4WD Obstacle Avoidance Robot using Arduino Uno

This paper describes the development of a four-wheel-drive autonomous obstacle avoidance robot designed using the Arduino Uno platform. The system utilizes an ultrasonic distance sensor mounted on a servo motor to actively scan the surrounding environment and identify obstacles in multiple directions. Based on the measured distances, the robot selects a safe path and navigates autonomously without human intervention. A micro-step motion technique is implemented to achieve slow and controlled movement without employing PWM-based speed control. A regulated power supply using a buck converter ensures stable operation of the controller and sensors. Experimental evaluation in indoor environments demonstrates reliable obstacle detection and effective navigation performance, making the system suitable for educational and research applications.