The UK Has Created a Robot Fish That Eats Ocean Plastic

In the UK, researchers at the University of Surrey unveiled Gillbert, a robot fish developed from a winning concept in the university’s Natural Robotics Contest. The design was inspired and submitted by chemistry undergrad Eleanor Mackintosh, whose vision was to create a creature that swims through water while filtering out microplastics, much like how real fish use gills to extract oxygen.

Gillbert is approximately the size of a salmon, about 50 cm long, and swims by moving its tail. As it glides, it takes in water with an interior cavity. Once the cavity is full, it expels the water through fine mesh gills that trap plastic particles as small as 2 mm. The prototype even includes built-in sensors for tracking its movement and environmental conditions like turbidity, and it glows at night when deployed in dark waters.

Key Features & Performance

• Microplastic filtration: Captures particles as small as 2 mm
  
• Size & materials: 50 cm long, made of lightweight biodegradable materials safe for marine life.
  
• Sensors: Includes inertial movement unit (IMU), turbidity, and light-level sensors
  
• Night visibility: Built-in lighting enables operation and monitoring after dark
  
• Prototype control: Operated via remote control; future versions could offer autonomous navigation and finer filtration.
  

Self‑Powering Claim? A Misunderstanding

Several recent headlines claimed the UK fish “powers itself by digesting plastic”, no battery needed. However, credible technical sources clarify that Gillbert is still powered by conventional batteries, and it does not generate electricity from plastic consumption or internal digestion of pollutants. This self-powering version remains speculative and unsupported by current scientific evidence.

Real-World Context & Potential

Gillbert is a prototype, not yet deployed at scale. The University tested it in lakes and controlled waterways; full deployment is still in development. Gillbert earned praise as a proof of concept for bio-inspired environmental robots, blending public innovation with robotics research and the natural world.

Some reports, especially on social media, have also overstated capabilities: claims like collecting over 2 kg of microplastics in 12 hours or being deployed in conservation zones lack verification and are not supported by published technical data.

What’s Next for Gillbert?

Future versions could include:

• Autonomous, battery-free operation
  
• Swarming fleets monitoring coastlines
  
• Finer filtration and hydrodynamic improvements
  
• Energy harvesting from organic matter or microbial fuel cells (not plastic)
  

Dr. Robert Siddall, who developed the Natural Robotics Contest, emphasizes that technologies like Gillbert represent early steps toward scalable solutions. They offer both practical tools and educational insight into environmental robotics.

Final Thoughts

Gillbert showcases UK innovation through its combination of biomimicry, sustainability, and public-driven design. It filters microplastic pollution in a way that is safe and modular, and while the idea of “plastic-powered robots” remains more science fiction than reality, the core concept remains powerful: using robots that swim, sense, and clean our waters.