Traffic behavior in a mixture of different vehicles

The car following models are extended to take into account the characterist ics of different vehicles. The characteristic of each car can be included i n the parameter of the dimensionless delay time. The traffic behavior is in vestigated, analytically and numerically, under the periodic boundary condi tion. At a low density, all the vehicles move at a constant velocity. When the density is larger than the critical value, the traffic flow becomes uns table and the density waves appear. The jamming transition does not depend only on the mean value of the dimensionless delay time but also on the vari ation. With increase in the variation of dimensionless delay time, the jamm ing transition occurs at a higher value of the mean value. It is found that the variation of vehicles stabilizes the traffic flow and suppresses the t raffic jams. The transition line obtained by the linear stability analysis is compared with the simulation result. (C) 2000 Elsevier Science B.V. All rights reserved.