Project 2.9.3: Mechanical Expression Display

Description	This project makes a servo motor rotate a simulated robot head while the RGB LED changes eye colors for expressive effects.
Use case	This project can be used in educational robotics, interactive exhibits, STEM demonstrations, and robotic companions to simulate expressive head movements and changing eye colors for enhanced human-robot interaction.

Components (Things You will need)

Building the circuit

Things Needed:

• Arduino Uno = 1
• Arduino USB cable = 1
• RGB LED module = 1
• Servo motor = 1
• Breadboard = 1
• Jumper wires

Mounting the component on the breadboard

Step 1: Place the RGB LED Module on the breadboard.

NB: Make sure all components are securely placed on the breadboard with correct orientation.

WIRING THE CIRCUIT

Step 2: Connect the Signal (Orange/Yellow) of the Servo Motor wire to Digital Pin 9 on the Arduino Uno using male-to-male jumper wire.

Step 3: Connect the VCC (Red) of the Servo Motor wire to 5V on the Arduino Uno using male-to-male jumper wire.

Step 4: Connect the GND (Brown/Black) of the Servo Motor wire to GND on the Arduino Uno using male-to-male jumper wire.

Step 5: Connect the Red (R) pin of the RGB LED to Digital Pin 3 on the Arduino Uno using male-to-male jumper wire.

Step 6: Connect the Green (G) pin of the RGB LED to Digital Pin 5 on the Arduino Uno using male-to-male jumper wire.

Step 7: Connect the Blue (B) pin of the RGB LED to Digital Pin 6 on the Arduino Uno using male-to-male jumper wire.

Step 8: Connect the GND pin of the RGB LED to GND on the Arduino Uno using male-to-male jumper wire.

Make sure to connect the Arduino USB cable to the Arduino board.

PROGRAMMING

Step 1: Open your Arduino IDE. See how to set up here: Getting Started.

Step 2: Type the following code in your Arduino IDE: #include <Servo.h>, const int servoPin = 9;, const int redPin = 3;, const int greenPin = 5;, const int bluePin = 6;,Servo robotHead; as shown in the image below.

Step 3: Type the following code in your Arduino IDE inside the void setup() function: robotHead.attach(servoPin);, pinMode(redPin, OUTPUT);, pinMode(greenPin, OUTPUT);, pinMode(bluePin, OUTPUT);, robotHead.write(90); as shown in the image below.

Step 4: Type the following code in your Arduino IDE inside the void loop() function: setColor(0, 0, 255);, for (int angle = 90; angle >= 0; angle--) {, robotHead.write(angle);, delay(15); }, delay(500);, setColor(0, 255, 0);, for (int angle = 0; angle <= 180; angle++) {;, delay(500);, robotHead.write(angle);, delay(15); }, delay(500); as shown in the image below.

Step 5: Type the following code in your Arduino IDE inside the void loop() function: setColor(255, 0, 0);, for (int angle = 180; angle >= 90; angle--) {, robotHead.write(angle);, delay(15); }, delay(1000);, void setColor(int red, int green, int blue) {, analogWrite(redPin, red);, analogWrite(greenPin, green);, analogWrite(bluePin, blue); } as shown in the image below.

Uploading the code

Step 1: Save your code. See the Getting Started section

Step 2: Select the Arduino board and port. See the Getting Started section

Step 3: Upload your code.

CONCLUSION

This project helps learners understand how to combine multiple components with Arduino to create more complex interactive systems and automation solutions.