Water pipe-inspection robot designed to have a light touch

The current 3D-printed prototype was created by Norway’s SINTEF research group (which has previously developed a wheeled pipe-inspection robot), along with Breivoll Inspection Technologies and industrial design firm Inventas.
It has an articulated segmented body, with propellers located at either end. While those props provide the power to move it, spring-loaded fins on its body do lightly brush against the inside of the pipe, just to keep the bulk of the robot from contacting it.
Depending on which prop is activated, the robot can move forward or backward through pipes as small as 10 cm (3.9 in) in diameter. It can travel up to 150 meters (492 ft) – making turns as sharp as 90 degrees as it goes – and then simply reverse back through the pipes to get to its starting point for retrieval.

Water pipe-inspection robot designed to have a light touch