Tractors are self-propelled power machines used to tow and drive work machinery to complete various mobile tasks. It can also be used as a fixed work power. It consists of systems or devices such as engine, transmission, walking, steering, hydraulic suspension, power output, electrical instrumentation, driving control and traction. The engine power is transmitted from the transmission system to the drive wheel to make the tractor run. In real life, it is common to use a rubber belt as the medium for power transmission. Agricultural, industrial and special purpose tractors by function and purpose; wheeled, boat-shaped tractors and self-propelled chassis by structural type. Although a tractor is a relatively complex machine, its type and size vary, but they are all composed of three parts: engine, chassis, and electrical equipment, each of which is indispensable. It is a device that generates power for a tractor, and its function is to convert the thermal energy of fuel into mechanical energy to output power outward. Most of the agricultural tractors produced in China use diesel engines. It is a device that transmits power to a tractor. Its function is to transfer the power of the engine to the drive wheel and the working device to make the tractor run, and complete the moving or stationary role. This role is achieved through the mutual cooperation and coordination of the transmission system, the walking system, the steering system, the braking system and the working device, which in turn form the skeleton and body of the tractor. Therefore, we collectively refer to the above four major systems and one major device as a chassis. That is, in the tractor as a whole, all systems and devices other than the engine and electrical equipment, are collectively referred to as the tractor chassis.