A new robot developed by scientists at MIT promises to increase the safety of gas systems by locating leaks in pipe lines with increased rapidity and ease.

Researchers from MIT and King Fahd University of Petroleum and Minerals (KFUPM) in Saudi Arabia have developed a self-propelling robotic system which is capable of swiftly and accurately detecting gas leaks by monitoring pressure changes alongside pipe lines.

According to Dimitrios Chatzigeorgiou, a mechanical engineering PhD student at MIT and lead author of the research paper, his team has "proved that the concept works," and is capable of detecting leaks in gas pipes, water pipes or petroleum pipelines which are as small as one to two millimetres in size, even at a comparatively low pressure.

The use of pressure-based sensors compares favourably to conventional methods for finding leaks in pipeline, which involve the use of above-ground acoustic sensors to detect the vibrations or dim sounds which leakages produce, and the occasional use of video cameras to scrutinise pipes for visible ruptures.

Such methods are highly laborious and time-consuming in nature, require skilled operators, and often prove incapable of finding smaller breaks or leakages. According to Chatzigeorgiou, the acoustic method is also inapplicable to plastic pipes, which dissipate sounds too quickly for detection purposes.

The new pressure-based method devised by Chatzigeorgiou is capable of detecting leakages in any pipeline systems while also operating with extreme swiftness.

The device currently consists of two chief components - a compact self-propelling robot which uses wheels to traverse the length of pipes, and a pressure sensor consisting of a drum-like membrane which forms a seal around the pipe. When the device runs into a leak, the membrane is distorted by the change in pressure, triggering force-resistive sensors which sent an alert via a wireless communications system.

The top speed of the device is nearly five kilometres per hour, but this limit is imposed by the speed of the robot's propulsion system and more rapid detection remains a possibility.

The drum membrane is sensitive enough to detect tiny leaks a mere tenth or even twentieth the size of those that can be uncovered via acoustic sensing methods, and can relay their location with pinpoint accuracy.

robot pipe

"This technology allows for an unambiguous and reliable sensing of very small leaks that often go undetected for long periods of time," said Kamal Youcef-Toumi, a professor of mechanical engineering at MIT and a co-author of the research paper.

The device could also prove to be more affordable than conventional leakage detection systems, which remain relatively expensive and can cost as much as $250,000 to monitor 100 kilometres of pipeline a year.

Should the method enjoy broad application, it could prove a huge boon for industry given the peril posed by leaking gas lines which create the potential for explosions, as well as the wastage of oil or natural gas they produce.

The team of researchers has already entered discussions with gas and water companies for conducting field trials in real-world conditions, and have plans to adapt the system to pipelines with variable diameters.