A three-axis force fingertip sensor based on fiber Bragg grating

Fiber Bragg grating (FBG) based force sensing technology receives much attention from various research communities in robotics. In this paper, we investigate a three-axis FBG force sensor for robot finger. A special separated elastic structure with six FBGs attached has been designed for three-axis force sensing. Strain distribution and dynamic performance of the proposed structure are simulated by using finite element analysis (FEA). Six FBGs with different wavelengths were arrayed along a single fiber and divided into three groups to measure Fx, Fy, and Fz, respectively. The experimental results demonstrate that the sensor possesses good linearity, weak coupling, and creep resistance.