Design, analysis and experiment of finger soft actuator with nested structure for rehabilitation training

Abstract

Compared with the rigid hand rehabilitation robot, the soft hand rehabilitation robot has the advantages of good flexibility, which is of great significance to its research. In order to make the soft hand rehabilitation robot have the advantages of high stiffness and simple manufacturing process, a nested structure is proposed for finger soft actuator in this paper. The nested structure consists of outer restraint structure and inner core structure. The inner core structure can realize deformation under the action of air pressure. The outer restraint structure can improve bending efficiency by restraining deformation in non-functional direction of inner core structure. On this basis, the processing technology of nested structure is designed, and the effect of structural parameters on performance is analyzed. In order to illustrate the advantages of nested structure, the performance of nested structure and fiber-constrained structure is compared by simulation, which includes bending angle, gripping force and expansion amount (by measuring the deformation of the cross section). The simulation results show the advantages of the nested structure. A prototype of the soft hand rehabilitation robot is developed with nested structure as finger soft actuator, and the experimental results prove the feasibility of design. The results of this study provide a reference for the structure design of soft hand rehabilitation robot.