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62                        Olmer Garcia and Cesar Diaz

                       field  (Siegwart,  Nourbakhsh,  &  Scaramuzza,  2011).  The  navigation  field  organizes  its
                       techniques  into  two  groups:  planning  and  reacting.  The  techniques  from  the  planning
                       group are known as global path planning and are concerned with the generation of the
                       global  route  that  guides  the  vehicle  toward  a  goal  position.  The  techniques  from  the
                       reacting group are known as local path planning and are concerned with the generation of
                       several  local  paths  that  allow  the  vehicle  to  avoid  obstacles.  In  this  layer,  machine
                       learning techniques are used to select routes (global and local).
                          Finally, the control layer will manipulate the degrees of freedom of the autonomous
                       vehicle  (e.g.,  steering,  braking,  gearbox,  acceleration)  for  bringing  it  to  the  desired
                       position  at  a  defined  speed  at  each  instant  of  time.  Machine  learning  techniques  have
                       been used to obtain mathematical models and/or adapt a controller to different situations.































                       Figure 4. Interactions of the proposed cooperative strategy with the architecture of the autonomous
                       vehicle VILMA01 (Bedoya, 2016).

                          This research studies the architecting of the layers using a cooperative strategy based
                       on  risk  analysis.  The  resulting  architecture  includes  mechanisms  to  interact  with  the
                       driver (this architecture has been proposed in VILMA01 - First Intelligent Vehicle of the
                       Autonomous Mobility Laboratory). We stated above that the motion control layer is the
                       one in charge of manipulating the degrees of freedom of the car (steering, braking, and
                       acceleration). This manipulation will bring the autonomous vehicle to the desired position
                       at each point in time. We will explain that this can be achieved by using a predictive
                       control  technique  that  relies  on  dynamic  models  of  the  vehicle  to  control  the  steering
                       system.  The  path-planning  layer  will  have  the  reactive  part  also  known  as  local  path
                       planning, where the desired path is represented in a curvilinear space. The desired path is
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