A vison-based system for mapping the inside of a pipe

Underground pipes constitute the backbone of the infrastructure of a country. Dirty, broken, or clogged pipes have direct implications on the health hazards of humans. It is therefore no surprise that fault assessment of pipes is an important topic, which has received considerable attention in the past. While most pipe analysis systems rely on active sensors such as laser or sonar, the use of passive vision sensors has advantages in terms of cost and safety. This paper presents an automated 3D pipe reconstruction system using a single monocular camera as the only sensor. The contribution of our work is threefold. Firstly, the paper analyzes the implications of different environmental conditions on the result of the 3D reconstruction. Issues like different texture, diameter size, and lighting conditions are addressed. Secondly, while previous vision-based techniques use a special type of fisheye camera to perform the reconstruction, the method presented here is implemented using a regular off-the-shelf camera. Thirdly and finally, the 3D reconstruction system is the first to be able to detect and localize obstructions inside a pipe. Experiments are performed inside real pipes and results prove the success of our techniques.