The upper end of a shock absorber is connected to the vehicle body or frame, and the lower end is connected to the axle. When a car travels on uneven roads, the body vibrates. The shock absorber quickly dampens these vibrations, using the resistance of its fluid flow to dissipate the energy of the vibrations.
Most modern cars use telescopic shock absorbers. When the frame and axle move relative to each other, the friction between the fluid inside the shock absorber and the bore walls creates resistance to the body vibrations; this resistance is engineeringly called damping force. Damping force converts the vibration energy of the body into heat energy, which is absorbed by the fluid and the housing. To better achieve a smoother ride and greater safety, the damping coefficient is not fixed to a single value but varies with the car's operating conditions, ensuring the suspension performance is always near its optimal state. Therefore, some car shock absorbers are adjustable and can automatically select based on sensor signals.
