Bluetooth is among the most widely accepted ways for two devices to communicate with each other. Every phone, tablet, and laptop comes with Bluetooth built in, as do several peripherals. So with a little do-it-yourself (DIY) tinkering, you can do some wonderful things with this technology.
For any project in this list, you will need to know the basics of DIY electronics and have the necessary tools at hand. Some projects require specialized tools, as noted. And of course, always remember to take all the necessary safety precautions before you begin.
The basic project you need to master is setting up Bluetooth on an Arduino microcontroller, and making it talk to another Arduino board wirelessly. Martyn Curry has an excellent step-by-step guide for this, connecting two Arduino boards as master and slave.
Naturally, you’ll need two Arduino boards and two Bluetooth receiver modules for this. To begin, start with his basic tutorial where he teaches you how to remote control an LED light on the slave Arduino via the master Arduino.
Then move on to the more advanced project, where the slave gauges the temperature outside and sends the signal to the master inside, which in turn displays the reading on a screen.
This might be the easiest and most useful project to start with. With an Arduino board, a few wires, and an LCD screen, you can type text on your phone and display it on the screen. Just like that, you’ll have a wireless notice board.
This project requires no soldering or any advanced skills, you will only be connecting cables to parts. Even the code for the Arduino board is ready to download, and there’s a handy Android app you can grab from the Play Store. The whole thing should take no more than half an hour, and is the ideal way to get started on DIY electronics projects.
If you have a pair of old wired headphones that have broken, don’t throw them out. This cool DIY tutorial shows you how to turn them into wireless headphones by adding a Bluetooth, while also giving you a new plug to connect a standard 3.5mm cable.
You’ll need a mini Bluetooth receiver, adapters for a DC jack and a 2.5mm to 3.5mm jack, and that pair of old headphones. You’ll also need a soldering iron and a multimeter, both of which you can find at any hackerspace.
In the project, you will be taking apart the headphones and the receiver, and then soldering them together. Then you fit everything into the speaker, make a hole for the 3.5mm jack and the charging cable.
Most car stereos today come with Bluetooth, but if you have an older car, you’ll need to figure out other ways to play music from your phone to the car stereo. Generally, a simple Bluetooth FM transmitter can get the job done. But that means you get an extra device in the car, instead of an invisible Bluetooth car stereo. For the DIY enthusiast, there’s a better way.
The stereo in your car actually has enough space in it to add a Bluetooth module. It costs about $10 on eBay. All you need to do is pry open the stereo, hook up the module, and do a bit of soldering.
A few people who tried this also said they managed without soldering, but it would depend on your car stereo model. And well, nothing against the original uploader, but you might want to read our guide to soldering before you try and copy him.
Unlike a car, there is no stereo for your two-wheeler. But hey, Patrick Panikulam has figured out a way to upgrade a motorcycle helmet by adding Bluetooth speakers inside it.
You’ll need old headphones and a Bluetooth receiver module to take apart, a 3.5mm audio male pin, and some thin flat wires. And of course, a full-face helmet. It’s actually a pretty easy hack to put together, with minimal soldering and some make-do adjustments like sticking the speakers with double-sided tape.
But while this adds some much-needed features, remember, safety first. Don’t text and drive, don’t turn up the volume such that you can’t hear others, and generally do everything you can to keep your attention on the road.
Who doesn’t love a good remote controlled toy? Instead of going to the store to buy one, you can actually make your own RC car with an Arduino board and Bluetooth.
For this project, you’ll need a custom PCB designed by the maker. You can order it directly from EasyEDA or download the bill of materials and schematics to make your own. It’s probably wiser to order it.
Along with that, you’ll need an old RC car’s chassis as well as the cheap Arduino Nano, and other odds and ends like the Bluetooth module. This project requires some soldering too, so be ready for that. Once you’re done, install the Android app on your phone and start zooming around everywhere with your remote controlled Bluetooth car.
Wouldn’t it be cool if you could open a lock with your phone? The Bluetooth padlock is awesome, but it is also the most advanced project in this list. It requires some special equipment like a milling machine, a 3D printer, a laser cutter, and other things that you will find in your school or a local hackerspace.
Don’t be intimidated though. The maker, Kirand1, has written a clear set of instructions that take you through the steps of creating a housing, the shackle and locking pin, the faceplace, and then inserting the electronics (based on an Arduino board).
The final version will let you lock and unlock the padlock with the tap of a button on an app. It even works on a smartwatch.
Beware of Bluetooth Flaws and Security Risks
As convenient as Bluetooth technology is, it has a few flaws that you need to know about. In fact, the open and common nature of the wireless standard makes it a routine target for miscreants. If you’re doing any of these Bluetooth DIY projects, please read about Bluetooth’s security risks.