My son also wanted to have a firefighter truck painted on his wall. But since I had some electronics stuff on my mind which I wanted to try out anyway, I promised him much more than a painting.
The idea behind, is to have a somehow 3d painting, with lights, and more states of programming. I decided to go with this:
• Idle mode: all lights are off, but if the light sensor senses no light, the headlights go on 20% of their power
• Headlight mode: headlights go on 100%
• Action mode: all lights animated somehow like a real firefighter truck (see video)
Cycling through all actions is done with a touch sensor on the lower left part, near the wheel.
Step 1: Canvas and Form
First of all I tried drawing a truck and all the elements to be later implemented. My son approved every part of the project, so my motivation was maximised ;-)
I started with a normal painting canvas.
Had a lot of styrofoam plates lying around in the basement, cut them in the form I needed, and glued them on the painting canvas. Later I rounded all the corners with some sandpaper. Also for some more detail in the form, I applied some cardboard.
I new that I am gonna use spray paint to cover the styrofoam, and also have found out the hard way that spray paint eats right through the styrofoam. So first of all before continuing, I covered everything with 2 layers of wood glue with a brush.
Step 2: Spray Painting and Decoration
So I painted everything, red the truck, silver the front bar, black the inside and wheels, white and blue the sky.
Now the decoration part has begun. I gathered over time everything I could imaging fitting the painting: bottle caps, bottles, sticks, parts from old toys, etc.
For the sirens, wheels, headlights, etc I used plastic bottles. See the image what part of the bottle is used for what part.
I found an online service which creates customised registration numbers. I only printed them out and used them on the truck.
Step 3: Electronic Part
So lets put some light in the project.
• normal leds: 2 yellow, 2 red, 2 blue
• a programmable led strip (WS2812b)
• photoresistor - light sensor
• Atmega328p microcontroller - programming
• 7805 voltage regulator
• 10uF capacitor - stabilise 7805 output
• 10MO resistor - touch sensor
• PCB board
Starting with an arduino I tried out the electronic part as seen in the pictures. Have developed the code for all 3 programs and to cycle through them.
Then I moved the code on a ATmega328p, which is the same microcontroller used on the Arduino, just to minimize the cost and size of the electronic part of the project.
Then I moved everything on a PCB board and soldered all together. This is my first time soldering everything on a board. Used only dev breadboards until now. So be gentle with my soldering skills :-)
Step 4: Finished
Seeing my son sit in front of it and playing more then 10 minutes with it (yes, that's a lot of patience for him / his age) was all I needed to declare it a successfull project :-)