Petri Nets And Heuristic Algorithm Based Conflict-free Vehicle Scheduling At Unsignalized Intersection

With the increasingly busy road traffic,traffic safety and traffic efficiency at intersections have become common concerns.Therefore,an advanced intersection vehicle scheduling strategy becomes particularly important.The intersection supervision and control system plays the role of supervising and dispatching vehicles arriving at the intersection.It can not only ensure that the vehicles arriving at the intersection can pass without collision,but also avoid congestion and improve the efficiency of vehicle traffic at the intersection.However,the existing supervision and control system for intersections is implemented based on the traffic signal control system,which is a passive dispatching strategy,which cannot adapt to the traffic flow in a timely manner.In view of the above problems,this paper proposes an intersection vehicle scheduling strategy.First,the Petri net supervised control theory is used to avoid vehicle collisions and deadlocks at intersections.In order to improve the traffic efficiency,a singleintersection vehicle scheduling strategy and a multi-intersection vehicle scheduling strategy are proposed.The specific research content is as follows:1.Discretize the intersection and construct a two-way two-lane Petri net model and a twoway four-lane Petri net model.2.Using the Petri net supervised control theory minimum change coverage method,set up an intersection monitor to solve the problem of intersection conflict and deadlock.Finally,the model is simulated to verify the effectiveness of the monitor.3.Under the control of the monitor,the vehicle can safely pass through the intersection,but it only serves as a safety monitoring function.To solve this problem,this paper proposes a priority-based genetic algorithm to solve the optimal vehicle scheduling sequence.There is a one-to-one correspondence between the vehicle scheduling sequence and the transitions in the Petri net model.Finally,the Petri net model is used to verify whether there is a deadlock problem in the vehicle scheduling sequence.4.This paper proposes a priority based multi intersection vehicle scheduling strategy,which solves the vehicle scheduling problem when there is a main road and a branch road,and the main road through vehicles do not stop between multiple intersections.