APPLICATION OF BRAGG GRATING SENSORS IN THE CHARACTERIZATION OF SCALED MARINE VEHICLE MODELS

Experiments using two different fiber-optic Bragg grating strain senso r systems to measure dynamic loads, slamming forces, and bending momen ts on a scaled catamaran model are reported. The system designed to me asure slamming forces is based on dynamic locking of the laser diode w avelength to the peak wavelength of a Bragg grating mounted in a force cell. The sensor system has a dynamic range of 27 dB (1-550 N) and a bandwidth in excess of 1 kHz. For the measurement of bending moments, a time-domain multiplexing system, which used a unique pulsed rf modul ation technique, of two Bragg grating sensors mounted on a steel beam was designed. The dynamic range of this system was also 27 dB [17 Nm ( Newton meter) with a 0.03-Nm resolution]. The bandwidth was limited to approximately 50 Hz. (C) 1997 Optical Society of America