Arduino Light Bar, Brake Lights and Indicators for Any RC Car

For my current year 10 electronics assignment we are required to power an existing RC car with an Arduino. The goal is to make autonomous cars that utilise multiple sensors to navigate and have many accessories, all without damaging the cars structure (eg no drilling holes or cutting wires). After figuring out how to make the car move and navigate autonomously as well as add RGB under glow and other accessories it was time to add a light bar that only turns on during the night (this tutorial will not teach you how to make it turn on during the night. After making the light bar I then decided to make brake lights and indicators with the idea that that would work appropriately with the autonomous functions. You may want to use this method to create police lights or lights for other vehicles such as trucks and heavy machinery. The following tutorial will tech you the basics of wiring up the LED's and turning them on and off, please keep in mind that resistors should be added to the LED's, but i'm too lazy for that minor detail stuff...

Step 1: Getting Started

There is a few things to do before you start soldering and coding. Firstly You must design a type of housing for your LED's, I made a simple CAD drawing and 3D printed mine. Once you have 3D printed a design it is very likely your LED's won't fit like mine. I fixed this by using my schools mini drill press and a 5mm drill bit. After I drilled out the holes the LED's fit nice and snug. The only thing left to do was insert the LED's in an order you choose. I would recommend cutting back the LED pins, although make sure you keep the cathode (-) shorter then the annode (+). One you've made a housing and inserted the LED's, you are ready to move on to step 2!

Step 2: Soldering the Ground Terminals

To solder all of the ground terminals I cut a wire to length (silly me cut a red wire for this) and stripped the ends. The brake lights positive pins were bent and soldered to the negative terminals to minimise wire clutter. I then grabbed the wire that I previously stripped and soldered it to the negative (ground) terminals. After all this I soldered on a 200mm wire to the end of the ground wire to allow me to connect the system to an Arduino.

Step 3: Soldering the Signal/positive Wires

After the grounds were soldered I soldered a 200mm positive wire to the remaining pin on each LED. A positive wire was soldered to the left indicator, brake lights and right indicator.

Step 4: Soldering and Insulating Jumper Wires

To complete the hardware I cut 20mm of the end of male jumper wires, 3 red and 1 black. Small heat shrink tube was slid onto the wires before I soldered the jumper wires to the light bar wires. Once this was soldered I insulated the connections with the heat shrink tube to avoid shorts.

Step 5: Testing

Once the hardware was complete I tested everything with a 3 volt battery pack... Keep in mind the each LED requires 2 volts and if they are in series they require 2 volts each, so the 3 brake lights require a total of 6 volts to power and the 5 LED light bar requires 10 volts.

Step 6: Code and Test

I will attach the code below, it is fairly straight forward. If you are unsure how to upload code to an Arduino board there is many YouTube tutorials which teach you in about 2 minutes. Thanks heaps for following my Tutorial!

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/* Arduino RC car light bar and brake lights
* By Edward Robinson, Australia

* This is a basic demonstration code...

* Some suggestions would be to use a 3 axis accelerometer to automate the turn signals and brake lights or even connect the lights to an existing Arduino car project and remotely control the lights

* Try adding delays or flashing the lights, or even making police lights :)

* I am personally using this for a school project, controlling an existing RC car with an Arduino and adding a range of sensors and accessories

* Thanks for downloading my code!

*/

int lightBar = 13;

int brakeLight = 12;

int leftIndicate = 11;

int rightIndicate = 10;

void setup() {

pinMode(lightBar, OUTPUT);

pinMode(brakeLight, OUTPUT);

pinMode(leftIndicate, OUTPUT);

pinMode(rightIndicate, OUTPUT);

}

void loop() {

digitalWrite(lightBar, HIGH);

digitalWrite(brakeLight, HIGH);

digitalWrite(leftIndicate, HIGH);

digitalWrite(rightIndicate, HIGH);

}