Visual/Laser Inspection

While person entry viewing is possible for larger underground assets, most underground utilities require remotely operated equipment to carry out inspections. This category comprises inspection equipment that operates with visual images (e.g. CCTV inspection) or requires line-of-sight for scanning methods (e.g. laser scanning). Laser scanning can be combined with gyroscopic tracking of the survey device and precise inclination measurements to build a precise model of the alignment and internal geometry of an underground pipe or tunnel. An operator may be in direct control of the scanning device – controlling what is looked at, zooming for detail, recording the assessment in real time. However, increasingly automatic data capture is carried out at higher speed and the interpretation is carried out later – also often using automated image analysis software for aspects of the assessment.