Design and Experimental Evaluation of a Bionic Two-joint Soft-actuator

Soft Pneumatic-Network Actuators have been widely used in making soft grippers in the field of soft robotics due to the advantage of flexible bending deformation. In order to improve grasping stability, a bionic two-joint soft actuator inspired by a human finger is proposed in this paper. Firstly, the structure of the soft actuator is designed, and the bending deformation of the actuator is studied through inflation simulation. Next, a sample of the soft actuator is made by 3D printing and molding methods, and the bending angle and tip force of the actuator are investigated through a series of experiments. Finally, two types of soft grippers are fabricated, and the grippers are applied to grasp objects of various shapes. The results show that the soft actuator can bend mimicking a human finger, and the soft grippers can lift or grasp objects similar to the function of a human hand, which demonstrates the bionic applicability of the proposed soft actuator.