Sensing skin for condition assessment of civil structures

The technology facilitating condition assessment of civil structures is currently limited. This is mainly due to the lack of scalability of existing sensing solutions, as well as the difficulty to link sensor signals to prognosis. With recent advances in conducting polymers, it is now possible to deploy network of flexible sensors over large areas, at low cost. Here, we propose to use a novel sensing skin that consists of a network of soft elastomeric capacitors (SECs) deployed in an array form. Each SEC acts as a surface strain gauge transducing local strain into changes in capacitance. Using strain data facilitates the feature extraction task for structural prognosis. We demonstrate the capability of the technology at conduction condition assessment by extracting deflection shapes on a specimen equipped with the SEC network. Results show that the sensing strategy compares well against off-the-shelf strain gauges, and that it can be used to extract useful signal features.