Fingertip-controllable pulling force sensor

This study designed and realized a flexible and transparent tactile sensor with simultaneous normal, shear, and pulling forces detection. The detection ranges take consideration of real controllable forces from human being fingertips. The sensitivity is 0.33, 0.23, and 0.37 pF/N, and the sensing range is up to 1.4, 2, and 1 N respectively for normal, shear, and pulling forces, which are proper for human being finger control [1]. The transmittance is higher than 80% in the visible region. It is believed that a sensor which can simultaneously detect normal, shear, and pulling forces is a significantly advance step toward 3D image control or 3D display of next-generation touching system.