Title :
Obtaining Dense Road Speed Estimates from Sparse GPS Measurements
Author :
Phan, Andrew ; Ferrie, Frank
Author_Institution :
Dept. of Electr. & Comput. Eng., McGill Univ., Montreal, QC
Abstract :
A major challenge for traffic management systems is the inference of traffic flow in regions of the network for which there is little data. In this paper, GPS-based vehicle locator data from a fleet of 40-60 roving ambulances are used to estimate traffic congestion along a network of 20,000 streets in the city of Ottawa, Canada. Essentially, the road network is represented as a directed graph and a belief propagation algorithm is used to interpolate measurements from the fleet. The system incorporates a number of novel features. It makes no distinctions between freeways and surface streets, incorporates both historical and live sensor data, handles user inputs such as road closures and manual speed overrides, and is computationally efficient - providing updates every 5 to 6 minutes on commodity hardware. Experimental results are presented which address the key issue of validating the performance and reliability of the system.
Keywords :
Global Positioning System; belief networks; interpolation; road traffic; road vehicles; sensors; traffic information systems; GPS-based vehicle locator data; Global Positioning System; belief propagation algorithm; dense road speed estimation; directed graph; freeway street; interpolate measurement; live sensor data; road network; roving ambulance; sparse GPS measurement; surface street; traffic congestion; traffic flow; traffic management system; Belief propagation; Cities and towns; Fluid flow measurement; Global Positioning System; Intelligent networks; Intelligent transportation systems; Roads; Telecommunication traffic; Vehicles; Velocity measurement;
Conference_Titel :
Intelligent Transportation Systems, 2008. ITSC 2008. 11th International IEEE Conference on
Conference_Location :
Beijing
Print_ISBN :
978-1-4244-2111-4
Electronic_ISBN :
978-1-4244-2112-1
DOI :
10.1109/ITSC.2008.4732598