0-3 Barium Titanate-PDMS Flexible Film for Tactile Sensing

Abstract

Lead free BaTiO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> -PDMS piezoelectric composite thin films are fabricated with simple process. Composite films are prepared by dispersing 20, 30, 40, and 50 wt% of BaTiO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> in cross-linked PDMS matrix. Corona poling of the films is performed to improve the piezoelectric properties of the films. Piezoelectric properties of the films are studied by measuring the charge developed across the thickness of the film under a compressive force. A 50 wt% poled BaTiO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> -PDMS film has shown a piezoelectric charge constant of 178 pC/N and achieves a dielectric constant of 4.59. Tensile tests indicate that these films are very soft and flexible with low Young’s modulus. A 50 wt % poled BaTiO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> -PDMS film film has shown a Young’s modulus 3.92 Mpa. The film generates charge across the film proportional to the finger pressure applied on them. Thus it demonstrates effectiveness for tactile sensing. As a tactile sensor a 50 wt% poled film shows a sensitivity of 38.34 kPa <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−</sup> 1. High charge response for tiny forces makes the composite a good candidate for tactile sensing applications such as robotic skin and touch pads.