Real-time through-thickness and in-plane strain measurement in carbon fibre reinforced polymer composites using planar optical Bragg gratings

Abstract A new strain sensor is proposed which can measure both through-thickness and in-plane strains within a laminated fibre-reinforced composite material. The planar sensor uses novel embedded planar optic sensors and is demonstrated on a carbon fibre composite test coupon. The planar optical sensor was fabricated via flame hydrolysis deposition and was physically machined to reduce the substrate thickness to