DESIGN AND IMPLEMENTATION OF AN AUTONOMOUS UAV SYSTEM FOR TARGET-BASED PAYLOAD EJECTION WITH REAL-TIME OBSTACLE AVOIDANCE

Abstract

The current research presents the design, development, and testing of an autonomous quadcopter UAV capable of performing GPS-based precision payload ejection with dynamic obstacle avoidance in outdoor environments. Existing UAV platforms for such operations are either costly or dependent on manual control, limiting their accessibility for defense and research applications. This work develops an affordable autonomous system that navigates to a predefined GPS target and releases a payload without human intervention. The system is assembled on an F450 quadcopter frame using a Pixhawk flight controller running ArduPilot firmware for stable flight and waypoint navigation. A Raspberry Pi 4 serves as the companion computer running ROS2, handling obstacle avoidance logic and ejection control. Ultrasonic sensors detect obstacles in real time, triggering avoidance maneuvers when necessary. Payload ejection is activated automatically upon reaching the target GPS coordinates through a servo mechanism connected to the Raspberry Pi 4 GPIO pins. Communication between the Pixhawk and Raspberry Pi 4 is maintained via the MAVLink protocol, while mission planning is carried out using Mission Planner software. Outdoor flight tests confirmed the system's navigation accuracy, obstacle avoidance reliability, and ejection precision, validating the feasibility of low-cost autonomous UAV platforms for defense applications.