#14advanced

Smart Gate

Automated gate control combining sensors with a servo motor

Watch the circuit build itself: components drop in, wires connect, and the output comes alive.

Components

Everything you need for this project.

SG90

1x SG90 servo motor

1x HC-SR04 ultrasonic sensor or push button

2N2222

1x 2N2222A transistor

1KΩ

1x 1KΩ resistor

1x 1N4148 diode

+100µF

1x 100µF capacitor

6x jumper wires

How It Works

Servo motor control, combining sensors with actuators, conditional logic, system design, and closed-loop control concepts.

InputUltrasonic / Button
ProcessingESP32-S3 detects approach, controls servo angle
OutputServo gate opens/closes

What You Build

Servo on D1 acts as gate, ultrasonic/button on D2/D3 detects approach. Gate opens automatically when someone approaches.

African Context

Automated gates and barriers are common in compound housing and parking lots. This teaches actuator control: the bridge between sensing and physical action.

What You'll See

Approaching the sensor (or pressing button) swings the servo 90°. Gate closes after a timeout. Display shows gate state and distance.