Sea and flight trials of optical fibre Bragg grating strain sensing systems

A description of the development and practical deployment of an optical fibre Bragg grating strain sensor system for structural monitoring is given. The system has evolved through practical trials involving sailing yachts and a turbo-prop driven aircraft. This paper gives an account of the strain sensor system which uses parallel fibre channels with multiplexed Bragg grating sensors in each. The sensors are interrogated using a combined broad band light source and tunable optoelectronic filter. Sensor update rates of 500 Hz per sensor for up to 40 sensors were achieved. The deployment of two systems based on this architecture are described: the first in a luxury `superyacht' in which Bragg sensors were embedded within its 35 m carbon fibre mast; the second in a Jetstream aircraft where surface bonded Bragg grating strain `rosettes' were flown under extreme conditions.