Design and Kinematic Characteristics of Rigid-flexible Coupling Bionic Finger

Abstract

The bionic hand can achieve various complex movements, which is widely used in the field of industry and medical treatment. While the existing rigid bionic hand has limitations of heave weight and poor flexibility, the soft hand with low control accuracy is difficult to achieve powerful griping. Therefore, based on the structure of human hand, this study develops a rigid-flexible coupling bionic finger. While the rigid bones are fabricated by 3D printing technology, the intrinsic muscles and extrinsic muscles respectively use the thin-McKibben pneumatic artificial muscles of diameters 1. 3 mm and 2 mm developed by Prof. Koichi Suzumori in Tokyo Institute of Technology. A kinematic model of bionic finger is established by using BP artificial neural network, and the coupling relationship between the joint motion and muscle is analyzed. The prediction accuracy of the model is evaluated by the experiments. Comparing with results of anatomy, it can be confirmed that the developed hand has great similar driving principle and kinematic characteristics with human hand.