Research On Two-stage Tooth Profile Modification Of Robot Precision Cycloidal-pin-annulus Reducer For Robot

As the core part of industrial robot,precision cycloid pin gear reducer is composed of involute planetary gear and cycloid pin gear transmission.The transmission accuracy of precision reducer is determined by two parts of transmission mechanism.In order to improve the dynamic transmission accuracy of precision reducer,the two-stage tooth profile of precision reducer is taken as the research object,and the two-stage tooth profile is considered as the research method to optimize the two-stage tooth profile,so as to achieve the use requirements of high precision and high load of precision reducer.Based on the existing research,the following works are carried out: the working principle of precision reducer is described in detail,three main involute profile modification parameters are elaborated by analyzing the involute profile modification principle,the involute profile equation with modification parameters is derived,and the maximum modification of involute profile is calculated according to the modification estimation formula,The parametric model of involute gear including the modification parameters of tooth profile is established by 3D modeling software;By explaining the cycloid forming principle of external rolling method and internal rolling method,the standard cycloid equation is established.Based on the defects of standard cycloid gear in precision reducer,the necessity of cycloid tooth profile modification is explained.The cycloid tooth profile parameter equation including five traditional modification methods is established,and the modification method of "negative equidistance + positive displacement" is determined,In the MATLAB optimization toolbox,an optimization model is established to calculate the amount of cycloid tooth profile modification.After the optimization model is determined,the cycloid gear with tooth profile modification is parameterized;After the whole model of precision reducer is assembled,the virtual prototype of precision reducer is established based on ADAMS platform.The influence of two-stage tooth profile modification on transmission accuracy of precision reducer is studied by virtual experiment.The results show that compared with the virtual prototype of precision reducer without considering tooth profile modification,The results show that the transmission accuracy of the whole machine is increased by 20.5% and 23.4%respectively,and the running stability is increased by 41.3% and 53% respectively;After determining the two-stage tooth profile modification method and modification amount of precision reducer,the influence of two-stage tooth profile modification on gear transient contact performance is studied based on ANSYS Workbench platform.The results show that when the tooth profile modification is considered between involute gear and cycloid pin gear,the stress and strain of involute tooth profile after modification are reduced by 10.4% and19.4% respectively,After cycloidal profile modification,the stress and strain are reduced by31.7% and 29.0% respectively.