Design And Analysis Of Harmonic Drive3C Tooth Profile Based On Centrode

Supported by the National Natural Science Foundation of China (No.50975038)---"Study on Elastic Kinematic Geometry and Tooth Profile Design Method of Harmonic Drive", this paper presented a new tooth profile based on our research group’s study of the harmonic drive, And completed the kinematics simulation and profile modification after establishing the parameter Design Guideline and the kinematic model. The nodal displacements of neutral-layer under load condition are extracted and fitted by fourier function after dynamic simulation model is completed by using Abaqus, therefore, the centrode under load condition is obtained. On that basis, optimization and property evaluation of3C profile are completed.First of all, the kinematic model of harmonic drive is established based on the deformation function of the wave generator on no-load condition and the centrode conjugation theory. A new kind of tooth profile and the design guideline for structure parameters of the flexspline cup is developed. The tooth profile of circular spline is given before the tooth profile of flexible spline obtained through solving conjugate equation and transformating coordinates based on centrode conjugation theory. MATLAB GUI interface is prepared to input the structure parameters of flexspline cup and tooth shape parameters conveniently. Kinematics simulation of conjugate process is simulated and the tooth profile parameters are confirmed and improved by interference check. And the solution of the harmonic drive conjugate tooth profile with visual output are realized, then it is convenient for the modification initial parameters and man-machine interaction.Secondly, by using abaqus, finite model of harmonic gear drive in form of cup is developed. At the same time, entity simulation on assembly process of harmonic drive is established utilizing general module Abaqus/Standard, and the nodal displacements on neutral-layer under no load are picked up, and then compared with the theoretical deformation. The work process of harmonic gear drive under load condition is simulated by explicit analysis module--Abaqus/Explicit. The deformation function under load is picked up and fitted by Fourier function in the cftool toolbox of Matlab and the distorted law of centrode is obtained. Based on the above, the flexspline tooth profile is modified and the property of the optimized profile is studied. A new tooth profile---3C tooth profile with superior conjugate property consisting of two arc and a cyloid is worked out and kinematically simulated by Matlab in this paper. The finite element simulation of harmonic drive with3C tooth profile is done by Abaqus. The result shows that the tooth profile’s centrode and the deformation function is stable. That is the evidence of3C tooth profile’s superiority.The research method and conclusions on The design principle of cup structural parameters and the evaluation of meshing property for harmonic drive in this paper are of theoretical significance and practical value to the study on harmonic drive’s fatigue life and meshing property.