阅读说明：本技术 一种公共交通信号优先的相位切换方法 (Phase switching method for priority of public traffic signals ) 是由 张京华 李冰 吴羡 曹从咏 于 2020-12-07 设计创作，主要内容包括：本发明公开了一种公共交通信号优先的相位切换方法,包括：基于GPS检测公交车辆位置,预测公交车辆到达交叉口停车线的时间；通过设置在各个车道上的车辆检测器检测到各个相位的到达车辆数,计算出各个相位的车辆排队长度；根据公交车到达时间与车辆排队长度对信号控制方案进行调整；根据公交相位执行与否,为调整后的信号控制方案选取相应相位切换方法。本发明对信号控制方案进行了调整,使其更好地满足绿灯时间的约束条件,有效提高了通行效率。(The invention discloses a method for switching the priority phase of public traffic signals, which comprises the following steps: the method comprises the steps of detecting the position of a bus based on a GPS, and predicting the time when the bus reaches a stop line at an intersection; detecting the number of arriving vehicles in each phase by a vehicle detector arranged on each lane, and calculating the vehicle queuing length of each phase; adjusting the signal control scheme according to the arrival time of the bus and the queuing length of the bus; and selecting a corresponding phase switching method for the adjusted signal control scheme according to the execution of the bus phase. The invention adjusts the signal control scheme, so that the signal control scheme can better meet the constraint condition of green light time, and the traffic efficiency is effectively improved.)

1. A method for switching the priority phase of public traffic signals is characterized by comprising the following specific steps:

the method comprises the following steps that 1, the position of a bus is detected based on a GPS, and the time of the bus reaching a stop line at an intersection is predicted;

step 2, detecting the number of arriving vehicles in each phase through vehicle detectors arranged on each lane, and calculating the vehicle queuing length of each phase;

step 3, adjusting a signal control scheme according to the arrival time of the bus and the queuing length of the bus;

and 4, selecting a corresponding phase switching method for the adjusted signal control scheme according to the execution condition of the bus phase.

2. The method for switching the priority phases of the public traffic signals according to claim 1, wherein the specific method for detecting the position of the bus based on the GPS in the step 1 is as follows:

step 1-1, creating a vehicle primitive dynamic temporary layer in a computer;

step 1-2, reading the current position information of the vehicle;

step 1-3, data matching, namely converting the current position information of the vehicle into a relative position in a map by using a map matching algorithm;

step 1-4, displaying the vehicle, if the vehicle is on-line for the first time, creating a vehicle primitive, adding the vehicle primitive into a layer, and storing a number for generating a new primitive into a database; and if not, updating the current position of the vehicle and the vehicle running information in the map layer.

3. The method of claim 1, wherein the step 3 of adjusting the signal control scheme comprises:

step 3-1, the time that the jth vehicle at the 1 st phase r direction of the No. i intersection enters the road section in the statistical time interval isThe method comprises the following steps that the xth vehicle is the first vehicle of an upstream key induction fleet, signal scheme adjustment is carried out by taking the induction traffic flow to form a saturated fleet as a target, and the time of the jth vehicle passing through the intersection i after induction is as follows:

in the formula (I), the compound is shown in the specification,for the time when the j-th vehicle in the p-th phase r direction of the k-th cycle of the intersection i is expected to pass through the intersection,the number of vehicles staying for the upper cycle in the p-th phase r direction of the k-th cycle of the intersection i,for vehicles at the p phase r direction of the k period at the i-th intersectionThe maximum induced speed of the vehicle is,the length of the p phase r direction road section in the k period of the intersection i,the number of released lanes and the initial wave propagation speed of queued vehicles in the p phase r direction of the intersection i are respectively,the traffic flow saturation headway in the direction of the p phase r of the intersection I is shown, and delta is the starting loss time;

step 3-2, when j is larger than or equal to x and the time that the j-th vehicle passes through the intersection i is met:

and is

The ending time of the 1 st phase green light of the k period of the intersection i isWherein t is₀Is unit green light duration, s;

step 3-3, takingThe 1 st phase duration adjustment is scaled back among the other three phases,rounding according to the calculation result, satisfying the green light time constraint condition, and keeping the period duration unchanged, that is

In the formula (I), the compound is shown in the specification,and respectively adjusting the green light time before and after the adjustment of the p phase signal scheme of the k period of the i-th intersection.

4. The method as claimed in claim 1, wherein the step 4 selects a corresponding phase switching method for the adjusted signal control scheme according to whether the bus phase is executed or not, and the method comprises:

the phase sequence of the initial signal scheme is first phase-second phase-third phase-fourth phase-first phase-second phase-third phase-fourth phase;

if the bus phase in the period is not executed, the fourth phase is a bus running phase, and a bus priority request is received in the second phase, a phase sequence adjustment strategy is adopted, the phase release sequence is a first phase, a second phase, a fourth phase, a third phase, a first phase, a second phase, a third phase and a fourth phase, the initial signal control scheme is recovered when the period is finished, and the second period still runs according to the initial scheme;

if the bus phase is executed in the period, the first phase is the bus running phase and the bus priority request is received at the third phase, after a phase sequence adjustment strategy is adopted, the phase release sequence is the first phase, the second phase, the third phase, the first phase, the fourth phase, the second phase, the third phase and the fourth phase; adopting a special phase insertion strategy, wherein the phase release sequence is a first phase, a second phase, a third phase, a first phase, a fourth phase, a first phase, a second phase, a third phase and a fourth phase; with the phase hopping strategy, the first phase-second phase-third phase-fourth phase is operated.

Technical Field

The invention belongs to a traffic signal phase switching technology, and particularly relates to a phase switching method for priority of public traffic signals.

Background

At present, the prior control of public traffic signals in most cities has the following problems: the unified, standard and easily-recognized bus special signal lamps are lacked, so that social vehicles and bus vehicles are difficult to control in a differentiated mode; the phase setting and the time matching are not flexible and accurate enough, and most of the existing public traffic signal priority methods apply simple control self-strategies and lack comprehensive consideration on traffic flow passing benefits of road intersections. Therefore, the improvement of the global benefit is difficult to be brought, and the balance of the benefits of all parties is difficult to be ensured simultaneously.

Disclosure of Invention

The invention aims to provide a method for switching the priority phase of public traffic signals.

The technical scheme for realizing the purpose of the invention is as follows: a method for switching the priority phase of public traffic signals includes the following steps:

the method comprises the following steps that 1, the position of a bus is detected based on a GPS, and the time when the bus reaches a stop line at an intersection is predicted;

step 2, detecting the number of arriving vehicles in each phase through vehicle detectors arranged on each lane, and calculating the vehicle queuing length of each phase;

step 3, adjusting a signal control scheme according to the arrival time of the bus and the queuing length of the bus;

and 4, selecting a corresponding phase switching method for the adjusted signal control scheme according to the execution condition of the bus phase.

Preferably, the specific method for detecting the position of the bus based on the GPS in the step 1 is as follows:

step 1-1, creating a vehicle primitive dynamic temporary layer in a computer;

step 1-2, reading the current position information of the vehicle;

step 1-3, data matching, namely converting the current position information of the vehicle into a relative position in a map by using a map matching algorithm;

step 1-4, vehicle display, wherein if the vehicle is on-line for the first time, a vehicle primitive is created and added into a layer, and meanwhile, the number of a generated new primitive is stored in a database; and if not, updating the current position of the vehicle and the vehicle running information in the map layer.

Preferably, the specific method for adjusting the signal control scheme in step 3 is as follows:

step 3-1,The time that the j-th vehicle at the 1 st phase r direction of the i-th intersection enters the road section in the statistical time interval isThe method comprises the following steps that the xth vehicle is the first vehicle of an upstream key induction fleet, signal scheme adjustment is carried out by taking a saturated fleet formed by induced traffic as a target, and the time of the jth vehicle passing through the intersection i after induction is as follows:

in the formula (I), the compound is shown in the specification,the time when the j-th vehicle in the p-th phase r direction of the k-th period of the intersection i is expected to pass through the intersection,the number of vehicles staying for the upper cycle in the p-th phase r direction of the k-th cycle of the intersection i,the maximum induction speed of the vehicle in the p phase r direction of the k period of the intersection i,the length of the p phase r direction road section in the k period of the intersection i,the number of released lanes and the initial wave propagation speed of queued vehicles in the p phase r direction of the intersection i are respectively,the traffic flow saturation headway in the direction of the p phase r of the intersection I is shown, and delta is the starting loss time;

step 3-2, when j is larger than or equal to x and the time that the j-th vehicle passes through the intersection i is met:

and is

The ending time of the 1 st phase green light of the k period of the intersection i isWherein t is₀Is unit green light duration, s;

step 3-3, takingThe 1 st phase duration adjustment is scaled back among the other three phases,rounding according to the calculation result, satisfying the green light time constraint condition, and keeping the period duration unchanged, that is

In the formula (I), the compound is shown in the specification,and the green time lengths before and after the adjustment of the p phase signal scheme of the k period of the i-th intersection are respectively set.

Preferably, the specific method of selecting the corresponding phase switching method for the adjusted signal control scheme according to whether the bus phase is executed or not in step 4 is as follows:

the phase sequence of the initial signal scheme is first phase-second phase-third phase-fourth phase-first phase-second phase-third phase-fourth phase;

if the bus phase in the period is not executed, the fourth phase is a bus running phase, and a bus priority request is received in the second phase, a phase sequence adjustment strategy is adopted, the phase release sequence is a first phase, a second phase, a fourth phase, a third phase, a first phase, a second phase, a third phase and a fourth phase, the initial signal control scheme is recovered when the period is finished, and the second period still runs according to the initial scheme;

if the bus phase is executed in the period, the first phase is the bus running phase and the bus priority request is received at the third phase, after a phase sequence adjustment strategy is adopted, the phase release sequence is the first phase, the second phase, the third phase, the first phase, the fourth phase, the second phase, the third phase and the fourth phase; adopting a special phase insertion strategy, wherein the phase release sequence is a first phase, a second phase, a third phase, a first phase, a fourth phase, a first phase, a second phase, a third phase and a fourth phase; with the phase hopping strategy, the first phase-second phase-third phase-fourth phase is operated.

Compared with the prior art, the invention has the following remarkable advantages: 1) the invention utilizes GPS to detect the position information of the bus, the technical condition is mature, and the application cost is low; 2) the invention adjusts the signal control scheme, so that the signal control scheme can better meet the constraint condition of green light time, and the traffic efficiency is effectively improved; 3) the invention fully considers various conditions of the bus arriving at the intersection, and selects the signal phase switching method according to different conditions, thereby having high utilization rate.

The present invention is described in further detail below with reference to the attached drawings.

Drawings

Fig. 1 is a GPS positioning flowchart.

Fig. 2 is a schematic phase diagram.

Fig. 3 is a flow chart of a phase switching method.

Detailed Description

As shown in fig. 1 to 3, a method for switching a priority phase of a public traffic signal includes the following steps:

the method comprises the following steps of 1, detecting the position of the bus based on a GPS, and predicting the time when the bus reaches a stop line at an intersection, wherein the specific method for detecting the position of the bus based on the GPS comprises the following steps:

step 1-1, creating a vehicle primitive dynamic temporary layer;

step 1-2, reading the current position information of the vehicle: the data such as the three-dimensional coordinates of the vehicle are recorded by a GPS receiving device at certain intervals, and the data are transmitted to a vehicle-mounted computer, and then the vehicle data are transmitted to a data processing center by a communication board and are stored in a database server; finally, combining the data with a Geographic Information System (GIS), and processing and analyzing the data by a server to obtain vehicle information;

step 1-3, data matching, namely converting the current position information of the vehicle into a relative position in a map by using a map matching algorithm;

and 1-4, displaying the vehicle. If the vehicle is on-line for the first time, creating a vehicle primitive, adding the vehicle primitive into the map layer, and simultaneously storing the number of the generated new primitive into a database for distinguishing other vehicle primitives; and if not, updating the current position of the vehicle and the vehicle running information in the map layer.

Step 2, detecting the number of arriving vehicles in each phase through vehicle detectors arranged on each lane, and calculating the vehicle queuing length of each phase, wherein the method specifically comprises the following steps:

a group of vehicle detectors are arranged on straight lanes and left-turn lanes of each phase, and the arrival of traffic flow and the queuing length of vehicles on each lane are detected in real time;

step 3, adjusting the signal control scheme, wherein the specific method comprises the following steps:

step 3-1, setting a first phase of east-west straight behavior, converting east-west left into a second phase, converting north-south straight behavior into a third phase, and converting north-south left into a fourth phase;

the time that the j-th vehicle at the 1 st phase r direction of the i-th intersection enters the road section in the statistical time interval isThe x-th vehicle is the first vehicle of the upstream critical induced fleet, so that the phase green time can be fully utilized, and signal scheme adjustment is carried out by taking the aim of inducing traffic flow to form a saturated fleet. Carry out luringThe time for leading the jth vehicle to pass through the intersection i is as follows:

in the formula (I), the compound is shown in the specification,the time s for the j-th vehicle in the p-th phase r direction in the k period of the intersection i to expect to pass through the intersection is set;

the number of retained vehicles for the upper cycle in the p-th phase r direction of the k-th cycle at the intersection i, pcu;

the maximum induction speed of the vehicle in the direction of the p phase r at the k period of the intersection i is km/h;

the length m of a section in the direction of the p phase r at the k period of the intersection i;

respectively the number of released lanes and the initial wave propagation speed of queued vehicles in the direction of the p phase r at the intersection i, km/h;

the traffic flow saturation headway in the direction of the p phase r of the intersection i is s/pcu;

δ is the start-up loss time, s.

Step 3-2, when j is larger than or equal to x and the time that the j-th vehicle passes through the intersection i is met:

and isThe 1 st phase green light ending time of the k period of the intersection i is set to beWherein t is₀Is the unit green light duration, s.

Step 3-3, comprehensively considering the phase bidirectional key traffic flow to form a saturated fleet, and takingIn order to ensure that the time length C of the common period is kept unchanged, the 1 st phase time length adjustment value is adjusted back in other three phases according to the proportion,rounding according to the calculation result, satisfying the green light time constraint condition, and keeping the period duration unchanged, that is

In the formulaAnd respectively adjusting the green light time before and after the adjustment of the p phase signal scheme of the k period of the i-th intersection.

And 4, selecting a corresponding phase switching method for the adjusted signal control scheme according to the detection result, wherein the specific method comprises the following steps:

the phase sequence of the initial signal scheme is first phase-second phase-third phase-fourth phase-first phase-second phase-third phase-fourth phase;

if the bus phase in the period is not executed, the fourth phase is a bus running phase, and the system receives a bus priority request in the second phase, a phase sequence adjustment strategy is adopted, the phase release sequence is a first phase, a second phase, a fourth phase, a third phase, a first phase, a second phase, a third phase and a fourth phase, the initial signal control scheme is recovered when the period is ended, and the second period still runs according to the initial scheme.

If the bus phase is executed in the period, the first phase is the bus running phase and the system receives a bus priority request at the third phase, after a phase sequence adjustment strategy is adopted, the phase release sequence is the first phase, the second phase, the third phase, the first phase, the fourth phase, the second phase, the third phase and the fourth phase; adopting a special phase insertion strategy, wherein the phase release sequence is a first phase, a second phase, a third phase, a first phase, a fourth phase, a first phase, a second phase, a third phase and a fourth phase; with the phase hopping strategy, the system operates the first phase-second phase-third phase-fourth phase.