A highly sensitive multiplexed FBG pressure transducer based on natural rubber diaphragm and ultrathin aluminium sheet

•Multiplexed FBG, ultrathin aluminium sheet and low Young’s modulus natural rubber diaphragm as the sensing components.•A highly sensitive pressure transducer was recorded at 329.56 pm/kPa across 10 kPa with a good linearity of 99.76%.•The thermal cross-sensitivity of the pressure transducer is compensated. Pressure measurement with a good sensitivity has always been a concern in most of the engineering applications and biomedical field. In this paper, a multiplexed FBG bonded on an ultrathin aluminium sheet which act as a cantilever deflected due to a deformation from a natural rubber based diaphragm has been proposed and studied. By using two gratings inscribed on a single optical fibre which senses the positive and negative strain has enhanced the sensitivity of the pressure transducer recorded at 329.56 pm/kPa or corresponding to 10.7893 kPa−1 across the range of 0 to 10 kPa with a good linearity of 99.76%. Furthermore, the thermal cross-sensitivity is compensated.