Building A Blink Based Input Device

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Fans of the AMC show Breaking Bad will remember the Original Gangsta [Hector Salamanca]. When first introduced to the story he communicates by ringing a bell. But after being moved to a nursing home he communicates by spelling out messages with the assistance of a nurse who holds up a card with columns and rows of letters. This hack automates that task, trading the human assistant for a blink-based input system.

[Bob Stone] calls the project BlinkTalk. The user wears a Neurosky Mindwave Mobile headset. This measures brainwaves using EEG. He connects the headset to an mBed microcontroller using a BlueSMiRF Bluetooth board. The microcontroller processes the EEG data to establish when the user blinks their eyes.

The LCD screen first scrolls down each row of the displayed letters and numbers. When the appropriate row is highlighted a blink will start scrolling through the columns until a second blink selects the appropriate character. Once the message has been spelled out the “SAY!” menu item causes the Emic2 module to turn the text into speech.

If you think you could build something like this to help the disabled, you should check out thecontrollerproject.com where builders are connected with people in need.

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Ditch That Boring Mouse For A Military-grade Trackball

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The bad thing about this type of hack is that now [Tomek Dubrownik] needs to cut a hole in his desk to house the thing. He got this military grade trackball working over USB. It’s old, and could be used as a blunt weapon. But as the video shows it still makes a great input device.

He found the hardware on Allegro — a Polish auction site similar to eBay — for just $20. The original circuitry didn’t make a lot of sense, but a bit of probing with the old oscilloscope let him establish connections to the encoders which are read by some TI 54xx parts. Apparently they use the same logic as 7400 parts but are military grade. He chose a ATmega32u4 development board for his replacement control board. That chip has native USB support so the rest is just a matter of passing data like an HID input device. His code even lets him use those pushbuttons to toggle between cursor movement and window scrolling.

[Tomek] translated his post into English after some prompting by friends at the Warsaw Hackerspace. Here’s the original in Polish if you’re interested.

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Gesture Control Uses WiFi Doppler Shift

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We’ve said it before: in the future simple interfaces will use nothing but your body. At least at first glance that’s the case with this WiFi-based gesture control system. If you have Internet at home you probably have a WiFi access point. That’s the first portion of the equation. The remainder is a way of measuring how the radio waves bounce off of your body. So far this is being done with Software-Define Radio (SDR) but researchers at University of Washington think it may be possible to build the technique into future WiFi devices.

The demo video shows this man waving his arm to adjust the volume of his home entertainment system. Intuition tells us that this would be impossible if your arm wasn’t the only thing in motion at the time. But that issue is quickly addressed. Multiple antennas can track multiple people at the same time. There is also consideration for false-positives. The system requires a moderately complex wake-up gesture sequence to prevent you from, say, accidentally turning on the stereo when you roll over in bed.

If you’re having trouble wraping your mind around this, consider this ultrasonic music player. The WiFi version does the same thing, but processing changes in the returning radio waves is much more complex.

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One Man’s Adventures In Custom Keyboard Development

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As a software developer, [suka] spends a lot of time every day in front of a keyboard. He had been trying out different keyboard layouts far less common than even the moderetly obscure Dvorak layout, and after some time decided a custom ergonomic keyboard was what he wanted. His progress of designing his own custom ergonomic keyboard is a fascinating read, made even cooler by the fact these are real, professional-quality keyboards with mechanical switches and custom enclosures.

After starting off with a few USB numpads, [suka] dove in to the world of Cherry switches by crafting his own wing-style keyboard. [suka] works for one of the larger manufacturers of laser-sintering machines, so he was able to create the enclosures for his keybaord – as well as the key caps – fairly easily. The technology behind laser sintering allowed [suka] to create some strange bowl and trough-shaped keyboards before settling on his daily driver, seen above.

The Blue Cube, as [suka] calls it, includes an integrated stand, an integrated IBM trackpoint mouse, and is powered by a Teensy microcontroller. [suka]’s keyboards might not be heafty enough for melee combat like the venerable IBM Model M, but it’s exactly what [suka] wants, and that’s just fine by us.

Add External Power To Any USB Hub

[Andrew] was getting some poor performance from a couple of USB devices he had connected through an unpowered hub. This is a problem because the hub prevents devices from negotiating with the host controller for more current. He fixed it by adding an external power supply to his USB hub.

In this case the PCB already had a footprint for a power connector. The manufacturer uses one board for several different models and just leaves the supply components unpopulated. [Andrew] managed to find a barrel jack in his parts bin that matched the footprint.

One important thing to do before hooking up the source is to disconnect the 5v wire from the incoming cable from the computer. The other tip we can give you is to use a good regulated 5v source to ensure you don’t damage the stuff you’re trying to power. That means avoiding deals that are too good to be true.

One Game Controller Connects To Many Consoles

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[Dave Nunez] wanted arcade quality controls when gaming at home. The problem was he couldn’t decide on just one console to target with his build, so he targeted them all. What you see above is a single controller that connects to many different gaming rigs.

He took a simple-is-best approach, keeping the main goal of high-quality inputs at the forefront. To start, he built the face plate out of thick MDF to ensure it wouldn’t flex or bounce as he mashed the buttons. To keep the electronics as simple as possible he soldered connections to actual controller PCBs (well, reproductions of controllers), breaking each out to a separate DB9 connector on the back of the case. These connectors interface with one of the three adapter cables seen to the right. This lets the controller work with NES, SNES, and an Atari 2600 system.

To pull the enclosure together [Dave] designed the rounded corner pieces and cut them out with a CNC mill. These connect with flat MDF to make up the sides. To give it that professional look he filled the joints with Bondo and sanded them smooth before painting.

Auto Dimmer Hacked Into Keyboard Backlight

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As the title says, [José Faria] added the ability to adjust his keyboard backlight based on ambient light levels. But that’s just one of the things he did during his hacking extravaganza with this Razer BlackWidow Ultimate.

When he first received the peripheral he didn’t like the blue LEDs used as backlights. So he removed all of them and put in white ones. He doesn’t talk too much about that but we’d image it was a ton of work. The new color was pleasing, but then the ability to adjust their brightness started to irritate him. There are four predefined levels and that’s all you get. Even the GUI which has a slider for adjustment couldn’t go outside of those levels.

His solution was to augment the controller with his own. He patched in an AVR chip to the transistor which controls the low side of the LED circuits. While at it he also noticed that the keyboard case was actually translucent. This let him hide a photosensor inside which automatically adjusts the light levels. But he did it in a way that still allows him to use the original functionality with the flip of a switch. See for yourself after the break.

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