Ocean Sensing: Self-Powered Aquatic Robot

Researchers in the United States have made a significant breakthrough in ocean monitoring technology by developing an aquatic 'bug' powered by bacteria. This innovative creation has the potential to revolutionize the way we collect data and monitor the oceans.

The US Defense Advanced Research Projects Agency (DARPA) initiated the Ocean of Things program, which led to the development of this groundbreaking aquatic robot. The team at Binghamton University in New York leveraged their expertise in microbial fuel cell (MFC) technology to power the robot, enabling it to operate efficiently in aquatic environments.

The research conducted by the team demonstrated power generation close to 1 milliwatt, which is adequate to support the robot's mechanical movement and various sensors. These sensors can track crucial environmental data such as water temperature, pollution levels, commercial vessel and aircraft movements, as well as the behaviors of aquatic animals.

To ensure a consistent supply of organic substrates for microbial viability, the researchers integrated a biomimetic Janus membrane with asymmetric surface wettability. This unique membrane design enables selective substrate intake, with one side being hydrophilic and the other hydrophobic. It allows the robot to extract nutrients from the water and retain them inside the device to fuel bacterial spore production.

Moreover, the robot incorporates stability mechanisms inspired by water striders, enabling it to move efficiently across water surfaces. By mimicking the movement of water striders, the robot utilizes a motor powered by microbial metabolism, enhancing its agility and maneuverability in aquatic environments.

Professor Seokheun “Sean” Choi, the director of the Center for Research in Advanced Sensing Technologies and Environmental Sustainability (CREATES), highlighted the adaptability of the bacteria powering the robot. He explained, “When the environment is favorable for the bacteria, they become vegetative cells and generate power. But when conditions are unfavorable, they revert to spores, extending the operational life of the robot.”

Choi emphasized the importance of further research to identify the specific bacterial species thriving in different oceanic regions. By exploring the combination of multiple bacterial cells, researchers aim to enhance sustainability and power generation. Leveraging machine learning techniques, they seek to optimize the bacterial species combination for improved power density and sustainability.

One of the key advantages of these aquatic robots is their mobility, allowing them to be deployed wherever necessary. This mobility represents a significant advancement over current stationary sensors, offering greater flexibility and adaptability in ocean monitoring efforts.

The next phase of development for these aquatic robots involves testing various bacterial strains to determine the most efficient energy producers under challenging oceanic conditions. This ongoing research holds promise for enhancing our understanding of marine ecosystems and improving ocean monitoring capabilities.

Sources: 10.1002/admt.202400426; www.binghampton.edu