3D-Localisation and Magnetic Mapping of Buried Pipelines Using Unmanned Aerial system (UAS)

Pipeline incidents related to third-party work around the world reached a peak last year. About 30% of reported incidents were due to poor pipeline geolocalisation (DIRT Report 2019). The integrity of pipeline networks is also at risk due to increased encroachment because of urbanization. As a result, some governments enforce stringent rules on pipeline operators concerning their network georeferencing. The currently available tools, which use electromagnetic or ground-penetrating radar technologies, are handheld and particularly challenged in remote rural locations, where constraints are related to the safety of field operators, specific soil and culture conditions, potential human errors in data interpretation, and time consumption (authorization, accessibility). UAS are often deployed in difficult-to-access locations as they present significant operational advantages in terms of operators’ safety, speed of execution, cost-efficiency, and access to impracticable terrains. Currently available technologies focus on above-ground measurements through various methods, such as thermal and hyperspectral imaging or Lidar. Skipper NDT has developed a proprietary embedded system and acquisition protocol that combines the advantages of a drone vector and high precision magnetometry. The technology allows Skipper NDT to provide information about the magnetic underground environment of the pipeline as well as an accurate and continuous 3D-localisation (longitude, latitude, and depth of cover). An extensive series of field trials were conducted in France. Europe’s leading gas pipeline operator, GRTgaz, qualified the georeferencing performances of the technology in the highest precision category (Class A, according to the French regulation), under various operational conditions.