s paper presents a new sensing methodology for
the automated inspection of pipes. Standard inspection systems, as
they are for example used in waste pipes and drains, are based on
closed-circuit television cameras which are mounted on remotely
controlled platforms and connected to remote video recording facilities.
Two of the main disadvantages of such camera-based inspection
systems are: 1) the poor quality of the acquired images
due to difficult lighting conditions and 2) the susceptibility to error
during the offline video assessment conducted by human operators.
The objective of this research is to overcome these disadvantages
and to create an intelligent sensing approach for improved
and automated pipe-condition assessment. This approach makes
use of a low-cost lighting profiler and a camera which acquires images
of the light projections on the pipe wall. A novel method for
extracting and analyzing intensity variations in the acquired images
is introduced. The image data analysis is based on differential
processing leading to highly-noise tolerant algorithms, particularly
well suited for the detection of small faults in harsh environments.
With the subsequent application of artificial neural networks, the
system is capable of recognizing defective areas with a high success
rate. Experiments in a range of waste pipes with different diameters
and material properties have been conducted and test results
are presented.