CAS module
The CAS (Collision Avoidance System) Module takes as inputs the relative positioning information provided by the RGNSS module and the information received from other vehicles through the vehicle-to-vehicle communication link.
With all that information it tries to predict the relative dynamics of the vehicles on the road and the possibility that a collision takes place in the near future. When such an event is foreseen, an alarm is raised for the user to be aware of a dangerous situation that might evolve quite fast and with dire consequences.
By providing an alarm to the driver some seconds in advance, he is more aware of the danger, decreasing the reaction time needed to either avoid completely the threat or at least minimize the damage.
CAS module can also use local and external sensor information to have a better estimation on the real attitude evolution of the vehicle.
CAS module takes into account on one hand the Relative Vector dynamics between pair of vehicles and the individual dynamics of each single vehicle. The nearer between both vehicles, the more accurate and confidence the collision diagnosis is.
CAS module has been designed to provide three warning levels (YELLOW, ORANGE and RED) with respect to the estimated Time To Collision (TTC). Within REPOSIT: YELLOW and ORANGE levels are used only for awareness, without much confidence on a single diagnosis. On counterpart, RED level has to provide enough confidence related to a real danger.
The following pictures show the Time To Collision and the Alarm Levels. Three cases are shown:
- Longitudinal case: two vehicles in different lanes going on opposite directions. (No CAS warning is shown here)
- Intersectional case: Two vehicles colliding in an intersection. (CAS Warning)
- Roundabout: Along an uphill road, a quicker vehicle tends to collide against slower trucks. (CAS warning shown here)
