USV with Interfacial Pumping for Efficient Microplastics Removal
Stephan Wagner, Yicong Fu, Sunghwan Jung, Kirstin Hagelskjaer Petersen
AI summary
Problem
Traditional surface trawls suffer from hydrodynamic resistance that diverts flow around filters, making microplastics collection inefficient. There is a critical need for low-cost, scalable methods to actively draw surface water into filters without mixing it with the bulk.
Approach
The researchers mounted a bio-inspired, undulating interfacial pump on a small pontoon USV to actively suction surface water and microplastics into an onboard filter while the vehicle moves.
Key results
- First in-motion characterization of an interfacial pump on a moving USV
- Low thruster output paired with moderate pumping frequency maximizes energy-efficient particle capture
- Pontoon cross-section geometry critically dictates intake flow and filtration efficiency
- Pump maintains far-field suction without bulk mixing during forward motion
Why it matters
Offers a scalable, energy-efficient blueprint for deploying distributed autonomous platforms to monitor and remove microplastics from aquatic environments.
Abstract
Microplastics that accumulate at the air–water interface pose urgent ecological and health risks. However, existing sampling and collection methods based on surface trawls are hindered by hydrodynamic resistance. We present the first in-motion characterization of an interfacial pump mounted on a small uncrewed surface vehicle (USV) to actively draw surface water into an onboard filter. Experiments combining thruster-driven forward motion with the undulating pump show that low thruster output and moderate pumping frequency maximize particles captured per unit energy, balancing the ram effect of forward speed with the lateral suction of the pump. Scaled towing tests reveal that the pontoon cross-section strongly influences intake flow, indicating that streamlined profiles can further boost filtration efficiency. Finally, flow- visualization confirms that the pump’s ability to generate far- field suction without bulk mixing—previously demonstrated only in static tests—persists while the USV is in motion. These results establish interfacial pumping as a promising bio-inspired strategy for manual and autonomous microplastics collection, and highlight design parameters that can guide future devel- opment of distributed, high-coverage sampling platforms.