Flexible micro-tactile sensor for normal and shear elasticity measurements

This paper presents a tactile sensor capable of in-vivo measurement of Young´s modulus and shear modulus of elasticity for soft tissue and other materials. The sensor is built by using polydimethylsiloxane as the structural material. A number of sensing cells of different stiffnesses are used in each sensor. The Young´s modulus of the targeted object can be measured based on the relative deflections of adjacent sensing cells. The shear modulus measurement is enabled by using a quad electrode structure in each sensing cell. Experimental results show sensing resolution of 0.1MPa for Young´s modulus measurement from 0.1MPa to 1MPa, and 0.05MPa for shear modulus measurement from 0.05MPa to 0.2MPa.