Archive for the ‘general’ Category
I now have a working Windows application that can detect when someone presses the BDB-5000 Bluetooth Doorbell. It can be set to start up when Windows starts, and you can choose any MP3 file as the doorbell sound.
This is a screenshot of the configuration window, where you choose your own MP3 alert sound, the text that will appear in the alert window, and whether or not the app will start up with Windows:
This is a sample of the Alert window that pops up when someone presses the BDB-5000 Bluetooth Doorbell:
This app will get more polish before it goes live, but it has proved the concept that a Windows app can talk to the doorbell and that the doorbell can trigger custom sounds and alert windows to appear on a Windows machine equipped with Bluetooth. The code base used for this app may make the process of creating a Windows Mobile app a little easier.
As of now, we have a working Android app and a working Windows app. Hopefully apps for mac and Windows Mobile will come soon. An app for iPhone will be further away due to Apple’s restrictive policies requiring certification to interact via Bluetooth with custom hardware. We will be able to design for those policies better once funding is secured.
Today I was able to fully populate the printed circuit board for the version 0.0.3 prototype. The 2×3 pin header on the board is for the AVR micro-controller (an ATtiny2313). I was able to program the AVR via the header as planned and everything has tested out great so far. The previous prototypes used a breadboard friendly ATmega8515L in a DIP package.
There are a few issues with the board that I’ve noticed so far and plan to correct in future prototypes. The most obvious is that I used the wrong footprint for the resistors (or ordered the wrong size resistors) so they are mounted vertical instead of horizontal.
The next steps are to cut the necessary holes in the enclosure and mount the circuit board in it. I also plan to test the battery life with the new AVR chip and Bluetooth module. With this version, I’ve also added an LED charge indicator, so I will also measure how long it takes to reach a full charge.
The printed circuit boards for the latest BDB-5000 Bluetooth Doorbell prototype version 0.0.3 have finally arrived. They took longer to get here than I wanted, but you can’t beat the price of batchpcb.com for low volume prototype grade orders.
This picture shows the board, which I designed to fit in to the enclosure I showed in a previous post. Thankfully, all the mounting holes line up and it fits perfectly in the enclosure.
So far, I have only soldered two components on to the board for testing. Those are the Bluetooth radio (the white/blue module labeled RN-42) and a 6 pin header. In this picture the 6 pins have a red FTDI Basic board mounted to them which just slides on and off of the header pins for testing. The red FTDI Basic board will not be there permanently so it doesn’t have to fit in to the enclosure.
Both the FTDI Basic board and the Bluetooth radio module are available at Sparkfun.com
In prototype versions 0.0.1 and 0.0.2, I used a different Bluetooth radio made by Parani (the Parani ESD100V2). It worked well but had two issues that prevented it from being a perfect fit for this project.
One issue was that it cost $49.50 for one unit (that price would be lower if you ordered in high quantity). My new radio cost about $15 for one unit (and even that price would be lower in higher quantity). My goal with a future Kickstarter.com project is to raise enough money to order parts in high enough quantities to make the BDB-5000 Bluetooth Doorbell available as cheaply as possible to as many people as possible. This $35 price difference will make a big difference in the final price of the units.
The other issue is that with any Bluetooth radio I use for this application it will be necessary to put the radio in “sleep mode” when it’s sitting idle in order to save battery life. That means when you press the doorbell button, it will take some amount of time for the radio to wake up and send a command to the computer or phone. The Parini radio (used in the older prototypes) can wake up from sleep in “a few seconds” according to its documentation. And you can see from the v0.0.2 prototype demonstration video that it really does take a few seconds to wake up, which is not really acceptable. According to the documentation for my new Bluetooth radio, the worst case scenario is a wake up time of 5 milliseconds, which should be unnoticeable. It will take some time for me to send this radio through some testing to find out how this feature effects performance and battery life.
I have tested the board above after soldering the 2 components on, and I’m able to connect through USB to the FTDI Basic board and send serial data to the Bluetooth radio. I’m also able to connect via Bluetooth to the radio and receive information sent over serial. So it looks like we are in good shape so far. I’m sure the printed circuit board I designed will have some flaws that will get fixed in the next revision, but so far so good.
This video gives a little more information about the BDB-5000 Bluetooth Doorbell Version 0.0.2 prototype and it shows the custom Android application in action.
I have a new enclosure that I plan to use for the next prototype. It is much smaller than the one used for version 0.0.2 and has a cleaner mounting system.
The mount/holster would stay attached to your cube wall through the use of double sided adhesive strips or with screws where possible. After a day’s work, you could easily remove the BDB-5000 Bluetooth Doorbell from the holster and plug it in to your computer or USB charger to juice up the battery for the next day.
I’ve designed a printed circuit board that will fit in to this new enclosure and I’m awaiting its arrival (which will take a few weeks). Even if I decide not to use this enclosure for the final product, this will still give me the opportunity to test out the latest revision of my schematic and printed circuit board design.
You can find out more information about this enclosure here (http://www.okwenclosures.com/products/okw/smart.htm).
Through some basic testing I don’t think this enclosure is 100% perfect for the BDB-5000 Bluetooth Doorbell. The enclosure is not tight enough in the holster, which leads to the enclosure riding up in the holster after pressing on it moderately. I’ve reached out to OKW to offer remedies to this issue (by making slight modifications to the design or offering an alternative design), but I haven’t heard back from them. If you have better ideas for an enclosure design, please let me know.
This is a functional prototype of the BDB-5000 Bluetooth Doorbell that is portable enough to take to the office. The line coming from the top is rigged up to hang the doorbell on a coat hook that I have on my cubicle. The line doesn’t serve any other purposes (it’s not an antenna or anything so it won’t be required in the final version). The final version will be much smaller and will have a cleaner way to mount the unit to your cubicle.
The black plastic enclosure is just a hobby grade enclosure that I drilled holes in for my use. The box contains mostly the same components as seen in version 0.0.1, with the addition of a rechargeable battery and charging circuitry. I also made minor improvements to the electrical design.
The main large blue button is the same type of button that is used on arcade machines.
On the side, there is an on/off switch and a USB plug for charging. I can get a full day’s use out of one charge. This version uses a standard full sized USB connector. The final version will use a micro USB connector for the charging port like the one used by most Android and Blackberry devices.
I have more testing to do, but this prototype should be technologically close to the final product. It will allow me to do thorough hardware testing and it will be essential for testing new versions of the software that I will be working on for Android, Windows, and Mac.
This was my first attempt at proving that the BDB-5000 Bluetooth Doorbell project could be done. This is a simple setup on a breadboard using a Bluetooth module, a large battery pack, an AVR microcontroller loaded with custom code, and a custom Android app loaded on the mobile phone (a Droid 1).
Something a little more portable will be coming soon.
And here is a video of the BDB-5000 Bluetooth Doorbell version 0.0.1 in action. The alert can be heard and it can be seen in the outlined area on the phone’s screen.
The BDB-5000 Bluetooth Doorbell is a project I created in response to people never being able to get my attention while I was listening to music in my cubicle. I noticed that other folks had similar issues.
There have been cubicle doorbells (like this one at ThinkGeek) around for quite a while. They all assume that you can hear the person trying to get your attention. If you could hear them already, the doorbell is just really a silly form of entertainment.
However, the BDB-5000 Bluetooth Doorbell is designed for people who wear ear buds or headphones while listening to music in their cubes. Press the button and through the magic of Bluetooth (and a custom Android or Windows application) a sound will be heard through the headphones, alerting the person that someone needs their attention.
The project is still under development and I will be posting pictures and videos of my prototypes soon. Right now the project consists of a custom piece of hardware that I hope to make available to the public soon, as well as a custom Android application. I will be working on Windows and Mac applications soon.
The concept could easily be expanded on for uses outside of the cubicle. Like using it as a real doorbell at your home while listening to music around the house or in the back yard. You could also replace the typical doorbell button with other sensors (motion detection, beam breaking, temperature, light, etc.). The basic platform could have many uses.
I plan to start a Kickstarter.com project soon so that I can raise enough capital to order the necessary parts in large quantities resulting in a lower price for everyone.
Please feel free to give me feedback or offer suggestions on how the project can be improved. You can email me at email@example.com