Coupled Simulation Of Human Lower Limbs And Rehabilitation Robot Based On OpenSim

With the current situation of decline or loss of human lower limb motor skills caused by illness and aging as well as digital simulation and optimization of control algorithms for new lower limbs rehabilitation robot,the paper studies on kinematics and dynamics of musculoskeletal models of lower limbs and exoskeleton lower limb rehabilitation robot to explore solutions of positive coupling simulation between them,aiming to gain optimized parameters of control algorithm and gain better restore of muscle energy through adaptive gait training.The main work of this paper is summarized as follows:1.Analysis of key technologies on modeling and simulation in OpenSim.The human motion simulation software OpenSim developed by more than a dozen scholars such as Frank Anderson from Stanford University of the United States contains a large number of human body model and the gait data and it can achieve positive dynamics simulation.Processes to achieve positive dynamics simulation and Computed Muscle Control Algorithm(CMC)which is used to gain positive solution as well as muscle-tendon mechanics model was introduced.Kinematics and dynamics simulation on human model was conducted with input of gait data,gaining several physiology curve.2.Modeling and simulation of lower limbs rehabilitation robot.Currently the technology of lower limb rehabilitation robot Lokomat from Hocoma company is relatively mature and widely applied.Lokomat was redesigned and built by three-dimensional modeling software SolidWorks considering size parameters of Lokomat on Hocoma’s official website as well as corresponding size parameters of selecter human model in OpenSim.Kinematics and dynamics simulation of Lokomat was constructed in multibody dynamics simulation software RecurDyn,obtaining consistent curve with the results of simulation on human model and laying foundation for coupling simulation of lower limbs and rehabilitation robot.3.Coupling simulation and analysis of lower limb and rehabilitation robot.Human lower limbs combined with rehabilitation robot was built based on technology of XML format file.Coupling simulation between lower limb and rehabilitation robot was achieved through co-simulation between OpenSim and Matlab by writing code in Matlab,gaining more satisfactory results.This verifies the rationality and correctness of design of Lokomat and effect that motor skills can be recovered by scientific gait training can be achieved.Control algorithm models on Bushing force which plays role in simulation were introduced to facilitate post-work.