Specifications

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These intersections and camera positions were chosen in order to test the system on a variety of
backgrounds. Each background represents a different type of potential source of false alarms in
the object detection process. The first urban intersection has a large tree in the background. The
second and third urban intersections contain a view of the road crossing the lane of interest. The
last urban intersection contains a large window that reflects light from passing vehicles. Three of
the urban intersections are three-way stops, while one intersection is a four-way stop. The urban
intersections are on the Iowa State University campus and experience heavy vehicle and
pedestrian traffic during the day. Video was recorded from each intersection during the hour of
4:00 p.m., one intersection per day. Video was also recorded from a single intersection at 4:00
p.m. on four different days in the case that traffic varied as a function of day of the week. The
rural intersection is a one-way stop where a low-volume road meets a high-volume, high-speed
road. As can be seen in Figure 5.2, the stop sign on 190th is set well back from U.S. 69. Also,
note that the traffic on U.S. 69 is visible. The collision diagram was provided by the Iowa DOT
and shows the collisions within 500 feet of the intersection (inside the circle) in red and the
remainder of collisions in green.
Figure 5.2. A collision diagram (1995-2005) of U.S. 69 and 190th and a corresponding video
frame