Researchers at MIT (Massachusetts Institute of Technology) have developed a new leak detection system, one which uses a robot to inspect pipes from the inside to find leaks before they have time to become catastrophic.
The new leak detection system can inspect gas and water pipes. Significantly, it works “no matter what the pipe is made of”. Many other leak detection systems, on the other hand, don’t work well in systems that use wood, clay or plastic pipes – materials used in the majority of pipes in the developing world, according to an MIT statement.
MIT professor of mechanical engineering Kamal Youcef-Toumi and graduate student You Wu have been developing and testing the new system for nine years. This summer, further tests will be carried out on the 12” concrete water-distribution pipes under the city of Monterrey, Mexico. In September, Youcef-Toumi, Wu, and two colleagues will describe the system in detail at the IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS) in September.
How does it work?
A small, rubbery robotic device that looks like a badminton shuttlecock can be inserted into a water system through any fire hydrant. It then moves passively with the flow, logging its position as it goes. It detects even small variations in pressure by sensing the pull at the edges of its soft rubber skirt, which fills the diameter of the pipe.
The device is then retrieved using a net through another hydrant, and its data uploaded. A key advantage of the system is that it doesn’t require any costly, disruptive digging. As well as the passive device that is pushed through the water by flow, the team has also developed an ‘active’ version that can control its motion.
PipeGuard, the MIT team behind the project, now intends to commercialise the robotic detection system to help alleviate the huge amounts of water lost each year due to leaks. With sponsorship from King Fahd University, the system has been tested in Saudi Arabia, where some 33% of drinking water produced at the desalination plants is lost through leakage.
The tests, in pipes with many bends, T-joints, and connections, involved creating an artificial leak for the robot to find. The robot did remarkably well, distinguishing the characteristics of the leak from false alarms caused by pressure variations or changes in pipe size, roughness, or orientation.
“We put the robot in from one joint, and took it out from the other. We tried it 14 times over three days, and it completed the inspection every time,” Wu said in the MIT release. “What’s more, it found a leak that was about one gallon per minute, which is one-tenth the minimum size that conventional detection methods can find on average, and a third as large as those systems can find under even the best of conditions.”
The use of the new system is not restricted to water pipes. The team claim it could be used for other types of distribution systems, such as those for natural gas. Natural gas leaks are capable of producing deadly explosions, with gas leaks hard to detect until they become large enough to smell. PipeGuard was actually first developed for finding gas leaks, before being adapted to water systems.
Globally, water distribution systems lose an average of 20% of their supply through leaks. As well as contributing to water shortages, these leaks cause damage to buildings and roads, and can lead to pollution. Monterrey loses an estimated 40% of its water supply every year to leaks, costing the city about $80 million (€69 million).
An animation demonstrating the new system can be watched in the videos section of Fluid Handling International.