A signal priority control method based on no bus lane condition

Abstract

The application provides a signal priority control method based on a condition without bus lane, first, a target vehicle delay contour line auxiliary line is established, target vehicle delay and its probability density function are calculated; second, the maximum queuing length in front of the target vehicle is determined; then, the target vehicle intersection delay expectation and variance are calculated based on the vehicle delay and the corresponding probability density function in the effective range; finally, appropriate signal control parameters are selected, a signal control scheme is formed in the target cycle, the target function value under each scheme is calculated, and the signal control scheme making the target function value minimum is selected for implementation. The signal priority control method based on the condition without bus lane provided by the application makes up for the deficiencies in the prior art, such as based on the bus lane, not considering the intersection queuing, and regarding the vehicle speed as a constant, and is more in line with the actual traffic situation, and the reliability and implementability of the control method are ensured through the consideration of the randomness of the vehicle running process.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of intelligent traffic signal control, in particular to a signal priority control method based on no bus lane condition. BACKGROUND

[0002] As a kind of traffic signal control technology, signal priority control can adjust signal timing scheme according to the arrival of target priority vehicle (target vehicle), and reduce the delay of target vehicle at signalized intersection. Therefore, this technology is widely used to reduce the delay of some vehicles at intersection, such as buses, emergency vehicles, etc., but the signal priority strategy currently adopted is mostly traditional passive priority strategy. This signal priority control strategy is more effective for intersections on road sections with bus lanes, because vehicles driving on bus lanes are basically not affected by random factors on the road, and can reach the intersection within the planned priority time, but this signal priority control strategy cannot cope with dynamic changes in traffic conditions, and for intersections on road sections without bus lanes, which are greatly affected by random factors, this strategy not only may fail, but also affects the traffic efficiency of the intersection.

[0003] Due to land use restrictions, there are fewer bus lanes, and passive signal priority control strategy is difficult to provide effective priority for buses and emergency vehicles. Therefore, solving the problem of vehicle priority under the condition of no bus lane is of great significance to improve the level of public service and emergency response. SUMMARY

[0004] The purpose of the present application is to provide a signal priority control method based on no bus lane condition, which takes into account the randomness of intersection queuing and the randomness of target vehicle speed, and provides accurate signal priority control for target vehicles under no bus lane condition.

[0005] In order to achieve the above purpose, the present application provides a signal priority control method based on no bus lane condition, comprising the following steps:

[0006] S1: data acquisition, investigate the traffic information of intersection, the traffic information includes traffic flow arrival law, distribution law of target vehicle travel speed, dissipation speed of queuing traffic flow, signal timing scheme, pedestrian crossing distance, to obtain the input parameters of the model;

[0007] S2: setting vehicle detector upstream of the intersection, the distance between the detector and the intersection is greater than the maximum queuing length, and the arrival time of target vehicle is obtained through the detector;

[0008] S3: Based on the arrival time of the target vehicle detected by the detector, the delay condition of the target vehicle arriving at the intersection is predicted, and the delay contour of the target vehicle is established to calculate the time and position of the target vehicle joining the queue;

[0009] S4: The queue dissipation wave parallel to the delay contour is established, and the time difference between the queue dissipation wave and the target vehicle delay contour at the same position is calculated to obtain the delay duration t of the target vehicle at the intersection d , that is, the delay duration t of the target vehicle at the intersection d The expression of the corresponding probability density function f(t d ) is:

[0010] f(t d ) = P(k(t d ))·g(v(t d ))

[0011] f(t d ): The corresponding probability density when the target vehicle has a delay duration t d at the intersection;

[0012] P(k(t d )): The probability that the number of queued vehicles at the intersection is k when the target vehicle has a delay duration t d at the intersection;

[0013] k(t d ): The corresponding number of queued vehicles at the intersection when the target vehicle trajectory intersects with the delay contour;

[0014] g(v(t d )): The probability density of the target vehicle travel speed v when the target vehicle has a delay duration t d at the intersection;

[0015] v(t d ): The corresponding target vehicle travel speed when the target vehicle trajectory intersects with the delay contour;

[0016] And the relationship between k(t d ) and v(t d ) is:

[0017]

[0018] t re : The end time of the red light of the target signal period;

[0019] t d : The delay duration of the target vehicle at the intersection;

[0020] l car : average length of vehicles in queue;

[0021] w: wave speed of queue dissipation;

[0022] t0: current time of target vehicle reaching detector;

[0023] l0: distance between intersection and detector;

[0024] S5: determining maximum queue length of vehicles in front of target vehicle;

[0025] S5.1: if signal state at current time t0 is green, then calculate time interval t between last red start time and current time;

[0026] S5.2: calculate probability accumulation of vehicles in queue k in time t, expressed as:

[0027]

[0028] S5.3: compare maximum queue length k·l at current time with position to which queue dissipates, i.e. when k·l car is greater than lcar

[0029] if k·l car is greater than lcar

[0030] if k·l car is smaller, then queue has completely dissipated at current time, and maximum queue length in a cycle is lcar max

[0031] S6.1: generate multiple different signal timing schemes according to display time length of green and red in adjustment, i.e. realize priority control by changing signal timing scheme of target cycle;

[0032] Value range of each signal priority control parameter in signal timing scheme is as follows:

[0033] min i max

[0034] min i max

[0035]

[0036] ​​​​​​​​g i : variable green time of target signal cycle i;

[0037] g max : maximum value of variable green time of target vehicle approach direction signal phase;

[0038] g min : minimum value of variable green time of target vehicle approach direction signal phase;

[0039] r i : variable red time of target signal cycle i;

[0040] r max : maximum value of variable red time of target vehicle approach direction signal phase;

[0041] r min : minimum value of variable red time of target vehicle approach direction signal phase;

[0042] l max,i : maximum value of target vehicle approach direction queue length at target signal cycle i;

[0043] S6.2: selecting a signal timing scheme, i.e. selecting appropriate signal priority control parameters, for reference comparison of each scheme;

[0044] S7.1: establishing a delay expectation model of the target vehicle, expressed as:

[0045]

[0046] : delay expectation of the target vehicle at the signal intersection;

[0047] S7.2: calculating the delay expectation of the target vehicle in the selected signal timing scheme according to the selected signal timing scheme;

[0048] S8.1: based on the delay expectation model of the target vehicle, establishing a delay variance model of the target vehicle according to mathematical statistics theory, expressed as:

[0049] D(t d ) = E(t d 2 ) - [E(t d )] 2

[0050] D(t d ): delay variance of the target vehicle at the signal intersection;

[0051] S8.2: According to the selected signal timing scheme, calculate the delay variance of the target vehicle in the signal timing scheme;

[0052] S9.1: Based on the delay expectation and delay variance of the target vehicle, calculate the model established objective function, which contains the delay expectation of the target vehicle, the delay variance of the target vehicle and the signal adjustment time length, the expression is:

[0053]

[0054] α: the partial weight of the delay expectation of the target vehicle in the objective function;

[0055] β: the partial weight of the delay variance of the target vehicle in the objective function;

[0056] γ: the partial weight of the signal adjustment time length in the objective function;

[0057] g: the green time of the target vehicle running direction signal phase in the original signal timing scheme;

[0058] r: the red time of the target vehicle running direction signal phase in the original signal timing scheme;

[0059] S9.2: According to the selected signal timing scheme, calculate the corresponding objective function value;

[0060] S10: Determine whether the signal timing scheme is the optimal selection;

[0061] S10.1: Compare the current objective function value calculated and obtained with the minimum objective function value:

[0062] If there is no record objective function value, record the current objective function value as the minimum objective function value, and repeat step S6.2;

[0063] If the current objective function value is larger, repeat step S6.2 until the selection of all signal timing schemes is completed;

[0064] If the current objective function value is smaller, record the current objective function value as the minimum objective function value;

[0065] S10.2: According to the minimum objective function value, determine that the signal timing scheme for calculating the minimum objective function value is the optimal selection;

[0066] S11: Implement the optimal selection of the signal timing scheme.

[0067] Further, the specific steps of S3 are as follows:

[0068] S3.1: Based on the time when the target vehicle is detected by the detector, establish the delay contour of the target vehicle, and the intersection of the target vehicle travel trajectory and the delay contour is the time when the target vehicle joins the queue;

[0069] S3.2: When the target vehicle travels at a speed v k joins the queue at point B k , at which time the number of vehicles in the queue in front of the target vehicle is k, and the length of the queue is k·l car , calculate the coordinates of point B k , i.e., obtain the time and position when the target vehicle joins the queue, and the calculation formula is as follows:

[0070]

[0071] S3.3: Calculate the travel speed v k of the target vehicle when it reaches point B k according to the data of point B k , and the expression is:

[0072]

[0073] k: the number of vehicles in the queue in front of the target vehicle at the intersection.

[0074] Further, in S4, it is assumed that the number of vehicles in the queue at the intersection is a discrete distribution, subject to Poisson distribution P(λ·Δt), and the travel speed of the target vehicle is a continuous distribution, and the travel time of the target vehicle from the detector to the intersection is subject to normal distribution t t ~N(μ,σ 2 ), in order to calculate the delay duration t d of the target vehicle and the corresponding probability density f(t d ), the detailed expression of the probability density function f(t d ) of t d is:

[0075]

[0076] t: the difference between the start time of the target cycle red light and the corresponding time of the midpoint of two adjacent possible queue lengths, i.e., the difference between the midpoint time of B k and B k-1 .

[0077] v: the travel speed of the target vehicle;

[0078] k: the number of vehicles in the queue in front of the target vehicle at the intersection;

[0079] k max : the minimum travel speed v minthe maximum number of queued vehicles in front of the target vehicle at runtime;

[0080] k min : the maximum travel speed of the target vehicle max the minimum number of queued vehicles in front of the target vehicle at runtime;

[0081] l: the queue length of the intersection in front of the target vehicle;

[0082] : the arrival rate of the intersection traffic flow;

[0083] : the travel time variance of the target vehicle from the detector to the intersection;

[0084] : the mean travel time of the target vehicle from the detector to the intersection.

[0085] Further, in S7.1, the detailed expression of the probability density f(t d ) is brought into the expression of the delay expectation model E(t d ), and the delay expectation calculation model expression is obtained as follows:

[0086]

[0087] The relationship between the travel speed of the target vehicle and the number of queued vehicles at the intersection is established, and the delay expectation calculation model of the target vehicle is converted into a continuous calculation model, and the detailed expression is as follows:

[0088]

[0089] t r : the time for the queued vehicles at the intersection to completely dissipate;

[0090] v max : the maximum value of the travel speed of the target vehicle;

[0091] v min : the minimum value of the travel speed of the target vehicle.

[0092] Further, in S8.1, the detailed expression of the delay expectation model E(t d ) is brought into the expression of the delay variance model D(t d ), and the delay variance calculation model expression is obtained as follows:

[0093]

[0094] Compared with the prior art, the beneficial effects of the present application mainly lie in: considering the randomness of the intersection queue and the randomness of the target vehicle speed, and providing accurate signal priority control for the target vehicle under the condition of no bus lane.

[0095] The signal priority control method based on the bus lane condition is used to improve the reliability of the demand response vehicle priority at the bus lane signal intersection. First, the target vehicle delay probability density function is established based on the auxiliary line of the target vehicle delay contour, which is used to describe the interaction mechanism between the target vehicle and other vehicles at the signal intersection. Based on the target vehicle delay probability density function, the accurate target vehicle delay expectation and variance calculation mathematical model is established. On this basis, the target function of the signal priority control method is proposed, and the boundary conditions are discussed. BRIEF DESCRIPTION OF DRAWINGS

[0096] Figure 1 The flow chart of the signal priority control method based on the bus lane condition in the application;

[0097] Figure 2 The schematic diagram of the target vehicle trajectory on the target vehicle delay contour in the application;

[0098] Figure 3 The schematic diagram of the target vehicle discrete arrival on the target vehicle delay contour in the application. DETAILED DESCRIPTION

[0099] The signal priority control method based on the bus lane condition in the application will be described in more detail below in conjunction with the schematic diagram, wherein the preferred embodiment of the application is represented, and it should be understood that the person skilled in the art can modify the application described herein while still achieving the advantageous effects of the application. Therefore, the following description should be understood as a broad knowledge for the person skilled in the art, and not as a limitation on the application.

[0100] In the description of the application, it should be noted that for the orientation words, such as the terms "center", "transverse", "longitudinal", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. indicate the orientation and positional relationship based on the orientation or positional relationship shown in the drawings, which is only for the purpose of facilitating the description of the application and simplifying the description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and cannot be understood as limiting the specific protection scope of the application.

[0101] The application will be described in more detail in the following paragraphs with reference to the drawings. The advantages and features of the application will be more apparent from the following description. It should be noted that the drawings are very simplified and all use non-precise proportions, only for the purpose of facilitating, clarifying and assisting the description of the embodiments of the application.

[0102] As Figure 1As shown, this invention proposes a signal priority control method based on the condition of no dedicated bus lane, including the following steps:

[0103] S1: Data acquisition, investigating traffic information at intersections, including traffic flow arrival patterns, distribution patterns of target vehicle travel speeds, dissipation speed of queued traffic, signal timing schemes, and pedestrian crossing distances, in order to obtain input parameters for the model;

[0104] S2: Install vehicle detectors upstream of the intersection. The distance between the detectors and the intersection is greater than the maximum queue length. Obtain the arrival time of the target vehicle through the detectors.

[0105] S3: Based on the arrival time of the target vehicle detected by the detector, predict the delay of the target vehicle to the intersection and establish the delay contour line of the target vehicle to calculate the time and position of the target vehicle joining the queue.

[0106] S3.1: Based on the time when the target vehicle is detected by the detector, such as Figure 1 As shown, establish the delay contour lines for the target vehicle. Figure 1 The thick dashed line in the diagram, and the x-coordinate of the intersection point of the delay contour line and the target vehicle's travel trajectory, represent the time when the target vehicle joins the queue.

[0107] S3.2: As Figure 2 As shown, when the target vehicle travels at a speed v k In B k At point k, a vehicle joins the queue. The queue length is k·l. car Calculate B k The coordinates of the point, i.e., the time and position of the target vehicle joining the queue, are obtained using the following formula:

[0108]

[0109] S3.3: According to B k Calculate the data at point B to determine the target vehicle's arrival time at point B. k The travel speed v corresponding to the point k The expression is:

[0110]

[0111] k: The number of vehicles queuing at the intersection ahead of the target vehicle.

[0112] S4: Establish a queued vehicle dissipation wave parallel to the delay contour line. By calculating the time difference between the queued vehicle dissipation wave and the target vehicle delay contour line at the same location, the delay time t of the target vehicle at the intersection can be obtained. d Due to the delay time t dThe target vehicle's travel speed and the number of queued vehicles at the intersection, i.e., the target vehicle's delay duration t at the intersection d The expression of the corresponding probability density function f(t d )

[0113] f(t d ) = P(k(t d )) · g(v(t d ))

[0114] f(t d ): the corresponding probability density when the target vehicle has a delay duration t d at the intersection;

[0115] P(k(t d )): the probability that the number of queued vehicles at the intersection is k when the target vehicle has a delay duration t d at the intersection;

[0116] k(t d ): the corresponding number of queued vehicles at the intersection when the target vehicle's travel trajectory intersects the delay contour;

[0117] g(v(t d )): the probability density of the target vehicle's travel speed v when the target vehicle has a delay duration t d at the intersection;

[0118] v(t d ): the corresponding target vehicle's travel speed when the target vehicle's travel trajectory intersects the delay contour;

[0119] and the relationship between k(t d ) and v(t d ) is:

[0120]

[0121] t re : the end time of the red light of the target signal cycle;

[0122] t d : the delay duration of the target vehicle at the intersection;

[0123] l car : the average length of a unit of queued vehicles;

[0124] w: the speed of the queue dissipation wave;

[0125] t0: the current time when the target vehicle reaches the detector;

[0126] l0: the distance between the intersection and the detector;

[0127] In S4, assuming that the number of queuing vehicles at the intersection is a discrete distribution, subject to Poisson distribution P(λ·Δt), and assuming that the target vehicle travel speed is a continuous distribution, the travel time of the target vehicle from the detector to the intersection is subject to normal distribution t t ~N(μ,σ 2 , for detailed calculation of the target vehicle delay time t d and the corresponding probability density f(t d ), the probability density function of t d is f(t d ):

[0128]

[0129] t: the difference between the target cycle red light start time and the time corresponding to the midpoint of the two adjacent possible queuing lengths, i.e. B k and B k-1 midpoint time difference;

[0130] v: target vehicle travel speed;

[0131] k: the number of queuing vehicles at the intersection in front of the target vehicle;

[0132] k max : the maximum number of queuing vehicles in front of the target vehicle when running at the minimum travel speed v min ;

[0133] k min : the minimum number of queuing vehicles in front of the target vehicle when running at the maximum travel speed v max ;

[0134] l: the queuing length in front of the target vehicle at the intersection;

[0135] λ: the arrival rate of the intersection traffic flow;

[0136] σ: the variance of the travel time of the target vehicle from the detector to the intersection;

[0137] μ: the mean of the travel time of the target vehicle from the detector to the intersection.

[0138] S5: Determine the maximum queuing length of the queuing vehicles in front of the target vehicle;

[0139] S5.1: If the signal state at the current time t0 is green, calculate the time interval between the last red light start time and the current time as t;

[0140] S5.2: Calculate the cumulative probability of queuing vehicles k in time t, until the cumulative probability approaches 100%, expressed as:

[0141]

[0142] S5.3: compare the current time with the maximum queue length k*l car with the position where the queue dissipates, that is, when , determine whether the queue has completely dissipated at this time:

[0143] If k*l car is large, the queue has not completely dissipated, the current time t0 is increased by 1, that is, t0=t0+1, and step S5.1 is repeated;

[0144] If k*l car is small, the current time queue has completely dissipated, and the maximum queue length in a cycle is lcar max ;

[0145] Since the maximum queue length of the intersection is determined according to the intersection of the queue wave and the dissipation wave, but this determination method is only applicable to the arrival rate of the queue traffic flow subject to uniform distribution, and in actual situation, the arrival rate of the intersection traffic flow does not meet the characteristics of uniform arrival. Therefore, the present application considers that the arrival of intersection traffic flow is random, and according to the characteristics of random arrival of vehicle flow, the determination method in the present application is designed to determine the maximum queue length of the intersection.

[0146] S6.1: generate a plurality of different signal timing schemes according to the display time length of the green light and the red light in the adjustment, that is, realize priority control by changing the signal timing scheme of the target cycle;

[0147] By adopting the strategy of green light extension and red light early breaking, the target vehicle is given priority control, the signal adjustment time in the signal timing scheme should meet the minimum green light time requirement of the pedestrian crossing, and the target vehicle can avoid secondary queuing, that is, the value range of each signal priority control parameter in the signal timing scheme is as follows:

[0148] g min ≤g i ≤g max

[0149] r min ≤r i ≤r max

[0150]

[0151] g i : variable green light time of target signal cycle i;

[0152] g max : maximum value of variable green light time of target vehicle travel direction signal phase;

[0153] gmin The minimum value of the variable green light time for the phase of the target vehicle's travel direction signal;

[0154] r i : The variable red light time of the target signal period i;

[0155] r max The maximum value of the variable red light time for the phase of the target vehicle's travel direction signal;

[0156] r min The minimum value of the variable red light time for the phase of the target vehicle's travel direction signal;

[0157] l max,i The maximum value of the queue length at the intersection ahead of the target vehicle in the target signal period i;

[0158] S6.2: Select a signal timing scheme, that is, select appropriate signal priority control parameters for reference and comparison among various schemes;

[0159] S7.1: Establish the expected delay model for the target vehicle, expressed as:

[0160]

[0161] Expected delay of the target vehicle at the signalized intersection;

[0162] In S7.1, the probability density f(t) is... d Substitute the detailed expression of ) into the delay expectation model E(t) d From the expression, the expression for the delay expectation calculation model is obtained as follows:

[0163]

[0164] Since the discrete summation of the number of queued vehicles in the delay expectation model is inconvenient to calculate using a computer, in order to further improve the feasibility of the delay expectation calculation model for the target vehicle, this application, based on... Figure 2 Based on the geometric relationship shown, a formula is established to relate the target vehicle's travel speed to the number of vehicles queuing at the intersection. This transforms the expected delay calculation model for the target vehicle into a continuous calculation model. The detailed expression is as follows:

[0165]

[0166] t r The time it takes for the queue of vehicles at the intersection to completely dissipate;

[0167] v max The maximum speed of the target vehicle during its journey;

[0168] v min: minimum value of target vehicle travel speed.

[0169] S7.2: According to the selected signal timing scheme, the delay expectation of the target vehicle in the signal timing scheme is calculated;

[0170] S8.1: Based on the delay expectation model of the target vehicle, a delay variance model of the target vehicle is established according to the mathematical statistics theory, and the expression is:

[0171] D(t d )=E(t d 2 )-[E(t d )] 2

[0172] D(t d ):delay variance of the target vehicle at the signal intersection;

[0173] The detailed expression of the delay expectation model E(t d ) is brought into the expression of the delay variance model D(t d ), and the expression of the delay variance calculation model is obtained as:

[0174]

[0175] S8.2: According to the selected signal timing scheme, the delay variance of the target vehicle in the signal timing scheme is calculated;

[0176] S9.1: Based on the delay expectation and the delay variance of the target vehicle, a target function of the model is calculated, the target function includes the delay expectation of the target vehicle, the delay variance of the target vehicle and the signal adjustment time length, the delay expectation and the delay variance of the target vehicle guarantee the reliability and efficiency of the target vehicle travel, and the signal adjustment time length guarantees the negative influence of the signal timing scheme of the target vehicle signal priority control on other vehicles at the signal intersection, and the expression is:

[0177]

[0178] α: partial weight of the delay expectation of the target vehicle in the target function;

[0179] β: partial weight of the delay variance of the target vehicle in the target function;

[0180] γ: partial weight of the signal adjustment time length in the target function;

[0181] g: green time of the signal phase in the running direction of the target vehicle in the original signal timing scheme;

[0182] r: red time of the signal phase in the running direction of the target vehicle in the original signal timing scheme;

[0183] S9.2: According to the selected signal timing scheme, the corresponding target function value is calculated;

[0184] S10: Determine whether the signal timing scheme is the optimal selection;

[0185] S10.1: Compare the current target function value obtained by calculation with the minimum target function value:

[0186] If there is no record target function value, record the current target function value as the minimum target function value, and repeat step S6.2;

[0187] If the current target function value is larger, repeat step S6.2 until the selection of all signal timing schemes is completed;

[0188] If the current target function value is smaller, record the current target function value as the minimum target function value;

[0189] S10.2: According to the minimum target function value, determine that the signal timing scheme for calculating the minimum target function value is the optimal selection;

[0190] S11: Implement the optimal signal timing scheme.

[0191] In summary, in the embodiment, the signal priority control method based on the condition of no bus lane is proposed, and the core idea of the application is to improve the reliability of the demand response vehicle priority at the signal intersection under the condition of no bus lane by considering the signal priority control method of the vehicle travel random process under the condition of no bus lane. First, based on the auxiliary line of the "target vehicle delay contour", the target vehicle delay probability density function is established to describe the interaction mechanism of the target vehicle and other vehicles at the signal intersection. Based on the target vehicle delay probability density function, an accurate target vehicle delay expectation and variance calculation mathematical model is established. On this basis, a target function of the signal priority control method is proposed, and the boundary conditions are discussed.

[0192] The above is only the preferred embodiment of the present application, and does not limit the present application in any way. Any person skilled in the art can make any form of equivalent replacement, modification or change to the technical solutions and technical contents disclosed in the present application without departing from the scope of the technical solutions of the present application, which still belongs to the protection scope of the present application.

Claims

1. A signal priority control method based on the condition of no dedicated bus lane, characterized in that, Includes the following steps: S1: Data acquisition, investigating traffic information at intersections, including traffic flow arrival patterns, distribution patterns of target vehicle travel speeds, dissipation speed of queuing traffic, signal timing schemes, and pedestrian crossing distances, in order to obtain input parameters for the model; S2: A vehicle detector is installed upstream of the intersection, and the distance between the detector and the intersection is greater than the maximum queue length. The arrival time of the target vehicle is obtained through the detector. S3: Based on the arrival time of the target vehicle detected by the detector, predict the delay of the target vehicle to the intersection, and establish the delay contour line of the target vehicle to calculate the time and position of the target vehicle joining the queue. S3.1: Based on the time when the target vehicle is detected by the detector, establish the delay contour line of the target vehicle. The x-coordinate of the intersection point of the delay contour line and the target vehicle's travel trajectory is the time when the target vehicle joins the queue. S3.2: When the target vehicle travels at a travel speed v k In B k Join the queue at point k, where the number of vehicles ahead is k and the queue length is k·l. car Calculate B k The coordinates of the point, i.e., the time and position of the target vehicle joining the queue, are obtained. The calculation formula is as follows: S3.3: According to B k The data from the points is used to calculate the target vehicle's arrival at point B. k The travel speed v corresponding to the point k The expression is: k: Number of vehicles queuing at the intersection ahead of the target vehicle; S4: Establish a queued vehicle dissipation wave parallel to the delay contour line. By calculating the time difference between the queued vehicle dissipation wave and the target vehicle delay contour line at the same location, obtain the delay time t of the target vehicle at the intersection. d That is, the delay time t of the target vehicle at the intersection. d The corresponding probability density f(t) d The expression for the function is: f(t d )=P(k(t d ))·g(v(t d )); f(t d The target vehicle experiences a delay of duration t at the intersection. d When, the corresponding probability density; P(k(t d The target vehicle experiences a delay of duration t at the intersection. d The probability that the number of vehicles queuing at the intersection ahead is k. k(t d ): The number of vehicles queuing at the intersection where the trajectory of the target vehicle intersects with the delay contour line; g(v(t d The target vehicle experiences a delay of duration t at the intersection. d The probability density of the target vehicle's travel speed being v; v(t d ): The speed of the target vehicle when its trajectory intersects with the delay contour line; And k(t) d ) and v(t) d The relation is: t re The red light end time of the target signal cycle; t d The delay time of the target vehicle at the intersection; l car The average length of vehicles queuing per unit; w: Wave velocity of the dissipating queue wave; t0: The current time when the target vehicle arrives at the detector; l0: The distance between the intersection and the detector; In S4, it is assumed that the number of vehicles queuing at the intersection is discretely distributed and follows a Poisson distribution P(λ·Δt), and that the travel speed of the target vehicle is continuously distributed. It is also assumed that the travel time of the target vehicle from the detector to the intersection follows a normal distribution t. t ~N(μ,σ 2 To calculate the delay time t of the target vehicle in detail. d and the corresponding probability density f(t) d ), t d The probability density f(t) d The detailed expression for the function is: t: The difference between the start time of the red light in the target cycle and the time corresponding to the midpoint of two adjacent queue lengths, i.e., B k With B k-1 The difference at the midpoint; v: Target vehicle travel speed; k: Number of vehicles queuing at the intersection ahead of the target vehicle; k max The target vehicle travels at its minimum travel speed v min Maximum number of vehicles in the queue at runtime; k min The target vehicle travels at its maximum speed v. max Minimum number of vehicles in the queue at runtime; l: The length of the queue at the intersection in front of the target vehicle; λ: Arrival rate of traffic flow at the intersection; σ: Variance of the travel time of the target vehicle from the detector to the intersection; μ: The average travel time of the target vehicle from the detector to the intersection; S5: Determine the maximum queue length of vehicles queuing in front of the target vehicle; S5.1: If the signal status at the current time t0 is green, then calculate the time interval between the start time of the previous red light and the current time as t; S5.2: Calculate the cumulative probability of queued vehicle k within time t, the expression is: S5.3: Set the maximum queue length k·l at the current time. car Compare with the location where the queue has dissipated, i.e., when At this point, determine whether the queue has completely dissipated: If k·l car If the value is large, the queue has not completely dissipated. Increment the current time t0 by 1, i.e., t0 = t0 + 1, and repeat step S5.

1. If k·l car If the value is small, the queue has completely dissipated at the current time, and the maximum queue length within one cycle is... S6.1: Based on the display duration of the green and red lights during the adjustment, generate a variety of different signal timing schemes, that is, achieve priority control by changing the signal timing scheme of the target cycle; The value ranges of each signal priority control parameter in the signal timing scheme are as follows: g min ≤g i ≤g max ; r min ≤r i ≤r max ； g i : The variable green light time of the target signal period i; g max The maximum value of the variable green light time for the phase of the target vehicle's travel direction signal; g min The minimum value of the variable green light time for the phase of the target vehicle's travel direction signal; r i : The variable red light time of the target signal period i; r max The maximum value of the variable red light time for the phase of the target vehicle's travel direction signal; r min The minimum value of the variable red light time for the phase of the target vehicle's travel direction signal; l max,i The maximum value of the queue length at the intersection ahead of the target vehicle in the target signal period i; S6.2: Select one of the signal timing schemes, that is, select appropriate signal priority control parameters for reference comparison among the schemes; S7.1: Establish the expected delay model for the target vehicle, expressed as: Expected delay of the target vehicle at the signalized intersection; r: The red light time of the target vehicle's direction of travel signal phase in the original signal timing scheme; The probability density f(t) d Substitute the detailed expression of ) into the delay expectation model E(t) d From the expression, the expression for the delay expectation calculation model is obtained as follows: A relationship is established between the travel speed of the target vehicle and the number of vehicles queuing at the intersection. The expected delay calculation model for the target vehicle is then converted into a continuous calculation model. The detailed expression is as follows: t r The time it takes for the queue of vehicles at the intersection to completely dissipate; v max The maximum speed of the target vehicle during its journey; v min The minimum travel speed of the target vehicle; S7.2: Based on the selected signal timing scheme, calculate the expected delay of the target vehicle in the signal timing scheme; S8.1: Based on the expected delay model of the target vehicle, and according to mathematical statistics theory, a delay variance model for the target vehicle is established, expressed as follows: D(t d )=E(t d 2 )-[E(t d )] 2 ; D(t d ): The variance of the delay of the target vehicle at the signalized intersection; S8.2: Calculate the delay variance of the target vehicle in the selected signal timing scheme; S9.1: Based on the expected delay and variance of the target vehicle, calculate the objective function of the model. The objective function includes the expected delay of the target vehicle, the variance of the target vehicle's delay, and the signal adjustment time. The expression is: α: The partial weight of the expected delay of the target vehicle in the objective function; β: The partial weight of the delay variance of the target vehicle in the objective function; γ: The weight of the signal adjustment time in the objective function; g: Green light time for the target vehicle's direction of travel signal phase in the original signal timing scheme; r: The red light time of the target vehicle's direction of travel signal phase in the original signal timing scheme; S9.2: Calculate the corresponding objective function value based on the selected signal timing scheme; S10: Determine whether the signal timing scheme is the optimal choice; S10.1: Compare the calculated current objective function value with the minimum objective function value: If no objective function value is recorded, record the current objective function value as the minimum objective function value and repeat step S6.2; If the current objective function value is large, repeat step S6.2 until all the signal timing schemes have been selected; If the current objective function value is small, record the current objective function value as the minimum objective function value; S10.2: Based on the minimum objective function value, determine the optimal signal timing scheme for calculating and obtaining the minimum objective function value; S11: Implement the optimal signal timing scheme.

2. The signal priority control method based on the condition of no dedicated bus lane as described in claim 1, characterized in that, In S8.1, the delay expectation model E(t) is used. d Substitute the detailed expression of ) into the delay variance model D(t) d From the expression, the expression for the delay variance calculation model is obtained as follows:

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