Mechanical transmission is widely used in mechanical engineering, mainly referring to the transmission of power and motion through mechanical means. There are two types of friction transmission: one is the transmission of power through friction between components, and the other is the transmission of power or motion through meshing between active and driven components or through the use of middleware. There are various forms of mechanical transmission, which can be mainly divided into two categories: ① friction transmission that relies on the friction between components to transmit power and motion, including belt transmission, rope transmission, and friction wheel transmission. Friction transmission is easy to achieve stepless speed change and can mostly adapt to transmission situations with large shaft spacing. Overload slipping can also play a buffering and protective role in the transmission device. However, this type of transmission is generally not suitable for high-power situations and cannot guarantee accurate transmission ratios Meshing transmission that relies on the meshing of active and driven components or the transmission of power or motion through the meshing of middleware, including gear transmission, chain transmission, spiral transmission, and harmonic transmission. Meshing transmission can be used in high-power applications with accurate transmission ratios, but generally requires high manufacturing and installation accuracy.