Kinematics And Mechanics Research On The Lower Extremity Exoskeleton Robot Human-machine System

A kind of wearable lower extremity exoskeleton robot is researched in this paper. Lower extremity exoskeleton robot is a kind of typically man-machine integrated system with some biped walking robots’ characters. It could help people to accomplish the travel, loading and other tasks that can not be completed by people’s own capacity lonely. As Lower extremity exoskeleton robot can be worn on the human body as a mechanical device, study on the force and the mutual position relations between human body and the mechanism is so important in the design, which is the focus of this research.At first this paper analysis the model and the motion mechanism of human lower limb skeleton, and gait movement feature of the lower limb bones with normal walking. The model of lower limb bone, joint trajectory characteristics is established. By focuses on the joint position and configuration of exoskeleton mechanism, as well as the joint design scheme, the three-dimensional model of lower extremity exoskeleton robot is established.Then a mathematical model of Human-machine constraints when the human body wear the lower extremity exoskeleton robot mechanism is established by using D-H parameter method. Analysis and optimization about Human-machine constraints has been carried through by this model. A method of judging whether the constraint is reasonable is presented based on the man-machine kinematics analysis.Finally, the man-machine system of the human body and lower extremity exoskeleton robot is simulation with the ADAMS software. The error curve of driving joints and following joint in different constrained conditions has been obtained by motion simulation, the influence of following effect in different position of constraints has been analyzed. The simulation results of the system have drawn some conclusions, which provide effective reference for the design of the exoskeleton mechanism.Through the above analysis and simulation, a more comprehensive analysis of the impact of constraints on man-machine system has been achieved and the optimization method of man-machine constrained been put forward, the research lays the foundation for the following.