Optimization of tooth profile modification of cycloid gear considering frictional heat conditions
WEI Chao
JIA Tenglong
KONG Xianglong
LIU Hao
LI Chaoyang
Abstract：[Objective]The contact stress and frictional heat generation between the cycloidal gear and pin teeth critically influence the transmission performance and service life.Current research on profile modification optimization mostly focuses on a single objective,lacking comprehensive consideration of thermo-mechanical coupling effects.To address this issue,a multi-objective optimization method for cycloidal gear tooth profile modification was proposed considering frictional heat conditions,aiming to simultaneously reduce the maximum contact stress and frictional heat flux density on the tooth surface,and to improve the temperature distribution.[Methods]Firstly,a theoretical load contact analysis model was established according to the meshing characteristics of cycloidal planetary transmission,providing a mechanical calculation foundation for subsequent optimization.Secondly,the tooth surface was discretized and the frictional heat flux density calculation was introduced,and an optimization function was constructed with the objectives of minimizing the maximum contact stress and the sum of heat flux density.Then,a genetic algorithm program was coded using Matlab software,the range of modification parameters and constraint conditions were set,and a multi-objective optimization model for tooth profile modification was established,with feasibility judgment and penalty mechanisms added to address iteration non-convergence and abnormal results.Finally,the temperature fields of the tooth surface before and after optimization were compared through finite element simulation,and the optimization effect was evaluated in combination with theoretical calculation of meshing efficiency.[Results]The results show that after multi-objective optimization,the maximum contact stress on the tooth surface is slightly reduced,and the total heat flux density on the tooth surface is significantly decreased.The simulation results show that the maximum tooth surface temperature is reduced by 5.346℃and the area of temperature concentration is notably diminished.Meanwhile,the meshing power loss is decreased,and the meshing efficiency is improved by 1.5 percentage points.
Keywords：Cycloid gearGenetic algorithmTooth profile modificationMulti-objective optimization
Publication Date：2026-08-15
Online Publishing Date：2026-09-12(First online date of this platform, not the publication date of the document)
Pages：8( 21-28 )