Applications of GIS and GPS in Travel Time Studies and Delays
Mukund Dangeti
Research Assistant
Transportation Research Center
USA
Email: mukund@Egr.UNLV.EDU
Srinivas Pulugurtha
Abstract
Evaluation of transportation software simulation programs typically involves comparison of simulation results with field measurements of vehicle travel times, delays and queues. Collection of such field data is normally done manually, requiring a lot of manpower, time and money, especially if it has to be done at network level. However, the same information can be collected more efficiently by integrating advanced software and hardware technologies such as Geographic Information Systems (GIS) and Global Positioning Systems (GPS). With the installation of ArcPad Software on handheld units (like HP IPAQ 5555), data can be collected at regular time intervals by placing these handheld units on a moving vehicle. This data can then be processed later to extract travel time and delay estimates. The primary advantage by using this procedure is that data collection can be done with minimal personnel requirements. An added benefit is that the data can be used to verify the spatial accuracy of the road network, identifying omitted or misaligned road segments. Using GPS for collection of vehicle speed data in this manner has allowed for the incorporation of inexpensive, realistic travel time data and resulted in more reliable network analyses.