Stiffness-tunable robotic gripper driven by dielectric elastomer composite actuators

In this article, by utilizing the dielectric elastomer composite actuators (DECAs), we design and fabricate a stiffness-tunable robotic gripper. Firstly, the voltage-induced electromechanical deformation of the DECA is investigated by applying a ramping voltage. Subsequently, effects of different factors, including the jamming pressure, the roughening process of fibers, the ratio of overlapping area of fibers, and the strain-stiffening of DEs, on the output force performance of the DECA are considered, respectively. Afterwards, the grasping and gripping performance is explored by exhibiting a comparison of the gripper with and without stiffness-tunable effect. Finally, the output gripping force of the stiffness-tunable gripper under different jamming pressures and object sizes is investigated. The maximum size limitation of the gripped object and the output force of the robotic gripper (induced by stiffness tunability) are found to be 12 cm and 5 N, respectively.