3D shape sensing with FBG-based patch: from the idea to the device

In this work, the advantages of 3D printing technology are combined with fiber Bragg grating (FBG) sensors to implement an innovative 3D shape sensor embedded in a 3D printed patch. The system allows to obtain a sensing patch able to provide a direct measure of curvature and neutral axis position in the 3D space in a simple manner and without requiring numerical simulations or mathematical models of the structure of interest. The experimental tests assess the proposed novel approach showing an optimal agreement between the measurements of the proposed patch with respect to the reference sensors. Furthermore, both the curvature sensitivity and resolution can be modulated by changing the distances among the FBGs inside the patch, tailoring the performances and the dimensions with the application requirements.