Page 290 - Introduction to AI Robotics

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7.4 Managerial Architectures
Sensors Strategic Behaviors Tactical Behaviors Actuators
Inclino-
meter
slope
Safe Velocity

Camera Drive
Follow-Path Strategic Speed-Control
Velocity Motor

Clutter Direction To Path
Camera Direction
Sonar Avoid Steer
Obstacles
Motor
How Much Vehicle Turns
Swivel Camera
Camera
Center-Camera Pan
Motor

Figure 7.6 Strategic and tactical behaviors for following an outdoor path, used in
the 1995 UGV Unmanned Ground Robot competition.

ensure that the robot acts in a safe manner in as close accordance with the
strategic intent as possible. The interaction of strategic and tactical behaviors
is still considered emergent behavior.
One outcome of the strategic-tactical partitioning was the discovery that
every task to date could be done with one strategic behavior and several
tactical behaviors. This means that the need to combine behaviors does not
occur often, and so the combination mechanism is not particularly important.
However, it should be emphasized that the strategic behaviors were often
assemblages in the form of scripts. There were many strategic behaviors,
but they were explicitly coordinated and controlled according to behavior-
specific knowledge.