Ruilin Liu

Ph.D. Candidate
Department of Computer Science
Rutgers, The State University of New Jersey
Office: CoRE 333
Email: rl475 [at] cs [dot] rutgers [dot] edu

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Themis: City-Scale Balanced Routing for a Better Traffic Ecosystem

The highlights of state-of-art online routing services still lie on collecting accurate traffic infomation and applying the traffic information to provide users with individual best route solutions. However, as the prevelance of navigation devices & apps, the traffic following the planned routes has been increaseing to considerable portion so that the impacts of these users' routing choices should become a non-negliectable factor when routing subsequent vehicles. This project builds a balaned routing system to use this potential factor to benifit both individual drivers as well as traffic management in urban area.



The balanced routing system consists of a central server and smartphone applications deployed on drivers' mobile phones. The central server works as traffic collector and routing request handler. When driving, users simply open the balanced routing client application in their smartphone and use it as regular navigation application. The functionality of balanced routing system can be divided into three parts:

  • Participatory traffic sensing - During regular driving, the client application periodically samples travel states (such as location and instant speed) and reports it the to server, where Floating Car Data (FCD) based techniques are applied to use the samples to get the aggregative traffic condition including average travel time and traffic count on each road segment.

  • Routing request & balanced solution - Before starting a trip, driver makes routing request. Then the routing server runs the balanced routing algorithm and returns the routing solution to client application, where it is used to porvide driver with step-by-step driving assistance. Balance routing algorithm works based on realtime traffic, but when receiving the routing request, it doesn't aim merely at minimizing travel time for the proposed request but aims at minizing overal travel time of all up-to-now requests proposed to the routing system or even including future requests.

  • Proactive congestion avoidance - When the server recognize the signal of congestion, it automatically recalculates the route for relevant vehicles and sends to corresponding clients. If got approved by driver, the rerouting will take place and so the traffic will be redistributed to avoid forthcoming congestion.

Ruilin Liu
Last updated on Dec. 5, 2014