The linear damping force is proportional to the velocity, but in the opposite direction, which is expressed as F=-cv, and c is the viscous damping coefficient, and its value must be determined by vibration test. In physics and engineering, the mechanical model of damping is generally a force that is proportional to the vibration speed and opposite to the vibration speed. This model is called viscous damping model, and this force is damping force. Damping refers to the characteristic that the vibration amplitude of any vibration system decreases gradually due to external effects or inherent reasons of the system itself, and is a quantitative representation of this characteristic.