Tactile sensing for object identification based on hetero-core fiber optics

This paper describes a human-like tactile sensing method for object identification using a tactile sensor based on hetero-core fiber optics. The sensor performs for detecting tactile information in such ways both of gentle and heavy touch with the contact force applied ranging from 0.0 N to 5.3 N. The proposed method for object identification is intended to measure several types of tactile impressions such as surface features and physical characteristics in both scanning and pushing motions. It is found that the fabricated tactile sensor can detect surface features such as arranged bump dots and two types of textured fabrics by the sensor scanning on the surface. Moreover, it is confirmed that the sensor can measure the physical characteristics of touched materials, including the hardness in the range from 5° to 80° according to the Shore hardness A scale, as well as viscoelastic properties by assessing the temporal variation of the sensor response during stress relaxation.