Visual Modeling And Dynamic Analysis Software Development Of Parallel Shaft Gear System Based On Graph Theory

Gear transmission system is widely used in various mechanical equipment because of its high transmission efficiency,high precision,large bearing capacity and simple structure.Due to the diversity of its structure and the variability of its connection mode,it is necessary to conduct specific analysis for different types,which greatly increases the difficulty of modeling and analysis of gear transmission system.Therefore,a general kinematics analysis and dynamics modeling method of parallel shaft gear transmission system is proposed,which has important guiding significance for improving the analysis efficiency of gear transmission system and low vibration and noise design.In this thesis,the parallel shaft gear system was taken as the research object.Based on the idea of graph theory,a general method for kinematics and dynamics analysis of parallel shaft gear system applicable to different configurations was proposed.The visualization and dynamics analysis software of parallel shaft gear system was developed to study the static and dynamic characteristics of the system.This thesis carries out research in the following aspects:(1)Based on graph theory,a unified graph symbol representation method of parallel shaft gear system was proposed,and its correlation matrix mathematical model was established.The graphical symbol representation method combines the functional discrete method and applies the hierarchical theory.Compared with the previous graph theory model,the graphic symbol representation method can better reflect the connection relation,relative position and differentiation degree of the internal components of the shafting in the parallel shaft gear system.The forming process of the transmission correlation matrix M of parallel shaft gear system was introduced in detail and the subsequent kinematics and dynamics analyses were transformed into matrix operations.(2)Based on the correlation matrix M,combined with the basic motion unit of parallel shaft gear system and the depth-first transmission path search method,a general method for kinematics and dynamics modeling analysis of parallel shaft gear system was proposed.This method takes into account the relationship between the components in the basic moving unit and the series and parallel relationship between the basic moving units,and also takes into account the calculation method of gear torque in the multi-load gear train,so that the established speed and torque equations and the dynamics model are suitable for the transmission system of different configurations such as multistage transmission,planetary gear train and branch gear train.(3)Completed the construction of two-dimensional/three-dimensional structural models of each transmission unit in the parallel shaft gear system.Based on.NET platform GDI+technology,a two-dimensional interactive structure model of ladder axis was constructed.Based on Anycad 3D solid modeling technology,the 3D structure models of step shaft,cylindrical gear and bearing of transmission unit were constructed by decomposing the structure of each 3D model.(4)Based on the functional requirements of the software,the overall framework and module composition of the software were determined,and the design of the modeling module and calculation program was realized.By establishing input and output interfaces between each module,the visualization and simulation calculation functions of parallel shaft gear system were completed.Finally,by comparing the software simulation with the test,the relative error of simulation value and test value of dynamic transmission error acceleration of gear pair under specific working conditions is-5.37%,which verified the reliability of the software simulation algorithm.(5)This software was used to calculate the planetary gear train and the multi-load threebranch gear train,and the static characteristics and dynamic response characteristics were analyzed.The results show that,for the parallel shaft gear system with asymmetric structure,the load distribution among the branches will be uneven,which leads to the great difference in the gear torque,transmission error and meshing stiffness,which accords with the vibration transmission law of the system.The concrete application of graph theory was discussed,and the universality and feasibility of this software simulation algorithm were verified.