Structural Design And Simulation Analysis Of Lower Extremity Exoskeleton Robot

People's perception about exoskeleton originates from explorations of insects and crustaceans, since exoskeleton can provide protection and support for these animals. Based on this inspiration, human beings begin their researches on exoskeleton robot, which is a compound system combining machinery, bionics, management, ergonomics and some other research fields. Human beings can wear it on the body to get support and protection as well as to assist them in completing a series of complex movements. In recent years, the practical value of exoskeleton robot has been attracting increasing attention both at home and abroad. Therefore, this paper mainly centers on the fundamental researches of exoskeleton robot' structure, which includes the following parts:By comparing the status quo of research at home and abroad, learning the knowledge of human anatomy, and giving full consideration to the compatibility of exoskeleton robot and human body, this paper rearranges the degree of flexibility of human bodies' joint of lower extremity. It also conducted designs as to the main joints of exoskeleton's lower extremity, including hip joint, knee joint and ankle joint. Based on the above-mentioned points, this paper finishes a structural design on the whole machine of exoskeleton robots' lower extremity.Taking advantage of the D-H method to build a kinetic model for the exoskeleton robot system, this paper describes the relationship between the joint variable of exoskeleton's lower extremity and its position. In the following, this paper conducts kinetic analysis as to different phases of the periodicity of human gait by using the Lagrange method and hence, obtains the joint torque of different stages of walking. Finally, this paper builds kinetic model of exoskeleton robots and looks for answers.According to the joint angle data provided by CGA database, this paper utilizes ADAMS to conduct kinetic simulation on virtual prototype, including the motion stimulation of human body model and the combined stimulation of exoskeleton robot and human body model. By comparing the results of stimulation, this paper proves that the movements of exoskeleton robot can perfectly match those of human body's lower extremity and can also save some energy for human body during the process of movement. Therefore, this paper further demonstrates that the design of the exoskeleton robot' movements is reasonable. Besides, this paper also conducts stimulation on exoskeleton robots' going upstairs, which further verifies the reasonability of this structure.Based on the Finite Element Theory, this paper takes advantage of the ANSYS workbench software to conduct finite element analysis to the mechanical structure of exoskeleton robot. By conducting static structure analysis as to the exoskeleton structure during different times of the gait cycle, the paper verifies that the design of the mechanical structure can meet the requirements of both strength and stiffness. The inherent frequency and modal vibration are obtained by conducting finite modal analysis of exoskeleton robots, which lends theoretical support to the restoration of exoskeleton robot as well as to the further research on exoskeleton robot' system.