Obstacle-Avoiding Robot Car

Problem

Building a reliable foundation for autonomous navigation: the car had to detect obstacles in real time and make safe steering decisions without a computer or camera.

Solution

Implemented an obstacle-avoiding robot car using an Arduino, HC-SR04 ultrasonic sensors, and DC motors with an L298N driver. Logic runs entirely on the microcontroller with no external compute.

Process

1. Hardware: 2WD chassis, front-mounted ultrasonic sensor, motor driver, and power distribution.
2. Sensor fusion: multiple readings and filtering to reduce noise and false triggers.
3. State machine: FORWARD, TURN_LEFT, TURN_RIGHT, BACK_UP with timing and thresholds.
4. Tuning: threshold distances and turn durations for different speeds and environments.
5. Documentation: build log and code repo for reproducibility.

Tech

• Arduino (C++)
• HC-SR04
• L298N
• DC Motors
• Breadboard prototyping

Outcomes

• •Consistent obstacle detection and avoidance in indoor and outdoor tests.
• •Clear separation of drive logic and sensor reading for easy behavior changes.
• •Served as base for later projects (line following, Bluetooth control).

Images