Row-bot with mouth open. Credit: Hemma Philamore, University of Bristol/BRL
Urban areas have the potential to pollute water in many ways. Runoff from streets carries oil, rubber, heavy metals, and other contaminants from automobiles. Groundwater and surface water can be contaminated from many sources such as garbage dumps, toxic waste and chemical storage and use areas, leaking fuel storage tanks, and intentional dumping of hazardous substances. Air pollution can lead to acid rain, nitrate deposition, and ammonium deposition, which can alter the water chemistry of lakes.
Areas of Sustainability:
Energy, Water, Pollution, Safety, Health
- Inspired by the aquatic water boatman beetle, Researchers at the University of Bristol have created a 3D printed robot that can self-propel, or ‘row’, along the surface of lakes and ponds, consuming microbes as it goes. Since the row-bot is powered by the microbes it eats, it does not require any recharging, and has the potential to be used in environmental monitoring and water clean-up systems.
- When it is hungry, the Row-bot opens its soft robotic mouth and rows forward to fill its microbial fuel cell (MFC) stomach with nutrient-rich dirty water. It then closes its mouth and slowly digests the nutrients. In the cell, bacteria digest organic waste, and produce carbon dioxide as a by-product, as well as the protons and electrons needed to get the electrical circuit in the cell flowing. When it has recharged its electrical energy stores the Row-bot rows off to a new location, ready for another gulp of dirty water.
- For flotation, the machine has four little stabilizers. To move, there are two paddles in the middle of its body, which have flexible flipper joints to make sure they move efficiently and minimize drag. The row-bot paddles were made as a 3D printed composite structure with a rigid frame that supports an elastic membrane. This membrane can either stretch to increase paddle surface, or, thanks to an integrated hinge, change the angle of the attack on the part of the paddle that remains underwater during the recover story, thereby reducing drag and increasing overall efficiency. The researchers added that the rigid frame was 3D printed with VeroWhite acrylic based photo-polymer, whereas the membrane was 3D printed in TangoBlack.
- In this design, the row-bot generated more energy than it needed to keep refueling itself. That’s huge, and it means in the future, the answer to waste in the water might be sprinkling robots into the stream, and waiting until they eat all the garbage.
- Environmental and electrical engineers and scientists
- City governments
- The results of this research were recently presented in a paper at the 2015 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS) in Hamburg, Germany.
- The next steps will be to add monitoring, remote sensing, and control systems that would allow the row-bot to be used in environmental monitoring and clean-up projects. For example, they could be used to monitor lakes for pollutants or deadly pathogens, and if found, either deploy more row-bots or some other system to restore water quality.
- Investors should provide initial seed funding for converting the prototype into a production-ready tool.
- NGOs should enforce policy and regulation of water pollutant levels in city lakes and other water sources.
- City governments should issue public tenders for companies implementing water pollution solutions with focus on sustainable practices. This would allow companies funding projects like this one to have a market opportunity.