Construction And Research Of Vehicle Driving Cycle Of City Road

The energy crisis and vehicle exhaust emission problem has been continuously deteriorated along.with the rapid increase of automobile in China. It has become the key problem which is urgent to be solved in the field of traffic environment.Studying and developing Vehicle driving cycles based on the traffic characteristic of our country cities will provide basic data for calculating the vehicle emission and fuel consuming and developing new vehicle types, as well as evaluating the risk investment projects and decision making of traffic control.Learned from the international advanced design methods of vehicle driving cycles, based on the Maximum Likelihood Method and Markov process, the design method of transient driving cycles is studied and developed in this paper.The driving speed of vehicles may be taken on a series of stochastic variables with time and the driving cycles are defined a stochastic process.The driving cycles are researched by the stochastic process of Markov in the paper, the driving cycles are defined different states by maximum likelihood estimation,the transition probabilities of state are requierd,a series of candidate cycles are builded and the representative driving cycle is abstracted from a speed variation curve of a number of measured real driving speeds according to the characteristic parameters.On the basis of a review of state-of-the-art on driving cycles, this thesis first proposed a data collection methodology for developing driving cycles.Then, the research conducted the data collection of vehicles' driving modes in Hefei by a combined use of AM-2600s System and AM-400 System, which further were used to develop an database of driving cycles for classified roads for Hefei.Subsequently, the developed driving cycles were compared with the widely used driving cycles in the world such as ECE15 Using Markov method, a vehicle's driving cycle of Hefei based on 10 parameters from speed data of road tests was synthesized,which may reflect the actual driving condition of Hefei more properly.