## Introduction: Paintball Printer

Hi and welcome to my very first instructable.

For my course , we had to create something revolving around the theme of digital streetart. The only requirements were that we had to work with an arduino.

For this project I created a prototype of a paintball printer. For this I wrote a little program which can convert small or (big) images into a series of points for the paintball sentry gun to fire, printing out the image on the wall. The street art angle is that the images are converted to a type of stencil.

## Step 1: Gathering All the Parts

For this project you need several parts. I divided them here into 3 categories.

Electronics:

• Arduino Uno ( or any other arduino)
• 3 Three standard servo's (no continuous rotation)
• Three capacitors, also the ones provided with the arduino starter kit. I used the 100µF ones.( http://arduino.cc/documents/datasheets/cap100uF.pdf )
• Couple of jumper wires
• A green and red LED.
• A couple of resistors ( I used 2.2k Ohms)

Hardware

• Couple of MDF sheets. I used 4mm thick ones for the base and the gears.
• Some woodscrews
• Some bolts and nuts ( needed to make the base for the gun)
• Paintball gun. I used a tipmann model (see picture)
• Laptop/ pc to run the software of course

## Step 2: The Software

For this project I used processing in combination with the arduino code.

I used serial communication to send the converted values of the converted images to the arduino.

First I calculated the number of white dots. I do this by scanning the pixels of an image and comparing the brightness of each pixel with a threshold. If the brightness is higher than the threshold, I make that pixel a white dot. I extrapolated and saved the x and y coordinates to an array and I send this array with serial to the arduino. The arduino then converts these x values to pan and tilt values and sets the corresponding servo's in the right position, moving the gun to the correct location. Once an x and y value are successfully placed, the trigger servo triggers and so on.

Below are my processing sketch and my arduino code. (There still are a lot places the code can be improved but It seemed fine for me).

The software only works for images which are 15 x 15 for now.

## Step 3: The Base for the Gun

For the gun we need to build a base.

For the pan unit I lasercut some gears out of some sheets of MDF (4mm thick) and attached the pan servo like this

(INSERT PICTURE HERE)

The pdf for the lasercut I used is attached.

For the tilt part of the base I used a piece of plywood 8.5cm wide and 42 cm high. I drilled a hole into the piece and fitted the tilt servo in like shown in the picture

I would suggest you would check http://projectsentrygun.rudolphlabs.com/make-your-own for a better guide.

## Step 4: Finished Product

And here is the finished product!