The robot's camera (bottom left) takes pictures of radioactive pipes while the 3D-printed Y-shaped valves propel it forwards (Image: Harry Asada/d'Arbeloff Laboratory)
Fancy a job swimming through the radioactive pipes beneath a nuclear reactor? Probably not if you're a human, but that's just what this spherical robot is designed to do.
Rather than using propellers or rudders for propulsion, the robot takes advantage of the strong water currents running through the pipes. Harry Asada and colleagues at MIT used 3D printing to construct a network of tiny Y-shaped valves on the robot's surface. They steer the robot in a particular direction by closing certain valves, sending a jet of water in the opposite direction which propels the device on its way Already."
Reactor inspectors currently monitor these pipes remotely by running an electric current through them to find corroded sections or using ultrasonic waves to identify cracks, but the robot can get a much closer view with its on-board camera that takes photos of the pipe's interior.
The original intention was to retrieve the robot from the pipes to examine the images, but Asada is now working on a laser communication system to transmit images through the water. This will allow the robots to be used as short-term inspectors that eventually break down from repeated radiation exposure.