June 2, 2025
Description
This color-sorting machine was built as part of a guest lesson I gave to a group of 10-year-old primary school students.
The goal? Show them that technology can be both fun and functional, and inspire them to explore the world of electronics, 3D design, and automation.
The challenge was to create something real within a short timeframe — and what better task than the classic: sorting Skittles by color?
Of course, the kids immediately pointed out that they could sort candy faster by hand (smart little critics 😄),
but once they saw the machine in action — reading colors, rotating, and using servos to open trapdoors — their excitement was priceless.
This machine was designed in Fusion360, 3D printed on a Bambu Lab X1 Carbon, and controlled with an Arduino Uno R3 using a TCS3200 color sensor, stepper motor, and multiple servos via PCA9685.
I believe that every engineer, maker, and tech wizard should take the opportunity to inspire kids.
Projects like this show that technical skills can be used creatively and practically.
Our future as a sector depends on sparking interest in the next generation.
💬 If this project gets just one kid more excited about engineering... it's a win.
Please feel free to:
Rebuild it
Improve it (there’s a lot of room for that!)
Share it in classrooms, makerspaces, or just for fun
All 3D components in .STL and .OBJ formats
Demonstration video (linked below)
Wiring info & component pinouts (images)
For the Arduino Code visit Github:
https://github.com/RexoLudus/SkittlerSorter
Below is a list of parts used in this build. You can adapt or extend it depending on availability and use case.
| Part | Description | |
|---|---|---|
| Arduino Uno R3 | Main controller board | Link |
| TCS3200 color sensor | For detecting Skittles colors | Link |
| PCA9685 servo driver | For controlling multiple servos | Link |
| 7x Servo SG90 motors 180 | Used to open trapdoors | Link |
| 1x Servo SG90 motor 360 | Used for Skittlers buffer | Link |
| Nema17 Stepper motor | For rotating the turntable | Link |
| Steppen driver DRV8825 | For rotating the turntable | Link |
| Motor driver expansion board | For rotating the turntable | Link |
| Microswitch (KW11-3Z-1) | For turntable positioning | Link |
| 12V → 5v Power module | Power convertor for PCA9685 and Servo's | Link |
| 12v 2A Power supply | General power supply | Link |
| Female DC power plug | General power supply | Link |
| 2x Buttons (12mm) | For interaction or debugging | Link |
| 1x 51105 Bearing | For smooth rotation turntable | Link |
Includes a walkthrough of the machine, how it works, and the 3D design.
This was built in just a few days — it's far from perfect, but that’s the point:
Start, build, learn, improve. And most of all: inspire others.
🔩 Built with love, tech, and a lot of servo wiggles.
Let’s get more kids into tech! 💡
License:
MakerWorld Exclusive License