Defining the Conflict Zones
The current videos from cameras do not depict an area for analysis (some type of marker) to identify the "Conflict Zone" under AI inspection. Is it implied that a method will be included in the implementation design to provide this information, or will that be provided in some manner by the local DOT?
Wei Zhang commented
An intersection involves two intersecting roads. The road that carries higher traffic demand and (usually) with higher speed limit is the major road. An major approach is a leg located on the major road.
Ben Mains commented
“For this study, focus the dilemma zone analysis on high speed (over 40 mph) vehicles on the major approaches only during the Yellow phase. ”
What is a major approach in this context?
Wei Zhang commented
This study calls for identifying vehicles in two types of zones: dilemma zone, and trajectory conflict zone. The dilemma zone is a segment upstream of the intersection (for this study, consider the dilemma zones on major approaches only), from which it takes a vehicle 2.5 sec to 5.5 sec to travel to the intersection stop bar. The dilemma zone is a function of detected vehicle speed. For a vehicle approaching the intersection at 45 mph (66 ft/s), its dilemma zone starts at 363 ft and ends at 165 ft upstream of the intersection; for another vehicle approaching the intersection at 50 mph (73.3 ft/s), its dilemma zone is 403 ft to 183.3 ft upstream of the intersection. For this study, focus the dilemma zone analysis on high speed (over 40 mph) vehicles on the major approaches only during the Yellow phase.
Although trajectory conflict can happen anywhere, for this study, the focus may be placed in the area within 75 ft of the intersection stop bars (include the pedestrian crossings). Trajectory conflicts may be vehicle-vehicle, vehicle-cyclist, and vehicle-pedestrian. The time-to-collision of detected trajectories may range between 0 to 2 seconds (this is an arbitrary threshold for now).
The offeror should explain how they intend design and implement algorithms to fulfill the requirements.