A two-range tactile sensor integrated in three-layer elastomer based on FBG

Pressure perception is an important element for robot tactile sensing. We developed a two-range pressure sensor based on fiber Bragg grating (FBG) that can detect slight pressure with higher sensitivity, and can also adapt to a larger range of forces to sense. The sensor was designed by nesting two elastomers, which convert the pressure signal into a displacement signal and then turn into wavelength information under the processing of the bottom FBG that wrapped in silicone. This design makes the robot to cope with more complex and changeable environments. Moreover, the sensor unit has strong anti-interference ability which is applied to complex robot skin array sensing systems, because it is located in the inner layer that is divided into sensing part and signal processing part. This ranged sensor with three-layer elastomer has crucial practical significance for robot tactile.