Abstract:

Many types of traffic studies require collecting field data. From traditional intersection turning movement count, travel time, and approach delay, to more advanced studies such as driver conflicts, origin-destination, and vehicle trajectory, etc. Many technologies are available to collect the above data; cost, accuracy, and power run duration are the main factors affection the selection of technologies for specific study. This presentation highlights FHWA Intersection Safety R&D’s experience of collecting field traffic data at large intersections/interchanges. The data collection sites included diverging diamond interchange, displaced left-turn interchange, continuous flow intersection, and multi-lane roundabouts, etc. The technologies used evolved from traditional on-the-ground technologies, which often fill a cargo van full of equipment and auxiliaries, to aerial surveys using helicopters, and recently drones. Comparing to traditional technologies, aerial survey offers the advantages of less personnel, larger coverage area (field of view), no disturbance to traffic flow, and often lower cost. The types of traffic data that can be derived from aerial surveys includes peak hour intersection turning movement count, spot speed, travel time between designated origins and destination pairs, queue length by approach, and the origin-destination matrix of a regional roadway network, etc. With aerial survey, management of raw data also becomes significantly simpler. Stunning quality videos and imagery can be obtained economically from drone based cameras, making them ideal material for illustrating the operating principle of various types of innovative intersection/interchange designs. The author will discuss the tremendous opportunities provided by drone affiliated technologies in various types of traffic and driver behavior studies, as well as the limitation of this technology under current regulation.