Results and Discussion
An A4-sized (210 × 297 mm) flexible surface shape sensor (Figure. 1) was developed through our FE-integrated framework (Figure. S1). FE modeling is utilized for testing design parameters of the sensor prior to fabrication, wherein parameters such as sensor thickness, sensing element placement can be tuned depending on the intended application. The surface shape sensor utilized 29 sparsely distributed FBGs as the underlying sensing elements for measuring strain, which were subsequently used as inputs to train a model to reconstruct the 3D surface morphology of the shape sensor. A demonstration of the shape sensor’s response to different external stimuli is presented in Videos 1, 2, including shape reconstruction during hands-on deformation, and impact from water jet and small projectile beads. Shape reconstruction accuracy, repeatability and hysteresis tests were also performed on the developed shape sensor. The resulting performance is achieved through our hybrid approach of FE-based data enrichment and ensemble learning method, with details described in the sections below.