WO2021147393A1

WO2021147393A1 - Public transportation interval speed guiding method

Info

Publication number: WO2021147393A1
Application number: PCT/CN2020/121409
Authority: WO
Inventors: 李香迎; 李春明
Original assignee: 爱易成技术(天津)有限公司
Priority date: 2020-01-21
Filing date: 2020-10-16
Publication date: 2021-07-29
Also published as: CN111223300A

Abstract

Disclosed is a public transportation interval speed guiding method, comprising the following steps: step 101, firstly, according to factors such as a bus departure time, and an average speed of a road interval and an average passenger flow at each station in the current period, making a running chart for each shift, wherein the running chart comprises a departure time, an arrival time and a stopping time at each station, and a destination arrival time (S101); step 102, constraining step 101 by means of constraint factors covering five aspects, and according to the constraints, completing a bus time/position-speed standard curve chart (S102); and step 103, after the departure of a vehicle, when a time/position-speed curve is not correctly executed due to any interference with driving operations caused by any factor, performing correction in real time according to a time advance/delay value in the subsequent part (S103). By means of correcting a time/position-speed standard curve chart in real time, driving is carried out according to the induction of a speed curve, such that it is guaranteed, to the greatest extent, that when the departure of a vehicle is on schedule, the vehicle arrives at each midway station and the destination station of a line on schedule.

Description

Method for guiding vehicle speed in public transportation section

Cross-references to related applications

This disclosure claims the priority of a Chinese patent application filed with the Chinese Patent Office on January 21, 2020, with the application number CN202010071197.3 and titled "A method for speed guidance in public transportation sections", the entire content of which is incorporated herein by reference. In the open.

Technical field

The present disclosure relates to the technical field of public transportation systems, and in particular to a speed guidance method for public transportation sections.

Background technique

At present, the bus system can only guarantee the on-time departure, stuck at both ends, and the midway stops are out of control; that is to say, the departure time is controllable, and the terminal arrival time can be measured and assessed, but the midway stops are based on the driver’s experience. Achieved.

There are also patents that can plan the speed curve from station to intersection, and from intersection to station, but this curve is static.

As the most common means of commuting in cities, buses currently control the departure time according to the departure plan, but it is difficult to control the arrival time of each intermediate station and the arrival time of the terminal.

Patent CN201910221264.2, a multi-modal speed optimization method for bus rapid transit, although a certain speed planning is carried out for buses, but there are two shortcomings: 1. The speed-time-position planning of the entire journey cannot be completed; 2. Due to the influence of road conditions, the vehicle deviated from the originally set curve, and there is no way to generate a correction curve in real time.

Summary of the invention

The purpose of the present disclosure is to provide a speed guidance method for public transportation sections. Through the above planning, the time/position-speed curve is corrected in real time. During the driving process, the driver drives according to the guidance of the speed curve to ensure the punctuality of departure to the greatest extent. Arrive at each station and terminal station along the way on time to solve the problems raised in the background art.

In order to achieve the above objectives, the present disclosure provides the following technical solutions:

A vehicle speed guidance method for public transportation sections includes the following steps:

Step 101: First, according to the bus departure time, the average speed of the road section during this period and the average passenger flow of each station, the operation diagram is developed for each shift, including the departure time, the arrival time and stay time of each station, and the destination time;

Step 102: The above steps are constrained by five constraints, and according to the constraints, complete the bus time/position-speed standard curve;

Step 103: After the vehicle departs, due to any interference caused by any factor to the driving operation, the time/position-speed curve is not executed correctly. The subsequent part should be corrected in real time according to the time advance/delay value, and correspond to the current time. The vehicle speed v and the vehicle speed 0 at the arrival time are the endpoints, and the remaining time t and the remaining distance s at the station, the forward acceleration a ₊ , the reverse acceleration a _- and the road section speed limit are constraints, and the time/position is dynamically generated -Speed standard curve graph.

Further, the constraint factors include speed limit requirements at various points on the driving route, vehicle acceleration requirements, economic vehicle speed/vehicle speed and energy consumption curve of the vehicle, average driving speed of each shift/section of the vehicle, and average passenger flow at each station .

Further, the bus time/position-speed standard curve chart has two manifestations:

Take the time-speed running graph as the benchmark, and mark the integral value (position value) at different times; take the position-speed graph as the benchmark, and mark the time value at different positions.

Further, the basis for calculating the speed value in the bus time/position-speed standard curve diagram includes:

The acceleration at the start should be less than or equal to the required acceleration value. You can select multiple acceleration values to accelerate in multiple intervals;

The speed in front of the intersection should be consistent with the predicted position and the induced speed of the intersection in front of the predicted time;

The speed of the section is restricted by the maximum speed limit of the road section;

In the deceleration zone in front of the station, the absolute value of acceleration must be less than or equal to the maximum acceleration requirement, and two or more zones can be selected: natural deceleration zone and forced deceleration zone;

Calculated according to one of the expressions, the speed curve and the area of time must conform to the actual distance of each calculation interval.

Compared with the prior art, the beneficial effects of the present disclosure are: the public transportation section speed guidance method of the present disclosure, the bus draws up a running chart for each shift, and after the vehicle departs, due to any interference caused by any factor to the driving operation, The time/position-speed curve is not executed correctly. The follow-up part needs to be corrected in real time according to the time advance/delay value. Through the above planning, the time/position-speed curve is corrected in real time. The driver is guided by the speed curve during driving. After driving, it is ensured to the greatest extent that after starting on time, it arrives at each station and terminal along the way on time, thereby overcoming the inability to complete the full-distance speed-time-position planning in the prior art and the vehicle deviating from the original due to the influence of road conditions. The set curve does not have the technical defect of the method of generating the correction curve in real time.

Description of the drawings

Figure 1 is a flow chart of the disclosed method for speed guidance of public transportation sections;

Figure 2 is a time/position-speed operation diagram of public transportation vehicles;

Fig. 3 is a coordinate diagram of the calculation method of the time/position-speed dynamic curve of the present disclosure;

Figure 4 is a time/position-speed standard curve diagram of the present disclosure;

Figure 5 is the first time/position-speed dynamic curve of the present disclosure;

Figure 6 is the second time/position-speed dynamic curve of the present disclosure;

FIG. 7 is a schematic diagram of the electronic map guidance of the present disclosure.

Detailed ways

The technical solutions in the embodiments of the present disclosure will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present disclosure. Obviously, the described embodiments are only a part of the embodiments of the present disclosure, rather than all the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present disclosure.

Referring to Figure 1, a vehicle speed guidance method for public transportation sections includes the following steps:

Step 101: First, according to the bus departure time, the average speed of the road section during this period and/or the average passenger flow of each station, formulate an operation diagram for each shift, including the departure time, the arrival time and stay time of each station, and the arrival At the end of the time, the operation diagram is made according to these nodes, and the operation of the bus can be seen more accurately and more intuitively.

The operation diagram formulated above is subject to the following constraints:

1. The speed limit requirements at various points on the driving route, such as the speed limit range and speed limit value of schools, intersections, and/or crosswalks. These speed limit requirements allow buses to be restricted in areas such as schools, intersections and/or crosswalks. Drive fast to ensure road safety.

2. Vehicle acceleration requirements shall be based on the comfort of passengers and no safety hazards, to ensure that standing passengers do not fall and collide with each other while the bus is running, and eliminate safety hazards caused by vehicle acceleration.

3. The economic speed/vehicle speed and energy consumption curve of the vehicle. By drawing this curve, it is possible to know the vehicle speed corresponding to the minimum energy consumption when the vehicle is running.

4. The average driving speed of each shift/section of the vehicle, according to the average driving speed, the time node of arrival at the station can be more accurately planned.

5. The average passenger flow of each station, according to the average passenger flow of each time period, determine the stop time of each shift of each station.

Step 102: The above steps are constrained by five constraints. According to the constraints, the bus time/position-speed standard curve as shown in FIG. 2 can be completed.

Figure 2 has two manifestations:

Manifestation 1: The abscissa time is uniform, so the area between the speed curve and the time axis is equal to the distance; special location points are marked on the abscissa, such as intersection names and/or station names; this form of graph , Can be applied in scenarios where time is the main parameter for automatic driving.

Manifestation 2: The abscissa distance is uniform, and the time information of special location points is marked on the horizontal car, such as the station entry time and exit time; this form of manifestation is more in line with the driver's speed induction when driving.

The calculation basis of the speed value in Figure 2 includes:

1. The acceleration at the start should be less than or equal to the required acceleration value. You can select multiple acceleration values and accelerate according to multiple intervals, which is convenient for calculating the speed value of each interval.

2. The speed in front of the intersection should be consistent with the predicted position and the induced speed of the intersection in front of the predicted time. Refer to patent CN201710285524.3 for calculation of induction speed.

3. The maximum speed before arriving at the station is constrained by the maximum speed limit of the road section. When calculating the speed value, the maximum speed limit of the road should be taken into consideration.

4. In the deceleration zone before arriving at the station, the absolute value of acceleration must be less than or equal to the maximum acceleration requirement. You can choose two or more zones, natural deceleration zone and forced deceleration zone.

5. Calculate according to the expression form 1. The area of the speed curve and time must conform to the actual distance of each calculation interval.

Step 103: Urban roads are not closed, and any driving operation cannot be carried out in an ideal state. It will inevitably be interfered by other vehicles and/or pedestrians, which will affect the pre-planned time/position-speed operation in the above description Figure execution, the time/position-speed curve is not executed correctly due to any interference caused by any factor to the driving operation after the vehicle departs. The subsequent part should be corrected in real time according to the time advance/delay value.

Correction basis for time/position-speed graph:

The current time the vehicle is in advance/delay value of the planned run chart time. If it is necessary to pass through the intersection before arriving at the station, then select the appropriate speed for correction according to the induced speed range after the advance/delay; if this correction cannot guarantee that it will arrive at the front station on time If it still cannot be corrected, the arrival time will be forced to change; the stop time of the station will be corrected; if the stop time of the station still cannot be corrected, it will be changed from the following travel interval (from station to station). Between is a basic driving section) to be corrected.

Through the above planning, the time/position-speed curve is corrected in real time. During the driving, the driver drives according to the guidance of the speed curve to ensure that after the punctual departure, arrive at each station and terminal along the route on time. At the same time, the present disclosure The method can also be used for the control of automatic driving. During automatic driving, the road will also be interfered by various factors. At this time, it is also necessary to calculate the speed of the vehicle and also formulate the vehicle operation diagram. This overcomes the technical defects of the prior art that cannot complete the full-distance speed-time-position planning and that the vehicle deviates from the originally set curve due to the influence of road conditions and does not have a method of generating a correction curve in real time.

3, is known: the current speed v _0, the forward acceleration a _+, a reverse acceleration a _-, the total time T _3, T ₃ to travel from the start, a total distance traveled is S, solve: t _1, t _2, v ₁ and v ₂ , you can draw a complete curve.

Available:

(1) In the S ₁ interval, because the vehicle is accelerating in a positive direction, v ₁ = v ₀ + a ₊ t ₁ (t ₁ is the time when the acceleration ends)

(2) In the S ₂ interval, because the vehicle runs at a constant speed, v ₂ =v ₁

(3) in the section S _3, since the vehicle is in reverse running can be obtained uniform acceleration _{_{_{v 2 = -a - (t 3}}} -t 2)

(4) In the entire driving section,

(5) Available through (1)

(6) Available through (2)(3)

Substitute (5)(6) into (4) to get

v ₁ is two values, select the reasonable value among them, exclude the negative value, the value exceeding the speed range and the small value below the speed range. If the value of v ₁ is in the reasonable range, then calculate the time value t ₁ , t ₂ The values that do not meet the requirements are discarded.

Substituting v ₁ into (5)(6) can solve for t ₁ , t ₂ , the calculation result must satisfy t ₂ ≥ t ₁ , if t ₂ ≤ t ₁ occurs, discard the solution and discard the corresponding speed v ₁ value.

As a general formula, it applies to a wider range of situations:

in:

S is the distance of the interval;

Is the speed at any time i when driving in the section;

t is the time spent in the entire interval;

v ₀ is the initial speed of the vehicle. If starting from a stationary state, the initial speed is 0;

a _i is the acceleration at any time i when driving in the section.

As shown in Figure 4, the standard curve is a standard curve directly made according to the vehicle running diagram. Compared with the above figure, v ₀ =0km/h, other calculation methods are the same. The time/position-speed dynamic curve is the vehicle in the running process. , Due to the failure to drive according to the standard curve, it is necessary to constantly calculate and correct the untraveled section according to the five constraint conditions.

Two manifestations of time/position-speed graph:

According to the results we can get an array _{_{(t i, v i, S}} i) that is the driving speed of v _i t _i and the position (distance from the starting point value) S _i at each moment.

Manifestation 1:

Using time as the abscissa and speed as the ordinate, mark the position at a special point on the time axis, namely the time/position-speed dynamic curve 1, as shown in Figure 5.

Manifestation two:

Take the position (distance value from the starting point) as the abscissa, and the speed as the ordinate, and mark the time at the special point of the vehicle at the position, that is, the time/position-speed dynamic curve two, as shown in Figure 6.

According to the time/position-speed dynamic curve to guide the driving behavior of the bus, the following methods can also be used to guide on the electronic map, as shown in Figure 7. The circle represents the position and speed on the electronic map according to the time/position-speed standard curve, and XX _km/h represents the speed and position of the vehicle after deviation due to various factors in actual operation.

The first line in Figure 7 is the overlap of the two icons, that is, the vehicle is driving completely on the standard curve without deviation.

Lines 2 and 3 indicate that the vehicle speed is slower than the standard curve speed, causing a negative deviation. There is a direction arrow between the two circles, indicating that the vehicle should accelerate and chase the standard circle on the electronic map until they coincide; the two circles coincide , It means that the bus can arrive at the bus station on time.

Lines 4 and 5 indicate that the vehicle is faster than the standard curve, causing a positive deviation. There is a direction arrow between the two circles, indicating that the vehicle should slow down. Wait for the standard circle on the electronic map until the standard circle coincides; if the two circles coincide, it means The bus can arrive at the bus station on time.

To sum up: in the public transportation section speed guidance method of the present disclosure, the bus draws up a running chart for each shift. After the vehicle departs, due to any interference caused by any factor to the driving operation, the time/position-speed curve is not correct Execution, the follow-up part should be corrected in real time according to the advance/delay value of the time. Through the above planning, the time/position-speed curve will be corrected in real time. During the driving process, the driver will drive according to the guidance of the speed curve to ensure punctual departure to the greatest extent After that, it arrived at each station and terminal along the route on time, thus overcoming the inability to complete the full-distance speed-time-position planning in the prior art and the vehicle deviated from the original set curve due to road conditions, and no real-time correction was generated. The technical flaws of the curve method.

The above are only preferred specific implementations of the present disclosure, but the protection scope of the present disclosure is not limited to this. Anyone familiar with the technical field within the technical scope disclosed in the present disclosure, according to the technical solutions of the present disclosure The equivalent replacement or change of the inventive concept thereof shall be covered within the protection scope of the present disclosure.

Claims

A vehicle speed guidance method for a public transportation section, which is characterized in that it comprises the following steps:

Step 101: First, according to the bus departure time, the average speed of the road section during this period and the average passenger flow of each station, the operation diagram is developed for each shift, including the departure time, the arrival time and stay time of each station, and the destination time;

Step 102: The above steps are constrained by five constraints, and according to the constraints, complete the bus time/position-speed standard curve;

Step 103: After the vehicle departs, due to any interference caused by any factor to the driving operation, the time/position-speed curve is not executed correctly. The subsequent part should be corrected in real time according to the time advance/delay value, and correspond to the current time. The vehicle speed v and the vehicle speed 0 at the arrival time are the endpoints, and the remaining time t and the remaining distance s at the station, the forward acceleration a + , the reverse acceleration a - and the road section speed limit are constraints, and the time/position is dynamically generated -Speed standard curve graph.
The vehicle speed guidance method for a public transportation section according to claim 1, wherein the constraint factors include speed limit requirements at various points on the driving route, vehicle acceleration requirements, economic vehicle speed/vehicle speed and energy consumption curve of the vehicle, The average speed of each shift/section of the vehicle and the average passenger flow of each station.
The method for guiding speed in a public transportation section according to claim 1, wherein the time/position-speed standard curve diagram of public transportation vehicles has two manifestations:

Take the time-speed running graph as the benchmark, and mark the integral value (position value) at different times; take the position-speed graph as the benchmark, and mark the time value at different positions.
The method for guiding speed in a public transportation section according to claim 1, wherein the basis for calculating the speed value in the time/position-speed standard curve of the public transport vehicle comprises:

The acceleration at the start should be less than or equal to the required acceleration value. You can select multiple acceleration values to accelerate in multiple intervals;

The speed in front of the intersection should be consistent with the predicted position and the induced speed of the intersection in front of the predicted time;

The speed of the section is restricted by the maximum speed limit of the road section;

In the deceleration zone in front of the station, the absolute value of acceleration must be less than or equal to the maximum acceleration requirement, and two or more zones can be selected: natural deceleration zone and forced deceleration zone;

Calculated according to one of the expressions, the speed curve and the area of time must conform to the actual distance of each calculation interval.