Toyota Motor Corporation (TMC), Toyota Motor Engineering & Manufacturing (China) Co., Ltd. (TMEC), Beihang University and CenNavi Technologies Co., Ltd. have agreed to begin a joint verification testing project in which data from the Toyota-developed NETSTREAM (NETwork Simulator for TRaffic Efficiency And Mobility) traffic-flow simulator will be used in practical car-based applications to help alleviate traffic congestion in Beijing, China.
Toyota Central R&D Labs (CRDL) began developing NETSTREAM some 15 years ago, with the intention of predicting the introductory effects of intelligent transportation systems (ITS) for reducing traffic congestion, pollution reduction, and preliminary evaluation of traffic measures. In the early NETSTREAM I, CRDL used a block density method to calculate a wide-area traffic flow at high speed.
In this model, the vehicle’s movement was calculated by a fluid approximation of the traffic flow. CRDL subsequently developed NETSTREAM II, which uses a traffic flow model capable of calculating each vehicle’s movement as is required for ITS introduction. Subsequently, Toyota enhanced the traffic flow model to add acceleration as a condition to improve the calculation of CO2 emissions.
The project will also receive support from the Beijing Municipal Commission of Transport and is scheduled to commence in July.
In the verification tests, vehicles will be guided from congested expressways to uncongested expressways via a newly developed terminal that integrates a portable navigation device (PND) and an on-board electronic toll collection (ETC) device and a smartphone app.
Users will be provided information about required driving times by route, and will also be notified of toll discounts for using uncongested expressways.
With the goal of having the simulator used in city planning, the verification tests will serve to evaluate the simulator’s effect on traffic congestion and the data obtained during the tests will be used to improve its accuracy.
Since July 2011, the four organizations, in their efforts to alleviate traffic congestion, have been using the NETSTREAM traffic-flow simulator in joint research into technologies to predict Beijing traffic conditions. The results from this research will be used in the verification tests to commence in July.
Mori, H.; Kitaoka, H.; Ishida, M.; Asakura, Y. (2010) “Traffic simulator NETSTREAM for evaluation of CO2 emissions,” Intelligent 13th International IEEE Conference on Transportation Systems (ITSC), 2010. doi: 10.1109/ITSC.2010.5625067
Teramoto, E.; Baba, M.; Mori, H.; Asano, Y.; Morita, H. (1997) “NETSTREAM: traffic simulator for evaluating traffic information systems,” IEEE Conference on Intelligent Transportation System, 1997. doi: 10.1109/ITSC.1997.660522