Introduction: Bluetooth RC Car: Part 1
In this tutorial you are going to learn how to hack a remote controlled car with an Arduino Uno so you can control it with your phone via Bluetooth. Using an Arduino allows other features to be added like a tail light, or a speaker. The wonderful thing about this system is that it a platform so you can add other features to the car. This is only part 1 because we were just focusing on getting the car to move since neither of us have ever done anything like this before. Part 2 should be coming closer to the end of the year, as we plan on working out a way to get two of these cars to interact with each other, either by command or autonomously.
Get to hacking, and good luck.
- Small Screwdriver
- Soldering Iron with solder
- Wire Stripper
- 1 RC Car
- 1 Arduino Uno
- 1 Small Bread board
- 1 Bluetooth Chip (link here)
- 1 H-Bridge(link here)
- 3 LEDs
- 1 9v Battery and connector
- Electrical Tape
Recommended, but not required:
- Wire wraps
- U Shape jumper wires
Step 1: Breakdown and Prep
The first order of business is to take your sparkly new RC car and tear it apart. More preciously, you need to get to wherever the circuit board is on the car. I won't be going through this part, since it can vary depending on which RC car you purchase.
Now's the time to start getting your soldering iron warmed up. While you're waiting for that find a piece of paper and mark down which wires do what. you can also cut several segments of wire to use as extensions to the wires on the car.
Once the iron's hot and your done taking notes go ahead and un-solder all of the wires from the board and attach extensions to any of the wires that you think need one.
Step 2: Wiring It Up
So here's the tedious part. For the most part, the board should be wired up following the diagrams here, however, using in using this setup we ran into some problems with power output in regards to the motors. I've noted the changes that we made on the first diagram. The second diagram is just to make it clearer which wire goes into which spot on the H-bridge.
We use the H-bridge here to allow for the motors to both draw from a separate power-source from the arduino itself, as well as to be able to reverse the current flow to allow the motors to spin both ways.
To know if it is all wired up correctly, when the car is turned on and the 9v is plugged in, the device should beep and light up. One important thing to take note of is that the Bluetooth chip should have some flashing lights on it. If not, that means that it is not receiving power and you won't be able to connect to it.
Step 3: Programming It
Now for the code. Unfortunately, if you were looking for an in depth about the code that goes into this, we don't have it. Neither of us know much about coding yet, and that wasn't our focus (at least for part 1). You can check out here for the full code (which I've also provided here) with an explanation. If you don't care, just take all of the files, open them in the arduino software, and compile them to the board.
Step 4: Does It Work?
First, head on over to here and download this app. This will allow you to control the car from your phone if everything is working.
Plug all of the power connectors into the board if you've removed them and turn on the car. You should get lights and a beep if its wired correctly, as stated in the last step. Like mentioned before, make sure that the Bluetooth chip is blinking.
Once you've checked all of those things, grab you're phone and pair it with the Bluetooth device named "HC-06". We've found that this doesn't always work, so just open up the app and press the "Bluetooth" button and pair your device from that menu instead. After that, the onscreen controls should control your car.
Step 5: Conclusion
You still may run into some problems, though, considering that neither of us are too knowledgeable regarding both coding or wiring. We came to our final working model after an obscene amount of experimenting with our connections that can't be fully captured by this Instructable.
We apologize for the short and concise information, however, our sights are set on the second half of this project. Getting two cars to interact was our original intention, however, we had to scale it back and make sure we could even get the cars to work in the first place. Now that we know how to do that, we can move on to our lofty plans for interaction.
We sincerely hope you enjoyed this tutorial, and would love to see what you’ve done with your car, please share in the comments below and look forward to Part 2!
6 years ago
Great write up! How's the forward voltage on the L293D? I'm using an L298N motor controller and it drops a lot of voltage.
6 years ago
That's a neat way to mod it :)