  In this report, we apply an input-output transformation passivation method,
described in our previous works, to an Adaptive Cruise Control system. We
analyze the system's performance under a co-simulation framework that makes use
of an online optimization method called extremum-seeking to achieve the
optimized behavior. The matrix for passivation method encompasses commonly used
methods of series, feedback and feed-forward interconnections for passivating
the system. We have previously shown that passivity levels can be guaranteed
for a system using our passivation method. In this work, an extremum-seeking
algorithm was used to determine the passivation parameters. It is known that
systems with input-output time-delays are not passive. On the other hand,
time-delays are unavoidable in automotive systems and commonly emerge in
software implementations and communication units as well as driver's behavior.
We show that by using our passivation method, we can passivate the system and
improve its overall performance. Our simulation examples in CarSim and Simulink
will show that the passive system has a considerably better performance.
