EXPERIMENTAL RESULTS AND FINITE-ELEMENT MODELING OF AN EMBEDDED POLARIMETRIC SENSOR

'Smart structures' or 'smart skins' will require structurally integrat ed sensing systems that can operate in practical situations. Optical s ensing techniques are receiving considerable attention for the monitor ing of such systems. In this work an optical-fibre sensor has been emb edded, without removing its acrylate protective coating, in a glass fi bre-reinforced polymer. A single-ended polarimetric sensor was utilize d with a large dynamic range for strain measurements up to 2000 mu eps ilon, at which value the sensor failed. The optical measurements show good agreement with conventional electrical resistance strain gauge me asurements. Finite element modelling was used to investigate the stres s/strain distributions within the composite material and the embedded optical fibre. The modelling results show excellent agreement with the experimental results and suggest that the soft acrylate coating is de bonding, thus reducing the sensor's dynamic range.