Travel time, speed, and delay analysis using an integrated GIS/GPS system (original) (raw)

Evaluation of the accuracy and automation of travel time and delay data collection methods

2010

Travel time and delay are among the most important measures for gauging a transportation system's performance. To address the growing problem of congestion in the US, transportation planning legislation mandated the monitoring and analysis of system performance and produced a renewed interest in travel time and delay studies. The use of traditional sensors installed on major roads (e.g. inductive loops) for collecting data is necessary but not sufficient because of their limited coverage and expensive costs for setting up and maintaining the required infrastructure. The GPS-based techniques employed by the University of Delaware have evolved into an automated system, which provides more realistic experience of a traffic flow throughout the road links. However, human error and the weaknesses of using GPS devices in urban settings still have the potential to create inaccuracies. By simultaneously collecting data using three different techniques, the accuracy of the GPS positioning data and the resulting travel time and delay values could be objectively compared for automation and statistically compared for accuracy. It was found that the new technique provided the greatest automation requiring minimal attention of the data collectors and automatically processing the data sets. The data samples were statistically analyzed by using a combination of parametric and nonparametric statistical tests. This analysis greatly favored the GeoStats GPS method over the rest methods.

Using GPS to Measure Traffic System Performance

Computer-Aided Civil and Infrastructure Engineering, 1999

Traffic system performance can be measured in various ways, but from the user perspective, congestion is the major criterion. This article examines some novel uses of GPS in the measurement of vehicle speeds and travel times and their synthesis into measures of congestion and ultimately of the performance of the urban road system. The article also will discuss the integration of GPS-based congestion measures into an ITS framework, techniques for implementing a congestion-monitoring system, and implications for urban road system planners, managers, and users.

Urban Traffic Speed Management: The Use of GPS/GIS

1977

The prevailing traffic speed at any section of a roadway affects the quality of traffic at the time. Whereas excessive speeds affect the severity of road traffic accidents, crawling speeds in the urban environment is also indicative of congestion. One of the key elements in speed management planning is the functional classification of roads by speed. For example, 30km/h has been designated for residential areas and 60km/h and above for major arterial roads. Nowadays, efficient vehicle monitoring can be achieved by integrating Global Positioning System (GPS) derived traffic data such as vehicle speed and direction of traffic flow into a Geographical Information System (GIS) environment. This GPS-GIS integrated system provides real-time meaningful location and status of the vehicles in the network. The system has been used to show the second-to-second positional changes in speed and directions of vehicles travelling in Kumasi, the second largest city in Ghana. Using the geographic components in a dataset and visualizing the results in a map provided a clearer picture of the traffic-state of every route in the network. The GPS has clearly indicated the road sections where speeds are unacceptable and driver behaviour is affected giving transport planners the option to choose the desired speed management technique to improve the traffic system.

GISTMARG: GPS and GIS for Traffic Monitoring and Route Guidance

Cell phone providers have started fitting assisted global positioning system (AGPS) chips in new cell phones. The phone users travel on the roads voluntarily and if the phones can be queried anonymously at a reasonable cost, the phones can replace costly dedicated probe vehicles. The major challenge in using AGPS chips is that the phones may not always be on the roads. Even if they were on the roads, they could be in different modes of transportation. Since traffic conditions are usually monitored in terms of private automobiles, the modes of transportation the phones are in first needs to be determined in order for them to be used as traffic probes. Once the traffic data is correctly identified as coming from the private automobile mode, it is another challenge to combine the information with different information sources. This thesis develops a method to fuse the multiple sources of traffic data for more reliable estimation of traffic conditions. Traditionally, route guidance systems generally have focused on the shortest or the fastest route for a particular pair of origin and destination. However, by utilizing available three dimensional (3-D) and geospatial data, it is possible to aid route guidance systems that are optimizing for other objectives such as finding the most scenic, the most level or the safest route. "The fear of the LORD is the beginning of knowledge" (Proverbs 1:7) I thank God for helping me throughout the research and using me for plans He has for me. I would like to acknowledge all those who contributed either directly or indirectly to this research. First of all, I would like to express my deep sense of gratitude and indebtedness to my supervisors Prof. Baher Abdulhai and Prof. Amer Shalaby who gave me the opportunity to conduct this research. They both guided me with specific research directions and financially supported me throughout the research period. Without them, it would have been impossible to complete this Ph.D. thesis work. I would like to thank Prof. Eric J Miller and Prof. Matthew Roorda for equipping me with the fundamental knowledge in transportation through their courses and providing me with career related advices throughout my thesis work. I would like to acknowledge Samah El-Tantawy and Hossam Abd El-Gawad for helping me with the QQ network micro-simulation in the model verification stage in this thesis. I would like to thank all my family members Sung-Sang Byon, An-Soon Byon and Ji-Hyun Byon for their support and prayers. I also thank Hak-Chul Choi, Young Ja Choi, Hyo Sang Byon and Bok Ae Byon for being my mentors.

GPS Vehicle Tracking in Urban Areas

Proceedings of the Eighth International Conference on Engineering Computational Technology, 2012

The main objectives of this research were to utilise GPS vehicle tracking techniques to measure and analyse operating speed, travel time, and delay time for urban arterial roads and to develop operating speed models to estimate speed profiles based on roadway environments. Statistical regressions were carried out to establish useful models to estimate operating speeds at segments and horizontal curves, and acceleration and deceleration distances from the mentioned variables. The results of this investigation indicated that: 1) On-street parking, section width, corridor function, number of median opening, number of horizontal curves, length of corridor, number of access points, and number of humps were found to be the most significant contributors to operating speed while the significant variables of horizontal curve model were entering speed, deflection angle, posted speed limit, and combination of horizontal curve and vertical curve; 2) The minimum length of study corridor can be determined after analysing and understanding vehicle acceleration and deceleration characteristics from vehicle tracking of the GPS that is related to final speeds or approach speeds, and posted speed limits.

Final Report Advanced Applications of Person-based GPS in an Urban Environment

2011

Disclaimer The contents of this report reflect the views of the authors, who are responsible for the facts and the accuracy of the information presented herein. The contents do not necessarily reflect the official views or policies of the UTRC or the Federal Highway Administration. This report does not constitute a standard, specification or regulation. This document is disseminated under the sponsorship of the Department of Transportation, University Transportation Centers Program, in the interest of information exchange. The U.S. Government assumes no liability for the contents or use thereof. Traditional travel surveys provide essential information on travel patterns, but are time-consuming, expensive, and have seen declining rates of participation. Recently global positioning systems (GPS) technologies have been introduced to facilitate the data collection process. While GPS traces can provide accurate information on the location and time of travel, these traces do not contain e...

Analysis of Day-to-Day Variations of Travel Time Using GPS and GIS

Proceedings of the Third …, 2002

This paper presents an analysis of day-to-day variations of travel time on road network using G lobal Positioning System (GPS) and Geographic Information System (GIS). Data collection system was developed using GPS connected with notebook PC, which can capture vehicle movement of multiple days. One-week vehicle travel surveys using the system were conducted for commuting drivers in local cities. Methods for handling GPS data on GIS platform were summarized, and day-to-day variations of travel time and speed were analyzed in the study area. Although positional data are very promising, usefulness in travel time studies depends on the process of data handling and the quality of GIS database.

Arterial Speed Studies Based on Data from GPS Equipped Probe Vehicle

Journal of the Eastern Asia Society for Transportation Studies, 2015

Due to more complicated behavior than controlled access roadway, congested estimation on arterial road network has become a challenging topic for all traffic professionals in recent years. To indicate the traffic condition, link travel speed is considered as one of the important markers for representing traffic status on roadway network and most understood pointer for all road users. This paper describes the implementation of Running Speed and Stopped Delay (RSSD) technique for investigating the urban link travel speed and discusses on the limitation of error in speed associated from each global positioning system (GPS) device to maintain the advantages of proposed technique in travel speed estimation. The results from real observation traffic data on urban roadway also confirm that the accuracy of travel speed estimation is significantly improved when RSSD was employed as the estimation technique compared to baseline approach particularly in the links with highly congested condition.

Utilization of GPS Travel Time and Delay Data for Optimal Routing

IFAC Proceedings Volumes, 2009

Traffic congestion during peak hours has become one of the major problems affecting the road networks. GPS, in coordination with data retrieving software has been used for various purposes ranging from commercial utilization (route guidance systems) to monitoring traffic by different transportation organizations. In this research, collection of travel time and delay data on a congested network is used to obtain results that enable a commuter to make intelligent choices regarding his or her route. Travel time and delay data retrieved from a GPS instrument attached to a test vehicle traversing the study area during peak hours has been used to determine an optimal route between any given origin and destination in the area. The data collected on each road segment was analyzed and fitted into distributions. Using these distributions, the estimated travel time on each segment was inferred and the probability of being delayed was determined. The travel time and delay data in the form of Microsoft Access tables was imported into the GIS and programmed using a Visual Basic code, such that a user-friendly tool written in Visual Basic using ArcObjects was developed which provides the user with the optimal route between two selected points in the network, the travel time required to traverse the route, and the probability of being delayed on the route. In addition to this data, travel time maps are generated for the network, which provide a visual display illustrating the road network around a reference point for a given time.