The DCS was intended to recognize the presence of external risk factors that may be incorporated
into the algorithms for driver feedback or vehicle adaptation. The focus was on environmental
factors related to visibility limitations or vehicle control, some of which can be monitored through
vehicle dynamics (e.g., traction control).
The ideal implementation should take advantage of information that can be inferred from the
several vehicle sensing systems. For example, time of day can be obtained from GPS and vehicle
clock time, precipitation may be inferred from windshield wiper use and roadway icing can be
inferred from temperature, humidity, and traction control features.
For the demonstration and FOT implementation efforts only the time of day was used. The time of
day was collected from the GPS signal obtained as part of the speed management subsystem and
then compared to sunset and sunrise times to identify day or night driving.
No other subsystems were needed for this subsystem to operate. However, the DCS was necessary
for input into the SMFS and EMFS by providing important driving context factors (e.g., day or
night). The DCS combined with data from inside the vehicle (passengers, distraction, seat belt use)
served to refine the response of other subsystems.