Design And Experiment Of Hand Rehabilitation Device Based On SMA

With the increasing number of stroke patients,the rehabilitation training of patients has gradually become a hotspot of modern medical and industrial research.The application of mechanical structure in daily rehabilitation training can not only alleviate the shortage of doctors in rehabilitation training to a certain extent,but also improve the efficiency and effect of rehabilitation.Since most of the survivors of cerebral apoplexy will leave behind hand dysfunction,the research on hand rehabilitation training device has important research significance and demand background.In this paper,a new type of under-actuated hand rehabilitation device is designed based on shape memory alloy(SMA)to realize miniaturization and safety of the existing hand rehabilitation device,which is large in size and inconvenient to carry.The main research work of this paper is:1.Design scheme of hand rehabilitation device based on SMA.Under the guidance of rehabilitation physicians,combined with the pathological characteristics of hemiplegia and rehabilitation theory,the design requirements of hand rehabilitation device were put forward from the medical perspective,and the design scheme of hand rehabilitation device based on SMA was determined.The scheme adopts underactuated mode and has the characteristics of small size and easy to carry.2.Design of hand rehabilitation device.Based on the modular design concept,the hand rehabilitation training device is divided into several modules,and each module is analyzed and designed in detail.On this basis,combining with the relevant model of shape memory alloy,the rationality and feasibility of the design are verified through the comparative analysis with the experimental results.3.Simulation analysis of hand rehabilitation device.The statics analysis and the dynamic analysis software RecurDyn were used to verify the relationship between the output force of each knuckle of fingers and tendon tension of the hand rehabilitation device when it assisted fingers to grasp objects.Based on the RecurDyn software,we analyzed the rotation relationship of finger knuckles under different voltages,and the relationship between the Angle,angular velocity,angular acceleration of each knuckle of the index finger and the power on time for the appropriate voltage.The effect of shape memory alloy spring on the surrounding environment was analyzed by Flotherm.4.Experimental study on hand rehabilitation device.Based on the comparison and analysis of fuzzy control strategy and PID control strategy,the control scheme of hand rehabilitation device was determined.The prototype of the device is printed by 3D printing technology,and the experiments of flexion and extension and grasping are respectively carried out.The results show that the hand rehabilitation device can assist the fingers in relevant rehabilitation movement to a certain extent.