In general, mechanical system is composed of power system, transmission system and executive system, in which the power system provides the initial motion and force required by mechanical system, but the power system provides simple form of motion and force, which can not meet the requirements of different forms of executive system, which requires the transmission system to change the force and motion output by the power system, and the transmission system The working performance of the system has a great influence on the mechanical system. In the current industrial background, driven by the industry specialization, the structure and form of power system and executive system tend to be consistent. The change of the performance of the whole mechanical system is realized by changing the transmission system. Now the requirements of mechanical system are not only to be able to complete its functions, but also to be efficient, high-speed and precise, which has higher requirements for the performance of mechanical system, and the improvement of the performance of transmission system can meet the requirements of mechanical system for service life, efficiency, vibration and noise.

Gear system is the most widely used in the transmission system, especially in various high-performance mechanical systems, its performance directly affects the working efficiency and stability of the mechanical system, so the research on gear system is the key to improve the performance of the mechanical system. With the development of mechanical system towards high performance, the design of gear system should meet the requirements of high efficiency, high reliability, high stability, high speed and heavy load, lightweight, low vibration, low noise and short design cycle. In order to meet these requirements, it is necessary to study the transmission accuracy and service life of gear system.

The transmission accuracy of the gear system is based on the gear meshing principle and through the research of the tooth shape. For example, the vibration and noise of the transmission system can be reduced by the tooth profile and the tooth direction modification, and the dynamic characteristics of the gear can also be studied by the system dynamics. The tooth contact of gear system directly affects the bearing capacity and transmission stability of the gear. TCA (tool contact analysis) technology is to simulate the shape and position of the tooth contact spots without considering the loading deformation and error. With this technology, the contact situation of the tooth surface can be analyzed intuitively and effectively. The finite element method can be used to study the meshing of gear system, reduce the real working condition of gear system, and consider the influence of elasticity, error, thermal deformation and other conditions on the meshing of gear system. The finite element method is a powerful tool to study the meshing of gear system.

The automobile transmission is an important part of the automobile transmission system, and the gear system directly affects the performance of the transmission. At present, with the continuous improvement of the performance requirements of the automobile, such as ride comfort, driving stability and power performance, the gear system requires rapid design and good dynamic performance. With the rapid development of automobile and the continuous improvement of driving performance requirements, the design method of gear is also put forward higher challenges. The new design method of gear should meet the development requirements of automobile industry. The development of computer technology provides the possibility for CAD, and the CAD design of gear improves its working efficiency. However, the existing CAD design of gear is not a real design, which can not meet the requirements of current gear design methods. In this paper, the parameter optimization design of gear is studied. In essence, the design of gear can be completed on the computer, including the three-dimensional modeling design and performance analysis of gear. In this way, the dynamic design of gear can be completed, and the high-performance gear can be designed in the shortest possible time.

Now, a lot of 3D software can complete the 3D modeling of standard gears, but with the improvement of gear processing technology, different parameters of gears can be processed arbitrarily. Therefore, the 3D modeling of gears needs to consider more parameters as much as possible on the basis of the tooth surface equation, so as to prepare for the optimal design of gears and complete the corresponding performance analysis. The parameter optimization design method of gear is to complete the performance analysis of gear by using relevant software when completing the parametric modeling of gear, so as to complete the design of gear on computer. In the current industry background, the CAD design and CAE analysis of gears are the only way for the development of gear design, and the CAE analysis of gears can realize the research of its performance in all aspects. Under the condition of ensuring the performance of gears, the design cycle is shortened and the working efficiency is improved.