New and advanced mini-robot to work inside pipes

Beneath our streets is a labyrinth of pipes, made up of conduits for water, sewage and gas. Periodic inspection of these pipes for leaks, or repair, normally requires digging up sections of the pipe. The latter is not only expensive and cumbersome, but causes traffic disruption and inconvenience to residents in the area, as well as causing damage to the environment.

A team including Netta Cohen and Thanh Luan Nguyen, both from the University of Leeds in the UK, have developed a tiny robot that can navigate itself inside pipe networks, including the narrowest sections of them, and transmit images of damage or obstructions to human operators, much more efficiently than systems currently in use.

The new robot model is called Joey and he is capable of exploring real pipe networks completely on his own.

Joey is the first robot of its kind that can navigate pipes as narrow as 7.5 centimeters in diameter under its own power. Weighing just 70 grams, the robot is small enough to fit in the palm of your hand.

The interior of the water distribution pipes and those that carry wastewater to the sewage network is not only difficult to access but also constitutes a very hostile environment for a robot. As if that were not enough, the small size that robots must have to move through such narrow places poses the challenge of making the robots efficient enough with only very simple motors, tiny sensors and computers, and batteries that despite being equally tiny can energize the robot for a long enough time.

Joey’s locomotion is based on structures definable as “leg-wheels”, manufactured by 3D printing, which roll along smooth sections and stride over small obstacles.

The robot is equipped with a series of low consumption sensors that measure its distance to walls, corners and crossings between pipes. It also has navigation tools, a microphone, a camera and “spotlights” to film damage or obstructions in the pipe network and save the images.

Diagram of the main parts of the robot Joey. (Image: TL Nguyen, A Blight, A Pickering, A Barber, GH Jackson-Mills, JH Boyle, R Richardson, M Dogar, N Cohen)

Despite its sophistication, the cost of the robot is comparable to that of a mid-range robot vacuum.

In tests carried out so far with Joey, it has been shown that he can navigate within these mazes without relying on instructions from human operators. The efficiency of it has also been demonstrated by an experimental network of pipes that includes a T-junction, a left and right corner, a dead end at one end, and an obstacle. On average, Joey managed to explore approximately one meter of pipe network in just over 45 seconds.

The researchers found that the robot easily climbs up and down pipes with slopes as steep as real pipes. To test Joey’s ability to navigate muddy or slippery pipes, they also added sand and liquid dishwashing detergent to the inside of the pipes. The robot met this challenge again successfully.

Cohen and his colleagues discuss the technical details of their new robot in the academic journal Frontiers in Robotics and AI, under the title “Autonomous control for miniaturized mobile robots in unknown pipe networks.” (Font: NCYT by Amazings)