AquaFly Project: Autonomous Multi-Drone Water Sampling with a Payload Deployment and Retraction Mechanism.

The article focuses on the AquaFly project, a collaboration between the University of Toronto Institute for Aerospace Studies (UTIAS) Flight Systems and Control Laboratory and Queen's University Biology Department, which developed autonomous unmanned aerial systems (UAS) for multi-drone water sampling. Two custom-designed octocopter UAS, each equipped with a novel ratchet and pawl payload deployment and retraction mechanism, enable safe, stable, and efficient collection of 1-liter water samples from remote or inaccessible water bodies along pre-programmed flight paths. The system supports simultaneous multi-drone operations to reduce sampling time and improve data consistency, demonstrated through successful autonomous flight tests over various lakes. This approach addresses limitations of traditional and existing drone-based water sampling methods by eliminating the need for drone landing on water, onboard pumps, and fixed payload heights, thereby enhancing operational safety and efficiency in environmental monitoring.