LU502247B1

LU502247B1 - Method for controlling bus travel time at intersection based on vehicle speed guidance

Info

Publication number: LU502247B1
Application number: LU502247A
Authority: LU
Inventors: Yuanwen LAI
Original assignee: Univ Fuzhou
Priority date: 2022-06-10
Filing date: 2022-06-10
Publication date: 2022-12-12

Abstract

The application comprises the following steps: acquiring basic data of intersections between speed guidance information and bus stops; guiding the vehicle speed according to the basic data to obtain an optimized design scheme; setting a comparison scheme based on the optimized design scheme, and performing a simulation experiment; and analyzing the result of the simulation experiment to obtain the best match between the bus travel time and the phase condition of the intersection. The application studies the bus travel time control method based on the analysis of bus running characteristics, and guides the bus speed to adjust the bus travel time on the basis of determining the bus departure time and dwell time, so that the bus travel time is matched with the green light phase of the intersection, and the bus passes through the intersection smoothly to the maximum extent.

Description

DESCRIPTION METHOD FOR CONTROLLING BUS TRAVEL TIME AT INTERSECTION BASED ON VEHICLE SPEED GUIDANCE

TECHNICAL FIELD The application relates to the field of traffic flow control, and in particular to a method for controlling bus travel time at intersection based on vehicle speed guidance.

BACKGROUND Bus operation control mainly includes departure time control, dwell time control and speed guidance control. Departure time is mainly set based on passenger demand and passenger flow change rule. If the departure interval is too short, there may be too many vehicles operating on the line, forming a "line of buses", resulting in idle resources; on the contrary, it may lead to passengers waiting too long, reducing residents’ willingness to choose buses. The reasonable dwell time control can reduce the bus travel time fluctuation caused by the change of the station passenger flow. The dwell time control within the tolerable time range can make the bus pass the intersection by using the green time effectively and reduce the additional parking times brought by the signal control. Reasonable bus departure time interval and bus dwell time control are the premise of effectively realizing speed guidance control. Whether to implement speed guidance control is decided by the relationship between the running state of bus and the phase of intersection, so as to meet the best match between the bus travel time and the phase of intersection.

SUMMARY The application provides a method for controlling bus travel time at intersection based on vehicle speed guidance, the relationship between the running state of the bus and the phase of the intersection is used to decide whether to implement the speed guidance control to meet the best match between the bus travel time and the phase of the intersection.

In order to achieve the above object, the application provides a method for controlling bus travel time at intersection based on vehicle speed guidance, comprising the following steps: Acquiring basic data of intersections between speed guidance information and bus stops; guiding the vehicle speed according to the basic data to obtain an optimized design scheme; setting a comparison scheme based on the optimized design scheme, and performing a simulation experiment; and analyzing the result of the simulation experiment to obtain the best match between the bus travel time and the phase condition of the intersection.

Optionally, the basic data comprises the distance between the position of the vehicle speed guidance information and the stop line of the intersection, the distance between the bus stop and the vehicle speed guidance information, the total number of the bus fleet, the addition and subtraction speed of the bus fleet, the starting time of the green light phase at the intersection, the starting time of the red light phase, the green light time, the red light time and the time when each bus in the bus fleet passes through the vehicle speed guidance information and the driving speed thereof.

Optionally, the vehicle speed guidance includes guiding acceleration and guiding deceleration.

Optionally, the method for guiding acceleration includes: based on the distance = between the vehicle speed guidance information position and the intersection stop line and the

A . al . t; acceleration and the deceleration of the bus fleet, calculating the moment when the i-th bus in the bus fleet reaches the intersection stop line; IL — | VE —v} Ve — V; y 2a th=t,+| 4 —— a Vg And then judging whether the passing time of the tail vehicle in the bus fleet and the intersection green light phase on time 8 and the green light duration g meet the formula th St noe + 8 or not, so as to judge whether bus fleets can all pass the intersection; the

A ; Vg . t; th<t, +g guidance speed is calculated by and under the premise of ensuring that the tail bus of the bus fleet can pass the stop line of the intersection, and Ug = Umin . . 2 ; i Ulm , combining with the speed limit value of urban intersections , the final | | V, …. | guided vehicle speed satisfies the formula: V, = min (Vy, Vim) Optionally, the method for guiding deceleration comprises: tA When the bus fleet arrives at the stop line at the intersection at time “ , judging whether the head bus of the bus fleet can reach the stop line of the intersection after the red light phase is ended according to whether the passing time of the head bus of the bus fleet and the red light

A LL Ly . . ti = ty + r phase starting time and the red light duration 7 meet ; then, judging whether the tail bus of the bus fleet can reach the stop line of the intersection before the end of the green light phase by whether the passing time of the tail bus of the bus fleet, . . Ÿ . . the turning-on time © of the red light phase, the red light duration r and the green light th>t,+r+g duration g meet ; | th =t. +r tà=t+r—+g according to and , calculating the guiding Vg = Umax . vehicle speed under the deceleration condition, and at the same time, combining v V, the speed limit value Im of urban intersection, © satisfying the formula: V, = max (Vmax, Vim) Optionally, the method of the simulation experiment comprises:

Acquiring the basic condition of the simulated intersection; according to the basic situation of the simulated intersection, guiding the vehicle speed to set an optimization scheme; simulating the comparison scheme and the optimization scheme, and obtaining the evaluation indexes of the comparison scheme and the optimization scheme.

Optionally, the evaluation indexes include: average travel time, average delay and average parking times.

Optionally, the method for evaluating the evaluation index includes: placing the starting point of the vehicle travel time detector at the starting point of multi-intersection, placing the ending point of the vehicle travel time detector at the ending point of multi-intersection, and detecting the travel time of vehicles passing through an intersection in the bus non-priority direction; evaluating the average delay statistics results of the control scheme and the optimization scheme.

Compared with the prior art, the application has the following beneficial effects: The application discloses a method for controlling bus travel time at intersection based on vehicle speed guidance, the application studies the bus travel time control method based on the analysis of bus running characteristics, and guides the bus speed to adjust the bus travel time on the basis of determining the bus departure time and dwell time, so that the bus travel time is matched with the green light phase of the intersection, and the bus passes through the intersection smoothly to the maximum extent. The effectiveness of the proposed method is verified by the case intersection selected through a simulation experiment.

BRIEF DESCRIPTION OF THE FIGURES In order to explain the embodiment of the application or the technical scheme in the prior art more clearly, the drawings used in the embodiment will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the application. For ordinary technicians in the field, other drawings can be obtained according to these drawings without paying creative labor.

FIG. 1 is a schematic diagram of intersection location in this embodiment; FIG. 2 is a schematic diagram of VISSIM & COM level in this embodiment; FIG. 3 is a simulation flow in this embodiment; FIG. 4 is a simulation flow in this embodiment; FIG. 5 is a schematic diagram of vehicle speed guidance in this embodiment; FIG. 6 is a schematic diagram of guiding acceleration in this embodiment; FIG. 7 is a schematic diagram of guiding deceleration in this embodiment; FIG. 8 is the derivation process of bus speed guidance control at intersections in this embodiment; FIG. 9 is the statistical result of average travel time in this embodiment, where a is the bus priority direction and b is the bus non-priority direction; FIG. 10 is the statistical result of average delay in this embodiment, where a is the bus priority direction and b is the bus non-priority direction; FIG. 11 is the statistical result of average parking times in this embodiment, where a is the bus priority direction and b is the bus non-priority direction;

DESCRIPTION OF THE APPLICATION The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the drawings in the embodiments of this application. Obviously, the described embodiments are only part of the embodiments of this application, but not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative labor belong to the scope of protection in this application.

In order to make the above objectives, features and advantages of the present application more obvious and understandable, the specific embodiments of the present application will be described in detail below with reference to the accompanying drawings.

Embodiment 1 FIG. 1, FIG. 2, FIG. 3, and FIG. 4 are schematic flow diagrams of the simulation experiment in an intersection bus travel time control method based on vehicle speed guidance in embodiment 1 of the present application, which mainly includes the following steps:

1. Obtaining the basic condition of the simulated intersection.

In embodiment 1 of the present application, for convenience of description, three intersection which are continuous from west to east are sequentially numbere as intersection À, intersection B, and intersection C.

In the urban road network of Fuzhou City, Jinshan Avenue is the main road passing in the east-west direction. The road is in good condition, with the number of lanes on the road section being three lanes in one direction. There is a bus lane on the right side of the road, and the entrance lane at the intersection is designed with widening and channelization. As shown in FIG. 1, the distances between intersections A, B and C are 790m and 520m respectively. The phase sequence and timing parameters of current signal control points are shown in Table 1.

EEE EE Guiding the vehicle speed according to the basic data to obtain an optimized design scheme; as shown in FIG. 5, FIG. 6, FIG. 7 and FIG. 8, flowcharts of vehicle speed guidance described in embodiment 1 of the present application includes guidance acceleration and guidance deceleration. The specific method for guiding and accelerating is as follows: When the driving time of the vehicle satisfies the relationship listed in the formula: t, <i t+ L,/v, Zu Tg This indicates that the intersection is green when the vehicle passes through the speed guidance information and the green light is over when the last vehicle reaches the intersection stop line. At this time, speed guidance information should be set to guide the bus fleet to speed

A up reasonably, assuming the “ is a reasonable guiding speed, the moment % when the vehicle reaches the stop line at the intersection should satisfy the formula: — v A __ U U; 2a tA=t, + A + —— a Us To ensure that all bus fleets can pass the intersection, the passage time of the tail bus in the bus fleet shall meet the requirements shown in the formula: A << By solving the formula, it can be found that under the premise of satisfying the guiding Us = Umin ; ; ; ; ; speed of the bus fleet's tail car passing through the stop line of the intersection, I Ulm . . . the speed limit value of the urban intersection should also be considered. Therefore, the i. Vz final guiding vehicle speed should satisfy the formula: V, = min (Vin, Vım) The specific method for guiding deceleration comprises the following steps: LSh . ; [ When , it means that the green light phase has ended and the red light starts to turn on when the car passes through the speed guidance information. When t<th+Ly/u St +r .

T 17 Lol U1 , it means that the first car can't pass the intersection. At this time, the vehicle speed guidance information should be set to guide the bus fleet to slow down, so that the vehicles can reach the intersection when the green light turns on in the next cycle.

. Us Assuming that is a reasonable guiding speed, the time when the bus fleet reaches the stop line at the intersection 1s the same as the formula. In order to ensure that the bus fleets can pass the intersection, the first bus of the bus fleet should reach the intersection stop line after the red light phase ends, and the last bus of the bus fleet should reach the intersection stop line before the green light phase ends, i.e.

A t = br + r

A tA=t +r+g th =t. +r tà=t+r—+g According to and , calculating the guiding Vg = Umax N vehicle speed under the deceleration condition, and at the same time, combine the v V, speed limit value Im of urban intersection, © satisfies the formula: V, = max (Vmax, Vim) The basic data of the control scheme and the optimization scheme are input into VISSIM simulation software, and the simulation is carried out under the COM application program by using MATLAB, and the evaluation indexes of the control scheme and each optimization scheme are obtained. The specific method is as follows: Step 1: Establishing the road network to be simulated in VISSIM, including the road network, signal lamp, detectors and settings related to vehicle inputs.

Step 2: Establishing a connection with the VISSIM through MATLAB, loading the established simulation road network, and setting related simulation parameters, including simulation time and step size.

Step 3: Carrying out the required relevant simulation through the corresponding settings. In VISSIM & COM, the relevant object values are mainly obtained or modified by obtaining or assigning the values of the object's properties or attributes. The object property assignment and object attribute assignment are performed according to the following rules: Object. set ("property name’, variable);

Object. set ('attvalue', 'attribute name’, variable) FIG. 9, FIG. 10 and FIG. 11 show the method for evaluating the evaluation index in embodiment 1 of this application: the starting point of the vehicle travel time detector 1s placed at the starting point section of multiple intersections, the ending point is placed at the ending point section of multiple intersections, and the travel time of vehicles passing through an intersection is detected in the bus non-priority direction. The average delay statistics of the control scheme and the optimization scheme are evaluated.

The average delay statistics results of the comparison scheme and the optimization scheme are shown in FIG. 9.

(1) As can be seen from FIG. 9, for the average travel time of public transport vehicles in the public transport priority direction, the optimization scheme 1s reduced by 5.5% compared with the control scheme; as for the average travel time of the social vehicles in the public transport priority direction, the optimization scheme is reduced by 0.1% as compared with the control scheme, which shows that the method provided by the application can well improve the traffic efficiency of the public transport vehicles in the public transport priority direction. At the same time, because the bus priority coordination control method provided by the application does not change the phase and the phase sequence of the signal timing scheme of the intersection, the negative influence on social vehicles in the bus priority direction 1s small.

(2) In addition, the optimization scheme is not significant in bus non-priority direction optimization, because the optimization scheme only adds bus priority coordination control on the basis of the control scheme, and this strategy does not affect the bus non-priority direction.

The average delay statistics of the control scheme and the optimization scheme are shown in FIG. 10.

As can be seen from FIG. 10, for the bus priority direction of the optimization scheme, the average delay reduction amplitude of the bus reaches 9.9% and the average delay reduction amplitude reaches 9.4%, which indicates that the method provided by the application can reduce the delay of the bus priority direction. However, the change of social vehicles in index value is not significant, and it has not decreased significantly or increased significantly. Therefore, on the premise of ensuring the basic passing efficiency of social vehicles in the public transportation priority direction, the method provided by the application effectively improves the passing efficiency of public transportation vehicles.

The statistical results of the average parking times of the control scheme and the optimization scheme are shown in FIG. 11.

As can be seen from FIG. 11, for the bus in the priority direction, the optimization amplitude of the optimization scheme reaches 15.2%. This shows that after the implementation of the corresponding optimization strategy, the smoothness of bus driving in the bus priority direction has been improved. For social vehicles, the variation amplitude of the optimization scheme is the smallest. This is because compared with the control scheme, the optimization scheme only increases the bus speed guidance control at the intersection, so the optimization strategy does not have much impact on the traffic efficiency of social vehicles.

The above-mentioned embodiments only describe the preferred mode of the present application, and do not limit the scope of the present application. Without departing from the design spirit of the present application, those of ordinary skill in the art have made various contributions to the technical solutions of the present application. Variations and improvements should fall within the protection scope determined by the claims of the present application.

Claims

1. A method for controlling bus travel time at intersection based on vehicle speed guidance, which is characterized by comprising the following steps: acquiring basic data of intersections between speed guidance information and bus stops; guiding the vehicle speed according to the basic data to obtain an optimized design scheme; setting a comparison scheme based on the optimized design scheme, and performing a simulation experiment; and analyzing the result of the simulation experiment to obtain the best match between the bus travel time and the phase condition of the intersection.

2. The method for controlling bus travel time at intersection based on vehicle speed guidance according to claim 1, which is characterized in that the basic data comprises the distance between the position of the vehicle speed guidance information and the stop line of the intersection, the distance between the bus stop and the vehicle speed guidance information, the total number of the bus fleet, the addition and subtraction speed of the bus fleet, the starting time of the green light phase at the intersection, the starting time of the red light phase, the green light time, the red light time, the time when each bus in the bus fleet passes through the vehicle speed guidance information and the driving speed thereof.

3. The method for controlling bus travel time at intersection based on vehicle speed guidance according to claim 2, which is characterized in that the vehicle speed guidance includes guiding acceleration and guiding deceleration.

4. The method for controlling bus travel time at intersection based on vehicle speed guidance according to claim 3, which is characterized in that the method for guiding acceleration includes: based on the distance | “ between the vehicle speed guidance information position oo | a and the intersection stop line, and based on the acceleration and the deceleration of the bus tA fleet, calculating the moment * when the i-th bus in the bus fleet reaches the intersection stop line; I je] Ve — VU; y 2a th =| 4 te a Vg and then judging whether the passing time of the tail vehicle in the bus fleet and the intersection green light phase on time 8 and the green light duration g meet the formula te St + n Sle FB or not, so as to judge whether bus fleets can all pass the intersection; the

A Vg . ; tA<t, +g guidance speed is calculated by and 8 under the premise of ensuring that the tail bus of the bus fleet can pass the stop line of the intersection, and Ug = Umin . . 2 ; i Ulm , combining with the speed limit value of urban intersections , the final | | V, …. | guided vehicle speed satisfies the formula: V, = min (Vy, Vim)

5. The method for controlling bus travel time at intersection based on vehicle speed guidance according to claim 3, which is characterized in that the method for guiding deceleration comprises: tA when the bus fleet arrives at the stop line at the intersection at time * , judging whether the head bus of the bus fleet can reach the stop line of the intersection after the red light phase is ended according to whether the passing time of the head bus of the bus fleet and the red light

A LL Ly . . ti = ty + r phase starting time and the red light duration 7 meet ; then, judging whether the tail bus of the bus fleet can reach the stop line of the intersection before the end of the green light phase by whether the passing time of the tail bus of the bus fleet, . . Ÿ . . . the turning-on time © of the red light phase, the red light duration r and the green light

A | Zt +tr+g duration g meet ;

A A | H'=t+r t, =t,+tr+g € according to and , calculating the guiding Vg = Umax . vehicle speed under the deceleration condition, and at the same time, combining oo Ulm . . Ve . the speed limit value of urban intersection, satisfies the formula:

6. The method for controlling bus travel time at intersection based on vehicle speed guidance according to claim 1, which is characterized in that the method of the simulation experiment comprises: acquiring the basic condition of the simulated intersection; according to the basic situation of the simulated intersection, guiding the vehicle speed to set an optimization scheme; simulating the comparison scheme and the optimization scheme, and obtaining the evaluation indexes of the comparison scheme and the optimization scheme.

7. The method for controlling bus travel time at intersection based on vehicle speed guidance according to claim 6, which is characterized in that the evaluation indexes include: average travel time, average delay and average parking times.

8. The method for controlling bus travel time at intersection based on vehicle speed guidance according to claim 7, which is characterized in that the method for evaluating the evaluation index comprises: placing the starting point of the vehicle travel time detector at the starting point of multi-intersection, placing the ending point of the vehicle travel time detector at the ending point of multi-intersection, and detecting the travel time of vehicles passing through an intersection in the bus non-priority direction; evaluating the average delay statistics results of the control scheme and the optimization scheme.