Design And Finite Element Analysis Of Harmonic Drive With Short Flexspline

With the rapid development of the current robot industry,The demand for robot harmonic reducers is growing.In particular,the short flexspline harmonic reducer is widely used in the robot market due to its small axial dimension.However,The level of research and development and the overall design and manufacturing of short flexspline harmonic reducer in China are relatively backward which are unable to meet the huge domestic robot market demands.Therefore,combining with the development project of school-enterprise cooperation which is named as " research on theory and application technology of precision Reducer " and based on the method of finite element,the space tooth profile of the short flexspline was designed and the two key parts of the harmonic reducer,the flexspline and the flexible bearing,were analyzed emphatically as well as the finite element simulation was carried out in this thesis.What's worth mentioning,the research results of this thesis can provide important technical support for the research and development of the harmonic reducer.The main research contents of this thesis are summarized as following:First of all,the main section of the design of the flexspline space tooth profile was determined through analyzing theoretically the contact form between the flexspline and the flexible bearing,the conjugate profile was solved by using the improved kinematic method and the space radial deformation of the flexspline was also obtained based on the finite element simulation.On this basis,the method of changing the wall thickness of flexspline gearring was used to design space tooth profile,the meshing characteristics of harmonic drive was analyzed by matlab software programming.the tooth profile parameter of the flexspline was optimized via orthogonal experiment and finite element simulation.Secondly,some other analyses were also implemented in this thesis:The finite element analysis of the flexspline was made under the load condition with the ANSYS Workbench software;the deformation force of the flexspline was calculated and the modal analysis was carried out in the prestressed state.The stability of the flexspline was checked by adopting the linear buckling analysis method.Not only the kinematics relation and force of the flexiblebearing were analyzed theoretically,but also the stress deformation distribution of the flexible bearing under the condition of load were gotten via the finite element simulation.Furthermore,according to the theory of heat transfer and the existing classic formula,The frictional heat flux and convective heat transfer coefficient of the flexspline and flexible bearing are calculated while the finite element model of the temperature field of the flexspline and the flexible bearing was established and the simulation analysis was carried out though the finite element method.The effect of temperature field on the stress and deformation of harmonic reducer was analyzed by using sequential coupling method.Finally,as shown in this thesis,on the one hand,using the modification method of that circular arc,three cubic Beckinsale curve and B spline curve were adopted at the contact place of the flexspline and the wave generator was proposed.After that,the stress and deformation of the flexspline was analyzed after modification by finite element simulation.On the other hand,The process route of the flexspline manufacturing was prepared in detail,the prototype of harmonic reducer is processed and assembled,and the test device for the transmission precision,transmission efficiency and two degree of freedom mechanical arm of harmonic reducer was designed.