Vibration control methods can be classified into three main types: elimination of vibration source, isolation and reduction of response. Elimination is to remove or weaken the vibration source. Isolation is to reduce the impact of vibration on equipment by adding vibration isolation elements between vibration sources and equipment, so as to control the vibration of machines and instruments, and limit the vibration intensity to the allowable range. To reduce the response, a subsystem is added to the controlled object, so that the vibration force is generated to reduce the response of the controlled object to the vibration source. Isolation vibration is the most widely used method in mechanical systems.
According to the direction of vibration transmission, there are two types: active vibration isolation and passive vibration isolation.
1) Active vibration isolation
Active vibration isolation is to isolate the source of vibration. If the machine produces obvious vibration or shock during normal operation, it can be isolated from the support body with a vibration isolator, so as to protect other machines or people from the impact of vibration. For example, the vibration generated by an aircraft engine can have a significant impact on the operation of precision equipment on board, reducing the impact by installing vibration isolators on the base of the engine. The vibration isolation of general power machines or rotary machines is active vibration isolation.
2) Passive vibration isolation
Passive isolation is to isolate the vibration caused by basic movement. Some sensitive equipment often needs to work in the environment of intense impact or vibration, which can be installed on the isolation device to protect it from the influence of surrounding environment. For example, precision instruments installed on ships are vulnerable to strong vibration and shock during operation at sea. Therefore, these instruments are often installed on vibration isolators to protect them from damage. Although the concept of active vibration isolation and passive vibration isolation is different, the implementation method is the same. The function of the isolator is to reduce the impact of vibration from the device to the foundation, or to reduce the size of motion from the vibration base to the device.