FBG based shape sensing of a silicone octopus tentacle model for soft robotics

The shape sensing of a soft silicone octopus tentacle model using FBG sensors is presented in this paper. A polyimide thin film layer integrates FBG sensors is embedded into a soft silicone model as the strain limited layer for pneumatic actuation. The relation between the Bragg wavelength shift (BWS) value and the bending curvature of the soft silicone model is measured through the FBG calibration process. The curvature values of the soft silicone model at four bending shapes are calculated based on the BWS values and the interpolation algorithm. The reconstruction of the 3D shapes of the soft silicone model at different bending status are realized using the curve fitting function, and the correctness is verified. The results show that the error between the calculated and actual values of the bending curvature is no more than 2.1%, the proposed FBG-based sensing approach is effective for the measurement of the bending shape of the soft silicone model, it has application prospect in the field of soft robotics.