With the increasing size of the cities, the underground sewage infrastructure that supports them becomes more complex. Maintenance and inspection routines become harder to execute and the multi-layer structure makes it difficult to access certain parts which must be evaluated. Nowadays the assessment of concrete sewage systems is performed by humans operating equipment that requires direct contact with the concrete construction. This limits the evaluation only to spaces where both the person performing the assessment and the equipment fits.
The primary objective of the TISCALI project (Technology Innovation for Sewer Condition Assessment using Long-distance Information-system is to determine the constructive strength and stability of sewers using an in-pipe inspection robot. The robot uses the impact-echo method to excite the sewer with a prescribed energy and for a certain duration by the means of an impactor developed in Robotics and Mechatronics (RaM) group.
The goal of this bachelor assignment is to analyze and to compare the signals recorded by various sensors which are developed for vibration or acoustic signal measurement. To this end a selection will be made among sensors such as vibration accelerometer, laser vibrometer, microphone, microphone array and particle velocity sensor. The outcome of this assignment will help determining the most suitable sensor to be mounted on the in-pipe robot which will enable contactless assessment of the concrete structure. Measurements will be performed on different concrete samples and the data will be recorded and analyzed. Digital signal processing will enable meaningful interpretation of the data and correlation with the physical defects that will be artificially created in the support layer of the concrete structure as well as defects in the concrete structure itself.