An approximation of the effective force actually realized
by the real damper is needed for the feedback loop. In
case of the model-based approach, the damper force ˆFd,m
is generated by a parallel simulation of the dynamic damper
model, driven by the acting relative velocity ˙xcw and the
current i∗, see Fig. 2. The second method investigated is a
signal-based technique, which makes use of the measured
body acceleration and of an estimation of the chassis mass.
Solving the chassis equation of motion in (1) with respect to
Fd(x, i∗) and applying the measured and estimated signals,
an estimation of the acting damper force is given by