Wavelength multiplexed fibre Bragg grating system for high-strain health monitoring applications

We have developed and demonstrated a fiber Bragg grating strain gauge system for high strain applications using spatial and wavelength multiplexing. The system takes advantage of a priori knowledge about the strain levels and relative phases between the different sensor signals to accommodate many sensors per fiber in an application where we expect to measure several thousand microstrains. In combination with scanning Fabry-Perot filter interrogation, this principle has been utilized in the design of a system for health monitoring of a naval surface effect ship and the system has been used in long-term load monitoring on the vessel. (Author)