Route control for freeway networks via nonlinear optimization approach

This paper is concerned with route control for freeway networks. The freeway network with multi-origin and multi-destination was modeled using a second order macroscopic traffic flow model. The nonlinear optimization method for traffic control was presented. The considered control measure was route diversion by Variable Message Signs (VMS).The control task was formulated as a dynamic, nonlinear, discrete-time optimal control problem with constrained control variables. Considering the characteristic of nonlinearity of this control problem, a gradient algorithm, which was imbedded by a Quasi-Newton search algorithm, presented. A simulation result for route diversion was given through a test example. From the result, we prove the presented gradient algorithm is efficient and applicable in increasing the network performance.