Finite Element Analysis And Structural Optimization Of Harmonic Reducer

Harmonic reducer is a core component that can realize precision transmission.Because the flexspline and bearing of harmonic reducer are thin-walled parts and bear periodic elastic deformation and alternating load during transmission,improving fatigue life and transmission performance has become the focus and difficulty of its research.In this paper,the harmonic reducer is studied from the aspects of stress and deformation,torsional stiffness,structural optimization and dynamic characteristics,and its specific research contents include:Firstly,the structure and transmission principle of harmonic reducer are introduced;The deformation shape of flexspline under wave generator is analyzed;The stress theory and strength checking method of flexspline are introduced.It laid the foundation for the follow-up research.Secondly,the three-dimensional model of harmonic reducer is established by UG software,and the finite element analysis model is established by importing it into ANSYS software;The deformation law and stress distribution of harmonic reducer assembly are analyzed,and the influence of load on harmonic reducer is studied;The influence of wave generator assembly position on flexspline stress,bearing stress and torsional stiffness is analyzed;Through the transient dynamic analysis of harmonic reducer under no load,the results show that the stress and deformation of flexspline change periodically with the rotation of wave generator.Finally,the deformation of flexspline assembly under the action of wave generator is analyzed experimentally by ARAMIS three-dimensional optical deformation and strain measurement and analysis system,and the results of finite element analysis of harmonic reducer are verified.Then,the effects of key structural parameters such as radial deformation,barrel length,barrel wall thickness,transition bevel angle between gear ring and barrel and draft angle on flexspline stress,bearing stress and torsional stiffness are analyzed by single factor analysis method;The structure of harmonic reducer is optimized by orthogonal test,and the stress,torsional stiffness and axial size of harmonic reducer are taken as evaluation indexes,and the combination of structural parameters with better comprehensive performance is obtained by comprehensive scoring method;The fatigue life of flexspline before and after optimization is analyzed by using fatigue analysis software n Code Design Life.The results show that the fatigue life and torsional stiffness are improved,but the axial dimension is slightly increased.Finally,based on the single factor analysis method,the influence of key structural parameters of flexspline on natural frequency is analyzed,and the natural frequency of flexspline before and after optimization is compared and analyzed;Through the computational modal analysis of the circular spline,the natural frequency and vibration mode of the circular spline are obtained;The test modal analysis of flexspline and circular spline is carried out by LMS Test.Lab test system.The results show that the error between the calculated modal analysis results and the experimental modal analysis results is small,and the natural frequency of the flexspline is lower than that of the circular spline and higher than the excitation frequency of the work,so there is no resonance.