Global Positioning System: A useful tool for Intelligent Vehicle-Highway Systems (IVHS)
The general conclusion is thus that GPS has much to offer as a vehicle identification and monitoring tool for IVHS application.
This paper presents some of the applications of the GPS in Intelligent Vehicle Highway Systems, like improving trip reporting, travel time studies, dynamic route guidance (DRG), vehicle navigation and tracking. An experiment has been planned, to carry out travel time and delay studies and to estimate the congestion on the roads, on some important roads in Mumbai.
Applications
The various important applications of GPS in IVHS include:
Trip Reporting
Classical methods of trip reporting have disadvantages like the poor data quality on travel start and end times, total trip times and trip destination (Sivaram and Kulkarni, 2001). A project study was conducted in Lexington, Kentucky in fall, 1996 where GPS was used to capture vehicle-based, daily travel information. The project used a computer for computer-assisted self-interviewing, combined with GPS system. Though the design of equipment required the respondents to actively turn the computer on each time they made a private vehicle trip, the GPS component could capture the “actual” travel rather than the self-reported travel. The driver had to actively select the driver and passenger names, and their trip purposes. The GPS component captured date and time, and latitude/longitude data every three seconds when a trip had begun, so that the trip start and end times were passive data elements to the respondent. The advantage of passive data recording is that respondent burden is minimized and the travel times and distances that were collected represent the true picture about the length and duration of the trip.
The usage of computer for computer-assisted-self-interviewing has helped to capture data regarding trip purpose and vehicle occupancy. Having the data regarding the trip purpose, occupancy, together with the route choice and travel speed, would provide planners with the information that could be used in evaluating management systems, designing ITS, etc. To further reduce the burden on the driver, GIS can be integrated with GPS. The GPS data, after exporting to a GIS can be viewed on the map. The use of GIS helps in knowing the destination of the trip, without the driver intervention, and also in knowing the particular route the driver had chosen to reach his destination. Though GIS has not been used in the research mentioned above, its usage for the trip reporting purpose will definitely improve the trip reporting procedure (Murakami and Wagner, 1999).
|
