A method and system for defining "empty release" to evaluate the efficiency of road intersection scheduling

Abstract

The present invention provides a method and system for defining "empty release" to evaluate the dispatching efficiency of road intersections, including: defining empty release, creating a mapping table qMapTV and an empty release data item list of the duration of the current phase and the corresponding total number of outgoing vehicles in the evaluation system, calculating the duration S of the current phase, counting the total number of all outgoing vehicles in the release process of the current phase as N, generating a data group M, and recording it in the mapping table qMapTV; the evaluation system traverses the mapping table data group in real time to see if it meets the empty release; creates a new empty release data item and stores it in the empty release data item list; when the traffic command system has sent the next phase switching signal, the current phase ends, calculates whether the empty release index of the current phase meets the overall empty release, and feeds back the currently stored empty release data item list and the overall empty release data to the traffic command system. Beneficial effects of the present invention: the evaluation method is simple, the dispatching efficiency evaluation of road intersections is highly accurate, and real-time feedback can be achieved.

Description

Technical Field

[0001] The present invention relates to a traffic assessment method, and in particular to a method and system for defining "empty release" to assess the efficiency of road intersection scheduling. Background Art

[0002] With the continuous development of the national economy, the country's urbanization has also been developing continuously. The density of urban roads has been increasing. The urban population is increasing, the traffic on urban roads is also increasing, and the problem of urban road congestion is becoming increasingly prominent.

[0003] Although Internet technology has developed rapidly, the problem of urban road congestion has not been well solved by relying on Internet technology. Urban road resources are limited, and the travel of urban population is irregular and unplanned. The current strategy to solve the problem of urban road congestion is mainly focused on restricting vehicle travel. However, since people's travel cannot be effectively controlled by vehicle restrictions, the flow of people traveling cannot be well controlled.

[0004] In other cases, when various emergencies occur in cities and require emergency treatment, such as when 120 ambulances need to rush to the rescue site as quickly as possible, or when people in critical condition need to be sent to the hospital as quickly as possible in daily life, urban traffic is often the biggest constraint. In particular, the signal control at each road intersection needs to ensure that each direction of vehicle entry is as smooth as possible, allocating more green light time in the direction with more traffic, and less green light time in the direction with less traffic.

[0005] However, at present, when optimizing the signal timing at road intersections, the existing evaluation and scheduling schemes generally adjust the duration of traffic lights according to the congestion situation over a period of time. The algorithm has large errors and low effectiveness, and the evaluation feedback is slow. It usually takes several traffic light cycles to provide feedback, and it is impossible to provide real-time feedback on the scheduling efficiency of road intersections. Summary of the invention

[0006] In order to solve the problems in the prior art, the present invention provides a method and system for defining "empty traffic" to evaluate the dispatching efficiency of road intersections. By defining empty traffic, the traffic conditions of road intersections are evaluated in real time, and the dispatching efficiency of road intersections is calculated according to the empty traffic index, and then real-time feedback is given to the traffic command system. The evaluation method is simple, the dispatching efficiency of road intersections is evaluated with high accuracy, and real-time feedback can be achieved. After each phase is completed, the list of empty traffic data items and the overall empty traffic data of the road intersection are fed back to the traffic command system once, and the evaluation feedback speed is fast, which solves the problems of large errors, low effectiveness and slow evaluation feedback in the algorithm for evaluating the dispatching scheme in the prior art.

[0007] A method and system for defining "empty release" to evaluate the efficiency of road intersection scheduling of the present invention comprises the following steps:

[0008] Step 1: Define an empty release in the evaluation system. If the total number of vehicles leaving the vehicle in each sub-direction released in this phase does not exceed m for n consecutive seconds, it is recorded as an empty release.

[0009] Step 2: Phase start, save the start time tmG of this phase, create a mapping table qMapTV of the duration of this phase and the corresponding total number of vehicles leaving and a list of empty release data items in the evaluation system;

[0010] Step 3: Calculate the duration S of the release in this phase, count the total number of vehicles leaving all lanes with green lights during the release process in this phase as N, generate a data group M storing S and N, and record it in the mapping table qMapTV;

[0011] Step 4: The evaluation system compares the values ​​of S and n in real time. When S>n, it traverses all data groups in the mapping table qMapTV from the beginning to the end except for the last data group.

[0012] Step 5: If the current data group is Mi, traverse each data group in the mapping table qMapTV one by one from the data group after the data group Mi to the end; if the current data group is Mj, when Sj-Si≥n and Nj-Ni<m, the number of empty release records p in this phase is executed once p=p+1;

[0013] Step 6: Traverse all data groups in the mapping table qMapTV one by one from the beginning to the end until the current data group Mk is Mj, and delete the above data group from the mapping table qMapTV;

[0014] Step 7: Create a new empty data item and store it in the empty data item list;

[0015] Step 8: The evaluation system monitors in real time whether the traffic control system has sent the next phase switching signal;

[0016] Step 9: When the evaluation system monitors in real time that the traffic control system has sent the next phase switching signal, the current phase is ended, and the empty release index of the current phase is calculated and determined whether it meets the overall empty release, and the currently stored empty release data item list and the overall empty release data are fed back to the traffic control system.

[0017] The present invention is further improved. In step 1, n and m are both natural numbers, the value range of n is 2≤n≤10, and the value range of m is 0≤m≤5.

[0018] The present invention is further improved. In step 3, the duration S of the release of the current phase is the difference between the current time and the start time tmG of the current phase, S is a positive integer, and N is a natural number.

[0019] The present invention is further improved. In step 5, i, j, and p are all natural numbers, and the total duration of the idle discharge in this phase is the product of the number of idle discharge records p in this phase and the idle discharge time n of each phase.

[0020] The present invention is further improved, in step 6, k is a natural number, and the data groups deleted from the mapping table qMapTV are all data groups that have been traversed in the mapping table qMapTV.

[0021] The present invention is further improved. In step 7, the idle release data item stores the phase time (Si) at the beginning and the phase time (Sj) at the end of the idle release of this phase, as well as the corresponding total number of outgoing vehicles Ni and Nj.

[0022] The present invention is further improved. In step 8, when the evaluation system monitors in real time that the traffic control system does not send the next phase switching signal, step 3 is executed.

[0023] The present invention is further improved. In step 9, the total duration t of the current phase is calculated, and the total number of vehicles q that drive out during the release of the current phase is calculated. When q<Q and q / t<v, it is determined that the current phase meets the overall empty release. The value range of Q is 0≤Q≤10, Q is a natural number, and the value range of v is 0≤v≤0.5.

[0024] The present invention is further improved, the total duration t of this phase is the difference between the current time of ending this phase and the start time tmG of this phase, t is a natural number, when this phase meets the overall empty release, the empty release duration of this phase is directly the total duration t of this phase.

[0025] The present invention also provides a system for implementing the above-mentioned method for defining "empty release" to evaluate the dispatching efficiency of road intersections, comprising:

[0026] The phase basic data acquisition module is used to obtain the phase basic data of the traffic control system, including obtaining the duration S of the release of the current phase, obtaining the total number N of vehicles leaving all green light lanes during the release of the current phase; and is used to monitor in real time whether the traffic control system has sent the next phase switching signal;

[0027] The empty release index evaluation and calculation module is used to create a mapping table qMapTV and an empty release data item list of the duration of the current phase and the corresponding total number of vehicles leaving in the evaluation system; to generate a data group M storing S and N, and record it in the mapping table qMapTV; to compare the values ​​of S and n in real time, and when S>n, traverse all data groups in the mapping table qMapTV from the beginning to the end except the last data group; to traverse each data group in the mapping table qMapTV from the next data group of the data group Mi to the end; if the current data group is Mj, then when Sj-Si≥n and Nj-Ni<m, the empty release record number p of this phase is executed once p=p+1; to traverse all data groups in the mapping table qMapTV from the beginning to the end until the current data group Mk is Mj, and delete the above data group from the mapping table qMapTV; to end the current phase when it is monitored in real time that the traffic control system has sent the next phase switching signal, and calculate and judge whether the empty release index of this phase meets the overall empty release;

[0028] The statistics and feedback module is used to create a new empty release data item and store it in the empty release data item list; it is used to feed back the currently stored empty release data item list and the overall empty release data to the traffic control system.

[0029] The beneficial effects of the present invention are as follows: the present invention provides a method and system for defining "empty release" to evaluate the dispatching efficiency of a road intersection. By defining empty release to evaluate the traffic conditions of the road intersection in real time, and calculating the dispatching efficiency of the road intersection based on the empty release index, real-time feedback is then given to the traffic control system. The evaluation method is simple, the dispatching efficiency evaluation of the road intersection is highly accurate, and real-time feedback can be achieved. After each phase is completed, the list of empty release data items and the overall empty release data of the road intersection are fed back to the traffic control system once. The evaluation feedback speed is fast, which solves the problems of large errors, low effectiveness, and slow evaluation feedback in the algorithm for evaluating the dispatching scheme in the prior art. Moreover, in the evaluation over a longer period of time, such as multiple phases or multiple traffic light cycles, the overall empty release can also be used to evaluate the dispatching efficiency of the road intersection in each phase during this period of time. In the long-term evaluation of the dispatching efficiency of the road intersection, it is more accurate overall. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 A flowchart of a method for defining "empty release" to evaluate the efficiency of road intersection scheduling according to the present invention;

[0031] Figure 2 A block diagram of an evaluation system for defining a method for evaluating the dispatch efficiency of road intersections by using an "empty release" method for the implementation of the present invention. DETAILED DESCRIPTION

[0032] The present invention is further described in detail below with reference to the accompanying drawings and embodiments.

[0033] See also Figure 1 A method and system for defining "empty release" to evaluate the efficiency of road intersection scheduling of the present invention comprises the following steps:

[0034] Step 1: Define empty release in the evaluation system. If the total number of vehicles driving out of each sub-direction released in this phase does not exceed m for n consecutive seconds, it is recorded as an empty release, where n and m are both natural numbers, n has a value range of 2≤n≤10, and m has a value range of 0≤m≤5. In this embodiment, an indicator called "empty release" is defined in the evaluation system to evaluate the scheduling efficiency and the calculation of empty release records in this phase over a period of time. In this way, the number of empty release records in this phase can be counted. Assuming it is p times, the empty release time is n*p; for example: for 6 consecutive seconds, the total number of vehicles passing through the unit empty release record is 4, 3, 5, 2, 1, 4, 3, 5, 2, and 1; if 10 empty release records are counted, the empty release time is 6*10=60 seconds; if the total number of vehicles passing through the unit empty release record exceeds 5, then the continuous time is not empty release, and the empty release here can be understood as a relatively smooth traffic situation. In this embodiment, the national standard for phase is interpreted as the signal display status of one or more traffic flows that simultaneously obtain the right of way within a signal cycle. It can also be interpreted as the signal display status corresponding to a group of non-conflicting traffic flows that simultaneously obtain the right of way. We call it signal phase, or simply phase for short.

[0035] Step 2: Phase starts, save the start time tmG of this phase, create a mapping table qMapTV of the duration of this phase and the corresponding total number of vehicles leaving and a list of empty release data items in the evaluation system. In this embodiment, the start time tmG of this phase is used to calculate the duration of this phase, and the mapping table qMapTV is used to traverse and analyze and calculate the number of empty releases.

[0036] Step 3: Calculate the duration S of the release of this phase, count the total number of vehicles leaving all green light lanes during the release of this phase as N, generate a data group M storing S and N, and record it in the mapping table qMapTV; wherein, the duration S of the release of this phase is the difference between the current time and the start time tmG of this phase, S is a positive integer, and N is a natural number.

[0037] Step 4: The evaluation system compares the values ​​of S and n in real time. When S>n, it traverses all data groups in the mapping table qMapTV from the beginning to the end except the last data group.

[0038] Step 5: If the current data group is Mi, traverse each data group in the mapping table qMapTV one by one from the data group after the data group Mi; if the current data group is Mj, then when Sj-Si≥n and Nj-Ni<m, the number of empty discharge records p in this phase is executed once p=p+1; among them, i, j, p are all natural numbers, and the total empty discharge duration of this phase is the product of the number of empty discharge records p in this phase and the empty discharge time n of each time.

[0039] Step 6: Traverse all data groups in the mapping table qMapTV from the beginning to the end, until the current data group Mk is Mj, and delete the above data group from the mapping table qMapTV; wherein k is a natural number, and the above data group deleted from the mapping table qMapTV is all the data groups that have been traversed in the mapping table qMapTV. In this embodiment, steps 4, 5, and 6 are actually to calculate how many empty releases there are in the entire mapping table qMapTV that has been recorded in this phase. The traversal calculation method is mainly to compare each data group M in the mapping table qMapTV with all the data groups behind it one by one to analyze whether they meet the empty release conditions. When all the data groups in the mapping table qMapTV are analyzed, the empty release data is stored separately, and all the data groups that have been traversed are deleted.

[0040] Step 7: Create a new empty release data item and store it in the empty release data item list, where the empty release data item stores the phase time (Si) when the empty release of this phase starts and the phase time (Sj) when the empty release ends, as well as the corresponding total number of vehicles leaving Ni and Nj.

[0041] Step 8: The evaluation system monitors in real time whether the traffic control system has sent the next phase switching signal; wherein, when the evaluation system monitors in real time that the traffic control system has not sent the next phase switching signal, step 3 is executed.

[0042] Step 9: When the evaluation system monitors in real time that the traffic control system has sent the next phase switching signal, the current phase is ended, and the empty release index of the current phase is calculated and judged whether it meets the overall empty release, and the currently stored empty release data item list and the overall empty release data are fed back to the traffic control system; wherein, the total duration t of the current phase is calculated, and the total number of vehicles driving out during the release of the current phase q is calculated. When q<Q and q / t<v, it is determined that the current phase meets the overall empty release, and the value range of Q is 0≤Q≤10, Q is a natural number, and the value range of v is 0≤v≤0.5. The total duration t of the current phase is the difference between the current time of ending the current phase and the start time tmG of the current phase, and t is a natural number; when the current phase meets the overall empty release, the empty release duration of the current phase is directly the total duration t of the current phase. In this embodiment, the definition and calculation of overall vacancy is to record the vacancy time and vacancy percentage of each phase, and the vacancy percentage is vacancy time / phase duration, so as to make an overall evaluation of the dispatching efficiency within a period of time. The evaluation data can provide a basis for the traffic control system to optimize the timing of road intersection signals. Among them, when a phase record meets the overall vacancy condition, it is considered that the phase is vacant throughout the entire phase, and the vacancy time is the phase duration t, then the above-mentioned phase vacancy time will be replaced by this duration t; unlike the calculation of the phase vacancy record, the calculation of whether the phase is vacant as a whole must be calculated after the phase ends; in this way, we can record the vacancy time and vacancy percentage of each phase, and then make a more accurate overall evaluation of the dispatching efficiency of the road intersection within a period of time.

[0043] The present invention also provides a system for implementing the above-mentioned method for defining "empty release" to evaluate the dispatching efficiency of road intersections, comprising:

[0044] The phase basic data acquisition module is used to obtain the phase basic data of the traffic control system, including obtaining the duration S of the release of the current phase, obtaining the total number N of vehicles leaving all lanes with green lights during the release of the current phase; and is used to monitor in real time whether the traffic control system has sent the next phase switching signal;

[0045] The empty release index evaluation and calculation module is used to create a mapping table qMapTV and an empty release data item list of the duration of the current phase and the corresponding total number of vehicles leaving in the evaluation system; to generate a data group M storing S and N, and record it in the mapping table qMapTV; to compare the values ​​of S and n in real time, and when S>n, traverse all data groups in the mapping table qMapTV from the beginning to the end except the last data group; to traverse each data group in the mapping table qMapTV from the next data group of the data group Mi to the end; if the current data group is Mj, then when Sj-Si≥n and Nj-Ni<m, the empty release record number p of this phase is executed once p=p+1; to traverse all data groups in the mapping table qMapTV from the beginning to the end until the current data group Mk is Mj, and delete the above data group from the mapping table qMapTV; to end the current phase when it is monitored in real time that the traffic control system has sent the next phase switching signal, and calculate and judge whether the empty release index of this phase meets the overall empty release;

[0046] The statistics and feedback module is used to create a new empty release data item and store it in the empty release data item list; it is used to feed back the currently stored empty release data item list and the overall empty release data to the traffic control system.

[0047] In this embodiment, the empty lane assessment system maintains a real-time communication connection with the traffic command system. The phase basic data acquisition module of the empty lane assessment system acquires the basic data of each phase from the traffic command system in real time, including the duration S that the phase has been released, the total number N of vehicles leaving all green light lanes during the phase release process, and whether the traffic command system has sent the next phase switching signal; the empty lane index evaluation and calculation module evaluates and calculates the empty lane index of the phase and the overall empty lane index based on the basic data acquired by the phase basic data acquisition module, and finally the statistical module summarizes and feeds back to the traffic command system for real-time adjustment of the scheduling of road intersections.

[0048] As can be seen from the above, the beneficial effects of the present invention are as follows: the present invention provides a method and system for defining "empty release" to evaluate the dispatching efficiency of road intersections. By defining empty release to evaluate the traffic conditions of road intersections in real time, and calculating the dispatching efficiency of road intersections based on the empty release index, real-time feedback is then given to the traffic control system. The evaluation method is simple, the dispatching efficiency evaluation of road intersections is highly accurate, and real-time feedback can be achieved. After each phase is completed, the list of empty release data items and overall empty release data of the road intersection are fed back to the traffic control system once. The evaluation feedback speed is fast, which solves the problems of large errors, low effectiveness, and slow evaluation feedback in the algorithm for evaluating the dispatching scheme in the prior art. Moreover, in the evaluation over a longer period of time, such as multiple phases or multiple traffic light cycles, the overall empty release can also be used to evaluate the dispatching efficiency of the road intersection in each phase during this period of time, which is more accurate overall in the evaluation of the dispatching efficiency of long-term road intersections.

[0049] The specific implementation modes described above are preferred implementation modes of the present invention, and are not intended to limit the specific implementation scope of the present invention. The scope of the present invention includes but is not limited to the specific implementation modes, and all equivalent changes made according to the present invention are within the protection scope of the present invention.

Claims

1. A method for defining "empty release" to evaluate the efficiency of road intersection scheduling, characterized in that: It includes the following steps: Step 1: Define a no-vehicle release in the evaluation system. If the total number of vehicles leaving each sub-direction released in this phase does not exceed m within consecutive n seconds, it is recorded as a no-vehicle release once. Step 2: At the start of the phase, save the start time tmG of this phase, and create a mapping table qMapTV of the phase duration and the corresponding total number of vehicles leaving, and a list of no-vehicle release data items in the evaluation system. Step 3: Calculate the elapsed duration S of this phase that has been released, count the total number of vehicles leaving all green-light lanes during the release of this phase as N, generate a data group M storing S and N, and record it in the mapping table qMapTV. Step 4: The evaluation system compares the value of S with n in real time. When S > n, traverse all data groups in the mapping table qMapTV one by one from the beginning to the end except the last data group. Step 5: If the current data group is Mi, traverse each data group in the mapping table qMapTV one by one from the data group after Mi to the end; if the current data group is Mj, when Sj - Si ≥ n and Nj - Ni < m, the no-vehicle release record count p of this phase is incremented by 1, i.e., p = p + 1. Step 6: Traverse all data groups in the mapping table qMapTV one by one from the beginning to the end until the current data group Mk is Mj, and then delete the above data groups from the mapping table qMapTV. Step 7: Create a new no-vehicle release data item and store it in the list of no-vehicle release data items. Step 8: The evaluation system monitors in real time whether the traffic command system has sent a signal for the next phase switch. Step 9: When the evaluation system monitors in real time that the traffic command system has sent a signal for the next phase switch, end this phase, calculate and determine whether the no-vehicle release index of this phase meets the overall no-vehicle release, and feedback the currently stored list of no-vehicle release data items and the overall no-vehicle release data to the traffic command system.

2. The method for defining "empty release" to evaluate the efficiency of road intersection scheduling as claimed in claim 1, characterized in that: In the above Step 1, both n and m are natural numbers. The value range of n is 2 ≤ n ≤ 10, and the value range of m is 0 ≤ m ≤ 5.

3. The method for defining "empty release" to evaluate the efficiency of road intersection scheduling as claimed in claim 2, characterized in that: In the above Step 3, the elapsed duration S of this phase that has been released is the difference between the current time and the start time tmG of this phase. S is a positive integer, and N is a natural number.

4. The method for defining "empty release" to evaluate the efficiency of road intersection scheduling as claimed in claim 3, characterized in that: In the above Step 5, i, j, and p are all natural numbers. The total no-vehicle release duration of this phase is the product of the no-vehicle release record count p of this phase and the no-vehicle release time n each time.

5. The method for defining "empty release" to evaluate the dispatching efficiency of road intersections as claimed in claim 4, characterized in that: In the above Step 6, k is a natural number. The above data groups deleted from the mapping table qMapTV are all data groups that have been traversed in the mapping table qMapTV.

6. The method for defining "empty release" to evaluate the efficiency of road intersection scheduling as claimed in claim 5, characterized in that: In the above Step 7, the no-vehicle release data item stores the phase time (Si) at the start of the no-vehicle release of this phase and the phase time (Sj) at the end, as well as the corresponding total number of vehicles leaving Ni and Nj.

7. The method for defining "empty release" to evaluate the efficiency of road intersection scheduling as claimed in claim 6, characterized in that: In the above Step 8, when the evaluation system monitors in real time that the traffic command system has not sent a signal for the next phase switch, execute Step 3.

8. The method for defining "empty release" to evaluate the efficiency of road intersection scheduling as claimed in claim 7, characterized in that: In the above Step 9, calculate the total duration t of this phase, calculate the total number of vehicles leaving q during the release of this phase. When q < Q and q / t < v, it is determined that this phase meets the overall no-vehicle release. The value range of Q is 0 ≤ Q ≤ 10, Q is a natural number, and the value range of v is 0 ≤ v ≤ 0.

5.

9. The method for defining "empty release" to evaluate the efficiency of road intersection scheduling as claimed in claim 8, characterized in that: The total duration t of this phase is the difference between the current time when this phase ends and the start time tmG of this phase. t is a natural number. When this phase meets the overall idle release condition, the idle release duration of this phase is directly the total duration t of this phase.

10. A system for implementing the method for defining "empty release" to evaluate the dispatching efficiency of road intersections as described in any one of claims 1 to 9, characterized in that: Including: A phase basic data acquisition module, which is used to acquire the phase basic data of the traffic command system, including acquiring the duration S that has been released in this phase, and acquiring the total number N of vehicles leaving all green - state lanes during the release process of this phase; and is used to monitor in real - time whether the traffic command system has sent the next phase switching signal; An idle release index evaluation and calculation module, which is used to create a mapping table qMapTV of the phase duration and the corresponding total number of vehicles leaving and a list of idle release data items in the evaluation system; It is used to generate a data group M storing S and N and record it in the mapping table qMapTV; it is used to compare the values of S and n in real - time. When S > n, it traverses all data groups in the mapping table qMapTV except the last one from beginning to end; it is used to traverse each data group in the mapping table qMapTV from the next data group after the data group Mi to the end; if the current data group is Mj, when Sj - Si ≥ n and Nj - Ni < m, the idle release record count p of this phase executes p = p + 1 once; it is used to traverse all data groups in the mapping table qMapTV from beginning to end until the current data group Mk is Mj, and then delete the above - mentioned data group from the mapping table qMapTV; it is used to end this phase when it is monitored in real - time that the traffic command system has sent the next phase switching signal, and calculate and judge whether the idle release index of this phase meets the overall idle release; A statistics and feedback module, which is used to create a new idle release data item and store it in the list of idle release data items; and is used to feedback the currently stored list of idle release data items and the overall idle release data to the traffic command system.

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