Parallel Fin Ray Soft Gripper with Embedded Mechano-Optical Force Sensor

Abstract

The rapid advancement in soft robotics over the past decade has driven innovation across the industrial, medical, and agricultural sectors. Among various soft robotic designs, Fin Ray-inspired soft grippers have demonstrated remarkable adaptability and efficiency in handling delicate objects. However, the integration of force sensors in soft grippers remains a significant challenge, as conventional rigid sensors compromise the inherent flexibility and compliance of soft robotic systems. This study presents a parallel soft gripper based on the Fin Ray effect, incorporating an embedded mechano-optical force sensor capable of providing linear force measurements up to 150 N. The gripper is entirely 3D printed using thermoplastic elastomers (TPEs), ensuring a cost-effective, scalable, and versatile design. The proposed sensor architecture leverages a gyroid lattice structure, yielding a near-linear response with an R2 value of 0.96 across two force regions. This study contributes to the development of sensorized soft grippers with improved force-sensing capabilities while preserving the advantages of soft robotic manipulators.