Report on the safety and traffic flow impact of mixed traffic condition

Project manager
Jiali Fu
2021-03-01 - 2021-12-31

The development and application of automated driving technology has shown a great potential in improving traffic safety and traffic efficiency. It will bring tremendous impact and subversive changes to the operating mode of the entire traffic system. It will also be the future direction of the traffic system development. However, since the technology is not yet mature, it can be foreseen that the situation of automated driving mixed with manual driving will last for a long time in the preliminary stage of automated driving. Therefore, VTI initiated the Heterogeneous project together Chalmers, Volvo AB and Volvo Cars to study the coupling relationship between different automated driving behaviours and manual driving behaviour. The Heterogeneous project is under the scope of CTS - The China Sweden Research Centre for Traffic Safety. The aim of this study is to develop methods for evaluating the safety and traffic flow impact when autonomous vehicles mix with manually driven vehicles.

This pre-study intends to report modeling and simulation of heterogenous traffic, which is one of the work packages in the Heterogeneous project. The heterogeneous traffic setup consists of manually driven cars and trucks; they are modeled under the assumption that drivers will adapt their desire time headway depending on the types of his/her own vehicle and the preceding vehicle.  The parameters for the cars and trucks are calibrated based on observations from the HighD dataset. The simulation of heterogeneous traffic is conducted using traffic simulation software SUMO. The work is essential in order to represent the mixed traffic condition correctly, and it is one of the first in this research area to our knowledge. It is a fundamental building block in the Heterogenous project since it provides necessary input to the driving simulators experiment. Thus, it is important to disseminate our knowledge within the community and contribute to the field of traffic safety on an international level.

An article will be submitted to a scientific conference by the end of the pre-study (IEEE Intelligent Transportation Conference).


Short facts

Project title: Report on the safety and traffic flow impact of mixed traffic condition
Project type:
Research area:
Safety performance evaluation

Safer – Vehicle and Traffic Safety Centre

SAFER is the open research arena where researchers and expertise work together to create safe mobility. Our traffic safety approach covers people, vehicles and the infrastructure – and together we contribute to safer road transports and smarter, more sustainable cities.

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