Bikelangelo: the Graffiti Maker Bike

On this Instructable, I'll share all the resources you will need to create your own Bikelangelo and become the coolest protestor of your town.

It’s inspired in the classical persistence of vision (POV) projects, but has been modified to control electrovalves instead of controlling LEDs. I implemented a simple system with some magnets to coordinate valves' speed with the speed of the bike. Also, I added a Bluetooth receiver so as not to depend on the computer to send the sentence to be written.

I’ll divide the process on three main parts:

• Electronics
• Paint tank and painting system
• Structure

Bill Of Materials:

Electronics:

• Arduino nano.
• Hall effect sensor.
• Bluetooth module (HC 05).
• 8 channel relay module 5v.
• 12v battery.

Paint tank and painting system:

• 7x Electrovalves (12v).
• 8x bike valve (recycled).
• 7x garden sprinkler.
• PVC tubes and joints, I used a 160mm as main tube for the tank.
• Air pump.
• Flexible tube.

Structure:

• It’s up to you. I used PVC tubes but I think that's not the best option. I recommend making it metallic, but you can use any material and dimension that fixes to your needs.
• PVC glue.

First, I made the paint tank. This part is so important and you should glue it carefully, because once you glue it together you’ll not be able to fix it.

I don't have sketches of the design, but you can get the idea from the video above so you can adapt it to your needs.

The same happens with the structure. You can get inspiration from mine, but there are no sketches so you will also have to adapt it to your needs.

You can download the arduino sketch and the wiring diagram from my github profile:

github.com/sagarrabanana/Bikelangelo

First of all, you'll need to fill the paint tank with paint or water to the half of its capacity. Then close the tank and pump air in to create the pressure.

Once the mechanical part is ready, you must send the sentence you want to write via "Serial Bluetooth Terminal" app. You have to end the sentence with a '&' to tell the Arduino that's the end of the sentence. Otherwise, it will stay waiting for it. When the Arduino receives the sentence, it will let you know by turning on a LED on the pin 13.

After this, you just have to start cycling and the machine will start painting automatically.

Good luck!
I'll be glad to help you if you have any doubt!