this Red Vines launcher is a complete success; the marketing team at Red Vines sent him a huge pile of swag and free licorice for his efforts. You can check out [Vije]’s promo video of the project below.

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