Bluetooth is one of the mainstays of the mobile gadget world, allowing mobile devices to communicate easily over short distances. It’s how your wireless headset talks to your cell phone without the complexity and power requirements of WIFi. In particular, the Bluetooth Low Energy (BLE) component is interesting for those who build portable gadgets, because it requires a very small amount of power. Continue reading “Hackaday Dictionary: Bluetooth Low Energy”
[Matt Reed] works at a pet friendly work-space, where his pooch called [Bean] loves to wander around and disappear. She’s not getting in trouble, but nonetheless, [Matt] worries about her. So he took the creepy stalker route and put a beacon on her collar to track her every move.
He’s using a small BLE beacon that will poll a signal every second, sending out a unique ID code and a RSSI value (Received Signal Strength Indicator). Normally beacons are placed in a stationary location to help people navigate — but this time, it’s on a moving dog.
In order to better understand [Bean’s] location in the office, [Matt] set up three Raspberry Pi’s with Bluetooth adapters around the office. Using Noble, Node.js listens for the RSSI values and triangulates [Bean’s] position, much like a cellphone can be located using different ping times from cellular towers.
Continue reading “Office Dog Triangulation Keeps Spot Accounted For”
[Brian] managed to resist the draw of the Left Shark costume and went as a cyberpunk for Halloween this year. Among his costume’s props was a small, one-handed chording keyboard that fit easily into one of his pockets. Now he could have just glued a couple of key caps to something small and called it a day. Instead, [Brian] made a fully functional and modular chording keyboard that can communicate over Bluetooth or USB.
What is a chording keyboard, you ask? Instead of entering keystrokes one at a time, a much smaller set of keys are mashed in meaningful combinations called chords. Once you know what you’re doing, it’s much faster than a standard keyboard. If you’ve ever seen a court reporter hammering away on a tiny machine, you have seen a chording keyboard in action. Our own [Elliott Williams] covered the topic in detail over the summer.
[Brian]’s keyboard has seven keys, one for each finger and three for the thumb. Any key found on a standard 104-key can be made by pressing a combination of keys with the fingers in relation to the center, near, or far thumb keys. We’re pretty impressed that he was able to stuff all of that hardware in such a small 3D-printed package. It’s based on an Arduino micro and uses an Adafruit EZ Key for Bluetooth communication with a phone or tablet.
The ultimate plan is to make this into a wrist-mounted chording keyboard that extends or retracts with the flick of your wrist. [Brian] has made some progress on this, having developed and printed the mechanism. But as you can see in the video after the break, adding the keyboard to it is just too much for the hobby servos he chose to move. Still, if he can dial it in this is going to be awesome!
The keyboard also has an ADXL335 accelerometer breakout, which means it can function as a tilt mouse. Neither the Bluetooth nor the tilt mouse functionality are imperative, though—if you want to make your own and leave either of these out, there is no need to alter the code.
Like many programmers, [Daniel Nugent] loves his old mechanical keyboard (a WASD Code Keyboard). What he didn’t love was the cord. Sure, you can get a modern wireless keyboard, but it won’t be the same as the keyboard you’ve spent so much time with. Armed with a Bluetooth Low Energy (BLE) module, a rechargeable battery and some coding, he kept his keyboard but got rid of the wires.
Although he has some specific handling for the WASD, the code would very likely handle any PS/2 keyboard. The PS/2 interface is a simple synchronous serial port with a single clock and single data line. Handling it with a microcontroller isn’t very difficult.
Last January, [DrYerzina]’s sister couldn’t find her cat. The family searched the neighborhood for two hours until the cat came out from underneath a bed, proving once again cats own humans, not the other way around. A solution to this problem would come in the form of technology, specifically as [DrYerzinia]’s entry for the Hackaday Prize, a solar-powered Bluetooth tracking device. Yes, you can go on Amazon or eBay and buy a BLE tracker, but this version comes in a handy package: it’s built of a flexible circuit board to fit just about everywhere, including on the collar of a cat.
[DrYerzina]’s Bluetooth tracker is built around an Bluetooth LE module, with a few added passives, LEDs, and other parts glued and soldered onto a double sided, flexible PCB. To this, he’s added a flexible solar cell and a flexible LiPo battery. All of this is stuffed inside an enclosure 3D printed in flexible filament.
While the Hackaday Prize is filled with wearables, [DrYerzina]’s project is at the forefront of hombrew wearable technology. Nowhere else in the prize have we seen a dedication to making a device that bends. The best part is, he’s actually building a useful device; with just 15 minutes of sunlight a day (a condition very likely for a sleeping cat), this Bluetooth tag can work for weeks.
We have seen a few projects that convert a rotary dial for use with modern technology, but this one adds a new twist to the mix: it uses Bluetooth 4.0. [Silent] used a Nordic Semiconductor NRF51 DK development board for the project, which was built from the Nordic SDK source code for creating an HID (Human Interface Device). After what he claims was an hour or so of hacking, he was able to get this Arduino-compatible SoC dev board to detect the pulses from the rotary dial, then pass the appropriate number to a connected device as a key press. This means that his design should work with any device that has Bluetooth 4.0 support. It is powered from a big dry cell because, to quote [Silent], “small coin batteries are not hipster enough”.
It’s a simple project, and we have seen rotary cell phones before, but this still is ripe for expansion. You could either use a smaller, cheaper version of the Nordic chip at the center of this hack, as most of the dev board features aren’t used. Or you could do some more hacking, add support for the Bluetooth HSP headset profile, then wire it up to a vintage phone for the most hipster Bluetooth headset ever. We can’t wait until we see a hipster sitting in a coffee shop banging away on a typewriter and answering this. Get to it, people!
Everyone’s heard of the “World’s Smallest Violin,” but we think it’s time for something more upbeat. [Simone Giertz] of Punch Through Design has created a mini electric ukulele using a LightBlue Bean. The Bean is an Arduino-compatible microcontroller that you can wirelessly program using Bluetooth low energy (BLE).
The ukulele’s frame is made of laser-cut plywood. Four 1M ohm resistors are soldered to individual wire strings. A different set of wire strings in the ukulele’s neck are connected to the same ground as the Bean. In order to play this tiny instrument, a finger must be kept on the “ground” strings while the other “tone” strings are touched by a different finger. [Simone] uses Arduino’s Capacitive Sensing Library to determine which string is being touched and what the tone will be (indicated in Hz). A piezo buzzer provides the sound. There is no need to fret when the battery is depleted from using this at an all-night luau: the frame can be unscrewed with easy access to the battery. [Simone] has uploaded the Bean’s code to GitHub.
There’s no shame going solo, but we’d enjoy a show of dueling mini-ukuleles. A duet with the 3D-printed ukulele is always a possibility. Or, play this little guy while running up and down some piano stairs while the kettle fife blows off some steam. It’ll be a musical way to brighten anyone’s day. Check out the video of the mini ukelele after the break. You can also see more of [Simone’s] work at her website.
Continue reading “Create A Buzz With The Mini Electric Ukulele”
