Research On The Dynamics Of Hip Joint In Rehabilitation

The lower limb rehabilitation robot is an important subject that be worth researching and development in the field of robots.It can help the people with walking obstacles to realize the daily action of normal people.In a way,the study of hip joint plays an important role in the rehabilitation of lower limbs.Based on the anatomical characteristics of the human hip joint,and in order to complete the movement of three degrees of freedom working with the human thigh together,using the 3-SPS parallel mechanism as a bionic hip joint body is proposed in this paper.In order to make the parallel mechanism have excellent bionic athletic and dynamic performance,some key technologies including the configuration,kinematics analysis and dynamic analysis of the parallel bionic module respectively are deeply researched in this paper.The work of this paper is as follows:The human hip structure characteristics,movement characteristics and its movement space range is analyzed and researched.Mechanism type that the structure and function be consistent with the human hip join is selected.And then,the selection of 3-SPS parallel mechanism as a bionic hip prototype mechanism is determined.The kinematic model of the hip joint mechanism which using 3-SPS symmetrical parallel mechanism as the core mechanism is established,also the spatial position of the mechanism is described.The displacement inverse/positive equation of the mechanism,velocity inverse /positive equation and Jacobian matrix are established.In the parallel mechanism,positive kinematics has multi-solution,and is more complicated generally,however,the inverse kinematics solution is unique and relatively simple.The kinetics analysis of 3-SPS parallel mechanism is done by using the Lagrangian method.Based on the kinematics analysis,the kinematic parameters of the centroid of the parts are analyzed,and the dynamic equation of the parallel mechanism is established by considering the whole potential energy and kinetic energy of the 3-SPS parallel mechanism.The three-dimensional model of the mechanism was established in computer by Pro/E software,and the computer simulation analysis of kinematics and dynamics were realized by ADAMS software,The angle change curve of the parallel machine platform,the displacement of the drive bar,velocity and acceleration curve of the driving rod of the parallel mechanism are obtained by the computer simulation analysis.On the basis of correctness of the mechanism motion is verified,the external load is applied to the dynamic platform,then the dynamic simulation of the mechanism is carried out.