A method for implementing multi-lane bus coordination priority

Abstract

The application provides a method for realizing multi-lane bus coordination priority, which can ensure the passing of high-priority bus vehicles at intersections while taking into account the passing demand of low-priority bus vehicles. First, a priority control phase queue is constructed based on minimum phase green; then, the green light backward movement interval of each phase of the priority control phase queue is calculated based on maximum phase green; next, for the bus vehicles requesting priority, a phase green light backward movement interval optimization model is established, which takes ensuring high-level bus priority as a prerequisite and takes into account low-level bus vehicle priority as a control target, and optimizes the green light backward movement interval of each release phase of the priority control phase queue in real time; finally, the green light release duration is calculated and output from the reasonable value of the phase green light backward movement interval. The output value of the application is the phase green light constraint interval, which can be converted into the phase green light release duration interval, so that the phase green light can be dynamically adjusted according to the actual traffic demand, and has great flexibility.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of urban traffic signal control, in particular to a method for realizing multi-route bus cooperative priority. BACKGROUND

[0002] Bus priority refers to giving bus vehicles more convenient priority right of passage relative to other social vehicles at an intersection by adopting a certain control strategy. In fine bus priority control, due to the influence of factors such as passenger capacity and bus delay time, there are differences in the priority passage levels between bus vehicles. When there are multiple bus vehicles requesting priority at an intersection, it is a common control method to select the bus vehicle with the highest priority passage level for priority service. If the priority passage of the bus vehicle with the high priority passage level is ensured, and the passage of the bus vehicle with the low priority passage level is taken into account, the travel efficiency of the bus vehicle will be greatly improved.

[0003] Therefore, it is of great significance to find a method for realizing multi-route bus cooperative priority. SUMMARY

[0004] The present application aims to provide a method for realizing multi-route bus cooperative priority, which takes into account the passage demand of the bus vehicle with the low priority level while serving the passage of the bus vehicle with the high priority level at the intersection.

[0005] The technical solution for realizing the present application is a method for realizing multi-route bus cooperative priority, comprising the following steps:

[0006] Step 1: constructing a priority control phase queue based on the minimum green phase;

[0007] Step 2: calculating the green light backward movement interval of each phase of the priority control phase queue based on the maximum green phase;

[0008] Step 3: establishing a green light backward movement interval optimization model for the bus vehicle requesting priority, which takes into account the priority of the bus vehicle with the low priority level as the control target on the premise of ensuring the priority of the bus vehicle with the high priority level, and optimizes the green light backward movement interval of each release phase of the priority control phase queue in real time; this part is divided into the following steps:

[0009] Step 3-1: constructing a set of bus vehicles to be served based on the bus vehicle requesting priority;

[0010] Step 3-2: selecting the bus vehicle with the highest priority from the set of bus vehicles to be served as the service bus;

[0011] Step 3-3: calculating the start demand extension and the end demand extension of the service bus phase in the priority control phase queue;

[0012] To realize the service bus passing through the intersection without stopping, based on the minimum green of each phase in the priority control phase queue, the green time of each phase is extended, and the end point of the green light of the bus phase is moved backward, so that the bus phase is in the green light state when the service bus is expected to arrive at the stop line. However, the allowed moving time of the end point of the green light of the bus phase is constrained by the green light moving interval of the bus phase. If the green light moving interval of the bus phase does not meet the requirement of releasing the bus phase when the bus is expected to arrive at the stop line, the minimum green of each phase is kept to release the bus phase after the service bus stops as soon as possible, and the red light time of the service bus is minimized;

[0013] Step 3-4, optimizing the green light moving interval of each released phase in the priority control phase queue;

[0014] Step 3-5, deleting the service bus from the set of to-be-served buses, and judging whether the set is empty. If yes, step 4 is executed, otherwise, step 3-2 is executed;

[0015] Step 4, calculating and outputting the green light release time of the phase from the green light moving interval.

[0016] Further, the priority control phase queue is constructed based on the minimum green of each phase in step 1, and the specific process includes:

[0017] Step 1-1, selecting the bus vehicle expected to arrive at the stop line latest from the buses requesting priority as the target bus vehicle for constructing the phase release queue;

[0018] Step 1-2, establishing an empty phase release queue, and adding phases to the phase release queue in a cycle according to the phase release sequence in the signal control, taking the phase being released as the starting phase, and taking the minimum green of each phase as the green light time of the phase, and accumulating and summing the green light time of the phase, until the accumulated value reaches the time when the target bus vehicle is expected to arrive at the stop line.

[0019] Step 1-3, taking the phase at the end of the phase release queue as the starting phase, and continuing to add the release phases of a signal control cycle, thereby forming the priority control phase queue.

[0020] Further, for the starting phase in the phase release queue, i.e. the phase being released, the minimum green needs to be corrected, and the correction method is: the minimum green is subtracted by the running green light time of the phase. However, if the running green light time of the starting phase exceeds the minimum green, the minimum green of the starting phase is set to 0.

[0021] Further, the green light moving interval of each phase in the priority control phase queue is calculated based on the maximum green of each phase in step 2, and the specific process includes:

[0022] Calculate the difference between the maximum and minimum green values ​​for each phase in the priority control phase queue to obtain the maximum allowable extension time for the phase; let m be the number of phases in the priority control phase queue, and let P be the i-th phase. i , 0 < i ≤ m, P i The minimum green is minT i P i The maximum green is maxT i Then P i The maximum allowable extension time is maxT i -minT i ;

[0023] Summation from initial phase P1 to phase P i The maximum permissible extension time is obtained by calculating the cumulative maximum permissible extension time for the first i phases, i.e., P. i The maximum time for the green light to end is shifted backward, from which P is obtained. i The green light shift interval is maxT j minT j Representing the j-th phase P j The maximum and minimum green.

[0024] Furthermore, in step 2-1, for the initial phase in the priority control phase queue, that is, the phase that is currently being released, its maximum green light needs to be corrected. The correction method is: the maximum green light minus the green light duration that the phase has been running.

[0025] Furthermore, the calculation of the initial and final demand extensions of the service bus phase in the priority control phase queue, as described in step 3-2, specifically includes:

[0026] In the priority control phase queue, the bus phase closest to the critical point before the expected arrival time of the bus at the stop line is selected as the target phase, with the critical point being the threshold.

[0027] When the target phase does not exist, it indicates that the bus phase that is expected to arrive at the stop line cannot be released. In this case, the bus phase closest to the critical point in the priority control phase queue is replaced with the target phase. The phase before the target phase is denoted as the target preceding phase. The initial demand extension of the service bus phase is output as [the lower limit of the green light shift interval of the target preceding phase, the lower limit of the green light shift interval of the target preceding phase], and the final demand extension is [the lower limit of the green light shift interval of the target phase, min{the upper limit of the green light shift interval of the target phase, the lower limit of the green light shift interval of the target preceding phase + the maximum allowable extension time of the target phase}]. Otherwise, the sub-queue from the starting phase to the target phase is selected as the sub-control queue, and the initial demand extension and final demand extension of the service bus phase are calculated respectively to make the target phase in the release state at the boundary point position.

[0028] Further, the calculation method of the start demand extension and the end demand extension of the service bus phase is as follows:

[0029] The minimum green accumulation of each phase of the sub-control queue is summed up, and the difference between the predicted arrival time of the service bus at the stop line and the minimum green accumulation is calculated as the minimum extension of the end demand of the service bus phase.

[0030] The maximum extension of the end demand of the service bus is obtained by using the minimum extension of the end demand and the maximum green of the target phase; if the minimum extension of the end demand of the service bus is less than or equal to 0, it means that the minimum green of each phase of the sub-control queue is running, so that the target phase is in the release state when the service bus is predicted to arrive at the stop line, and the value of the minimum extension of the end demand is 0; based on the above process, the end demand extension of the service bus phase is [minimum extension of the end demand, maximum extension of the end demand];

[0031] Then, it is judged whether the end demand extension of the service bus phase is within the allowed moving range of the target phase; if the minimum extension of the end demand of the service bus phase is greater than the upper limit of the moving constraint of the target phase or the maximum extension of the end demand of the service bus is less than the lower limit of the moving constraint of the target phase, it means that the bus phase cannot be released at the predicted arrival time of the bus at the stop line, so the nearest bus phase after the critical point in the priority phase queue is replaced by the target phase, the previous phase of the target phase is recorded as the target previous phase, the start demand extension of the service bus phase is output as [lower limit of the green light moving interval of the target previous phase, lower limit of the green light moving interval of the target previous phase], and the end demand extension is output as [lower limit of the green light moving interval of the target phase, min{upper limit of the green light moving interval of the target phase, lower limit of the green light moving interval of the target previous phase + maximum allowed extension time of the target phase}]; otherwise, the end demand extension of the service bus is output as [max{minimum extension of the end demand, lower limit of the green light moving interval of the target phase}, min{maximum extension of the end demand, upper limit of the green light moving interval of the target phase}], and the start demand extension of the service bus phase is further calculated.

[0032] It is judged whether the target phase is the start phase; if yes, the start demand extension of the service bus phase is output as [0, 0]; otherwise, the previous phase of the target phase is recorded as the target previous phase, and the calculation is performed as follows:

[0033] The minimum green accumulation sum of each phase except the target phase in the child control queue is calculated, and the difference between the service bus expected arrival time at the stop line and the above-mentioned accumulated value is calculated as the starting demand maximum extension of the service bus phase; the starting demand minimum extension of the service bus phase is obtained by using the starting demand maximum extension and subtracting the maximum green of the target phase; if the calculated starting demand minimum extension of the service bus is less than 0, it is corrected to 0; based on the above-mentioned method, the starting demand extension of the service bus phase is [starting demand minimum extension, starting demand maximum extension];

[0034] Then, it is judged whether the starting demand extension of the service bus phase is within the allowed backward shift range of the target front phase, if the starting demand minimum extension of the service bus phase is greater than the upper limit of the backward shift constraint of the target front phase or the ending demand maximum extension of the service bus phase is less than the lower limit of the backward shift constraint of the target front phase, the starting demand extension of the service bus phase is output as [lower limit of the green backward shift interval of the target front phase, lower limit of the green backward shift interval of the target front phase]; otherwise, the starting demand extension of the service bus phase is output as [max{starting demand minimum extension, lower limit of the green backward shift interval of the target front phase}, min{starting demand maximum extension, upper limit of the green backward shift interval of the target front phase}].

[0035] Further, the green backward shift interval of each release phase in the priority control phase queue is optimized according to the step 3-4, specifically including:

[0036] Let the green backward shift interval of the i-th phase P i be The service bus phase is P g , 1≤g≤m, the starting demand extension of the service bus phase is The ending demand extension of the service bus phase is

[0037] The calculation model of optimizing the green backward shift interval of each phase in the priority control phase queue based on the demand extension of the service bus phase is as follows:

[0038]

[0039]

[0040] Further, the green release time of each phase is calculated and output from the green backward shift interval according to the step 4, specifically including:

[0041] The green backward shift interval of each phase is executed, and the multi-route bus coordination priority can be realized.

[0042] Case 1: for the intersection without social vehicle detection equipment, the green light back-off interval selection algorithm is designed based on the principle of minimum impact on the basic background timing;

[0043] Case 2: for the intersection with social vehicle detection equipment, the phase green light back-off interval is allocated to each phase in the priority control phase queue according to the real-time traffic demand.

[0044] Further, for case 1, a simple green light back-off interval example selection method is given:

[0045] For the current phase P1, the value mbl is selected from the green light back-off interval of P1, so that the absolute value of the difference between (minT1+mbl) and the basic background release time T1 of P1 is minimum;

[0046] When the release of P1 is over and the phase is switched, the current phase is updated and the above process is repeated;

[0047] For case 2, a green light back-off interval example dynamic selection method under inductive control is given:

[0048] The green light release constraint interval of the current phase P1 is calculated as The inductive control algorithm is executed based on the green light release constraint interval;

[0049] When the release of P1 is over and the phase is switched, the current phase is updated and the above process is repeated.

[0050] Compared with the prior art, the present application has the following advantages:

[0051] 1) The multi-route bus cooperative priority implementation method proposed in the present application first selects high-priority buses as service vehicles, calculates the phase green light back-off interval for priority passage, and then on this basis, priority service is provided to other buses with lower priority, so that the method ensures the priority passage right of high-priority buses, while taking into account the passage demand of low-priority buses.

[0052] 2) The method proposed in the present application realizes multi-route bus cooperative priority, and the output value is the phase green light constraint interval, which can be converted into the phase green light release time interval, so that the phase green light can be dynamically adjusted according to the actual traffic demand, and has great flexibility.

[0053] The present application will be described in further detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0054] Figure 1 The flowchart of the multi-route bus cooperative priority implementation method of the present application.

[0055] Figure 2For a four-phase period example in one embodiment, wherein Figure 2 (a) to (d) in the figure are phase 1 (P1): straight north-south, phase 2 (P2): left turn north-south, phase 3 (P3): straight east-west, and phase 4 (P4): left turn east-west. DETAILED DESCRIPTION

[0056] In order to make the purposes, technical solutions and advantages of the present application clearer, the present application is further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and not to limit the present application.

[0057] The present application proposes a method for implementing multi-lane bus coordination priority, aiming to prioritize high-level bus vehicles passing through intersections while taking into account the passing needs of low-level bus vehicles. Figure 1 , specifically comprising the following steps:

[0058] Step 1: initialization of control parameters

[0059] The control parameters are initialized as needed, including the minimum green of the phase, the basic time length, the maximum green, etc.

[0060] Step 2: constructing a priority control phase queue based on the minimum green of the phase

[0061] First, select the bus vehicle that is expected to arrive at the stop line the latest from the buses requesting priority as the target bus vehicle for constructing the phase release queue; then, establish an empty phase release queue, take the phase that is currently being released as the starting phase, and add phases to the queue in the order of the cycle phase release sequence in signal control, take the minimum green of each phase as its green time length, and add the green time lengths of the phases to obtain the sum, until the sum reaches the time when the buses in the queue are expected to arrive at the stop line; finally, take the last phase in the queue as the starting phase and continue to add a release phase for one signal control cycle.

[0062] For the starting phase in the phase release queue, i.e., the phase that is currently being released, the minimum green needs to be modified, and the modification method is to subtract the green time length of the phase that has been running from the minimum green. However, if the green time length of the starting phase that has been released exceeds the minimum green, the minimum green is set to 0.

[0063] Step 3: calculating the green light shift interval of each phase in the priority control phase queue based on the maximum green of the phase

[0064] First, calculate the difference between the maximum green and the minimum green of each phase in the priority control phase queue to obtain the maximum allowed extension time of the phase. However, for the starting phase in the priority control phase queue, i.e., the phase that is currently being released, the maximum green needs to be modified, and the modification method is to subtract the green time length of the phase that has been running from the maximum green.

[0065] Let m be the number of phases in the priority control phase queue, and let P be the i-th phase. i , 0 < i ≤ m, P i The minimum green is minT i P i The maximum green is maxT i Then P i The maximum allowable extension time is maxT i -minT i ;

[0066] Summation from initial phase P1 to phase P i The maximum permissible extension time is obtained by calculating the cumulative maximum permissible extension time for the first i phases, i.e., P. i The maximum time for the green light to end is shifted backward, from which P is obtained. i The green light shift interval is maxT j minT j Representing the j-th phase P j The maximum and minimum green.

[0067] Step 4: Establish an optimization model for the green light shift interval of each phase in the priority control phase queue, and optimize the green light shift interval of each phase in real time.

[0068] For buses requesting priority, an optimization model for the green light shift interval is established. This model aims to ensure priority for high-priority buses while also taking into account the priority of low-priority buses. It optimizes the green light shift interval of each release phase in the priority control phase queue in real time. This part is further divided into the following steps.

[0069] Step 4-1: Construct a set of buses to be served based on the buses with priority in requesting services;

[0070] Step 4-2: Select the highest priority vehicle from the set as the service bus;

[0071] Step 4-3: Calculate the initial demand extension and the final demand extension of the service bus phase in the queue;

[0072] In the priority control phase queue, the critical point is the time when the service bus is expected to arrive at the stop line. The nearest bus phase before the critical point is selected as the target phase. When the target phase does not exist, it means that the bus phase cannot be released at the time when the service bus is expected to arrive at the stop line. The nearest bus phase after the critical point in the priority control phase queue is replaced as the target phase. The previous phase of the target phase is recorded as the target previous phase. The starting demand extension of the service bus phase is [the lower limit of the green light rear movement interval of the target previous phase, the lower limit of the green light rear movement interval of the target previous phase], and the ending demand extension is [the lower limit of the green light rear movement interval of the target phase, min{the upper limit of the green light rear movement interval of the target phase, the lower limit of the green light rear movement interval of the target previous phase + the maximum allowed extension time of the target phase}]. Otherwise, the sub-control queue is selected from the sub-queue from the starting phase to the target phase, and the starting demand extension and the ending demand extension of the service bus phase are calculated when the target phase is in the release state at the boundary point.

[0073] The calculation method of the starting demand extension and the ending demand extension of the service bus phase is as follows:

[0074] Firstly, the minimum green accumulation of each phase in the sub-control queue is summed up, and the difference between the time when the service bus is expected to arrive at the stop line and the above-mentioned accumulated value is calculated as the minimum extension of the ending demand of the service bus phase. Then, the maximum green of the target phase is added to the above-mentioned minimum extension to obtain the maximum extension of the ending demand of the service bus. If the minimum extension of the ending demand of the service bus is less than or equal to 0, it means that the minimum green of each phase in the sub-control queue is running, i.e. the target phase can be in the release state at the time when the service bus is expected to arrive at the stop line. At this time, the minimum extension of the ending demand is 0. Based on the above-mentioned method, the ending demand extension of the service bus phase is [the minimum extension of the ending demand, the maximum extension of the ending demand].

[0075] Then, it is judged whether the end demand extension of the service bus phase is within the allowed range of the target phase. If the minimum extension of the end demand of the service bus phase is greater than the upper limit of the target phase or the maximum extension of the end demand of the service bus is less than the lower limit of the target phase, it is indicated that the bus cannot be released at the predicted arrival time of the stop line, and the target phase is replaced by the nearest bus phase after the critical point in the priority control phase queue, the previous phase of the target phase is recorded as the target previous phase, the start demand extension of the service bus phase is output as [the lower limit of the green light moving interval of the target previous phase, the lower limit of the green light moving interval of the target previous phase], and the end demand extension of the service bus phase is output as [the lower limit of the green light moving interval of the target phase, min{the upper limit of the green light moving interval of the target phase, the lower limit of the green light moving interval of the target previous phase + the maximum allowed extension time of the target phase}]. Otherwise, the end demand extension of the service bus is output as [max{the minimum extension of the end demand, the lower limit of the green light moving interval of the target phase}, min{the maximum extension of the end demand, the upper limit of the green light moving interval of the target phase}], and the start demand extension of the service bus phase is further calculated. It is judged whether the target phase is the start phase. If yes, the start demand extension of the service bus phase is output as [0, 0]; otherwise, the previous phase of the target phase is recorded as the target previous phase, and the calculation is performed by using the following method.

[0076] Firstly, the minimum green light of each phase in the sub-control queue except the target phase is summed up, the difference between the predicted arrival time of the service bus at the stop line and the above-mentioned sum is calculated as the maximum extension of the start demand of the service bus phase, and the maximum extension is subtracted from the maximum green light of the target phase to obtain the minimum extension of the start demand of the service bus phase. If the calculated minimum extension of the start demand of the service bus is less than 0, it is corrected to 0. Based on the above-mentioned method, the start demand extension of the service bus phase is [the minimum extension of the start demand, the maximum extension of the start demand].

[0077] Then, it is judged whether the start demand extension of the service bus phase is within the allowed range of the target previous phase. If the minimum extension of the start demand of the service bus phase is greater than the upper limit of the target previous phase or the maximum extension of the end demand of the service bus phase is less than the lower limit of the target previous phase, the start demand extension of the service bus phase is output as [the lower limit of the green light moving interval of the target previous phase, the lower limit of the green light moving interval of the target previous phase]; otherwise, the start demand extension of the service bus phase is output as [max{the minimum extension of the start demand, the lower limit of the green light moving interval of the target previous phase}, min{the maximum extension of the start demand, the upper limit of the green light moving interval of the target previous phase}].

[0078] Step 4-4, optimizing the green light moving interval of each release phase in the priority control phase queue;

[0079] Record P i The green light backoff interval of the service bus phase is The service bus phase is P g , 1≤.g≤m, the starting demand extension of the service bus phase is The ending demand extension of the service bus phase is The calculation model of the green light backoff interval of each phase of the priority control phase queue based on the demand extension of the service bus phase is constructed as follows.

[0080]

[0081]

[0082] Step 4-5, the service bus is deleted from the set, and it is judged whether the set is empty, if yes, step 5 is executed, otherwise, step 4-2 is executed;

[0083] Step 5: a reasonable value is selected from the phase green light backoff interval to calculate and output the green light release duration

[0084] Each phase of the green light backoff interval arbitrary value is executed, and the multi-way bus coordination priority can be realized. For the intersection lacking the social vehicle detection device, the green light backoff interval selection algorithm can be designed based on the principle of minimum impact on the basic background timing; for the intersection with the social vehicle detection device, the phase green light backoff interval can be distributed to each phase in the priority control phase queue according to the real-time traffic demand.

[0085] For the former, the application gives a simple example of the green light backoff interval selection method, for the current phase P1, a value mbl is selected from the green light backoff interval of P1, so that the absolute value of the difference between (minT1+mbl) and the basic background release duration T1 of P1 is minimum. When the release of P1 ends and the phase is switched, the current phase is updated, and the above green light backoff interval selection method is repeated.

[0086] For the latter, the application gives a dynamic example of the green light backoff interval selection method under the induction control, and the green light release constraint interval of the current phase P1 is calculated as The induction control algorithm is executed based on the above green light release constraint interval. When the release of P1 ends and the phase is switched, the current phase is updated, and the above green light backoff interval selection method is repeated.

[0087] The application will be further verified and described in combination with specific embodiments.

[0088] Embodiment

[0089] Taking the four-phase cycle in Figure 2 as an example, the minimum green average of each phase is 15s, the maximum green average is 25s, and the basic duration is 20s.

[0090] Assume that there are two buses at the beginning of the release of phase P1, i.e., at the time of 0s of the green release of P1, the bus1 with high priority is expected to arrive at the stop line for 75s, and its request phase is P4, and the bus2 with low priority is expected to arrive at the stop line for 36s, and its request phase is P2.

[0091] Constructing a queue of priority control phases Let the cumulative value of the minimum green of each phase in the release queue be a; P1 currently being released is added to the queue as the starting phase, at this time, a = 15s; since the condition that a is greater than or equal to the bus1 expected arrival time at the stop line 75s is not met, P2 is added to the queue according to the phase release order shown in Figure 2 , at this time, a = 15 + 15 = 30s; similarly, the phase is added to the queue according to the phase release order shown in Figure 2 , until the condition that a ≥ 75s is met, at this time, a = 15 + 15 + 15 + 15 + 15 = 75s; finally, the release phase of one signal control cycle is added to the queue starting from the end P1, and finally,

[0092] Based on the maximum green of each phase, the green light shift interval of each phase is calculated, for convenience of description, the phases in are numbered, let where the subscript is the sequence number of the phase in the queue, and the superscript is the actual number of the phase. Then the green light shift interval of each phase in is [0, 10], [0, 20], [0, 30], [0, 40], [0, 50], [0, 60], [0, 70], [0, 80] in turn.

[0093] A set of buses to be served σ = {bus1, bus2} is constructed, and bus1 with high priority is selected as the service bus, and the starting demand extension and the ending demand extension in the queue are calculated.

[0094] Take the bus1 expected arrival time at the stop line 75s as the critical point, and select the nearest bus phase before the critical point as the target phase. The sum of the minimum green of is 60s, and the ending demand minimum extension of is 75-60 = 15s; then, the maximum green of is added to the above minimum extension to obtain the ending demand maximum extension of 40s; thus,The end-of-demand extension is [15, 40]. The minimum green summation is 45s. Calculate... The initial maximum extension is 75-45=30s; subtract the above maximum extension from... The maximum green, obtained The minimum extension required at the beginning is 5 seconds; therefore, it is concluded that... The initial demand extension is [5, 30].

[0095] Using a calculation model that optimizes the green light shift interval for each phase of the priority control phase queue, the green light shift interval for each phase is adjusted to obtain... The green light shift intervals for each phase are [0, 10], [0, 20], [5, 30], [15, 40], [15, 50], [15, 60], [15, 70], and [15, 80].

[0096] Remove bus1 from σ. At this point, σ = {bus2}. Select bus3 as the service bus and calculate its initial demand extension and final demand extension in the queue.

[0097] Using the estimated arrival time of bus2 at the stop line in 36 seconds as the critical point, select the nearest bus phase before the critical point. As the target phase. For The minimum green summation is 30s. Calculate... The minimum extension required to finish is 36-30=6s; then, add the above minimum extension to... The maximum green, obtained The maximum extension of the end requirement is 31 seconds; at this point, it is concluded that... The end-of-demand extension is [6, 31], affected by Green light shift interval [0, 20] constraint, correction The end-of-demand extension is [6, 20]. For The minimum green summation is 15s. Calculate... The initial maximum extension is 36 - 15 = 21 seconds; subtract the above maximum extension from... The maximum green, obtained The minimum extension of the initial demand is -4s; therefore, it is concluded that... The initial demand extension is [-4, 21], affected by Green light shift interval [0, 10] constraint, correction The initial demand extension is [0, 10].

[0098] Using a calculation model that optimizes the green light shift interval for each phase of the priority control phase queue, the green light shift interval for each phase is adjusted to obtain... The green light shift intervals for each phase are [0, 10], [6, 20], [6, 30], [15, 40], [15, 50], [15, 60], [15, 70], and [15, 80].

[0099] Remove bus2 from σ. At this point... Select a reasonable value from the phase green light shift interval, calculate and output its green light duration.

[0100] If the intersection lacks social vehicle detection equipment, based on For a base background timing of 20 seconds, select 5 from the green light shift interval [0, 10] and output. The green light duration is 15 + 5 = 20 seconds; After the passage is completed, the algorithm is executed again to output the green light duration for the next phase.

[0101] If there are vehicle detection devices at the intersection and the control mode is sensor-based, adjust the current phase. The green light release constraint range is [15+0, 15+10], and sensor control is performed based on the above green light release constraint range. After the passage is completed, the algorithm is executed again to adjust the green light passage constraint range for the next phase.

[0102] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention without departing from its spirit and scope should be included within the protection scope of the present invention.

Claims

1. A method for implementing multi-route bus coordination priority, characterized in that, The method includes the following steps: Step 1: Construct a priority control phase queue based on the green with the smallest phase; Step 2: Calculate the green light shift interval for each phase in the priority control phase queue based on the maximum green light of the phase; Step 3: For buses requesting priority, establish an optimization model for the green light shift interval of the phase. This model takes ensuring the priority of high-level buses as a premise and taking into account the priority of low-level buses as a control objective, and optimizes the green light shift interval of each release phase in the priority control phase queue in real time. This part is divided into the following steps. Step 3-1: Construct a set of buses to be served based on the buses with priority in requesting services; Step 3-2: Select the highest priority vehicle from the set of buses to be served as the serving bus; Step 3-3: Calculate the initial demand extension and the final demand extension of the service bus phase in the priority control phase queue; Steps 3-4: Optimize the green light shift interval for each release phase in the priority control phase queue; Steps 3-5: Remove the serving buses from the set of buses to be served, and determine whether the set is empty. If it is, proceed to step 4; otherwise, proceed to step 3-2. Step 4: Select any value from the phase green light shift interval, calculate and output its green light duration.

2. The method for implementing multi-route bus cooperative priority according to claim 1, characterized in that, Step 1, which involves constructing a priority control phase queue based on the minimum green phase, specifically includes the following process: Step 1-1: Select the bus that is expected to arrive at the stop line last from the buses requesting priority as the target bus for building the phase release queue; Step 1-2: Establish an empty phase release queue. Starting with the phase currently being released, add phases to the phase release queue in a cyclical manner according to the periodic phase release order in signal control. Take the minimum green light duration of each phase as its green light duration, and sum the green light durations of the phases until the sum reaches the expected arrival time of the target bus at the stop line. Steps 1-3: Starting with the last phase of the phase release queue, add a release phase for one signal control cycle to form a priority control phase queue.

3. The method for implementing multi-route bus cooperative priority according to claim 2, characterized in that, For the initial phase in the phase release queue, i.e. the phase that is currently being released, its minimum green light needs to be corrected. The correction method is: minimum green light minus the green light duration already in operation for the phase; however, if the green light duration already in operation for the initial phase exceeds the minimum green light, then its minimum green light is set to 0.

4. The method for implementing multi-route bus cooperative priority according to claim 1, characterized in that, Step 2, which calculates the green light shift interval for each phase in the priority control phase queue based on the maximum green light of the phase, specifically includes the following process: Calculate the difference between the maximum and minimum green values ​​for each phase in the priority control phase queue to obtain the maximum allowable extension time for the phase; let m be the number of phases in the priority control phase queue, and let P be the i-th phase. i 0 <i≤m,P i The minimum green is minT i P i The maximum green is maxT i Then P i The maximum allowable extension time is maxT i -minT i ; Summation from initial phase P1 to phase P i The maximum permissible extension time is obtained by calculating the cumulative maximum permissible extension time for the first i phases, i.e., P. i The maximum time for the green light to end is shifted backward, from which P is obtained. i The green light shift interval is maxT j minT j Representing the j-th phase P j The maximum and minimum green.

5. The method for implementing multi-route bus cooperative priority according to claim 4, characterized in that, In step 2-1, for the starting phase in the priority control phase queue, that is, the phase that is currently being released, its maximum green light needs to be corrected. The correction method is: the maximum green light minus the green light duration that the phase has been running.

6. The method for implementing multi-route bus cooperative priority according to claim 4, characterized in that, Step 3-2, which involves calculating the initial and final demand extensions of the service bus phase within the priority control phase queue, specifically includes the following process: In the priority control phase queue, the bus phase closest to the critical point before the expected arrival time of the bus at the stop line is selected as the target phase, with the critical point being the threshold. When the target phase does not exist, it indicates that the bus phase that is expected to arrive at the stop line cannot be released. In this case, the bus phase closest to the critical point in the priority control phase queue is replaced with the target phase. The phase before the target phase is denoted as the target preceding phase. The initial demand extension of the service bus phase is output as [the lower limit of the target preceding phase's green light shift interval, the upper limit of the target preceding phase's green light shift interval], and the final demand extension is [the lower limit of the target phase's green light shift interval, min{the upper limit of the target phase's green light shift interval, the lower limit of the target preceding phase's green light shift interval + the target phase's maximum allowable extension time}]. Otherwise, the sub-queue from the starting phase to the target phase is selected as the sub-control queue, and the initial demand extension and final demand extension of the service bus phase are calculated respectively to make the target phase in the release state at the boundary point position.

7. The method for implementing multi-route bus cooperative priority according to claim 6, characterized in that, The calculation method for the initial and final demand extensions of the service bus phase is as follows: The minimum green summation of each phase in the sub-control queue is calculated, and the difference between the estimated arrival time of the service bus at the stop line and the minimum green summation value is used as the minimum extension of the service bus phase's end demand. The maximum extension of the service bus's end demand is obtained by adding the minimum extension amount of the end demand to the maximum green of the target phase. If the minimum extension amount of the service bus's end demand is less than or equal to 0, it means that each phase of the sub-control queue is running at the minimum green, which can make the target phase in the release state when the service bus is expected to arrive at the stop line. At this time, the minimum extension amount of the end demand is 0. Based on the above process, the extension amount of the service bus phase's end demand is obtained as [minimum extension amount of end demand, maximum extension amount of end demand]; Then, it is determined whether the extension amount of the service bus phase's end demand is within the allowable backward movement range of the target phase. If the minimum extension amount of the service bus phase's end demand is greater than the upper limit of the target phase's backward movement constraint, or the maximum extension amount of the service bus phase's end demand is less than the lower limit of the target phase's backward movement constraint, it indicates that the bus phase cannot be released at the expected arrival time of the bus at the stop line. In this case, the bus phase closest to the critical point in the priority control phase queue is replaced with the target phase. The phase before the target phase is denoted as the target front phase. The initial demand extension amount of the service bus phase is output as [lower limit of the target front phase's green light backward movement interval, lower limit of the target front phase's green light backward movement interval], and the end demand extension amount is [lower limit of the target phase's green light backward movement interval, min{upper limit of the target phase's green light backward movement interval, lower limit of the target front phase's green light backward movement interval + maximum allowable extension time of the target phase}]. Otherwise, the end demand extension amount of the service bus phase is output as [max{minimum extension amount of end demand, lower limit of the target phase's green light backward movement interval}, min{maximum extension amount of end demand, upper limit of the target phase's green light backward movement interval}], and the initial demand extension amount of the service bus phase is further calculated. Determine if the target phase is the starting phase. If so, output the starting demand extension of the service bus phase as [0, 0]. Otherwise, denote the phase preceding the target phase as the target preceding phase and calculate it using the following method: The minimum green values ​​of all phases in the sub-control queue, excluding the target phase, are summed. The difference between the estimated arrival time of the serving bus at the stop line and the summed value is used as the maximum initial demand extension for the serving bus phase. The maximum initial demand extension is then subtracted from the maximum green value of the target phase to obtain the minimum initial demand extension for the serving bus phase. If the calculated minimum initial demand extension is less than 0, it is corrected to 0. Based on the above method, the initial demand extension for the serving bus phase is obtained as [minimum initial demand extension, maximum initial demand extension]; Then, it is determined whether the initial demand extension of the service bus phase is within the allowable backward movement range of the target preceding phase. If the minimum initial demand extension of the service bus phase is greater than the upper limit of the backward movement constraint of the target preceding phase or the maximum final demand extension of the service bus phase is less than the lower limit of the backward movement constraint of the target preceding phase, the initial demand extension of the service bus phase is output as [lower limit of the green light backward movement interval of the target preceding phase, lower limit of the green light backward movement interval of the target preceding phase]; otherwise, the initial demand extension of the service bus phase is output as [max{minimum initial demand extension, lower limit of the green light backward movement interval of the target preceding phase}, min{maximum initial demand extension, upper limit of the green light backward movement interval of the target preceding phase}].

8. The method for implementing multi-route bus cooperative priority according to claim 7, characterized in that, Steps 3-4, which optimize the green light shift interval for each release phase in the priority control phase queue, specifically include: Let the i-th phase P be... i The green light shift interval is The service bus phase is P g ,1≤g≤m, the initial demand extension of the service bus phase is The extension of the end-of-phase demand for bus services is The calculation model for optimizing the green light shift interval of each phase in the priority control phase queue based on the demand extension of the service bus phase is as follows:

9. The method for implementing multi-route bus cooperative priority according to claim 8, characterized in that, Step 4, which involves selecting any value from the phase green light shift interval to calculate and output its green light duration, specifically includes: Scenario 1: For intersections lacking social vehicle detection equipment, an algorithm for selecting the green light shift interval is designed based on the principle of minimizing the impact on the basic background timing. Scenario 2: For intersections with social vehicle detection equipment, the green light phase shift interval is allocated to each phase in the priority control phase queue according to real-time traffic demand.

10. The method for implementing multi-route bus cooperative priority according to claim 9, characterized in that, For case 1, the algorithm for selecting the green light shift interval is as follows: For the current phase P1, from its green light shift interval Choose the value mbl to minimize the absolute value of the difference between (minT1+mbl) and the basic background release time T1 of P1; After P1 releases the passage and the phase switching is completed, update the current phase and repeat the above process; For scenario 2: Calculate the green light release constraint interval for the current phase P1 as follows: The sensor control algorithm is executed based on the green light restriction range. After P1 releases the passage and switches phases, update the current phase and repeat the above process.

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