An automatic impact monitor for a composite panel employing smart sensor technology

Impacts can inflict serious damage on composite structures. For structures on the surface of an aircraft this has potentially critical consequences. The problem is exacerbated by the fact that the damage is internal, with little or no indication on the surface of the structure, making it difficult to detect. A potential solution to the problem would be an impact monitoring system that could detect when an impact occurred. This idea was explored using a composite panel, inside which a SMART Layer was embedded. Two techniques were studied that were able to estimate the locations of impacts on the panel from the measurements provided by the piezoelectric strain sensors in the SMART Layer. The first technique employed artificial neural networks and the second used a triangulation procedure incorporating a genetic algorithm. The knowledge acquired during the study made it possible to develop a simple and efficient prototype impact monitoring system for the composite panel.