Modelling the Impact of ACC-Systems on the Traffic Flow at Macroscopic Modelling Level

Within the area of transport telematics, systems like adaptive cruise control systems (ACC-Systems), early warning systems, etc. are developed or improved. Recently ACC-Systems are launched into the market, so the penetration rate will increase in the future. ACC-Systems were researched very detailed by using microscopic models or by field tests with a limited number of equipped vehicles. The expected impact of this systems on the traffic flow was shown by microscopic analysis for different penetration rates. Because macroscopic models are able to simulate the traffic within real time, these models are used within model based traffic management systems instead of microscopic models. But macroscopic models cannot model the effect of systems with vehicles using adaptive cruise control, which have an direct effect on microscopic variables. What we are missing now are methods for modelling the impacts of such systems on the traffic flow on the level of macroscopic modelling to be able to consider these impact within traffic management systems. In this contribution an existing macroscopic traffic flow model will be extended with suitable macroscopic terms to be able to consider the impact of these systems on the traffic flow.