Vehicle-road cooperation signal priority control method and system

Abstract

According to the vehicle-road cooperation signal priority control method and system provided by the invention, a preset range is set, that is, when a bus is in an area close to an intersection, the response to a bus priority control strategy is started, and the interference of control delay in travel time is overcome. In the aspect of control calculation, time difference calculation is carried out according to the time when a bus arrives at an intersection and the center distance of a bus phase, certain buffer time is given to the bus, and the influence of speed fluctuation on the control effect is avoided; and secondly, in the calculation process of a specific phase control strategy, speed fluctuation in the driving process is fully considered, optimization is carried out based on the interval interval minimum target of the driving interval and the bus phase, and the risk of control failure can be effectively reduced through double guarantee. Besides, the control strategy only relates to at most one half cycle, and only phase compression and phase extension do not relate to signal insertion and jump, so that traffic disorder and interference on normal driving order caused by frequent phase change are avoided.

Description

Technical Field

[0001] The present invention belongs to the technical field of intelligent transportation systems and control, and particularly relates to a vehicle-road collaborative signal priority control method and system. Background Art

[0002] With the annual increase in the number of motor vehicles, road congestion has intensified. How to alleviate congestion, improve travel efficiency, and reduce the time and economic losses caused by congestion has become a hot research issue in the transportation industry. Encouraging the development of public transportation can effectively alleviate traffic congestion, increase the proportion of intensive travel, contribute to the zero-carbon city vision to a certain extent. Ensuring the priority of public transportation in terms of time and space is an important measure to improve the attractiveness of public transportation to travel. Therefore, studying bus priority has practical significance.

[0003] At present, the bus priority control on urban roads is mainly divided into spatial priority and time priority. Spatial priority mainly gives priority to buses in terms of road rights; time priority mainly gives buses time priority by changing signal phases. Due to the randomness of traffic flow and the instability of bus driving speeds, it is easy to cause the failure of bus priority control. With the development of vehicle-road collaborative technology, the contradictions in existing traffic control can be effectively solved. Abundant sensing devices and real-time data enable buses and roads to transmit real-time information to the bus priority control system, receive the command information sent by the system, and at the same time can give a certain feedback to the bus priority system, making the bus priority control more stable and reliable.

[0004] Although bus priority based on vehicle-road collaborative technology has achieved good results in practice, there are still the following problems in practice: 1. The utilization of new types of real-time data in current traffic control is insufficient. In the vehicle-road collaborative scenario, there are bus trajectory data of radar-vision integrated machines, various types of real-time traffic parameters, bus positioning location data, and digital traffic signs and markings. These rich data in the vehicle-road collaborative scenario have not been fully utilized in traffic control. 2. The influence of the fluctuation of bus driving speed and the boarding and alighting time at bus stops on the control strategy. When the bus driving speed fluctuates or the boarding and alighting time of the bus fluctuates, the bus priority control strategy is prone to failure. Therefore, in the process of bus priority control, the influence of factors such as travel time fluctuation and control delay on the control strategy should be fully considered; 3. The accumulation of errors. Many control strategies intervene too early, and the errors caused by intersection signal control, driving speed fluctuation, and stop time fluctuation during the bus driving process will accumulate, resulting in control failure. 4. The interference with normal traffic flow. Frequent changes in phase duration and phase jumps will interfere with the normal driving of other buses. Although the bus phase is guaranteed, the bus delays of other phases increase, the driving risk increases, and traffic accidents are easily induced. Summary of the Invention

[0005] The present invention provides a vehicle-road collaborative signal priority control method and system, which reduces the interference of travel time fluctuations and control delays on signal priority control.

[0006] The present invention provides a vehicle-road collaborative signal priority control method, and the method includes:

[0007] When the time of the bus from the intersection is within the range of the bus priority response position, a priority control request is initiated;

[0008] Calculate the time for the bus to reach the intersection, and obtain the previous signal phase when the bus reaches the intersection;

[0009] Calculate the duration required for the bus to reach the midpoint of the last bus phase in the forward direction when the previous signal phase is extended, and determine whether to extend the previous signal phase according to the duration; calculate the duration required for the bus to reach the midpoint of the first bus phase in the backward direction when the previous signal phase is compressed, and determine whether to compress the previous signal phase according to the duration;

[0010] If it is determined that the previous signal phase needs to be compressed or extended, calculate the maximum compression phase and the maximum extension phase of the signal lamp, and determine which bus priority control strategy to adopt according to the durations of the maximum compression phase and the maximum extension phase;

[0011] If it is determined that the previous signal does not need to be compressed or extended, when the vehicle reaches the intersection, the signal lamp is in the bus phase.

[0012] Further, when the time of the vehicle from the intersection is less than 1.5 signal lamp phase cycle durations, the priority control request is initiated.

[0013] Further, calculating the time for the bus to reach the intersection includes: respectively calculating the average time, the earliest time, and the latest time for the bus to reach the intersection;

[0014] The calculation method of the average time is:

[0015] The calculation method of the earliest time is:

[0016] The calculation method of the latest time is:

[0017] Wherein, L is the distance between the bus and the intersection, v av , v max and v min are the average speed, the maximum speed, and the minimum speed respectively; t av , t min , t maxThey are the expected times required for the bus to reach the intersection when traveling at the average speed, maximum speed, and minimum speed respectively; η is the influence of the platform within the intersection, taking 1 when there is a platform and 0 when there is none; t sav , t smin , t smax are the average values of the bus stop times at the platform respectively.

[0018] Furthermore, when calculating the extension of the previous signal phase, the duration required for the bus to reach the intersection and catch up with the midpoint of the previous bus phase is:

[0019]

[0020] When calculating the compression of the previous signal phase, the duration required for the bus to reach the intersection and catch up with the midpoint of the next bus phase is:

[0021]

[0022] where, Δt 1 is the duration required for the bus to reach the intersection and catch up with the midpoint of the last bus phase in the forward direction when the previous phase is extended, Δt 2 is the duration required for the bus to reach the intersection and catch up with the midpoint of the first bus phase in the backward direction when the previous phase is shortened, c is the total duration of one phase of the signal light; c g is the green light duration of each bus phase; t 1 is the time difference between the current phase and the start of the next bus phase, mod is the modulo operation;

[0023] When or , there is no need to compress or extend the previous signal phase.

[0024] Furthermore, it also includes: calculating the minimum green light duration in any phase of the signal light;

[0025] The minimum green light duration in the i-th phase of the signal light is:

[0026] where, G i人 is the minimum time for pedestrians to cross the road safely in the i-th phase; k is the maximum value of the total number of queuing and passing vehicles in all directions at the intersection in the i-th phase in the previous cycle, h j is the headway of the j-th vehicle, t is the bus start-up loss time.

[0027] Furthermore, according to the minimum green light duration of the signal light phase, calculate the maximum compression time and maximum extension time of the signal light phase;

[0028] The maximum compression time is:

[0029] The minimum compression time is:

[0030] where C i is the phase duration of the i-th cycle of the signal light, C imax is the maximum duration of the i-th cycle of the signal light, G imin is the minimum green light duration of the i-th phase, p is the total number of cycles from the current time to the arrival of the bus at the intersection, and G i is the green light duration of the i-th phase.

[0031] Furthermore, when Δt 1 > Δt + or Δt 2 > Δt - a priority control strategy of compressing the previous signal phase is adopted;

[0032] When Δt 1 < Δt + or Δt 2 > Δt - a priority control strategy of extending the previous signal phase is adopted;

[0033] When Δt 1 < Δt + and Δt 2 < Δt - , and a control method combining compressing the previous signal phase and reducing the driving speed of the bus is adopted;

[0034] When Δt 1 < Δt + and Δt 2 < Δt - , and a control method combining extending the previous signal phase and increasing the driving speed of the bus is adopted.

[0035] Furthermore, when adopting the priority control strategy of compressing the previous signal phase,

[0036] if t max - t min ∈ (C gmin , C gmax ), the previous signal phase that needs to be compressed or extended is:

[0037] Δt = max(t min - t 1 - c, t max - t 1 - c - c g );

[0038] Among them, t min is the start time of the bus phase, and t max is the end time of the bus phase; c gmin is the minimum green light duration of each bus phase, and c gmax is the maximum green light duration of each bus phase, and t 1 is;

[0039] When the previous signal phase is compressed, the adjustment time of the phase duration is

[0040] When the previous signal phase is extended, the adjustment time of the phase duration is

[0041] Among them, round is rounding to the nearest integer.

[0042] Furthermore, the present invention also provides a vehicle-road collaborative signal priority control system, implementing any one of the vehicle-road collaborative signal priority control methods, including:

[0043] A data collection and perception system for collecting traffic parameters;

[0044] A vehicle information collection unit for transmitting vehicle position information to the vehicle priority control unit;

[0045] A vehicle priority control unit for determining whether the distance between the vehicle and the intersection is within a preset range. When the distance between the vehicle and the intersection is within the preset range, the vehicle position information is sent to the calculation unit;

[0046] A calculation unit for determining which bus priority control strategy to adopt according to the traffic parameters and the vehicle position information;

[0047] A feedback unit for receiving and executing the bus priority control strategy and feeding back the strategy execution situation to the calculation unit.

[0048] Compared with the prior art, the present invention provides at least the following technical effects:

[0049] The present invention overcomes the interference of control delay in travel time by setting a preset range, that is, when the bus is in an area relatively close to the intersection (a driving distance of 1.5 signal light phase periods from the intersection), the response to the bus priority control strategy starts. In terms of control calculation, the time difference is based on the central distance from the bus phase rather than the start or end time of the phase, giving the bus a certain buffer time to avoid the influence of speed fluctuations on the control effect; secondly, in the calculation process of the specific phase control strategy, the speed fluctuations during the driving process are fully considered, and the optimization is carried out based on the minimum target of the interval between the driving section and the bus phase interval, ensuring double protection and effectively reducing the risk of control failure. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 It is a simplified flowchart of the vehicle-road collaborative signal priority control method and system in Embodiment 1 of the present invention;

[0051] Figure 2 It is another simplified flowchart of the vehicle-road collaborative signal priority control method and system in Embodiment 1 of the present invention;

[0052] Figure 3 It is a simulation diagram when another bus passes through the intersection in Embodiment 1 of the present invention;

[0053] Figure 4 It is a simulation diagram when another bus passes through the intersection in Embodiment 1 of the present invention;

[0054] Figure 5 It is a simulation diagram when another bus passes through the intersection in Embodiment 1 of the present invention;

[0055] Figure 6 It is a simulation diagram when another bus passes through the intersection in Embodiment 1 of the present invention;

[0056] Figure 7 It is a simulation diagram when another bus passes through the intersection in Embodiment 1 of the present invention;

[0057] Figure 8 It is a simulation diagram when another bus passes through the intersection in Embodiment 1 of the present invention;

[0058] Figure 9 It is an intersection simulation diagram in Embodiment 3 of the present invention;

[0059] Figure 10 It is a schematic diagram of the connection relationship of the vehicle-road collaborative signal priority control in Embodiment 3 of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0060] The following will describe a vehicle-road collaborative signal priority control method and system of the present invention in conjunction with schematic diagrams, in which the preferred embodiments of the present invention are shown. It should be understood that those skilled in the art can modify the present invention described herein while still achieving the advantageous effects of the present invention. Therefore, the following description should be understood as broad knowledge for those skilled in the art and not as a limitation on the present invention.

[0061] In the following paragraphs, the present invention will be described more specifically by way of example with reference to the accompanying drawings. According to the following description, the advantages and features of the present invention will be clearer. It should be noted that the drawings are all in a very simplified form and use non-precise scales, only for the purpose of facilitating and clearly assisting in explaining the purpose of the embodiments of the present invention.

[0062] Embodiment 1

[0063] Please refer to Figures 1-6 , this embodiment provides a vehicle-road collaborative signal priority control method, and the method includes the following steps:

[0064] S1. When the distance between the bus and the intersection is within a preset range, initiate a priority control request;

[0065] S2. Calculate the time for the bus to reach the intersection, and obtain the previous signal phase when the bus reaches the intersection, as well as the last bus phase in the forward direction and the first bus phase in the backward direction when the bus reaches the intersection;

[0066] S3. Calculate the duration required for the bus to reach the midpoint of the last bus phase in the forward direction when the previous signal phase is extended, and determine whether to extend the previous signal phase according to the duration; calculate the duration required for the bus to reach the midpoint of the first bus phase in the backward direction when the previous signal phase is compressed, and determine whether to compress the previous signal phase according to the duration;

[0067] S4. If it is determined that the previous signal phase needs to be compressed or extended, calculate the maximum compression phase and the maximum extension phase of the signal lamp, and determine which priority control strategy to adopt according to the duration of the maximum compression phase and the maximum extension phase;

[0068] If it is determined that there is no need to compress or extend the previous signal phase, when the vehicle reaches the intersection, the signal lamp is in the bus phase.

[0069] Specifically, in step S1, according to the average speed v of the bus av calculate the time for the vehicle to reach the intersection. When the time for the vehicle to reach the intersection is equal to 1.5 times the duration of a signal lamp phase cycle, initiate a priority control request.

[0070] In a specific embodiment, the vehicle location information is uploaded to the platform through the OBU (On-Board Unit), which is a device installed on a bus vehicle and used to perceive vehicle location data in real time.

[0071] For further details, please refer to Figure 3 , in step S2, after the system sends a priority request, calculate the earliest time for the bus to reach the intersection at the maximum speed, the average time to reach the intersection at the average speed, and the latest time to reach the intersection at the minimum speed respectively. The specific calculation steps are as follows:

[0072]

[0073] where L is the distance between the bus and the intersection, v av , v max and v min are the average speed, the maximum speed, and the minimum speed respectively; t av , t min , t max are the required times for the bus to reach the intersection at the average speed, the maximum speed, and the minimum speed respectively; η is the influence of the platform in the intersection, taking 1 when there is a platform and 0 when there is no platform; t sav , t smin , t smax are the average values of the bus stop times at the platform respectively.

[0074] In a specific embodiment, count the stop times of all buses at the platform, calculate the average value t sav of all buses' stop times as a reference for general situations; and calculate the 5% quantile value of the bus stop times, that is, take the average value of the shortest 5% of the data, reflecting the shorter stop time t smin , calculate the 95% quantile value of the bus stop times, take the average value t smax of the longest 5% of the data, reflecting the longer stop time. Through these three statistical methods, the influence of individual extreme situations (such as abnormally long stops) on the control strategy can be avoided, making the control strategy more stable and reliable.

[0075] For further details, in step S3, the time difference between the bus phase and the bus arrival time is divided into two categories:

[0076] The first category is: when the previous phase is extended, the duration required for the bus to reach the intersection and catch up with the midpoint of the last forward bus phase. That is, when the bus arrival time is earlier than the end time of the current bus phase, the previous phase needs to be extended so that the bus can pass through the intersection during this bus phase.

[0077] The second type is: when the previous phase is compressed, the time required for the bus to reach the midpoint of the first subsequent bus phase when it arrives at the stop. That is, when the bus arrival time is later than the end time of the next bus phase, the previous phase needs to be compressed so that the bus can pass through the intersection during the next bus phase.

[0078] In this embodiment, the previous phase refers to the signal phase before the bus green light phase, which also includes the bus phase.

[0079] In this embodiment, taking the midpoint of the bus phase rather than the start or end point of the phase as the basis for calculating the time difference can overcome the influence of bus speed fluctuations and boarding / alighting stop time fluctuations on the control effect.

[0080] In a specific embodiment, the calculation formulas for the first type of time difference and the second type of time difference are respectively:

[0081]

[0082] where, Δt 1 is the time required for the bus to reach the midpoint of the last forward bus phase when it arrives at the intersection when the previous phase is extended, Δt 2 is the time required for the bus to reach the midpoint of the first backward bus phase when it arrives at the intersection when the previous phase is shortened, C is the total duration of a bus phase cycle; c g is the green light duration of each bus phase; t 1 is the time difference between the current phase and the start point of the next bus phase, and mod is the remainder operation.

[0083] In this embodiment, when or the predicted bus arrival time is within the bus phase range. At this time, the signal machine does not need to respond and can operate according to the established phase. Otherwise, continue with the control strategy calculation.

[0084] More specifically, in step S3, in order to ensure that the pedestrian waiting time is not too long and the bus delay is limited within a certain range, the maximum duration G imax of the i-th phase is preset in advance according to the actual conditions and traffic flow of each intersection.

[0085] To ensure that pedestrians and queuing buses can both pass through the intersection within the i-th phase, the minimum green light duration G imin of the i-th phase is:

[0086]

[0087] where, G i人The minimum time for pedestrians to cross the road safely in the i-th phase; k is the maximum value of the total number of queuing and passing vehicles in all directions at the intersection in the i-th phase of the previous signal cycle when the bus arrives at the intersection, h j is the headway of the j-th vehicle, and t is the starting loss time of the bus.

[0088] In a specific embodiment, a radar-vision integrated machine is used to collect the maximum value of the total number of queuing and passing buses in all directions, and the headway of different types of buses passing through the intersection.

[0089] By setting the maximum and minimum bus durations for each phase, it aims to ensure the safe crossing of pedestrians and vehicles in the remaining bus phases while reasonably controlling the bus delay time, effectively balancing the traffic efficiency, and adjusting the green light time allocation according to the actual situation of different intersections, thereby improving the overall traffic operation efficiency. Calculate the maximum compression time Δt of the signal light phase during the period from the bus response moment to the bus arrival at the intersection - and the maximum extension time Δt + :

[0090]

[0091] Among them, C i is the duration of the i-th cycle of the signal light, G imax is the maximum duration of the i-th cycle of the signal light, G imin is the minimum green light duration of the i-th phase, p is the total number of cycles from the current time to the bus arrival at the intersection, G i is the green light duration of the i-th phase.

[0092] In this embodiment, according to the time difference Δt between the time when the bus arrives at the intersection and the arrival of the bus at the bus phase 1 , Δt 2 and the adjustable time Δt of the phase - , Δt + Based on the relationship between the two, the control strategies can be divided into four categories: compressing the phase time, extending the phase time, compressing the phase time plus speed guidance, and extending the phase time plus speed guidance.

[0093] Specifically, when Δt 1 > Δt + and Δt 2 > Δt - It means that the total available compression or extension phase duration cannot meet the bus priority, and at this time, a combined control of adjusting the phase and speed guidance is required. It means that the time difference between extending the phase time and the bus arrival at the intersection is relatively close, and a control method combining extending the phase and increasing the speed can be adopted; conversely, when It indicates that the difference between the compressed phase time and the bus arrival time is relatively close, and a control method combining compressed phase and speed reduction can be adopted.

[0094] In summary, when Δt 1 > Δt + and Δt 2 < Δt - , the control method of compressing the phase is adopted. When Δt 1 < Δt + or Δt 2 > Δt - , the control method of extending the phase is adopted. When Δt 1 < Δt + and Δt 2 < Δt - , and , the control method combining compressed phase and speed reduction is adopted. When Δt 1 < Δt + and Δt 2 < Δt - , and , the control method combining extended phase and speed increase is adopted.

[0095] This embodiment adopts a combined control method combining phase adjustment and speed guidance. According to different situations of the time difference between the arrival time of the bus at the intersection and the bus phase time, different control strategies are selected. It not only considers the volatility of the bus arrival time but also takes into account the limitations of the green light duration of different phases, realizing flexible control and dynamic optimization of bus priority, thereby improving the efficiency of bus priority control.

[0096] In step S4, there are two phase adjustment strategies in total. The first type of adjustment strategy is the combined control strategy of adjusting the phase and speed induction, and the second type of adjustment strategy is to only adjust the phase duration.

[0097] Specifically, when adopting the first type of adjustment strategy, the main idea is to use speed increase to compensate for the insufficient part of the extended phase or reduce the speed to make up for the insufficient part of the compressed phase. The core of this strategy is to calculate the induced speed value and correspond it to the speed limit value of the road section.

[0098] In this embodiment, when adopting the method of combining phase compression and speed reduction, for each phase adjustment method, the previous phase compression time is implemented according to c i = G imin . Calculate the time difference remaining until the bus green light phase after phase adjustment: Δt = Δt 2 - Δt - .

[0099] Then calculate the guiding speed

[0100]

[0101] Similarly, when adopting the combined method of phase compression and speed increase control, for each phase adjustment method, the extended time of the previous phase is in accordance with c i = G imax Implement. Calculate the time difference remaining until the bus green light phase after phase adjustment: Δt = Δt 2 -Δt - .

[0102] Guided speed

[0103]

[0104] Among them, v max is the speed limit value of the road section, and specific information is provided according to the digital signs and markings.

[0105] Specifically, when adopting the second type of adjustment strategy, the main idea is to ensure that the bus can pass during the bus phase. The volatility of the bus arrival time at the intersection should be considered, so that the earliest and latest arrival times of the bus can fall within the bus phase as much as possible.

[0106] Calculate to obtain t max -t min ∈(C gmin , C gmax ) When it is necessary to adjust the phase duration Δt = max(t min -t 1 -c, t max -t 1 -c - c g ).

[0107] Among them, t min is the start time of the bus phase, t max is the end time of the bus phase; c gmin is the shortest green light duration of each bus phase, c gmax is the longest green light duration of each bus phase, t 1 is the time difference between the current phase and the start of the next bus phase.

[0108] When the previous signal phase is compressed, the specific adjustment time of the previous signal is

[0109] Among them, round is rounding to the nearest integer, Δt i is the specific adjustment time of the i-th phase, C i is the phase duration of the i-th cycle of the signal light.

[0110] When the previous signal phase is extended, the specific adjustment time for each phase is

[0111] Furthermore, if it is calculated that then when adopting the previous signal phase compression strategy, it is necessary to minimize the sum of the absolute values of the following two time differences:

[0112] The first time difference: the time difference between the earliest arrival time of the bus at the intersection and the start time of the first backward bus phase.

[0113] The second time difference: the time difference between the latest arrival time of the bus at the intersection and the end time of the first backward bus phase.

[0114] The minimum value of the sum of the absolute values of the first time difference and the second time difference is expressed as the following function:

[0115] min F(Δt)=|Δt 3 |+|Δt 4 |=|t min -(t 1 +c+Δt)|+|t max -(c gmax +t 1 +c+Δt)|

[0116] where min F(Δt) represents the minimum value of the sum of the absolute values of the first time difference and the second time difference, Δt 3 is the time difference between the earliest arrival time of the bus at the intersection and the start time of the first backward bus phase. Δt 4 is the time difference between the latest arrival time of the bus at the intersection and the end time of the first backward bus phase, t min is the start time of the bus phase, t max is the end time of the bus phase, mst.0 < Δt < Δt - , st.0 is the constraint condition.

[0117] The specific adjustment time for each phase is

[0118] If phase extension is required, it is necessary to minimize the sum of the absolute values of the following two time differences:

[0119] The third time difference: the time difference between the earliest arrival time of the bus at the intersection and the start time of the last forward bus phase.

[0120] The fourth time difference: the time difference between the latest arrival time of the bus at the intersection and the end time of the last forward bus phase.

[0121] The minimum value of the sum of the absolute values of the third time difference and the fourth time difference is expressed as the following function:

[0122] min F(Δt)=|Δt 3 |+|Δt 4 |=|t min -(t 1 +c+Δt)|+|t max -(c gmax +t 1 +c+Δt)|

[0123] where 0 < Δt < Δt + , st.0 is a constraint condition, Δt 3 is the time difference between the earliest arrival time of the bus at the intersection and the start time of the last bus phase in the forward direction, Δt 4 is the time difference between the latest arrival time of the bus at the intersection and the end time of the last bus phase in the forward direction, t min is the start time of the bus phase, t max is the end time of the bus phase,

[0124] The specific time for each phase adjustment is

[0125] In summary, in this embodiment, when the bus is in the area relatively close to the intersection (1.5 cycle driving distances from the intersection), the bus priority control strategy starts to respond, overcoming the interference of control delay in the travel time. In terms of control calculation, the time difference is based on the central distance from the bus phase rather than the start or end time of the phase, giving the bus a certain buffer time to avoid the impact of speed fluctuations on the control effect; secondly, in the calculation process of the specific phase control strategy, the speed fluctuations during the driving process are fully considered, and the optimization is carried out based on the minimum target of the interval between the driving interval and the bus phase interval, ensuring double protection can effectively reduce the risk of control failure. There is a departure feedback mechanism after the vehicle leaves, which can feedback on the control strategy, facilitating the quantitative evaluation of the control strategy. The control strategy only involves at most one and a half cycles, and only phase compression and phase extension are involved without signal insertion or jumping, which can try to ensure the original control orientation and will not frequently change the phase to cause traffic chaos and interfere with the normal driving order.

[0126] Embodiment 2

[0127] Based on the vehicle-road collaborative signal priority control method provided in Embodiment 1, this embodiment provides a specific implementation case.

[0128] Specifically, the intersection is a four-phase controlled intersection, the signal light has a cycle duration c = 100s, where P 1The north-south straight lane is a bus phase with a phase duration of c 1 = c g = 36s; P 2 North-south left turn, with a phase duration of c 2 = 20s, P 3 East-west straight lane, with a phase duration of c 3 = 30s; P 4 For the east-west left turn, the phase duration is c 4 = 14s. The road section is 1500m long, and the average driving speed of the bus is v av = 50km / h, v max = 60km / h, v min = 40km / h.

[0129] From Figure 6 it can be seen that when the bus priority response is in P 3 phase, it is 40s away from the next bus phase.

[0130] First step, calculate the expected arrival time of the bus: t av = 108s, t min = 90s, t max = 135s.

[0131] Second step, according to the actual situation of the intersection, in this embodiment, it is assumed that: G 1min = 24s, G 2min = 12s, G 3min = 18s, G 4min = 12s; G 1max = 55s, G 2max = 35s, G 3max = 45s, G 1max = 25s.

[0132] Calculate t max - t min = 45 ∈ (24, 55), at this time, take 45 as the bus phase duration. Control the bus phase time to be from the 90th s to the 135th s.

[0133] Third step, calculate the time difference between the arrival time of the vehicle at the intersection and the time of the last forward and the first backward bus phases, which are Δt 1 = max(90 - 35, 135 - 71) = 64, Δt 2 = max(135 - 90, 165 - 135) = 45.

[0134] Calculate Δt according to each phase duration and the maximum and minimum phase durations + = 15 + 11 + 19 = 45s, Δt - = 12 + 2 + 12 + 8 + 12 + 2 = 48s.

[0135] According to Δt 1 , Δt 2 , Δt + , Δt - , it can be known from the magnitude of Δt that if Δt 1 > Δt + and Δt 2 < Δt - , then the control method of compressed phase should be adopted at this time.

[0136] Step 4, calculate the specific adjustment plan. Take Δt as 45s, and the specific adjustment plan is as follows: The bus phase is 90 - 135s, and the time compressed and allocated to each specific phase is:

[0137]

[0138] For the specific control plan, please refer to Figure 7 : In the current cycle, the third phase C 3 = 19s, the fourth phase C 4

[0139] = 12s; In the next cycle: the first phase C 1 = 25, the second phase C 2 = 12, the third phase C 3 = 19, the fourth phase C 4 = 12, and the bus arrival phase C 1 = 45.

[0140] Embodiment 3

[0141] Please refer to Figure 9 and Figure 10 , this embodiment provides a vehicle-road collaborative signal priority control system, and the system includes:

[0142] A data collection and perception system for collecting traffic parameters.

[0143] A vehicle information collection unit for transmitting vehicle position information to the vehicle priority control unit.

[0144] A vehicle priority control unit for judging whether the distance between the vehicle and the intersection is within a preset range, and when the distance between the vehicle and the intersection is within the preset range, sending the position information of the vehicle to the calculation unit.

[0145] A calculation unit for judging which bus priority control strategy to adopt according to the traffic parameters and the vehicle position information.

[0146] A feedback unit for receiving and executing the bus priority control strategy and feeding back the strategy execution situation to the calculation unit.

[0147] In a specific embodiment, the data acquisition and perception system is a Rayleigh all-in-one machine, which is used to perceive vehicle trajectory data and traffic parameters (including: parameters such as traffic flow, vehicle type, time headway, queue length, etc.). Among them, the Rayleigh all-in-one machine can be arranged about 30m from the stop line at each approach of the intersection.

[0148] In another specific embodiment, the vehicle information acquisition unit includes a roadside unit (RSU) and an on-vehicle unit (OBU). The on-vehicle unit is installed on a bus and is used to perceive vehicle position data in real time, and transmit the in-vehicle sensing data to the computing unit through the roadside unit. The roadside unit is used to receive the information transmitted by the on-vehicle unit and send information to the on-vehicle unit.

[0149] In another specific embodiment, the vehicle priority control unit is a bus priority platform.

[0150] In another specific embodiment, the computing unit is an edge computing device (MEC). After receiving vehicle position, bus priority requests, traffic parameters published by the Rayleigh vision integrated machine, and judging the signal control plan, the MEC calculates the specific control method and sends it to the signal machine. The edge computing device is also used to receive the feedback information of the bus passing through the intersection fed back by the signal collector, and the edge computing device cancels the calculation of the priority request to complete the signal priority control. Among them, the MEC is arranged in the intersection floor cabinet.

[0151] In another specific embodiment, the feedback unit includes a signal machine and a signal collector. The signal machine is used to receive and execute the bus priority control strategy, and the signal collector is used to collect and upload the intersection signal phase information in real time and feedback the strategy execution situation to the MEC. Among them, the signal collector is also arranged in the intersection floor cabinet.

[0152] Specifically, in this embodiment, when the bus is outside the communication range of the intersection RSU, the on-vehicle unit OBU transmits the position information of the bus to the bus priority platform via the Uu (4G or 5G cellular network). When the bus priority platform determines that the bus is within the bus priority response position range, it transmits the position information to the edge computing device. When the bus is within the communication range of the intersection RSU, the OBU transmits information such as the position of the bus to the RSU via PC5 (dedicated short-range communication). After receiving the OBU information, the RSU transmits it to the MEC via Ethernet. After receiving the vehicle position, bus priority request, traffic parameters of the radar-vision integrated machine, the MEC calculates the signal control plan and gives the specific control method, and then issues it to the signal machine. After the signal machine executes the bus priority control strategy, the bus leaves the intersection, and the bus phase information is uploaded to the MEC through the signal collector. The MEC evaluates the control effect based on this. After the bus passes through the intersection, it sends the departure information to the MEC via the RSU through the OBU. At this moment, the MEC cancels the calculation of the signal priority request and completes the signal priority control.

[0153] In this embodiment, the on-vehicle unit senses the real-time position of the vehicle, the radar-vision integrated machine senses the traffic history and real-time parameters, the roadside unit uploads and issues information, the signal collector collects the phase state of the signal machine, and at the same time relies on the edge computing device to calculate and generate the control strategy, issue the control strategy, and feedback on the departure of the bus. It realizes the bus priority control in the vehicle-road collaborative environment.

[0154] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention is also intended to include these changes and modifications.

Claims

1. A vehicle-road cooperative signal priority control method, characterized in that: The method comprises: When the time between the bus and the intersection is within the bus priority response position range, a priority control request is initiated; Calculate the time when the bus arrives at the intersection, and obtain the preamble signal phase when the bus arrives at the intersection; Calculate the time required for the bus to catch up with the middle point of the last bus phase in the forward direction when the preamble signal phase is extended, and determine whether the preamble signal phase needs to be extended according to the time; calculate the time required for the bus to catch up with the middle point of the first bus phase in the backward direction when the preamble signal phase is compressed, and determine whether the preamble signal phase needs to be compressed according to the time; If it is determined that the phase of the preceding signal needs to be compressed or extended, the maximum compression phase and the maximum extension phase of the signal light are calculated, and the bus priority control strategy to be adopted is determined according to the duration of the maximum compression phase and the maximum extension phase; If it is determined that there is no need to compress or extend the preceding signal, the signal light is in the public transportation phase when the vehicle arrives at the intersection.

2. The vehicle-road cooperative signal priority control method according to claim 1, characterized in that: When the distance between the vehicle and the intersection is less than 1.5 signal light phase cycle durations, the priority control request is initiated.

3. The vehicle-road cooperative signal priority control method according to claim 1, characterized in that: Calculating the time for a bus to arrive at an intersection includes: respectively calculating the average time, the earliest time and the latest time for the bus to arrive at the intersection; The average time is calculated as follows: The earliest time is calculated as follows: The latest time is calculated as follows: Where L is the distance between the bus and the intersection, v av , v max and v min are the average speed, maximum speed and minimum speed respectively; t av , t min , t max are the estimated time required for the bus to reach the intersection when traveling at the average speed, maximum speed, and minimum speed respectively; η is the impact of the platform at the intersection, which is 1 when there is a platform and 0 when there is no platform; t sav , t smin , t smax are the average stop time of buses at the bus station.

4. The vehicle-road cooperative signal priority control method according to claim 1, characterized in that: The time required for the bus to catch up with the middle point of the previous bus phase when the preceding signal phase is extended is calculated as: Calculate the time required for the bus to catch up with the next bus phase midpoint when the bus arrives at the intersection when the preceding signal phase is compressed: Wherein, Δt1 is the time required for the bus to catch up with the middle point of the last bus phase in the forward direction when the current sequence phase is extended, Δt2 is the time required for the bus to catch up with the middle point of the first bus phase in the backward direction when the current sequence phase is shortened, and c is the total duration of one phase cycle of the signal light; c g is the green light duration of each bus phase; t1 is the time difference between the current phase and the starting point of the next bus phase, and mod is the remainder operation; when or There is no need to compress or boost the phase of the preamble signal.

5. The vehicle-road cooperative signal priority control method according to claim 1, characterized in that: Also includes: Calculate the minimum green light duration in any phase of the traffic light; The minimum green light duration in the i-th phase of the traffic light is: Among them, G i人 is the minimum time for pedestrians to cross the street safely in the i-th phase; k is the maximum value of the total number of vehicles queuing in all directions at the intersection in the i-th phase in the previous cycle, and h j is the headway time of the jth vehicle, and t is the bus start loss time.

6. The vehicle-road cooperative signal priority control method according to claim 5, characterized in that: Calculate the maximum compression time and maximum extension time of the signal light phase according to the minimum green light duration of the signal light phase; The maximum compression time is: The minimum compression time is: Among them, C i is the phase duration of the i-th cycle of the signal light, C imax is the maximum duration of the i-th cycle of the signal light, G imin is the minimum green light duration of the i-th phase, p is the total number of cycles from the current time to the bus arriving at the intersection, G i is the green light duration of the i-th phase.

7. The vehicle-road cooperative signal priority control method according to claim 6, characterized in that: When Δt1>Δt + Or Δt2>Δt - When , a priority control strategy of compressing the phase of the preceding signal is adopted; When Δt1<Δt + Or Δt2>Δt - When , a priority control strategy of extending the phase of the preceding signal is adopted; When Δt1<Δt + And Δt2<Δt - ,as well as When the preamble signal is compressed, a control method combining the phase of the preamble signal with the speed of the bus is adopted; When Δt1<Δt + And Δt2<Δt - ,as well as When the bus is in a state of being ...

8. The vehicle-road cooperative signal priority control method according to claim 7, characterized in that: When the priority control strategy of compressing the phase of the preamble signal is selected, If max -t min ∈(C gmin ,C gmax ), the phase of the preamble signal that needs to be compressed or extended is: max(t min -t1-c,t max -t1-cc g ); Among them, t min is the starting time of the bus phase, t max is the end time of the bus phase; c gmin is the shortest green light duration for each bus phase, c gmax is the longest green light duration of each bus phase, t1 is the time difference between the current phase and the starting point of the next bus phase; When the phase of the preamble signal is compressed, the adjustment time of the phase duration is When the phase of the preamble signal is extended, the adjustment time of the phase duration is Among them, round means rounding to the nearest integer.

9. The vehicle-road cooperative signal priority control method according to claim 1, characterized in that: When the method of combining compressing the preceding signal phase with reducing the speed is selected, after calculating the signal light phase, the time when the bus is away from the intersection is: Δt=Δt2-Δt - ; Wherein, Δt is the time when the bus is away from the intersection after the phase of the preamble signal is compressed and the speed is reduced, Δt - is the maximum compression time of the signal light phase; Calculating boot speed Among them, v min The speed limit of the road section provides specific information based on the digital signs and markings; When the method of extending the phase of the preceding signal and increasing the speed is adopted, the time when the bus is away from the intersection after the phase of the signal light is extended is calculated as: Δt=Δt2-Δt - ; Calculating boot speed Among them, v max It is the speed limit value of the road section, and provides specific information based on the digital signs and markings.

10. A vehicle-road cooperative signal priority control system, implementing any vehicle-road cooperative signal priority control method as claimed in any one of claims 1 to 9, characterized in that: include: Data collection and perception system to collect traffic parameters; A vehicle information collection unit, used to transmit vehicle position information to a vehicle priority control unit; A vehicle priority control unit, used to determine whether the distance between the vehicle and the intersection is within a preset range, and when the distance between the vehicle and the intersection is within the preset range, send the position information of the vehicle to the calculation unit; A calculation unit, used for determining which bus priority control strategy to adopt according to the traffic parameters and the vehicle position information; The feedback unit is used to receive and execute the bus priority control strategy, and feed back the strategy execution status to the calculation unit.

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