Since its birth in the mid-nineteenth century, air suspension has undergone a century of development. It has undergone a variety of changes, such as "pneumatic SPRING-AIR bag composite suspension semi-active air suspension central charging and deflating suspension (ECAS electrically controlled air suspension system)". It was not until the 1950s that it was used in trucks, buses, cars and railway cars. At present, air suspension is almost used in foreign high-grade buses. The proportion of heavy-duty trucks using air suspension has reached more than 80%, and the application of air suspension in light vehicles is also rising rapidly. Air suspensions are gradually installed in some cars, such as Lincoln in the United States, Benz 300SE and Benz 600 in Germany. The use of air suspension is almost the only choice for some special vehicles, such as instrument vehicles, ambulances, special military vehicles and container transport vehicles with high requirements for earthquake protection. However, China is still in its infancy, and the air suspension system is only used in some luxury buses and a small number of heavy trucks and trailers. During the 1991 Gulf War, the air suspension was made up of fine sand and soft sand because Kuwait was all desert. U.S. Hummers are equipped with a central inflation and deflation system, the air suspension; reducing tire pressure and increasing friction between tires and the ground can prevent tire skidding in the desert, and reducing tire pressure on snowy roads can also increase the friction of tires as in the desert. This is the drawback of hydraulic suspension. Air suspension and hydraulic suspension have their own advantages. Air suspension can reduce tire pressure and prevent slippage. Hydraulic suspension can go up high speed, and can run mountains and cross rivers are their respective advantages.

Generally speaking, the front and rear wheels of the vehicle equipped with air-type adjustable suspension will be equipped with ground-leaving distance sensors. According to the output signal of the ground-leaving distance sensor, the driving computer will judge the height change of the vehicle body, and then control the air compressor and exhaust valve, so that the spring can automatically compress or elongate, thereby reducing or increasing the chassis ground-leaving clearance, so as to increase the stability of the high-speed vehicle body or increase the stability of the chassis. Passability of complex road conditions. In daily regulation, the air suspension will have several states. 1. Keep in good condition. When the vehicle is lifted by the lifter, when it leaves the ground, the air suspension system will close the relevant solenoid valves. At the same time, the computer will remember the height of the vehicle body, so that the vehicle will remain the original height after landing: 2. Normal state, that is, the engine running state. In the course of driving, if the height of the car body changes beyond a certain range, the air suspension system will adjust the height of the car body at intervals: 3. wake-up status. When the air suspension system is awakened by the remote control key, door switch or luggage compartment cover switch, the system will check the body height through the body level sensor. If the body height is lower than the normal height to a certain extent, the gas tank will provide pressure to raise the body to the normal height. At the same time, air suspension can adjust the hardness and softness of shock absorber, including soft, normal and hard three states (also marked as comfortable, ordinary, sports three modes), the driver can control through the control button in the car.

Of course, compared with the traditional suspension, because the structure of air-type adjustable suspension is more complex, the probability and frequency of failure will be higher than that of coil spring suspension system. Using air as the power source to adjust the chassis height, the sealing of the relevant components is also a problem. In addition, if the chassis height is frequently adjusted, it may cause local overheating of the air pump system, which will greatly increase. Shorten the service life of the air pump. Of course, with the continuous improvement of technical level, many problems have been well solved, at the same time, more and more widely used models.