A method for establishing a regional sub-region signal coordination model

Abstract

This invention relates to a method for establishing a regional sub-area signal coordination model, belonging to the field of traffic signal control technology. The method includes: establishing an objective function with the maximum green wave bandwidth as the optimization objective; improving the MULTIBAND-96 model based on an asymmetric multi-bandwidth model to obtain a first model; extending the sub-area division model to obtain a second model; establishing a third model based on the sub-area division model, the third model including a signal coordination model between sub-areas; and integrating the objective function, the first model, the second model, and the third model to obtain the final regional sub-area signal coordination model, which solves the problem that existing technologies cannot achieve optimal signal coordination control within a region.

Description

Technical Field

[0001] This invention relates to the field of traffic signal control technology, and in particular to a method for establishing a regional sub-area signal coordination model. Background Technology

[0002] The increasing density of urban road networks has led to a dramatic increase in the number of intersections, resulting in a greater number of arterial road intersections and increasingly complex urban traffic. Addressing congestion in these complex urban road networks requires more than just arterial road coordination and control; it necessitates a regional approach to signal coordination and control.

[0003] As an extension of single-point and trunk line signal control, area signal control can not only solve the problem of traffic flow at other intersections on the trunk line being affected by congestion at a single intersection, but also play a bridging role in signal coordination between sub-areas.

[0004] However, in existing studies, the division of sub-zones is mainly based on parameters such as the distance between adjacent intersections, traffic volume of road segments, queue length, and intersection timing. There is no research on regional sub-zone coordination control that directly uses the green wave width as the optimization target, making it difficult to achieve optimal signal coordination control within the region in a short period of time. Summary of the Invention

[0005] In view of this, it is necessary to provide a method for establishing a regional sub-region signal coordination model to solve the problem that existing technologies cannot achieve optimal signal coordination control within a region.

[0006] To address the above problems, this invention provides a method for establishing a regional sub-region signal coordination model, comprising:

[0007] An objective function is established with the maximum green wave width as the optimization objective.

[0008] The MULTIBAND-96 model is improved based on the asymmetric multi-bandwidth model to obtain the first model;

[0009] The sub-region partitioning model is extended to obtain the second model;

[0010] A third model is established based on the sub-region partitioning model, and the third model includes: a signal coordination model between sub-regions;

[0011] By integrating the objective function, the first model, the second model, and the third model, the final regional sub-region signal coordination model is obtained.

[0012] In one possible implementation, the objective function includes:

[0013]

[0014] in, Indicates the width of the green band; m This indicates the number of roads running east-west, numbered as follows: i ; n This indicates the number of roads running north-south, numbered as follows: j ; ij Indicates the intersecting first i The east-west road and the first j An intersection of two north-south roads; W Indicates the westward direction. E Indicates the direction of travel east. N Indicates the northward direction. S Indicates the direction of travel south; Indicates an intersection ij The time interval between the uplink green wave bandwidth and the center line of the green wave bandwidth at the next intersection. Indicates an intersection ij The green wave bandwidth for the upbound traffic flow to the next intersection.

[0015] In one possible implementation, the improvement of the MULTIBAND-96 model based on the asymmetric multi-bandwidth model to obtain a first model includes:

[0016] Remove the bandwidth constraint of the MULTIBAND-96 model based on the symmetry of the green wave centerline, and establish a new bandwidth constraint.

[0017] In one possible implementation, the new bandwidth constraint includes:

[0018]

[0019]

[0020]

[0021] in, Indicates an intersection ij The green wave bandwidth to the right of the center line of the oncoming traffic at the next intersection Indicates an intersection ij The green wave bandwidth to the right of the centerline of the downhill traffic flow at the next intersection; Indicates an intersection ij The green wave bandwidth to the left of the center line of the oncoming traffic at the next intersection Indicates an intersection ij The green wave bandwidth to the left of the centerline of the downhill traffic flow at the next intersection; This indicates the time it takes for the green wave centerline of the northbound traffic flow at intersection ij to reach the right side of the red light. Indicates an intersection ijThe time it takes for the center line of the green wave to reach the right side of the red light for downbound traffic; Indicates an intersection ij Red light time for northbound traffic. Indicates an intersection ij Red light duration for downhill traffic; Indicates an intersection ij The time required to clear the queue of vehicles in the uphill straight lane. Indicates an intersection ij The time required to clear the queue of vehicles in the downhill straight lane.

[0022] In one possible implementation, the first model includes:

[0023]

[0024]

[0025]

[0026]

[0027]

[0028]

[0029]

[0030] Among them, subscript L Indicates a left turn. T Indicates going straight. R Indicates a right turn. N Indicates the north direction. S Indicates the direction of south. This indicates the number of vehicles in the queue.

[0031] In one possible implementation, the first model further includes:

[0032]

[0033]

[0034]

[0035]

[0036]

[0037] in, Indicates the maximum limit of the common period. Indicates the minimum common period limit, Indicates an intersectionij Green light duration for left turns of oncoming traffic. Indicates an intersection ij Green light duration for left turns of downhill traffic. Indicates an intersection ij Phase difference until the midpoint of the red light at the next intersection. , A set of 0-1 variables, Indicates an intersection ij The maximum speed limit for northbound traffic flowing to the next intersection. Indicates an intersection ij The maximum speed limit for downstream traffic flowing to the next intersection. Indicates an intersection ij The lower limit of the oncoming traffic speed at the next intersection. Indicates an intersection ij The lower limit of the downstream traffic speed at the next intersection. Indicates an intersection ij The upper limit of the speed change of the northbound traffic flow to the next intersection. Indicates an intersection ij The upper limit of the change in downstream traffic speed to the next intersection. Indicates an intersection ij The lower limit of the change in the speed of the upbound traffic flow to the next intersection. Indicates an intersection ij The lower limit of the change in traffic speed in both directions at the next intersection. Represents an integer variable with a value not less than 0, used to constrain the initial phase difference of the signal cycle between adjacent intersections, ensuring that vehicles can pass through the intersection continuously during the green wave period.

[0038] In one possible implementation, the sub-region partitioning model is extended to obtain a second model, which includes:

[0039] The first set of trunk line constraints in the sub-region division model is increased to form several sets of road network constraints, thus obtaining the second model.

[0040] In one possible implementation, the second model includes:

[0041]

[0042]

[0043]

[0044]

[0045]

[0046]

[0047]

[0048]

[0049]

[0050]

[0051]

[0052]

[0053]

[0054]

[0055]

[0056]

[0057]

[0058]

[0059]

[0060]

[0061] in, m This indicates the number of east-west roads within the road network. n This indicates the number of north-south roads within the road network. This indicates the number of sub-regions divided in the east-west direction. This indicates the number of sub-regions divided in the north-south direction. Represents the maximum number of sub-regions within the road network, a 0-1 variable. Indicates road segment ij Whether it is within a sub-region, 0-1 variable Indicates an intersection S ij Whether it is within a sub-region, 0-1 variable Indicates road segment ij Is it a segmentation point? a , b The symbol ] indicates the range of the number of intersections for which signal coordination is required for other road sections. Indicates the optimal signal cycle for the intersection. q Indicates the interference variable. U It is a constant with a value equal to 1000. This indicates the uplink bandwidth at the segment location. This indicates the downlink bandwidth at the segment point.

[0062] In one possible implementation, a third model is established based on the sub-region partitioning model, including:

[0063] Considering signal coordination between sub-regions, the third model is established based on the sub-region partitioning model.

[0064] In one possible implementation, the third model includes:

[0065]

[0066]

[0067]

[0068]

[0069]

[0070]

[0071]

[0072]

[0073]

[0074]

[0075]

[0076] in, Indicates the intersection of any sub-zone within the road network. The signal period, This represents the intersection of adjacent sub-regions of any given sub-region. The signal period, express and The least common multiple of, the least common multiple of in a period Within, the least common multiple of a period Inside, there is indivual The cycle and indivual The cycle, Each period is numbered as k， Each period is numbered as l, Indicates an intersection in the uphill direction. No. k The time difference between the end of the red light cycle and the edge of the green wave. Indicates a crossroads in the down direction No. l The time difference between the end of each red light cycle and the left side of the green wave. express No. k Midpoint of each cycle of red light and No. l Phase difference at the midpoint of the red light cycle, 0-1 variable express No. k Each cycle and No. l Does a green wave exist in each cycle?

[0077] The beneficial effects of this invention are as follows: This invention provides a method for establishing a regional sub-zone signal coordination model. First, using the green wave width as the optimization objective, a regional sub-zone division coordination control model is established. The sub-zone division method is combined with signal coordination control, and optimal regional signal coordination control is achieved through green wave coordination control. Simultaneously, this invention extends the existing sub-zone division model that only considers trunk roads, enabling the final regional sub-zone signal coordination model to optimize the main road's traffic efficiency without affecting intersecting branch roads, thereby improving the overall urban traffic service level and alleviating urban traffic congestion. Furthermore, since MULTBAND-96 only considers signal coordination within sub-zones, it is prone to getting trapped in local optima. Therefore, the first model based on MULTBAND-96 also has the same limitations. This invention adds a third model that considers signal coordination between sub-zones, making the final regional sub-zone signal coordination model more adaptable. It can adapt to road networks with different traffic characteristics, maximize green wave control, and effectively solve the problem that existing technologies struggle to achieve optimal regional signal coordination control. Attached Figure Description

[0078] Figure 1 A flowchart illustrating an embodiment of the method for establishing a regional sub-region signal coordination model provided by the present invention;

[0079] Figure 2 A schematic diagram illustrating the source of vehicles queuing in a straight lane, as provided by this invention;

[0080] Figure 3 A schematic diagram of adjacent sub-regions connected in the east-west direction and adjacent sub-regions connected in the north-south direction, provided for the present invention;

[0081] Figure 4 This is a schematic diagram illustrating the connection between four adjacent sub-regions provided by the present invention. Detailed Implementation

[0082] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which form part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0083] In the description of the embodiments of the present invention, unless otherwise stated, "multiple" means two or more. "And / or" describes the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone.

[0084] The terms "first," "second," etc., used in the embodiments of this invention are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a technical feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature.

[0085] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0086] like Figure 1 As shown, to solve the above problems, the present invention provides a method for establishing a regional sub-region signal coordination model, comprising:

[0087] Step S101: Establish an objective function with the maximum green wave band width as the optimization objective;

[0088] Step S102: Improve the MULTIBAND-96 model based on the asymmetric multi-bandwidth model to obtain the first model;

[0089] Step S103: Extend the sub-region partitioning model to obtain the second model;

[0090] Step S104: Establish a third model based on the sub-region division model. The third model includes: a signal coordination model within a sub-region and a signal coordination model between sub-regions.

[0091] Step S105: Integrate the objective function, the first model, the second model, and the third model to obtain the final regional sub-region signal coordination model.

[0092] It should be noted that the MULTIBAND-96 model refers to the arterial signal coordination model with variable green wave bandwidth; the asymmetric multi-bandwidth model refers to a mathematical model that eliminates the constraint of bandwidth symmetry based on the centerline; the sub-zone division model (MAXBANDLA) is a mathematical model for sub-zone division, consisting of multiple division constraints; and the sub-zone arterial coordination model constrains the signal coordination between two adjacent sub-zone intersections on an arterial line, also consisting of multiple constraints. Conventional sub-zone division and sub-zone arterial coordination models only consider sub-zones on a single arterial line, without addressing the signal coordination issues of road networks containing multiple arterial lines. Therefore, in this embodiment, it is necessary to extend the original sub-zone division and sub-zone arterial coordination models to achieve signal coordination control for road networks containing multiple arterial lines.

[0093] It should be noted that, since the sub-zone division model itself can only divide trunk lines and is not applicable to urban road networks, nor does it consider the signal coordination issues between sub-zones, in this embodiment, when extending the sub-zone division model, the constraints of the original model can be increased from one set to... n Group.

[0094] It should be noted that since the first model is an improvement on the MULTIBAND-96 model, it only considers signal coordination within sub-regions, just like the MULTIBAND-96 model. In practical applications, it is easy to get trapped in local optima. In this embodiment, by using a third model that considers signal coordination between sub-regions, both signal coordination within and between sub-regions is considered. Compared with existing technologies, it is easier to solve for the globally optimal bandwidth.

[0095] It is understood that, in this embodiment, the final regional sub-region signal coordination model includes an objective function, a first model, a second model, and a third model.

[0096] Compared with existing technologies, this invention provides a method for establishing a regional sub-zone signal coordination model. First, it establishes a regional sub-zone division coordination control model with green wave width as the optimization objective. This model combines the sub-zone division method with signal coordination control, achieving optimal regional signal coordination control through green wave coordination control. Furthermore, this invention extends existing sub-zone division models that only consider trunk roads, enabling the final regional sub-zone signal coordination model to optimize main road traffic efficiency without affecting intersecting branch roads, thereby improving the overall urban traffic service level and alleviating urban traffic congestion. In addition, since MULTBAND-96 only considers signal coordination within sub-zones, it is prone to getting trapped in local optima. Therefore, the first model based on MULTBAND-96 also has the same limitations. This invention adds a third model that considers signal coordination between sub-zones, making the final regional sub-zone signal coordination model more adaptable. It can adapt to road networks with different traffic characteristics, maximize green wave control, and effectively solve the problem that existing technologies struggle to achieve optimal regional signal coordination control.

[0097] In one possible implementation, the objective function includes:

[0098] (1)

[0099] In equation (1), Indicates the width of the green band; m This indicates the number of roads running east-west, numbered as follows: i ; n This indicates the number of roads running north-south, numbered as follows: j ; ij Indicates the intersecting first i The east-west road and the first j An intersection of two north-south roads; W Indicates the westward direction. E Indicates the direction of travel east. N Indicates the northward direction. S Indicates the direction of travel south; Indicates an intersection ij The time interval between the uplink green wave bandwidth and the center line of the green wave bandwidth at the next intersection. Indicates an intersection ij The green wave bandwidth for the upbound traffic flow to the next intersection.

[0100] Specifically, let the east-west direction have m Road numbered i , and north-south direction n The two roads intersect, numbered as follows: j Then the intersection can be represented by the numbers of the intersecting roads as follows: The road section number is ijdriving direction W , E , N , S express.

[0101] Bandwidth includes both east-west and north-south directions, using W , E , N , S Representing four directions, the objective function can be expressed as:

[0102] (2)

[0103] Taking an east-west road as an example, let the west entrance be the uphill direction and the east entrance be the downhill direction. Then the objective function for the east-west direction is:

[0104] (3)

[0105] In one possible implementation, step S102 includes:

[0106] Remove the bandwidth constraint of the MULTIBAND-96 model that is based on the symmetry of the green wave centerline, and establish a new bandwidth constraint.

[0107] In one possible implementation, the new bandwidth constraints include:

[0108] (4)

[0109] (5)

[0110] (6)

[0111] In equations (4)-(6), Indicates an intersection ij The green wave bandwidth to the right of the center line of the oncoming traffic at the next intersection Indicates an intersection ij The green wave bandwidth to the right of the centerline of the downhill traffic flow at the next intersection; Indicates an intersection ij The green wave bandwidth to the left of the center line of the oncoming traffic at the next intersection Indicates an intersection ij The green wave bandwidth to the left of the centerline of the downhill traffic flow at the next intersection; Indicates an intersection ij The time it takes for the center line of the green wave to reach the right side of the red light for northbound traffic. Indicates an intersection ij The time it takes for the center line of the green wave to reach the right side of the red light for downbound traffic; Indicates an intersection ijRed light time for northbound traffic. Indicates an intersection ij Red light duration for downhill traffic; Indicates an intersection ij The time required to clear the queue of vehicles in the uphill straight lane. Indicates an intersection ij The time required to clear the queue of vehicles in the downhill straight lane.

[0112] It should be noted that in this embodiment, since the constraint of bandwidth symmetry based on the green wave centerline has been removed, the new constraint added allows different bandwidths to be used for different road segments (between every two intersections), thereby making signal coordination more flexible.

[0113] In one possible implementation, the first model includes:

[0114] (7)

[0115] (8)

[0116] (9)

[0117] (10)

[0118] (11)

[0119] (12)

[0120] (13)

[0121] In equations (10)-(11), the subscripts L Indicates a left turn. T Indicates going straight. R Indicates a right turn. N Indicates the north direction. S Indicates the direction of south. Indicates the number of vehicles in the queue. To save time during startup, For the number of lanes, The saturation flow rate is 0.

[0122] It should be noted that in this embodiment, the bandwidth weight and the target bandwidth ratio in the uplink and downlink directions are similar to those in MULTIBAND-96, as shown in equations (7) and (8) above.

[0123] Specifically, since MULTIBAND requires bandwidth to be strictly symmetrical based on the green wave centerline, we use an asymmetric multibandwidth model (AM-BAND) to improve the model.

[0124] The green wave bandwidth constraint is shown in equations (9)-(11) above.

[0125] like Figure 2 As shown, when the traffic flow does not exceed the saturation flow rate, all vehicles can pass through within the green light time. The queuing vehicles mainly come from vehicles turning at the upstream intersection, resulting in the range of values ​​for the number of queuing vehicles as shown in the above formula (12).

[0126] If the vehicles are cleared at a saturation flow rate after the green light is turned on, then the range of the clearing time can be represented by the above formula (13).

[0127] In one possible implementation, the first model also includes:

[0128] (14)

[0129] (15)

[0130] (16)

[0131] (17)

[0132] (18)

[0133] In equations (14)-(18), Indicates the maximum limit of the common period. Indicates the minimum common period limit, Indicates an intersection ij Green light duration for left turns of oncoming traffic. Indicates an intersection ij Green light duration for left turns of downhill traffic. Indicates an intersection ij Phase difference until the midpoint of the red light at the next intersection. , A set of 0-1 variables, Indicates an intersection ij The maximum speed limit for northbound traffic flowing to the next intersection. Indicates an intersection ij The maximum speed limit for downstream traffic flowing to the next intersection. Indicates an intersection ij The lower limit of the oncoming traffic speed at the next intersection. Indicates an intersection ij The lower limit of the downstream traffic speed at the next intersection. Indicates an intersection ij The upper limit of the speed change of the northbound traffic flow to the next intersection. Indicates an intersection ijThe upper limit of the change in downstream traffic speed to the next intersection. Indicates an intersection ij The lower limit of the change in the speed of the upbound traffic flow to the next intersection. Indicates an intersection ij The lower limit of the change in traffic speed in both directions at the next intersection. Represents an integer variable with a value not less than 0, used to constrain the initial phase difference of the signal cycle between adjacent intersections, ensuring that vehicles can pass through the intersection continuously during the green wave period.

[0134] It is understandable that, in this embodiment, apart from canceling the strict central symmetry of the bandwidth and adding a corresponding constraint, the other constraints of the first model are still consistent with the original MULTIBAND-96.

[0135] In one possible implementation, step S103 includes:

[0136] The first set of trunk line constraints in the sub-region division model is increased to several sets to form road network constraints, resulting in the second model.

[0137] In one possible implementation, the second model includes:

[0138] (19)

[0139] (20)

[0140] (twenty one)

[0141] (twenty two)

[0142] (twenty three)

[0143] (twenty four)

[0144] (25)

[0145] (26)

[0146] (27)

[0147] (28)

[0148] (29)

[0149] (30)

[0150] (31)

[0151] (32)

[0152] (33)

[0153] (34)

[0154] (35)

[0155] (36)

[0156] (37)

[0157] (38)

[0158] in, m This indicates the number of east-west roads within the road network. n This indicates the number of north-south roads within the road network. This indicates the number of sub-regions divided in the east-west direction. This indicates the number of sub-regions divided in the north-south direction. Represents the maximum number of sub-regions within the road network, a 0-1 variable. Indicates road segment ij Whether it is within a sub-region, 0-1 variable Indicates an intersection S ij Whether it is within a sub-region, 0-1 variable Indicates road segment ij Is it a segmentation point? a , b The symbol ] indicates the range of the number of intersections for which signal coordination is required for other road sections. Indicates the optimal signal cycle for the intersection. q Indicates the interference variable. U It is a constant with a value equal to 1000. This indicates the uplink bandwidth at the segment location. This indicates the downlink bandwidth at the segment point.

[0159] Specifically, the number of sub-regions is first constrained. Let's assume east-west roads within the road network... m strip, n A north-south road, with intersection spacing all less than 800m, and no physical dividing points, is defined as follows: The number of sub-zones in the east-west direction is... The north-south direction is A road must have at least two intersections in each of its two ends. The constraint on the number of sub-zones divided by transverse and longitudinal roads is as follows:

[0160] (39)

[0161] By weighing the impact of increasing or decreasing the number of sub-regions on bandwidth and obtaining the sub-region partitioning strategy that minimizes the impact on the total bandwidth, the maximum number of sub-regions within the road network is determined. M It should meet the following requirements:

[0162] (40) Then, constraints are applied to the sub-region division.

[0163] Based on the constraints, we can define the following 0-1 variables.

[0164] Taking an east-west road as an example, define 0-1 variables. Indicates road segment ij Is it in a sub-region? m The inner part is defined as follows:

[0165] (41) Define 0-1 variables Indicates an intersection S ij Is it in a sub-region? m The inner part is defined as follows:

[0166] (42)

[0167] Define 0-1 variables Indicates road segment ij Whether it is a segmentation point, thereby reducing the number of sub-regions. m The resulting increase in the number of constraints is defined as follows:

[0168] (43) If a road has at least two intersections in each of its two ends, meaning that the road segments at the beginning and end should not be used as segmentation points, then:

[0169] (44)

[0170] The number of intersections requiring signal coordination for the remaining road segments should be controlled within the interval [a, b]. In this embodiment, this interval is [3, 5], meaning that there is at most one segmentation point for every 3 road segments and at least two segmentation points for every 5 road segments. Constraints can be established as follows:

[0171] (45)

[0172] At the intersection S ij As the subject of study, an intersection can only be divided into one sub-zone, therefore...

[0173] (46)

[0174] And there are:

[0175] (47)

[0176] (48)

[0177] Linearizing this expression yields:

[0178] (49)

[0179] Constraints are imposed on signal coordination. Based on the traffic flow at each intersection, the optimal signal cycle for that intersection can be calculated using the Webster timing method. Since smaller cycles are generally adjusted to larger cycles and used as common cycles, As the lower limit of the period for each intersection, the maximum period Add interference variables q As the upper limit of the signal period, in this embodiment Taking 10 seconds as an example, the reciprocal of the cycle for each intersection can be expressed as:

[0180] The reciprocal of each intersection signal cycle can be expressed as:

[0181] (50)

[0182] Set sub-region m The reciprocal of the signal period is z m Then we have:

[0183] (51)

[0184] To linearize equation (13), let Then there is

[0185] (52)

[0186] If the road section ij If it is not a segmentation point, the formula remains the same as before; if it is a road segment ij If the segment is a dividing point, then there is no green wave in that segment, and the bandwidth at the dividing point needs to be removed, that is:

[0187] (53)

[0188] make , Then there is

[0189] (54)

[0190] (55)

[0191] (56)

[0192] If the road section ij If it is not a segmentation point, the bandwidth constraint remains unchanged; if it is a road segment ij If the segment is a dividing point, and there are no bandwidth constraints on this segment, then:

[0193] (57)

[0194] Similarly, the cyclic integer constraints for the main line and branches can be obtained:

[0195] (58)

[0196] (59)

[0197] For four adjacent intersections, as long as there are segmentation points, there are no cyclic integer constraints on the road network, and thus we can obtain:

[0198] (60)

[0199] Rewrite the travel time constraints using the same method, and... z use z ij Corresponding substitution:

[0200] (61)

[0201] (62)

[0202] In one possible implementation, step S104 includes:

[0203] Considering signal coordination between sub-regions, a third model is established based on the sub-region partitioning model.

[0204] In one possible implementation, the third model includes:

[0205] (63)

[0206] (64)

[0207] (65)

[0208] (66)

[0209] (67)

[0210] (68)

[0211] (69)

[0212] (70)

[0213] (71)

[0214] (72)

[0215] (73) (74)

[0216] in, Indicates the intersection of any sub-zone within the road network. The signal period, This represents the intersection of adjacent sub-regions of any given sub-region. The signal period, express and The least common multiple of, the least common multiple of in a period Within, the least common multiple of a period Inside, there is indivual The cycle and indivual The cycle, Each period is numbered as k， Each period is numbered as l , Indicates an intersection in the uphill direction. No. k The time difference between the end of the red light cycle and the edge of the green wave. Indicates a crossroads in the down direction No. l The time difference between the end of each red light cycle and the left side of the green wave. express No. k Midpoint of each cycle of red light and No. l Phase difference at the midpoint of the red light cycle, 0-1 variable express No. k Each cycle and No. l Does a green wave exist in each cycle?

[0217] Specifically, existing research focuses on how to divide sub-regions, without considering the signal coordination between sub-regions. Therefore, constraints are established here at the intersections of two adjacent sub-regions to coordinate the signals between them. First, we consider the signal coordination problem at the intersections of two adjacent sub-regions on a trunk line.

[0218] Two intersections are provided and Within adjacent sub-regions 1 and 2, the reciprocal of the period can be obtained as follows: and For ease of calculation, the period is adjusted to a multiple of 5, denoted as . and Let the common multiple of the two periods be . The least common multiple of a period Inside, there is indivual The cycle and indivual The cycle, each cycle is numbered as k and l The objective function can then be expressed as:

[0219] (75)

[0220] (76)

[0221] Defined as No. k Midpoint of each cycle of red light and No. l The phase difference at the midpoint of the red light cycle is introduced into a 0-1 variable. express No. k Each cycle and No. l Whether a green wave exists in a given period is defined as follows:

[0222] (77)

[0223] make ,but:

[0224] (78)

[0225] (79)

[0226] Each bandwidth needs to be controlled within the green light range:

[0227] (80)

[0228] If a green wave exists between two signal periods, then the phase difference must be within one period, that is:

[0229] (81)

[0230] Similarly, disregarding the queue clearing time, the phase difference must satisfy:

[0231] (82)

[0232] The relationship between the other phase differences of the green wave and the first phase difference is as follows:

[0233] (83)

[0234] Based on geometric relationships, for the same number... The following relationship holds:

[0235] (84)

[0236] Next is the constraint of adjacent sub-regions. When the scope of signal coordination expands from the trunk line to the regional road network, the connection between adjacent sub-regions changes from two intersections to two rows of intersections, thus the model will differ from that of the trunk line. After dividing into sub-regions, it is necessary to coordinate the intersections at the boundary between sub-region 1 and sub-region 2. Let two adjacent sub-regions have... n If an intersection needs coordination, there are two connection methods: east-west and north-south. Figure 3 As shown.

[0237] If the adjacent sub-regions are in an east-west direction, then the objective function is:

[0238] (85)

[0239] Similar to the signal coordination between adjacent sub-regions on the trunk line, the constraints will be increased from one set to... n Grouping, we can obtain:

[0240] (86)

[0241] (87)

[0242] (88)

[0243] (89)

[0244] (90)

[0245] If adjacent sub-regions are in a north-south direction, the model constraints are similar to those for east-west directions.

[0246] Cyclic integer constraints between adjacent sub-regions.

[0247] For four adjacent intersections, they can belong to at most four adjacent sub-regions; the cyclic integer constraint will differ depending on the specific circumstances. For example... Figure 4Taking the connection of four adjacent sub-regions as an example:

[0248] Similarly, if the four intersections belong to four different sub-regions, then the cyclic integer constraint is:

[0249] (91)

[0250] The signal coordination model for solving the phase difference between adjacent sub-regions (i.e., the third model of this invention) by combining the above formulas is as follows:

[0251] (92)

[0252] (93)

[0253] (94)

[0254] (95)

[0255] (96)

[0256] (97)

[0257] (98)

[0258] (99)

[0259] (100)

[0260] (101)

[0261] (102) (103)

[0262] The above provides a detailed description of the regional sub-region signal coordination model establishment method provided by the present invention. Specific examples have been used to illustrate the principle and implementation of the present invention. The description of the above embodiments is only for the purpose of helping to understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation and application scope based on the idea of ​​the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A method for establishing a regional sub-area signal coordination model, characterized in that, include: An objective function is established with the maximum green wave width as the optimization objective. The MULTIBAND-96 model is improved based on the asymmetric multi-bandwidth model to obtain the first model, which includes: removing the constraint that the bandwidth of the MULTIBAND-96 model is symmetrical based on the green wave centerline, and establishing a new bandwidth constraint. The sub-region division model is extended to obtain a second model, which includes: adding a set of trunk line constraints in the sub-region division model to several sets of road network constraints to obtain the second model; The third model is established based on the sub-region partitioning model, including: considering signal coordination between sub-regions, and establishing the third model based on the sub-region partitioning model; the third model includes: a signal coordination model between sub-regions. By integrating the objective function, the first model, the second model, and the third model, the final regional sub-region signal coordination model is obtained. The third model includes: in, Indicates the intersection of any sub-zone within the road network. The signal period, This represents the intersection of adjacent sub-regions of any given sub-region. The signal period, express and The least common multiple of, the least common multiple of in a period Within, the least common multiple of a period Inside, there is indivual The cycle and indivual The cycle, Each period is numbered as k， Each period is numbered as l , Indicates an intersection in the uphill direction. No. k The time difference between the end of the red light cycle and the edge of the green wave. Indicates a crossroads in the down direction No. l The time difference between the end of each red light cycle and the left side of the green wave. express No. k Midpoint of each cycle of red light and No. l Phase difference at the midpoint of the red light cycle, 0-1 variable express No. k Each cycle and No. l Does a green wave exist in each cycle? Indicates the width of the green band. m This indicates the number of roads running east-west, numbered as follows: i ; n This indicates the number of roads running north-south, numbered as follows: j ; ij Indicates the intersecting first i The east-west road and the first j The intersection of two north-south roads Indicates an intersection ij The green wave bandwidth for the upbound traffic flow to the next intersection. Indicates an intersection ij Phase difference at the midpoint of the red light at the next intersection.

2. The model building method according to claim 1, characterized in that, The objective function includes: in, Indicates the width of the green band; m This indicates the number of roads running east-west, numbered as follows: i ; n This indicates the number of roads running north-south, numbered as follows: j ; ij Indicates the intersecting first i The east-west road and the first j An intersection of two north-south roads; W Indicates the westward direction. E Indicates the direction of travel east. N Indicates the northward direction. S Indicates the direction of travel south; Indicates an intersection ij The time interval between the uplink green wave bandwidth and the center line of the green wave bandwidth at the next intersection. Indicates an intersection ij The green wave bandwidth for the upbound traffic flow to the next intersection.

3. The model building method according to claim 1, characterized in that, The new bandwidth constraints include: in, Indicates an intersection ij The green wave bandwidth to the right of the center line of the oncoming traffic at the next intersection Indicates an intersection ij The green wave bandwidth to the right of the centerline of the downhill traffic flow at the next intersection; Indicates an intersection ij The green wave bandwidth to the left of the center line of the oncoming traffic at the next intersection Indicates an intersection ij The green wave bandwidth to the left of the centerline of the downhill traffic flow at the next intersection; This indicates the time it takes for the green wave centerline of the northbound traffic flow at intersection ij to reach the right side of the red light. Indicates an intersection ij The time it takes for the center line of the green wave to reach the right side of the red light for downbound traffic; Indicates an intersection ij Red light time for northbound traffic. Indicates an intersection ij Red light duration for downhill traffic; Indicates an intersection ij The time required to clear the queue of vehicles in the uphill straight lane. Indicates an intersection ij The time required to clear the queue of vehicles in the downhill straight lane.

4. The model building method according to claim 3, characterized in that, The first model includes: Among them, subscript L Indicates a left turn. T Indicates going straight. R Indicates a right turn. N Indicates the north direction. S Indicates the direction of south. This indicates the number of vehicles in the queue.

5. The model building method according to claim 4, characterized in that, The first model also includes: in, Indicates the maximum limit of the common period. Indicates the minimum common period limit, Indicates an intersection ij Green light duration for left turns of oncoming traffic. Indicates an intersection ij Green light duration for left turns of downhill traffic. Indicates an intersection ij Phase difference until the midpoint of the red light at the next intersection. , A set of 0-1 variables, Indicates an intersection ij The maximum speed limit for northbound traffic flowing to the next intersection. Indicates an intersection ij The maximum speed limit for downstream traffic flowing to the next intersection. Indicates an intersection ij The lower limit of the oncoming traffic speed at the next intersection. Indicates an intersection ij The lower limit of the downstream traffic speed at the next intersection. Indicates an intersection ij The upper limit of the speed change of the northbound traffic flow to the next intersection. Indicates an intersection ij The upper limit of the change in downstream traffic speed to the next intersection. Indicates an intersection ij The lower limit of the change in the speed of the upbound traffic flow to the next intersection. Indicates an intersection ij The lower limit of the change in traffic speed in both directions at the next intersection. Represents an integer variable with a value not less than 0, used to constrain the initial phase difference of the signal cycle between adjacent intersections, ensuring that vehicles can pass through the intersection continuously during the green wave period.

6. The model building method according to claim 5, characterized in that, The second model includes: in, m This indicates the number of east-west roads within the road network. n This indicates the number of north-south roads within the road network. This indicates the number of sub-regions divided in the east-west direction. This indicates the number of sub-regions divided in the north-south direction. Represents the maximum number of sub-regions within the road network, a 0-1 variable. Indicates road segment ij Whether it is within a sub-region, 0-1 variable Indicates an intersection S ij Whether it is within a sub-region, 0-1 variable Indicates road segment ij Is it a segmentation point? a , b The symbol ] indicates the range of the number of intersections for which signal coordination is required for other road sections. Indicates the optimal signal cycle for the intersection. q Indicates the interference variable. U It is a constant with a value equal to 1000. This indicates the uplink bandwidth at the segment location. This indicates the downlink bandwidth at the segment point.

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