Design Of Dual-Arm Transfer Robot And Experimental Study On Patient Transfer

With the acceleration of the process of population aging around the world,and the increasing demand for long-term care of nursing subjects,the shortage of medical staff at home and abroad has become increasingly prominent.At present,most medical institutions rely on medical staff or patients' family members to carry out transfer tasks by lifting,holding,and supporting.This traditional transfer method is cumbersome,tedious,and inefficient.Using robots to assist medical personnel in completing transfer tasks will greatly reduce the work intensity of medical staff and help improve the quality of nursing care and the efficiency of medical institutions.Therefore,this paper conducts frontier exploration on transfer robots that can realize human-robot cooperative transfer.Based on the large load characteristics of the palletizing robot and the stroke amplification function,the robot unit arm adopts a parallel four-bar linkage structure,which can meet the working requirements of the objects whose weight is larger to be moved on the sickbed,wheelchair,and ground.Based on the configuration and load requirements of the robot arm,Adams is used for parameterized optimization analysis to determine the reasonable structure parameters of the robot arm.Then the threedimensional model of the transfer robot is created.According to the main size parameters of the transfer robot,a mathematical model of the articulated manipulator is established.Using vector method to carry out kinematics analysis,and the mapping relationship between the manipulator's operating space and joint space is established to check the robot workspace.The nursing objects and transfer circumstances are categorized according to group characteristics and supporting methods,thereby determining the working methods and work contents of the transfer robots.In order to improve the efficiency of the transfer work,according to the combination of different nursing objects and transfer circumstances,the transfer process is planned to establish a standardized transfer mode.According to the changes of human posture in the transfer process,the human body is divided into segments,and a four-stage static man-machine model is established to analyze the relationship between the contact force and the human joint torque in the process of patient transfer.The comfort evaluation in the process of patient transfer is divided into two aspects: psychological and physiological.The method of expanding the psychological comfort zone is analyzed.The softness distribution model and the musculoskeletal model are established to analyze the physiological comfort.In order to obtain safe,reliable and efficient holding techniques and to better plan the movement trajectory of arms of the transfer robot,the human lifting experiment under single-sided supporting scene of patient transfer is performed to analyze the shoulder joint trajectory,knee joint trajectory and the change of back inclination angle,hip joint angle,knee joint angle in the sagittal plane of subjects.The joint trajectories with higher comfort evaluation are selected as control reference of arms of transfer robot,and the reference ranges of the joint angles under stable holding posture are given.