Robots have been developed for a wide variety of environmental issues, from exploring and monitoring the health of our oceans to cleaning solar panels and wind turbines. A new robot created by researchers at the University of Bristol has the mission of cleaning ponds and lakes. Powered by the microbes it scoops up from the water and digests, it doesn't need any recharging to keep going.
The Row-bot is inspired by the water boatman insect and uses a similar mechanism to glide across the surface of water -- in the robot's case, a paddle powered by a 0.75 Watt DC motor. Both bug and robot maximize surface area when making a power stroke and then minimize surface area during the recovery stroke to have the most efficiency.
The robot also features a "stomach" that houses a microbial fuel cell (MFC) that runs on bacteria extracted from the water and feeds electricity to the motor. Within the MFC, the bacteria is broken down into carbon dioxide, protons, and electrons which the fuel cells uses to generate electricity.
The robot ingests some water from the lake or pond it's floating on and then the fuel cell generates electricity from the bacteria in the water. This provides enough energy for a few strokes of the paddle. As it glides across the water, more water is taken into the "stomach" and the process keeps repeating, letting the Row-bot move around the water continuously.
The parts were created using a 3D printer for the frame with an elastic membrane stretched around the body. The next steps are adding monitoring and control systems that would allow the robot to be used for environmental sensing and clean-up projects. In the future, the Row-bots could be deployed in bodies of water to monitor for pollution or pathogens and then, outfitted with the right tools, immediately take steps to remove pollutants or improve the water quality.