Autonomous Systems Designed and Tested, for Aquatic Research

Abstract

Monitoring aquatic environments is critical for preserving biodiversity, mitigating pollution, and addressing habitat degradation. Traditional methods, such as manned vessels and stationary monitoring stations, are often resource-intensive, costly, and unsuitable for remote or hazardous locations. The increasing demand for scalable, efficient, and autonomous solutions has driven advancements in robotic platforms tailored for environmental inspection in diverse aquatic settings. This thesis addresses these challenges by developing two innovative, autonomous robotic platforms optimized for hazardous and inaccessible environments. The first, AquaTri, is a waterjet-powered trimaran designed for bathymetry, water quality assessment, and environmental inspections across lakes, rivers, and coastal waters. AquaTri weighs under 5 kg, costs $600-$1,500 USD, and employs off-the-shelf components and 3D printing for affordability and reproducibility. Its waterjet propulsion ensures maneuverability and resilience in debris-laden shallow waters, with testing confirming stable operation at speeds up to 2 m/s and effective obstacle avoidance. The second platform, AeroBuoy, is a lightweight, drone-deployable buoy designed for environmental monitoring in narrow and difficult-to-access river systems. Weighing just 3 kg and costing $800 USD, AeroBuoy autonomously navigates downstream using river currents at speeds of 0.5 m/s while collecting environmental data such as water temperature. Its compact, 3D-printed design facilitates rapid deployment and retrieval via drones, minimizing human intervention in dangerous areas. Testing demonstrates its robust self-righting capabilities and adaptability in real-world scenarios, including validation trials at Orewa River, Auckland, New Zealand. Through a detailed comparison of these platforms, this thesis evaluates their complementary strengths, limitations, and suitability for diverse environmental monitoring applications. By advancing efficient, low-cost solutions for aquatic research, this work contributes to the broader adoption of autonomous systems for environmental preservation and paves the way for future improvements in durability, autonomy, and sensing capabilities.