This paper presents the history of and current status of a U.S. DOT and NASA sponsored program designed to demonstrate the feasibility of using a small-unmanned airborne data acquisition system (ADAS) for traffic surveillance, monitoring, and management. ADAS is ideally suited for application in monitoring traffic flow, traffic congestion, and supporting ITS assets. GeoData Systems (GDS), Inc., with principal offices at 10565 Lee Highway, Suite 100, Fairfax, VA 22030 has developed a revolutionary new class of airborne data acquisition systems. In this effort, GDS has teamed with traffic experts DBR & Associates; P.O. Box 12300 Burke, VA. The GDS ADAS has a gross takeoff weight of less than 55 lbs, which includes both the airframe and sensors. It is capable of sustained flight for periods in excess of two hours while carrying a sensor payload of up to 20 lbs. ADAS has nine interchangeable sensor platforms under development to include a hyper-spectral visible-near-IR sensor, a multi-spectral visible near-IR mid-IR sensor, a synthetic aperture radar (SAR) sensor, and a highly flexible high-resolution real-time video sensor. The GDS high-resolution real-time video sensor is ideally suited for traffic monitoring and other highway monitoring applications. The ADAS platform is capable of flying under a combination of pre-programmed Differential Global Positioning Satellite (DGPS) based navigation and manual direct ground control. The ADAS is being fully tested and is planned for use in several DOD base-monitoring studies this year. It should be noted that the ADAS has several levels of backup systems, which allows for a safe descent to the ground via parachute in a worst-case scenario. The system and any liability resulting from its use are fully insured by a major provider. The use of ADAS in traffic surveillance, monitoring, and management is unique and, as far as can be ascertained, has not been used in an official capacity in this way. Because of its ability to collect traffic data, survey traffic conditions, and collect highway inventory and environmental data in a cost-effective manner, and because every metropolitan area needs to collect at least some traffic data, the potential payoff from applying the ADAS is significant. The estimated potential payoff resulting from the use of the ADAS was calculated by taking into consideration information from a recent study conducted for the Federal Highway Administration by the Volpe National Transportation Systems Center1. Using a reported average amount of funds expended annually for traffic data collection by transportation agencies in metropolitan areas with a population of over 200,000 and taking into consideration the estimated budget for staff involved in data collection, it is calculated that transportation agencies in an average metropolitan area spend approximately $5 million per year in traffic data collection. The ADAS can play a cost-saving role in about half of all data collection procedures and can reduce the total cost by 20 percent. Nationally, this could produce an annual savings of $75 million. An additional area where the ADAS can play a useful role is in incident management. It is well documented that more than half of the traffic congestion in the U.S. is caused by incidents, and the problem is getting worse: The percentage of congestion due to incidents is estimated to increase to 70 percent by the year 20053. The Federal Highway Administration further estimates that incident-related traffic congestion will cost the U.S. more than $75 billion in the year 2005, mainly due to lost time and wasted fuel. Comprehensive, accurate surveillance of major incidents will result in a more effective overall response. It can facilitate the process of completing police documentation of incidents, which further reduce their duration. A recent study4 showed that a 23-minute reduction in average incident duration in the Atlanta area saved $45 million in one year. The ADAS is able to provide real time overhead video feeds of an incident and the surrounding traffic situation. In addition, the ADAS can record the incident on video, capturing especially those incidents that are not within the visibility range of any CCTV system, therefore reducing the recording burden of police officers. The valuable role that airborne real-time video can play has been recognized by transportation agencies: The Virginia Department of Transportation (VDOT) has commented enthusiastically on this approach: “…VDOT definitely supports the use of an Unmanned Airborne Sensor for traffic management during a highway incident.” In addition, the Director of the Center for Advanced Transportation Technology of the University of Maryland also has responded positively, writing that, “A project which evaluates the effectiveness of an unmanned airborne data acquisition system in monitoring traffic flow seems to be a step in the right direction toward identifying appropriate and cost-effective remote sensing applications.” Further, in a recent study conducted by the Virginia Transportation Research Council in cooperation with the Federal Highway Administration, researchers concluded that: “the air video reduces the time and personnel needed to acquire data from the field. Further, aerial video may facilitate an objective evaluation of a jurisdiction’s incident response procedures. Finally, aerial video may allow a transportation agency to adopt a proactive approach to traffic management by identifying and evaluating potential problems before they occur. Specifically, problems include the use of residential neighborhoods to bypass congested arterials and heavily used facilities needing snow removal.” Our project is demonstrating how the ADAS can be used in traffic surveillance monitoring and management. The study team is using input from transportation agencies at the state and local level to fine-tune the design of the ADAS application and the analysis and evaluation of the results. Areas where the ADAS can be applied effectively and efficiently are being identified. When completed, the end product of this effort will be a document that will indicate when it is cost-effective to use ADAS relative to other possible methods of data collection and analysis.
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