A plastic-filtering robo fish has won a nature-inspired robot competition.

The robot floats by flapping its tail while keeping its mouth wide open to collect water and microplastics into its internal cavity. When the cavity fills, the robot closes its mouth, opens the gill flaps, and pushes the water out, lifting the bottom of the cavity. A fine mesh attached to the gill covers allows water to pass through but retains plastic particles. The 50 cm long Gillbert robot collects particles up to 2 millimeters in size. It also has built-in sensors to monitor turbidity and light levels underwater, and uses an IMU to track its movements in the water. The developer plans to improve the robot and increase its size.