An Investigation of Urban Link Travel Time Estimation Based on Field Sparse Probe Vehicle Data

From past several years, the interest to use probe vehicles for traffic monitoring is growing. Mainly vehicles equipped with GPS are used as traffic sensors to collect traffic data (speeds, positions and time stamps) in the urban road network. However, due to the low polling frequencies, travel times recorded by probe vehicles are for partial link or for partial route travel. This paper focuses on the estimation complete link or route travel times. Two methods are adopted to allocate travel times collected by probe vehicles between two consecutive time stamps into individual links. One method was the probabilistic method developed by Hellinga and the other is distance-proportion method. Two field data sets are used to verify how these two methods perform in different traffic conditions. The results show that for the low traffic demand condition, when the polling interval is low (e.g. 15s, 30s), both methods can work well. In the case of a high polling interval (e.g. 60s), Hellinga’s method performs worse than distance-proportion method. However, in the high traffic demand condition with 60s polling interval, Hellinga’s method works better with Mean Absolute Percentage Error (MAPE) of 11.64% compared with the distance-proportion method with MAPE of 17%. In Hellinga’s method, the link travel time is subdivided into free flow travel time and delay. The sensitivity of the performance of the method to different free flow speeds is also investigated in the paper. Results show that in low traffic demand condition with 60s polling interval, free flow speeds have significant influence on the estimation results.

Language

  • English

Media Info

  • Media Type: DVD
  • Features: Figures; References; Tables;
  • Pagination: 18p
  • Monograph Title: TRB 89th Annual Meeting Compendium of Papers DVD

Subject/Index Terms

Filing Info

  • Accession Number: 01154636
  • Record Type: Publication
  • Report/Paper Numbers: 10-2522
  • Files: BTRIS, TRIS, TRB
  • Created Date: Jan 25 2010 11:12AM