| With the development of science and technology,the technology of the autonomous vehicles has developed rapidly in recent years.At present,many companies have produced the autonomous vehicles which could be driven on the roads in the real world.It can be predicted that the autonomous vehicles will enter every family in the future.But before the full popularity of the autonomous vehicles,it is time for the autonomous vehicles to travel with the human driving vehicles on the road.This is the mixed traffic flow environment.The driving behavior of the autonomous vehicles is different from that of the human driving vehicles especially in the process of the lane changing.On urban roads,the expressways play an important role and hold most traffic flows.Because of the structural characteristics of the weaving area on urban expressway,vehicles must change lane.Therefore,it is necessary to research the traffic flows variation of the weaving area on urban expressway under mixed traffic environment.First,we analyze the lane-changing behavior of vehicle.Combining the characteristics of the autonomous vehicles,we analyze the lane-changing behavior of the autonomous vehicles,especially the decision process.Then based on Game Theory,combining the decision process of the autonomous vehicle lane changing behaviors,we establish the lane-changing strategy model of the autonomous vehicles in three steps,which are the intention to change lane,the conditions for lane changing and the revenue from lane changing.We use Nash equilibrium method to solve the model to get the optimal strategy of lane changing.Then based on Cellular Automata Model,we improved the simulation model of multi-lane traffic flow,and establish the simulation model of the mixed traffic flow which consistent with the characteristics of the weaving area on urban expressway.Finally,we take Southern Expressway in Changchun as an example,simulate it and validate the feasibility of the model.We observe the variation of the rate of flow and the average speed of the weaving area on urban expressway by controlling the ratio of the autonomous vehicles.The result shows that,when the autonomous vehicle exists,the traffic capacity and average speed of the weaving area on urban expressway have been improved.When the ratio of the autonomous vehicles increases from ten percent to ninety percent and the number of the lanes increases from one to four,the traffic capacity and the average speed increases from four percent to twenty-seven percent.But the increasing speed of the traffic capacity and the average speed is becoming slower.When the proportion of the autonomous vehicles increases from ten percent to forty percent,the traffic capacity and the average speed have been significantly improved.And when the proportion of the autonomous vehicles increases from forty percent to ninety percent,the traffic capacity and the average speed have been improved slowly. |
