For the Practical Use of a Lamb Wave-based SHM System

We have been developing a Lamb wave-based structural health monitoring system which can contribute to achieve cost reduction of aircraft maintenance, more efficient operation of aircraft in airlines, and future design improvement for aircraft manufacturers. In our SHM system, Lamb waves are generated and measured with micro actuators and optical fiber sensors, which are installed in aircraft structures. When damages initiate and grow in a structure, Lamb waves which propagate thorough the structure are influenced and changed by the damages. By analyzing the changes of the measured Lamb waves, the SHM system can detect the damage in the structure, consequently, can evaluate structural integrities. We have conducted several verification tests, taking the environmental effects into account so far. In this paper, investigation results of simulation on propagation behavior of Lamb waves and results of flight tests were reported.