Fabrication and study of miniaturized soft pneumatic fingers

Abstract

In this study, a miniaturized soft pneumatic finger was proposed and successfully fabricated. The finger structure comprised an extensible Ecoflex finger, inextensible polydimethylsiloxane (PDMS) layer, and air channel with three expandable chambers. The extensible Ecoflex finger was molded using a 3D-printed mold and bonded with the inextensible PDMS layer to obtain a finger structure. The inextensible PDMS layer was used to enhance finger stiffness. To study finger properties, inextensible PDMS layers with different thicknesses were bonded with the extensible Ecoflex finger, and various sizes of expandable chambers in the extensible Ecoflex finger were developed. Miniaturized soft pneumatic fingers with a 0.65 mm-thick inextensible PDMS layer can exert 14.90 mN of force and achieve a bend angle of 56 under an applied pressure of 16 kPa inside the air channel. Finally, fingers were integrated as to create a small gripper to grab a salmon egg without causing any damage.