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”
There are a ton of apps out there for taking notes and recording ideas, but sometimes the humble pen is best. However, if you have the tendency to lose, crumple, or spill caffeinated beverages on your pen and paper notes, having a digital copy is quite nice.
The NoteOn Smartpen by [Nick] aims to digitize your writing on the fly while behaving like a normal pen. It does this by using the ST LSM9DS0TR: a 9-axis inertial measurement unit (IMU). These inertial measurements are processed by a STM32 Cortex M4F processor and stored on the internal flash memory.
To retrieve your notes, the Nordic nRF8001 Bluetooth Low Energy radio pairs the MCU with a phone or computer. The USB port is only used to charge the device, and the user interface is a single button and LED.
The major hardware challenge of this device is packaging it in something as small as a pen. Impressively, the board is a cheap 2 layer PCB from OSHPark. The assembled device has a 10 mm diameter, which is similar to that of ‘dumb’ pens.
The NoteOn doesn’t require special paper, and relies only on inertial measurements to reconstruct writing. With the hardware working, [Nick] is now tackling the firmware that will make the device usable.
The project featured in this post is a quarterfinalist in The Hackaday Prize.
There’s a lot more to those fancy radio modules you use with your Arduino projects than meets the eye. Many of them are systems on a chip, complete with their own microcontroller and memory that can control your entire blinking LEDs project. Developing for these radio modules is a bit of a challenge, as the IDEs and compilers cost several thousand dollars. [Tim]’s entry for the Hackaday Prize looks at one of these Bluetooth LE modules – Texas Instrument’s CC2540 and CC2541 – and puts an embedded BASIC interpreter right on the chip.
[Tim]’s inspiration for this project came from looking at a few popular devices using the CC254X chip. Many of these included a microcontroller and the added costs, complexity, and power requirements that come along with an additional chip. This radio module could easily run any code an ATMega could, and adding another chip to a product seemed like a terrible waste, and certainly not in the spirit of open hardware and software.
The alternative is writing an interpreter for the CC254X chip. He’s chosen BASIC, but added a little bit of Arduino language syntax to make it even easier to develop on. Having already run through a few successful tests involving SPI, I2C and 1-wire devices, [Tim] has a basic system working, but [Tim] admits it does need a little rework to make it easier to use.
It’s a great project, and personally astonishing that it didn’t make the quarterfinal selection for The Hackaday Prize. [Tim] is still working on his project, though, in a great example of extrinsic motivation; he doesn’t need a trip to space to convince him to build something cool.
You can check out [Tim]’s two minute concept video below.
This project is an official entry to The Hackaday Prize that sadly didn’t make the quarterfinal selection. It’s still a great project, and worthy of a Hackaday post on its own.
Continue reading “Extrinsic Motivation: BASIC For Bluetooth”
No, not real birds! [Kyle] works in operations at a web company and needed a way to send alerts to his fellow coworkers, so he modified a flock of Audubon Society plush birds to respond to a Bluetooth beacon.
Using NRF24L01+ Bluetooth Low Energy modules, [Kyle] installed one each in these battery-powered singing birds. The devices are presumably powered off of the battery that comes with the birds, but the use of the BTLE module means the batteries won’t discharge as rapidly.
[Kyle] also built an API that works over HTTP or IRC, which means that the employees in the office can activate everyone else’s birds over a simple and intuitive interface. The birds can be activated one at a time, or all together in “panic” mode as one giant flock (in case of an emergency in the office). They can also be activated one at a time on a specific hour to simulate the Audubon Society’s bird call clock.
He calls the device equail and it’s a very unique notification system with a lot of applications. All of [Kyle]’s code and documentation of his project are available on his github site. He also used this primer on BTLE to get started, and this guide on sending data over BTLE to help get the project in the air.
What is better than making your own smart watch? Making one with an OLED display. This is exactly what [Jared] set out to do with his DIY OLED smart watch, which combines an impressive build with some pretty cool hardware.
When building a DIY smart watch, getting the hardware right is arguably the hardest part. After a few iterations, [Jared’s] OLED smart watch is all packaged up and looks great! The firmware for his watch can communicate with the PC via USB HID (requiring no drivers), contains a “watch face” for telling time, includes an integrated calendar, and support for an accelerometer. His post also includes all of the firmware and goes into some build details. With the recent popularity of smart watches and wearable electronics, we really love seeing functional DIY versions. This is just the beginning. In the future, [Jared] plans on adding Bluetooth Low Energy (BLE), a magnetometer, a smart sleep based alarm clock, and more! So be sure to look at his two older posts and keep an eye on this project as it unfolds. It is a very promising smart watch!
With Android L including support for smart watches (in the near future), it would be amazing to see DIY watches (such as this one) modified to run the new mobile OS. How great would it be to have an open hardware platform running such a powerful (open source-ish) OS? the possibilities are endless!
A little more than one month ago we featured a Kickstarter campaign that was raising quite a lot of eyebrows and over half a million dollars. This particular product was a battery-free tag meant to be attached to anything you may lose in your daily life. It was supposed to communicate with Bluetooth Low Energy (BLE) devices and have a 200ft (60m) detection range.
The main claim was that the iFind could harvest enough power from existing RF fields inside a typical home environment to operate for centuries. As Kickstarter just cancelled its funding a few minutes ago it seems that the basic maths Hackaday did a while ago were correct and that the project was in fact a scam. We’ll direct our readers to this particular comment that sums up all the elements pointing to a fraudulent campaign and show you the email that the backers received:
A review of the project uncovered evidence of one or more violations of Kickstarter’s rules, which include:
- A related party posing as an independent, supportive party in project comments or elsewhere
- Misrepresenting support by pledging to your own project
- Misrepresenting or failing to disclose relevant facts about the project or its creator
- Providing inaccurate or incomplete user information to Kickstarter or one of our partners
Putting aside this news, this campaign’s cancellation raises a bigger question: why didn’t it happen before and how could we control Kickstarter campaigns? On a side note, it’s still very interesting to notice the nearly religious fervor of the sunk cost fallacy that such campaigns create in their comments.
Thanks [Rick] for the tip!
[Vishak] tipped us about the iFind Kickstarter campaign, a 1.25×1.06×0.09″ (32x27x2.4mm) tag meant to be attached to anything you may lose in your daily life. This device communicates with Bluetooth Low Energy (BLE) enabled smartphones, has a 200ft (60m) detection range and a loud alarm. What is interesting to mention is that this device doesn’t need any battery to operate as it
recycles electromagnetic energy and stores it in a unique power bank.
As you can guess, this particular claim intrigued the Hackaday team given that we never featured so small energy harvesting devices. The ‘closest’ thing that comes to our minds is the Allsee project, a simple gesture recognition device that uses existing wireless signals (TV and RFID transmissions) to extract any movement that occur in front of it. However the antenna was quite big and very little power was extracted.
A quick Google search let us know that Bluetooth Low Energy solutions usually consume an idle current of around 10uA @ ~3V. The (very) successful Sticknfind campaign which promoted the same battery-enabled product claimed a one year autonomy with a CR2016 battery and a 100ft range, leading to a ~90mAh/24/30.5/12 = 10.2uA idle current. As we’re not expert on the subject, we would like to ask our readers if they ever came across such energy harvesting performances (3V*10.2uA = 30uW) in a normal home environment. Our very bad maths indicate that if one would like to extract power from a typical Wifi router located 2 meters from you emitting 0.5Watts of power (in a perfect vacuum environment) with a 32*27mm = 864mm = 0.000864m² tag you’d only be able to get 0.5 * (0.000864/(4*pi*2*2)) = 8.6uW.
It is therefore too bad that we can’t see in the presentation video what is inside the iFind, nor more details about the patent pending technologies involved. We hope that our dear readers will enlighten us in the comments section below.