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able to detect a pedestrian placed in the car trajectory. In the first tests the car
decelerates if a pedestrian was detected but, when the automatic actuation on the
brake pedal was available, the emergency brakingwas possible in front of a pedestrian
(Llorca et al. 2011 ).
When we had three vehicles available the AUTOPÍA aims pointed out to coop-
erative maneuvers with several cars, in particular to risked maneuvers like crossing
road intersections, overtaking, going in- or out-a platooning, merging, etc. (Alonso
et al. 2011 ; Milanés et al. 2011a , b ). Overtaking maneuvers which involved three
vehicles running simultaneously by a road of two lanes, one for each sense of cir-
culation, were simulated first and later tested in real experiments. For this risked
maneuver a decision algorithm estimated in real time if the traffic conditions allowed
to complete the overtaking or it has to be aborted. For crossing road intersections
the decision algorithms analyzed the current state variables of cars—position and
velocities mainly—to assign them priorities of passing.
In Naranjo et al. ( 2007 ) are described the decision procedures to coordinate the
crossing maneuver, their implementations, simulations and future perspectives. In
2009 we added an inertial control unit (IMU) to the localization system and a new
braking system in parallel with the input of the ABS of the car (Onieva et al. 2010a ).
These systems improved the car controllers, the first allowed to located the vehicle
when the signals satellite fail during a short time and the second allowed the cars
to break suddenly in front of emergencies, as if an obstacle or pedestrian intervene
in the route (Pérez et al. 2011 ). In Onieva et al. ( 2010b ) is described an adjustment
of the steering wheel controllers by means of genetic algorithms, this research was
done to obtain lateral controllers that behave like human drivers in several situations,
in particular to follow a previous known route in a comfortable way. In order to do
this work the state of the vehicle was monitored while was driven by a person and
a fuzzy controller to deal with the steering wheel has been provided by means of
genetic algorithms.
The capacity of interoperation of the AUTOPÍA control architecture has been
proved with experiments. In particular during the Cybercar2 project tests were real-
ized in two places in France, Versalles July 2008 and La Rochelle September 2008,
to communicate the different kinds of vehicles of the project partners; in both cases
one cybercar of INRIA, one Smart of TNO and one C3 Citroën of AUTOPÍA com-
municate messages among them to run cooperatively by means of ACC controllers
(Fig. 11.3 ).
Analogously, to prove the flexibility of the AUTOPÍA control architecture maneu-
vers involving vehicles driven in a manual or automatic way have been managed. In
order to do it the “Monitor” program was developed to broadcast messages with the
position and velocity of one vehicle to the other ones present into a certain range.
During the development of AUTOPÍA the control procedures have been improved
continuously. Some of these improvements have been a discrete PID controller for
the steering wheel with two control modes, new braking modules and a redefinition
of the control architecture.
In Pérez et al. ( 2011 ) the evolution of the AUTOPÍA control system is described
as well as a cascade control to improve the lateral controller and its application to
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