Slip and roughness detection of robotic fingertip based on FBG

The function of slip and roughness detection is important for dexterous manipulation robots. In this paper, we designed a slip sensor for robotic fingertip based on FBG (Fiber Bragg Grating). Firstly, the structure was designed and analyzed with simulation of FEA software. It was proved that the structure can detect shear deformation when slip occurred. Then, several experiments of slip and pressure have been carried out. The signal when the kinetic friction just occurred was extracted for incipient slip recognition. Second derivative algorithm was proposed and result showed it can distinguish incipient slip effectively. At last, the slip sensor was slid on different surfaces to obtain stable kinetic friction signal. Surface recognition algorithm was studied based on kNN. According to the signal amplitude caused by vibration, this sensor can distinguish different surfaces. The slip sensor shows the feasibility of slip and roughness detection and has the potential applications in intelligent robotics.