Kids OK with adultArduino NanoLevel 2/3
Colour-Sorting Robot Arm
A colour sensor reads each block and a 3D-printed arm drops it in the matching bin.

Kids OK, with an adult
DIY project. Children must build this only with an adult (16+ years) beside them at all times. Not suitable for children under 8 years.
Do not power the servos from the Nano 5V pin. Centre every servo at 90° before fitting the horns.
Strictly follow the description given with this video.
Video
The video link will be added here soon.
How it works
- The TCS3200 shines light on the block and measures how much red, green and blue comes back.
- The Nano decides the colour by comparing the three readings.
- Four servos move the arm: base turns, shoulder and elbow reach, gripper grabs.
- The arm drops the block in the right bin and returns home for the next one.
Parts you need
- Arduino Nano× 1Buy
- TCS3200 colour sensor× 1Buy
- 4× SG90 / MG90S servos (base, shoulder, elbow, gripper)× 4Buy
- 5V 3A power supply× 1Buy
Kit for this projectPrice on request
Get the kitWiring

PowerGroundSignal
| # | From | Connect to |
|---|---|---|
| 1 Signal | Sensor S0 | Nano A0 |
| 2 Signal | Sensor S1 | Nano A1 |
| 3 Signal | Sensor S2 | Nano A2 |
| 4 Signal | Sensor S3 | Nano A3 |
| 5 Signal | Sensor OUT | Nano A4 |
| 6 Power | Sensor VCC | Nano 5V |
| 7 Ground | Sensor GND | Nano GND |
| 8 Signal | Base servo signal | Nano D9 |
| 9 Signal | Shoulder servo signal | Nano D6 |
| 10 Signal | Elbow servo signal | Nano D5 |
| 11 Signal | Gripper servo signal | Nano D3 |
| 12 Power | All servo 5V (red) | 5V 3A supply + |
| 13 Ground | All servo GND (brown) | 5V 3A supply − |
| 14 Ground | Nano GND | Supply − (common ground) |
3D print files
- arm_base_turntable.stlPLA+ / PETG · 0.2 mm · 40% infillLink at launch
- arm_links_gripper.stlPLA+ · 0.2 mm · 50% infillLink at launch
Code
The tested Arduino / ESP32 code for this project will be posted here, ready to copy.