A four degrees-of-freedom half-car model.
This is an extended model of half of a car and is used to predict the bouncing as well as the pitching motion of the car (Figure 4). Note that the front and rear suspension can have different parameter values. In this case, the excitation from the road to a moving vehicle will affect the front wheels first and the rear wheels later. This results in a pitching motion which can be very annoying, much more than bouncing.
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Figure 4. A Four degrees-of-freedom half-car model