Method for measuring and calculating green light effective utilization efficiency of signal control intersection

Abstract

According to the method for measuring and calculating the green light effective utilization efficiency of the signal control intersection, provided by the invention, the maximum idle time interval is set for each guide lane of the signal control intersection to be calculated, and the maximum idle time interval is used as the judgment threshold value; whether the vehicle passing time interval of each vehicle in the guide lane within the green light time is included in the green light effective utilization time is judged, and only the vehicle passing time interval larger than the maximum idle release time interval participates in calculation. Compared with an existing method for calculating by using an average value or a certain coverage condition value, the method has the advantages that the vehicle passing time interval of each vehicle is judged, and the accuracy of a statistical result is effectively improved.

Description

Technical Field

[0001] The present invention relates to the technical field of urban intelligent traffic control, and specifically to a method for calculating the utilization efficiency of the effective green time at signal-controlled intersections. Background Art

[0002] Most traffic signal control methods set timing plans in the traffic signal control system to reasonably control the intersection signal lights, reduce vehicle waiting time, alleviate urban traffic congestion, and improve the operation efficiency of urban traffic. The effective utilization efficiency of the green light is an important reference index for optimizing traffic signal timing plans and has important significance for intelligent traffic control. The common usage method is to carry out the calculation of traffic signal timing based on the effective utilization efficiency of the green light being a known value of the current situation or a theoretically set value. For example, CN115798226A discloses a signal control optimization method based on the green light utilization rate, aiming to minimize the waste of the green light. Through the limitation of constraint conditions, it ensures that the intersection saturation is increased within a reasonable range, reduces the ineffective waiting time of the corresponding other traffic flows, and reduces the intersection signal cycle time, thereby improving the operation efficiency of the intersection. CN111785038B discloses a single-point full-sensing signal timing method based on the utilization rate of the green light extension request area. According to the length and number of guiding lanes and the number, position, physical length, and speed of connected motor vehicles in the green light extension request area at the current moment, the utilization rate of the green light extension request area is calculated, and single-point full-sensing control is carried out to minimize the phenomena of green light waste and insufficient green light to the greatest extent. However, in the prior art, the acquisition of the effective utilization efficiency of the green light mainly obtains based on the theoretical research index value, and the technical research on how to accurately calculate the effective utilization efficiency of the green light at signal-controlled intersections is still blank. Summary of the Invention

[0003] To solve the problem that there is no method for calculating the effective utilization efficiency of the green light at signal-controlled intersections in the prior art, the present invention provides a method for calculating the effective utilization efficiency of the green light at signal-controlled intersections, which can accurately calculate the utilization efficiency of the green time effectively available for vehicle passage and provide accurate data support for other traffic control methods.

[0004] The technical solution of the present invention is as follows: A method for calculating the effective utilization efficiency of the green light at signal-controlled intersections, characterized in that it includes the following steps:

[0005] SS1: Determine the signal-controlled intersection to be calculated;

[0006] Collect the timing data of the traffic signal control system corresponding to the signal-controlled intersection in real time;

[0007] Determine the traffic flow detection device at the signal-controlled intersection, and based on the traffic flow detection device, collect the vehicle passing data corresponding to the intersection in real time;

[0008] SS2: Calculate the green light time corresponding to each phase of the signal-controlled intersection;

[0009] The green light time is the green light display time obtained by the phase of the signal-controlled intersection;

[0010] For any cycle i and any phase j, assuming the green light time is g i,j , then the calculation of the green light time is as follows:

[0011] g i,j = tend i,j - tbeg i,j ;

[0012] Among them, g i,j represents the green light time of the jth phase in the ith cycle, with the unit of s; tend i,j represents the end moment of the green light of the jth phase in the ith cycle; tbeg i,j represents the start moment of the green light of the jth phase in the ith cycle;

[0013] SS3: Set the maximum empty running time interval Tkong of the signal-controlled intersection i,j , and use it as the threshold for judging whether the vehicle passing time interval within the green light time is included in the effective utilization time of the green light;

[0014] The calculation method of the maximum empty running time interval Tkong of the signal-controlled intersection i,j is as follows:

[0015] For any cycle i and any phase j, assuming the maximum empty running time interval is Tkong i,j , then the calculation of the maximum empty running time interval is as follows:

[0016] Tkong i,j = L i,j ÷ Vlim i,j ;

[0017] Among them, Tkong i,j represents the maximum empty running time interval of the jth phase in the ith cycle, with the unit of s; L i,j represents the length of the guiding lane of the traffic flow approach road where the jth phase in the ith cycle obtains the right of way, with the unit of m; Vlim i,j represents the road speed limit value of the corresponding section of the traffic flow approach road where the jth phase in the ith cycle obtains the right of way, with the unit of m / s;

[0018] SS4: Determine the vehicle passing time interval Ttong that should be included in the green light empty running time i,j,m , and the specific method is as follows:

[0019] Assume that after the starting moment of the green light idle running time, the vehicle passing time interval is Ttong i,j,m ;

[0020] When Ttong i,j,m ≥Tkong i,j then, for the m-th vehicle after the starting moment of the green light idle running time in the j-th phase of the i-th cycle, the vehicle passing time interval Ttong i,j,m is counted as the green light idle running time Tnog i,j,m into the green light idle running time;

[0021] Otherwise, Ttong i,j,m is not counted into the green light idle running time;

[0022] SS5: Calculate the green light idle running time corresponding to each phase in the signal-controlled intersection;

[0023] The green light idle running time is the sum of all the vehicle green light idle running times after the starting moment of the green light idle running time;

[0024] The calculation method of the green light idle running time is as follows:

[0025] For any cycle i and any phase j, assume that the green light idle running time after the starting moment of the green light idle running time is Tnog i,j , then the green light idle running time after the starting moment of the green light idle running time is calculated as follows:

[0026]

[0027] where, Tnog i,j represents the green light idle running time after the starting moment of the green light idle running time in the j-th phase of the i-th cycle, with the unit of s; tend i,j represents the ending moment of the green light in the j-th phase of the i-th cycle; tkgb i,j represents the starting moment of the green light idle running time in the j-th phase of the i-th cycle; Tnog i,j,m represents the vehicle green light idle running time of the m-th vehicle after the starting moment of the green light idle running time in the j-th phase of the i-th cycle, with the unit of s; M represents the total number of vehicles passing after the starting moment of the green light idle running time in the j-th phase of the i-th cycle;

[0028] SS6: Specify the measurement time period;

[0029] SS7: Calculate the green light effective utilization efficiency corresponding to the signal-controlled intersection within the measurement time period;

[0030] The green light effective utilization efficiency of the signal-controlled intersection is the ratio of the green light effective utilization time to the green light time;

[0031] Assume that the effective utilization efficiency of the green light at a signal-controlled intersection is GTU. Then, the calculation of the effective utilization efficiency of the green light at a signal-controlled intersection is as follows:

[0032]

[0033] Among them, GTU represents the effective utilization efficiency of the green light at a signal-controlled intersection; g i,j represents the green light time of the j-th phase in the i-th cycle, with the unit of s; Tnog i,j represents the green light idle time after the start time of the green light idle time of the j-th phase in the i-th cycle, with the unit of s; I represents the total number of cycles within the measured time period of the signal-controlled intersection; Ni represents the total number of phases in the i-th cycle.

[0034] It is further characterized in that:

[0035] The start time tkgb of the green light idle time of the j-th phase in the i-th cycle i,j is calculated as follows:

[0036] The start time of the green light idle time is the end time of the minimum green light time;

[0037] For any cycle i and any phase j, assume that the start time of the green light idle time is tkgb i,j , then the start time of the green light idle time is calculated as follows:

[0038] tkgb i,j = tbeg i,j + Tmin i,j ;

[0039] Among them, tkgb i,j represents the start time of the green light idle time of the j-th phase in the i-th cycle; tbeg i,j represents the start time of the green light of the j-th phase in the i-th cycle; Tmin i,j represents the minimum green light time of the j-th phase in the i-th cycle;

[0040] The minimum green light time Tmin of the signal-controlled intersection i,j is the minimum holding time length of the green light signal at the signal-controlled intersection after comprehensively considering the traffic factors of the signal-controlled intersection; the traffic factors include: the traffic flow of the signal-controlled intersection, the length of the crosswalk, and the pedestrian step distance;

[0041] The green light idle time Tnog of the m-th vehicle after the start time of the green light idle time of the j-th phase in the i-th cycle i,j,m is calculated as follows:

[0042] Tnog i,j,mThe green - light idle time for the vehicle is the green - light time that is not effectively utilized by a single vehicle after the start time of the green - light idle time calculation;

[0043] For any cycle \(i\), any phase \(j\), and any vehicle \(m\), assume that the green - light idle time for the vehicle after the start time of the green - light idle time is \(T_{nog}\) i,j,m , then the green - light idle time for the vehicle after the start time of the green - light idle time is calculated as follows:

[0044]

[0045] where \(T_{nog}\) i,j,m represents the green - light idle time of the \(m\) - th vehicle after the start time of the green - light idle time for the \(j\) - th phase in the \(i\) - th cycle, with the unit of s; \(T_{tong}\) i,j,m represents the vehicle passing - time interval of the \(m\) - th vehicle after the start time of the green - light idle time for the \(j\) - th phase in the \(i\) - th cycle, with the unit of s; \(T_{kong}\) i,j represents the maximum idle - time interval of the \(j\) - th phase in the \(i\) - th cycle, with the unit of s;

[0046] The vehicle passing - time interval \(T_{tong}\) i,j,m is the time interval between two consecutive vehicles passing through the stop line of the signal - controlled intersection in chronological order after the start time of the green - light idle time. The calculation method is:

[0047] For any cycle \(i\), any phase \(j\), and any vehicle \(m\), assume that the vehicle passing - time interval after the start time of the green - light idle time is \(T_{tong}\) i,j,m , then the vehicle passing - time interval after the start time of the green - light idle time is calculated as follows:

[0048]

[0049] where \(T_{tong}\) i,j,m represents the vehicle passing - time interval of the \(m\) - th vehicle after the start time of the green - light idle time for the \(j\) - th phase in the \(i\) - th cycle, with the unit of s; \(t_{veh}\) i,j,1 represents the moment when the first vehicle passes through the stop line of the signal - controlled intersection after the start time of the green - light idle time for the \(j\) - th phase in the \(i\) - th cycle; \(t_{kgb}\) i,j represents the start time of the green - light idle time for the \(j\) - th phase in the \(i\) - th cycle; \(t_{veh}\) i,j,m represents the moment when the \(m\) - th vehicle passes through the stop line of the signal - controlled intersection after the start time of the green - light idle time for the \(j\) - th phase in the \(i\) - th cycle; \(t_{veh}\) i,j,m-1 represents the moment when the \((m - 1)\) - th vehicle passes through the stop line of the signal - controlled intersection after the start time of the green - light idle time for the \(j\) - th phase in the \(i\) - th cycle; \(M\) represents the total number of vehicles passing through after the start time of the green - light idle time for the \(j\) - th phase in the \(i\) - th cycle; \(t_{end}\) i,jDenote the end time of the green light for the j-th phase in the i-th cycle; tveh i,j,M Denote the time when the M-th vehicle passes the stop line of the signal-controlled intersection after the start time of the green-light free-running time for the j-th phase in the i-th cycle;

[0050] The time tveh when the vehicle passes the stop line of the signal-controlled intersection i,j,m is collected as follows:

[0051] Based on the time sequence, collect the time tveh when each vehicle passes the stop line of the signal-controlled intersection after the start time of the green-light free-running time in turn i,j,m .

[0052] A method for calculating the effective utilization efficiency of the green light at a signal-controlled intersection provided by this application sets a maximum free-running time interval Tkong for each guiding lane of the signal-controlled intersection to be calculated i,j , and use it as a judgment threshold to judge whether the vehicle passing time interval Ttong of each vehicle in the guiding lane during the green-light time i,j,m should be included in the effective utilization time of the green light. Only Ttong i,j greater than Tkong i,j,m is involved in the calculation. Compared with the existing methods that use the average value or a certain coverage condition value for calculation, this method judges the vehicle passing time interval Ttong of each vehicle i,j,m , effectively improving the accuracy of the statistical results; this method can accurately calculate the effective utilization efficiency of the green light at the signal-controlled intersection, and the calculation results are targeted for the signal-controlled intersection. At the same time, all the data in the whole process can be collected based on the traffic signal control system and traffic flow detection equipment in the intersection, with the advantages of good operability, real-time performance and effectiveness. Description of the Drawings

[0053] Figure 1 is a schematic flow chart of a method for calculating the effective utilization efficiency of the green light at a signal-controlled intersection;

[0054] Figure 2 is a schematic diagram of some index data during the green-light time;

[0055] Figure 3 is a schematic diagram of an example intersection. Detailed Embodiments

[0056] This application provides a method for calculating the effective utilization efficiency of the green light at a signal-controlled intersection. This method can be applied to any traffic signal-controlled intersection to calculate the quantification of the effective utilization efficiency of the traffic signal control scheme implemented in the intersection in real time. Figure 3Shows a schematic diagram of a traffic signal - controlled intersection provided by an exemplary embodiment of the present application. It is an actual traffic signal - controlled intersection in XX City. In this embodiment, the timing plan data is automatically extracted through the traffic signal control system of the example intersection, and the vehicle passing data is automatically extracted through traffic flow detection devices, and the green - light effective utilization efficiency of the traffic signal control plan for the intersection in this embodiment is calculated.

[0057] Figure 3 Among them, the shape of the traffic signal - controlled intersection is a "+" intersection, connecting the roads in the east, south, west, and north directions. The roads in each direction are composed of motor vehicle lanes, non - motor vehicle lanes, and sidewalks. The guiding lanes of the motor vehicle approach lanes in each direction of the road can be further divided into left - turn lanes, straight - through lanes, and right - turn lanes. The traffic signals at the example intersection do not implement bus - priority control. Since all right - turn lanes at the intersection are dedicated independent lanes and there are no traffic signal lights corresponding to the right - turn directions to control the passing of right - turn motor vehicles, and non - motor vehicles in all directions pass according to the indications of the corresponding motor - vehicle direction - indicating signal lights, the right - turn lanes and non - motor vehicle lanes are not drawn in the figure.

[0058] The present application provides a method for calculating the green - light effective utilization efficiency of a signal - controlled intersection. Applying this method to the Figure 3 traffic signal - controlled intersection shown, starting from the step of collecting data, as Figure 1 shown, it specifically includes the following content.

[0059] S1: Calculate the green - light time of the signal - controlled intersection.

[0060] The green - light time is the green - light display time obtained by the phase of the signal - controlled intersection; for any cycle i and any phase j, assuming the green - light time is g i,j , then the calculation of the green - light time is as follows:

[0061] g i,j = tend i,j - tbeg i,j ;

[0062] Among them, g i,j represents the green - light time of the j - th phase in the i - th cycle, with the unit of s; tend i,j represents the end moment of the green - light of the j - th phase in the i - th cycle; tbeg i,j represents the start moment of the green - light of the j - th phase in the i - th cycle; the specific values of tend i,j and tbeg i,j can be automatically extracted from the traffic signal control system.

[0063] In the embodiment of the present application, Figure 3One signal cycle of the traffic signal timing plan for a sample traffic signal - controlled intersection in the morning of a certain day is used as the cycle for calculating the effective utilization efficiency of the green light. The starting time of this cycle is 7:21:12 Beijing time, and the ending time is 7:23:12 Beijing time.

[0064] In this embodiment, the selected traffic signal control cycle consists of four phases. The green - light interval time between two consecutive different phases is 6 s. For the starting time of the phase green light, the ending time of the phase green light, the phase green - light time, and the total cycle green - light time corresponding to the four phases, refer to Table 1.

[0065] Table 1 Phase green - light embodiment

[0066]

[0067] According to Table 1, the traffic signal cycle serial number of the embodiment is assigned as 1, that is, i = 1. The value range of the phase serial number of the traffic signal cycle in the embodiment is 1, 2, 3, 4, that is, j = 1, 2, 3, 4.

[0068] The green - light display times obtained for the phases of the traffic signal - controlled intersection in the embodiment are as follows:

[0069] g 1,1 =tend 1,1 -tbeg 1,1 =(7:21:36)-(07:21:12)=24(s);

[0070] g 1,2 =tend 1,2 -tbeg 1,2 =(7:22:06)-(07:21:42)=24(s);

[0071] g 1,3 =tend 1,3 -tbeg 1,3 =(7:22:36)-(07:22:12)=24(s);

[0072] g 1,4 =tend 1,4 -tbeg 1,4 =(7:23:06)-(07:22:42)=24(s).

[0073] S2: Determine the minimum green - light time of the signal - controlled intersection;

[0074] The minimum green - light time is the shortest time that the green - light signal should maintain, considering factors such as the traffic flow at the signal - controlled intersection, the length of the crosswalk, and the pedestrian step distance. For any cycle i and any phase j, assume its minimum green - light time is Tmini,j , in seconds. Usually, when configuring a traffic signal control system for each intersection, the timing plan will include the minimum green time. The minimum green time takes into account both the shortest time for vehicles to safely pass through the intersection and the shortest time for pedestrians to safely pass through the intersection. The specific algorithm belongs to the prior art. This method can be directly read from the timing plan of the traffic signal control system.

[0075] In this embodiment, the timing plan is automatically extracted from the traffic signal control system. According to the actually operating timing plan, the minimum green times of phase 1, phase 2, phase 3, and phase 4 in cycle 1 have been set respectively, as shown in Table 2 for details.

[0076] Table 2 Examples of minimum green times

[0077]

[0078] S3: Calculate the maximum idle time interval Tkong of the signal-controlled intersection i,j .

[0079] In this method, the maximum idle time interval Tkong is set i,j as the judgment threshold for whether the vehicle passing time interval within the green time is included in the effective utilization time of the green light; for any cycle i and any phase j, assuming the maximum idle time interval is Tkong i,j , then the maximum idle time interval is calculated as follows:

[0080] Tkong i,j = L i,j ÷Vlim i,j ;

[0081] where, Tkong i,j represents the maximum idle time interval of the jth phase in the ith cycle, in seconds; L i,j represents the length of the guiding lane of the traffic flow approach lane that obtains the right of way in the jth phase of the ith cycle, in meters; Vlim i,j represents the road speed limit value of the corresponding section of the traffic flow approach lane that obtains the right of way in the jth phase of the ith cycle, in m / s.

[0082] Under the condition of the effective utilization efficiency of the green light under ideal conditions, when the green light duration of the intersection guiding lane meets the minimum green time of Tmin i,j , the interval between vehicles passing through the stop line of the signal-controlled intersection should be less than the maximum idle time interval Tkong i,j , that is, under the ideal effective utilization efficiency of the green light, the distance between two adjacent vehicles in the same phase should be less than the length L of the guiding lane of the traffic flow approach lane that obtains the right of way i,j; and once the distance between any two adjacent vehicles is greater than L i,j , it means that the passage of the following vehicle can be postponed to the next green light phase, that is, there is an idle time in the green light phase. Therefore, in this application, the Tkong i,j value is calculated based on the guiding lane length L i,j of the traffic flow approach lane that obtains the right of way and the road speed limit value Vlim i,j of the corresponding section of the traffic flow approach lane, ensuring that the maximum idle time interval Tkong i,j is targeted, and thus ensuring the accuracy of the calculation result. In practical applications, if the lengths and road speed limit values of multiple guiding lanes corresponding to the traffic flow approach that obtains the right of way in the same phase at the same intersection are the same, the maximum idle time intervals and green light effective utilization rates corresponding to these guiding lanes can be calculated uniformly as a whole. If there are different values for the lengths or road speed limit values between the guiding lanes corresponding to the traffic flow approach that obtains the right of way in the same phase of the intersection, the maximum idle time intervals and green light effective utilization rates corresponding to these guiding lanes with different values are calculated separately.

[0083] In this embodiment, according to the actual operating traffic signal control timing plan and the example intersection guiding lane line length values, the maximum idle time interval values of Phase 1, Phase 2, Phase 3, and Phase 4 in Cycle 1 are shown in Table 3.

[0084] Table 3 Example of Maximum Idle Time Interval

[0085]

[0086] S4: Calculate the starting moment of the green light idle time of the signal control intersection.

[0087] During the green light duration of each phase, the length of the minimum green light time should be guaranteed at a minimum, and the calculation of the green light effective utilization rate is for the green light duration outside the minimum green light time within the phase. Therefore, to ensure the accuracy of the calculation result, this application sets the starting moment of the green light idle time to mark the green light duration outside the minimum green light time in each phase.

[0088] The starting moment of the green light idle time is the starting moment for statistically calculating the green light idle time of vehicles, that is, the end moment of the minimum green light time; for any cycle i and any phase j, assuming the starting moment of the green light idle time is tkgb i,j , then the calculation of the starting moment of the green light idle time is as follows:

[0089] tkgb i,j = tbeg i,j + Tmin i,j ;

[0090] Among them, tkgb i,j represents the starting moment of the green light idle running time of the j-th phase in the i-th cycle; tbeg i,j represents the starting moment of the green light of the j-th phase in the i-th cycle; Tmin i,j represents the minimum green light time of the j-th phase in the i-th cycle.

[0091] In this embodiment, according to the actual timing plan, the starting moments of the green light idle running times of phases 1, 2, 3, and 4 in cycle 1 are shown in Table 4.

[0092] Table 4 Starting Moments of Green Light Idle Running Times in the Embodiment

[0093]

[0094] S5: Based on the traffic flow detection device, in chronological order, successively collect the moments when each vehicle passes the stop line of the signal-controlled intersection after the starting moment of the green light idle running time; for any cycle i, any phase j, and any vehicle m, assume that the moment when the vehicle passes the stop line of the signal-controlled intersection after the starting moment of the green light idle running time is tveh i,j,m .

[0095] In this embodiment, according to phases 1, 2, 3, and 4 of cycle 1, from the starting moment of the green light idle running time of each phase until the end time of the green light, record one by one the moments when the vehicles that obtain the right of way pass the stop line of the signal-controlled intersection, as shown in Table 5.

[0096] Table 5 Moments When Vehicles Pass the Stop Line of the Signal-Controlled Intersection in the Embodiment

[0097]

[0098] S6: Calculate the vehicle passing time interval Ttong after the starting moment of the green light idle running time of the signal-controlled intersection i,j,m .

[0099] The vehicle passing time interval is the time interval between the moments when two consecutive vehicles pass the stop line of the signal-controlled intersection in chronological order after the starting moment tkgb of the green light idle running time. Based on the traffic flow detection device, by completing the collection of the time points when vehicles pass the stop line of the signal-controlled intersection and then calculating the difference, the vehicle passing time interval can be obtained. k,j For the first vehicle, calculate the time difference between the time when the first vehicle passes the stop line of the signal-controlled intersection and the starting moment tkgb

[0100] ; for the last vehicle, calculate the time difference between the time when the last vehicle passes the stop line of the signal-controlled intersection and the end moment tend of the green light of the j-th phase in the i-th cycle i,j ; i,jThe time difference; for the passing time intervals corresponding to the vehicles between the first and the last in the same green light phase, the time difference between the moments when adjacent vehicles pass the stop line of the signal-controlled intersection is statistically counted; this method can ensure that the data of all vehicles passing within the same phase can be accurately counted. Whether the vehicle data within this phase is large or small, this method sets the starting moment tkgb of the green light idle running time i,j , which is used in conjunction with the green light end moment tend i,j to ensure that all vehicle passing situations within this phase can be covered, ensuring that this method is more practical. Specifically, for the schematic diagrams of each time period in the green light time g i,j , refer to Appendix Figure 2 .

[0101] For any cycle i, any phase j, and any vehicle m, assuming that the passing time interval of the vehicle after the starting moment of the green light idle running time is Ttong i,j,m , then the passing time interval of the vehicle after the starting moment of the green light idle running time is calculated as follows:

[0102]

[0103] Where, Ttong i,j,m represents the passing time interval of the m-th vehicle after the starting moment of the green light idle running time in the j-th phase of the i-th cycle, with the unit of s; tveh i,j,1 represents the moment when the first vehicle passes the stop line of the signal-controlled intersection after the starting moment of the green light idle running time in the j-th phase of the i-th cycle; tkgb i,j represents the starting moment of the green light idle running time in the j-th phase of the i-th cycle; tveh i,j,m represents the moment when the m-th vehicle passes the stop line of the signal-controlled intersection after the starting moment of the green light idle running time in the j-th phase of the i-th cycle; tveh i,j,m-1 represents the moment when the (m - 1)-th vehicle passes the stop line of the signal-controlled intersection after the starting moment of the green light idle running time in the j-th phase of the i-th cycle; M represents the total number of vehicles passing after the starting moment of the green light idle running time in the j-th phase of the i-th cycle; tend i,j represents the green light end moment in the j-th phase of the i-th cycle; tveh i,j,M represents the moment when the M-th vehicle passes the stop line of the signal-controlled intersection after the starting moment of the green light idle running time in the j-th phase of the i-th cycle.

[0104] In this embodiment, the passing time intervals of the vehicles after the starting moment of the green light idle running time in the exemplary signal-controlled intersection are shown in Table 6.

[0105] Table 6 Passing Time Interval Embodiment

[0106]

[0107] S7: Calculate the vehicle green - light idle time after the starting moment of the green - light idle time at the signal - controlled intersection.

[0108] The vehicle green - light idle time is the green - light time that is not effectively utilized by a single vehicle after the starting moment of the green - light idle time. Based on the judgment threshold Tkong i,j and Ttong corresponding to each vehicle i,j,m Judge. Ttong i,j,m Greater than or equal to Tkong i,j Indicates that the distance between the m - th vehicle and the (m - 1)-th vehicle is greater than or equal to the guiding - lane length L of the traffic - flow approach lane that obtains the right of way i,j That is, in the ideal case of the effective utilization rate of the green - light, the m - th vehicle should be released to pass in the next green - light phase. Therefore, the vehicle passing - time interval Ttong i,j,m Corresponding to the m - th vehicle in this method should be counted into the vehicle green - light idle time.

[0109] For any cycle i, any phase j, and any vehicle m, assuming that the vehicle green - light idle time after the starting moment of the green - light idle time is Tnog i,j,m Then the vehicle green - light idle time after the starting moment of the green - light idle time is calculated as follows:

[0110]

[0111] Among them, Tnog i,j,m Represents the green - light idle time of the m - th vehicle after the starting moment of the green - light idle time in the j - th phase of the i - th cycle, with the unit of s; Ttong i,j,m Represents the vehicle passing - time interval of the m - th vehicle after the starting moment of the green - light idle time in the j - th phase of the i - th cycle, with the unit of s; Tkong i,j Represents the maximum idle - time interval in the j - th phase of the i - th cycle, with the unit of s.

[0112] The vehicle green - light idle time after the starting moment of the green - light idle time at the exemplary signal - controlled intersection is shown in Table 7.

[0113] Table 7 Examples of the vehicle green - light idle time after the starting moment of the green - light idle time

[0114]

[0115] S8: Calculate the green - light idle time after the starting moment of the green - light idle time at the signal - controlled intersection.

[0116] During the green light time of each phase, count the vehicles passing through the stop line of the signal-controlled intersection after the minimum green light time. If no vehicle passes through after the minimum green light time, the green light time of the same phase outside the minimum green light time is regarded as the green light idle running time. If there are vehicles passing through, that is, m is not 0, then sum the values according to Tnog corresponding to each vehicle. i,j,m The sum value is calculated.

[0117] The green light idle running time is the sum of the green light idle running times of all vehicles after the starting moment of the green light idle running time; for any cycle i and any phase j, assuming the green light idle running time after the starting moment of the green light idle running time is Tnog i,j , then the green light idle running time after the starting moment of the green light idle running time is calculated as follows:

[0118]

[0119] Among them, Tnog i,j represents the green light idle running time after the starting moment of the green light idle running time of the j-th phase in the i-th cycle, with the unit of s; tend i,j represents the end moment of the green light of the j-th phase in the i-th cycle; tkgb i,j represents the starting moment of the green light idle running time of the j-th phase in the i-th cycle; Tnog i,j,m represents the green light idle running time of the m-th vehicle after the starting moment of the green light idle running time of the j-th phase in the i-th cycle, with the unit of s; M represents the total number of vehicles passing through after the starting moment of the green light idle running time of the j-th phase in the i-th cycle.

[0120] In this embodiment, as can be seen from Table 6, the passing moments of the vehicles corresponding to Phase 1 of Cycle 1 of the example signal-controlled intersection through the stop line of the signal-controlled intersection are all within the minimum green light time of the phase. Therefore, the green light idle running time of the vehicles in this phase is Tnog 1,1 = tend 1,1 - tkgb 1,1 =(7:21:36)-(07:21:30)=6s.

[0121] In this embodiment, the green light idle running times of the vehicles after the starting moment of the green light idle running time of the example signal-controlled intersection are shown in Table 8.

[0122] Table 7 Vehicle Green Light Idle Running Time Embodiment

[0123]

[0124] S9: Calculate the effective utilization efficiency of the green light of the signal-controlled intersection.

[0125] The effective utilization efficiency of the green light at a signal-controlled intersection is the ratio of the effective green light utilization time to the green light time. Assuming the effective utilization efficiency of the green light at a signal-controlled intersection is GTU, the calculation method for the effective utilization efficiency of the green light at a signal-controlled intersection within the measurement period is as follows:

[0126]

[0127] where GTU represents the effective utilization efficiency of the green light at a signal-controlled intersection; g i,j represents the green light time of the jth phase in the ith cycle, with the unit of s; Tnog i,j represents the green light idle time after the starting moment of the green light idle time of the jth phase in the ith cycle, with the unit of s; I represents the total number of cycles within the measurement period of the signal-controlled intersection; Ni represents the total number of phases in the ith cycle.

[0128] In this embodiment, the effective utilization efficiency of the green light at the exemplary signal-controlled intersection is as follows:

[0129]

[0130] After using the technical solution of the present invention, based on the actual traffic signal control system timing plan data and the vehicle passing data of traffic flow detection equipment, the effective utilization efficiency of the green light at the signal-controlled intersection is obtained through processing and calculation. The result is objective and real, and can reflect the real situation of the effective utilization efficiency of the green light at the signal-controlled intersection, with good operability and effectiveness. The effective green light utilization rate statistically based on this method can provide data support for the traffic management department to carry out traffic signal control benefit evaluation and traffic signal timing plan optimization.

Claims

1. A method for calculating the effective utilization efficiency of green lights at signal-controlled intersections, characterized in that: It includes the following steps: SS1: Determine the signal-controlled intersection to be calculated; Real-time collection of the timing data of the traffic signal control system corresponding to the signal-controlled intersection; Determine the traffic flow detection equipment of the signal-controlled intersection, and collect vehicle traffic data corresponding to the intersection in real time based on the traffic flow detection equipment; SS2: Calculate the green light time corresponding to each phase of the signal-controlled intersection; The green light time is the green light display time obtained by the phase of the signal-controlled intersection; For any cycle i and any phase j, assuming the green light time is g i,j , the green light time is calculated as follows: g i,j =tend i,j -tbeg i,j ; Among them, g i,j Indicates the green light time of the jth phase in the i-th cycle, in seconds; tend i,j Indicates the end time of the green light in the jth phase of the i-th cycle; tbeg i,j Indicates the green light start time of the jth phase of the i-th cycle; SS3: Set the maximum time interval Tkong for signal controlled intersections i,j , which is used as the threshold for judging whether the time interval of vehicles passing during the green light time is included in the effective utilization time of the green light; Maximum vacant time interval Tkong at signal controlled intersection i,j The calculation method is: For any cycle i and any phase j, assuming the maximum idle time interval is Tkong i,j , the maximum idle time interval is calculated as follows: Tkong i,j =L i,j ÷Vlim i,j ; Among them, Tkong i,j Indicates the maximum idle time interval of the jth phase in the i-th cycle, in seconds; L i,j Vlim represents the length of the guide lane of the traffic flow entrance that obtains the right of way in the jth phase of the i-th cycle, in meters; i,j It indicates the road speed limit of the corresponding section of the entrance road of the traffic flow that obtains the right of way in the jth phase of the i-th cycle, in m / s; SS4: Determine the vehicle time interval Ttong that should be included in the green light free time i,j,m , the specific method is as follows: Assume that the time interval between vehicles passing after the green light is vacant is Ttong i,j,m ; When Ttong i,j,m ≥Tkong i,j When the green light vacant time of the jth phase in the i-th cycle is calculated, the vehicle passing time interval Ttong of the mth vehicle after the starting time of the green light vacant time of the jth phase in the i-th cycle is i,j,m As the vehicle green light idle time Tnog i,j,m It is counted as green light free time; Otherwise, Ttong i,j,m It is not counted in the green light idle time; SS5: Calculate the green light vacancy time corresponding to each phase in the signal-controlled intersection; The green light vacant time is the sum of the green light vacant time of all vehicles after the green light vacant time starts. The green light idle time calculation method is: For any cycle i and any phase j, assume that the green light idle time after the green light idle time starts is Tnog i,j , then the green light vacant time after the green light vacant time starting time is calculated as follows: Among them, Tnog i,j Indicates the green light idle time of the jth phase of the i-th cycle after the start time of the green light idle time, in seconds; tend i,j Indicates the green light end time of the jth phase of the i-th cycle; tkgb i,j Indicates the starting time of the green light no-load time of the jth phase of the i-th cycle; Tnog i,j,m It represents the vehicle green light vacancy time of the mth vehicle after the start time of the green light vacancy time of the jth phase of the i-th cycle, in seconds; M represents the total number of vehicles that have passed after the start time of the green light vacancy time of the jth phase of the i-th cycle; SS6: Specify the measurement period; SS7: Calculate the effective utilization efficiency of the green light corresponding to the signal-controlled intersection within the measurement time period; The green light effective utilization efficiency of the signal-controlled intersection is the ratio of the green light effective utilization time to the green light time; Assuming that the effective utilization efficiency of the green light at a signal-controlled intersection is GTU, the effective utilization efficiency of the green light at a signal-controlled intersection is calculated as follows: Among them, GTU represents the effective utilization efficiency of the green light at the signal-controlled intersection; g i,j Indicates the green light time of the jth phase in the i-th cycle, in seconds; Tnog i,j It represents the green light vacancy time after the start time of the green light vacancy time of the jth phase of the i-th cycle, in seconds; I represents the total number of cycles in the measurement time period of the signal-controlled intersection; Ni represents the total number of phases in the i-th cycle.

2. According to the method for calculating the effective utilization efficiency of green lights at signalized intersections as described in claim 1, it is characterized by: The starting time of the green light idle time of the jth phase in the i-th cycle tkgb i,j The calculation method is: The starting time of the green light vacant time is the end time of the minimum green light time; For any cycle i and any phase j, assuming that the green light idle time starts at tkgb i,j , then the starting time of the green light vacant time is calculated as follows: <h2 style=";text-align:left;direction:ltr">tkgb<h2 style=";text-align:left;direction:ltr"> i,j <h2 style=";text-align:left;direction:ltr"> =tbeg<h2 style=";text-align:left;direction:ltr"> i,j <h2 style=";text-align:left;direction:ltr"> +Tmin<h2 style=";text-align:left;direction:ltr"> i,j <h2 style=";text-align:left;direction:ltr"> ; Among them, tkgb i,j Indicates the starting time of the green light idle time of the jth phase of the i-th cycle; tbeg i,j Indicates the green light start time of the jth phase of the i-th cycle; Tmin i,j Indicates the minimum green light time of the jth phase in the i-th cycle.

3. According to the method for calculating the green light utilization efficiency of a signalized intersection as described in claim 2, it is characterized by: The minimum green light time Tmin of the signal-controlled intersection i,j The minimum length of time that the green light signal at a signalized intersection is maintained after comprehensively considering the traffic factors at the signalized intersection; the traffic factors include: traffic flow at the signalized intersection, length of the crosswalk and pedestrian stride.

4. According to the method for calculating the effective utilization efficiency of green lights at signalized intersections as described in claim 1, it is characterized by: The green light vacant time Tnog of the mth vehicle after the start time of the green light vacant time of the jth phase of the i-th cycle i,j,m The calculation method is: Tnog i,j,m The green light vacant time of the vehicle is the green light time that is not effectively used by a single vehicle after the green light vacant time starts to be calculated; For any cycle i, any phase j, and any vehicle m, assume that the vehicle green light idling time after the green light idling time starts is Tnog i,j,m , then the green light idling time of vehicles after the green light idling time starts is calculated as follows: Among them, Tnog i,j,m Indicates the green light vacancy time of the mth vehicle after the start time of the green light vacancy time of the jth phase of the i-th cycle, in seconds; Ttong i,j,m It indicates the time interval of the mth vehicle after the start of the green light vacant time of the jth phase of the i-th cycle, in seconds; Tkong i,j It indicates the maximum idle time interval of the jth phase in the i-th cycle, in seconds.

5. According to the method for calculating the green light utilization efficiency of a signal-controlled intersection as described in claim 1, it is characterized by: The vehicle passage time interval Ttong i,j,m It is the time interval between two vehicles passing through the stop line of the signalized intersection in chronological order after the green light is released. The calculation method is: For any cycle i, any phase j, and any vehicle m, assume that the vehicle time interval after the green light vacancy time starts is Ttong i,j,m , then the vehicle passing time interval after the green light vacant time starts is calculated as follows: Among them, Ttong i,j,m It indicates the time interval of the mth vehicle after the start of the green light vacant time of the jth phase of the i-th cycle, in seconds; tveh i,j,1 It indicates the time when the first vehicle passes the stop line of the signalized intersection after the start time of the green light vacant time of the jth phase of the i-th cycle; tkgb i,j Indicates the starting time of the green light idle time of the jth phase of the i-th cycle; tveh i,j,m It indicates the time when the mth vehicle passes the stop line of the signal-controlled intersection after the start time of the green light vacant time of the jth phase of the i-th cycle; tveh i,j,m-1 represents the time when the m-1th vehicle passes through the stop line of the signal-controlled intersection after the start time of the green light vacancy time of the jth phase of the i-th cycle; M represents the total number of vehicles passing after the start time of the green light vacancy time of the jth phase of the i-th cycle; tend i,j Indicates the end time of the green light in the jth phase of the i-th cycle; tveh i,j,M It indicates the time when the Mth vehicle passes through the stop line of the signalized intersection after the start time of the green light vacant time of the jth phase in the i-th cycle.

6. The method for calculating the green light utilization efficiency at a signalized intersection according to claim 1, characterized in that: The time tveh when the vehicle passes the stop line of the signal-controlled intersection i,j,m The collection method is: Based on the time sequence, the time tveh of each vehicle passing through the stop line of the signal-controlled intersection after the green light vacant time starts is collected in sequence i,j,m .

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