Development of a novel probe for remote visual inspection of pipework

The interior visual inspection of pipework is a critical inspection activity required to ensure the continued safe, reliable operation of plant and thus avoid costly outages. Typically, the video output from a manually deployed probe is viewed by an operator with the task of identifying and estimating the location of surface defects such as cracks, corrosion and pitting. However, it is very difficult to estimate the nature and spatial extent of defects from the often disorientating small field of view video of a relatively large structure. This paper describes the development of a new visual inspection system designed for inspecting 3 - 6 inch diameter pipes. The system uses a high resolution camera and structure from motion (SFM) algorithm to compute the trajectory of the probe through the pipe. In addition a laser profiler is used to measure the inner surface of the pipe and generate a meshed point cloud. The camera images are projected onto the mesh and the final output of the system is a photorealistic 3-D model of the internal surface of the pipework.