Soft force sensor based on silicone rubber embedding single mode fiber using Brillouin optical correlation-domain reflectometry

We propose a distributed optical fiber sensor embedded in a silicone rubber block for potential application to soft robots. The system uses Brillouin Optical Correlation-Domain Reflectometry (BOCDR) to measure the strain distribution along a single fiber embedded randomly in three dimensions. Compression experiments were conducted in both the x and y directions, revealing distinct strain patterns for each orientation. The results confirm the feasibility of capturing multi-axial deformation using a single fiber, and the silicone block demonstrated reversible deformation with minimal hysteresis. This approach provides a promising sensing platform for soft robotic structures requiring flexible and distributed strain measurements.