Research On Soft Exoskeleton Fingers Of Extensible Joints And Preparation

With the development of driving technology and plastic materials,it becomes possible to build soft robots.Compared with traditional rigid rehabilitation robots,soft rehabilitation robots have irreplaceable advantages: the soft rehabilitation robot can achieve continuous deformation,theoretically unlimited The degree of freedom can easily accomplish tasks that are difficult or even impossible for rigid robots and have better compatibility with organisms.The soft rehabilitation robot has low rigidity and can follow the patient's malformation while driving the patient to perform rehabilitation exercises.The motion trajectory moves and provides a force in the direction of a predetermined motion trajectory,rather than forcing the patient to follow a predetermined motion trajectory.Therefore,the robot will become the best choice for rehabilitation equipment.Firstly,this paper analyzes the motion law of human finger joints,and then extracts the kinematic model of the hand exoskeleton hand joints.Based on this,a new type of soft expandable joint that can be attached to the outside of the finger and assists the movement of the finger joint is designed.The joint is based on the FEAs.The joint body adopts an optimized bellows structure to ensure large extensibility of the exoskeleton hand joints.While ensuring effective extension,the drive capability of the extreme position is improved,and at the same time,the folds are raised The rigid skeleton makes the entire joint become a rigid-flexible coupling body,which effectively weakens the balloon effect of the aerodynamic flexible joint and improves the stiffness of the joint.And using ABAQUS finite element analysis software to optimize the analysis of the joint structure,movement angle and driving ability.Secondly,based on the above analysis,a three-finger soft exoskeleton hand was designed.Combined with the structure of the joint,a combined mold under rigid and soft mixing was designed and its preparation method was designed.On this basis,a pneumatic circuit control system for three-finger soft exoskeleton hand was built to verify the movement ability of soft exoskeleton hand.Kinematics analysis was performed on the soft exoskeleton joints and fingers.Finally,the experimental verification of the extensible joint and soft exoskeletal hand was performed.The verification platform was constructed including air compressor,solenoid valve,and pneumatic circuit system.The control circuit was designed with STM32 as the control core.The solenoid valve was controlled by the relay and the pressure transmitter was used to measure the pressure.For the joints in the presence or absence of resistance,the range of motion test,the joint load test,the ability of the soft exoskeletal hand to hold the test,and the joint load capacity ratio test were examined.