This subsystem makes
driving decisions. Most steering is done by the OpenSteer
system, using input data from the sensor visualization subsystem.
OpenSteer is a field-based steering control system - the vehicle
is attracted to the next waypoint, attracted to the road location,
and repelled by obstacles and untraversable ground.
OpenSteer can't handle
dead ends. The "backseat driver" monitors the performance
of OpenSteer, and when it's stuck, inserts subgoals to take the
vehicle in a different direction. The "backseat driver"
has a vicinity map of what the vehicle has seen recently, and access
to a a path planner that can solve simple mazes.
Outputs from OpenSteer
are monitored by low-level safety and sanity checks, which use sensor
data (primarily the VORAD radar and the sonars) to veto actions
from the steering system.
This system's performance
can be monitored by watching the field map and the vicinity map.