CN103280113A - Self-adaptive intersection signal control method - Google Patents

Abstract

The invention belongs to the field of urban traffic control, and provides a self-adaptive intersection signal control method. By installing vehicle monitors to detect the number of vehicles, the lengths of vehicle queues are acquired, and a signal control strategy for the next cycle is determined according to the lengths of vehicle queues at an intersection in the previous cycle. The method utilizes the vehicle detectors already arranged in a city to acquire traffic flow data and calculate the length of the queue of each lane, and the signal timing scheme of the next cycle is dynamically adjusted according to the different proportions of queue lengths. Taking a cycle as a unit, a timing scheme is calculated, the load of calculation is low, and moreover, the method also can achieve the purpose that intersection signals can be self-adaptively controlled according to the density of traffic flow. In addition, the algorithm of the method is simple, and the method has low requirement on hardware and construction quantity, and therefore is convenient to popularize.

Description

A kind of adaptive intersection signal control method

Technical field

The invention belongs to the urban traffic control field, be specifically related to a kind of adaptive intersection signal control method.

Background technology

Traffic signals control is control object with crossing microcosmic wagon flow, be that yardstick distributes vehicle at the right of way of crossing with phase place and time, separate the wagon flow of conflicting from the time, traffic flow is reasonably guided and dispatches, reach the minimizing traffic hazard, improve the purpose of traffic safety and conevying efficiency.

At present, intersection signal control method both domestic and external mainly contains timing controlled, induction control and adaptive control three classes, and timing controlled is suitable for the crossing that the volume of traffic is big and traffic is evenly distributed; It is less than normal that induction control is suitable for the volume of traffic, changes inhomogeneous crossing, but the volume of traffic is when big, can't adjust and optimize signal condition with the alleviation traffic congestion according to transport need; Adaptive control is the traffic data of sending here according to detecting device, produce the best timing scheme under certain performance index in real time, automatically regulate signal timing dial parameters such as split, Cycle Length and the green time difference, the traffic flow of signal timing dial and variation is adapted, at present, SCOOT and SCATS are the city traffic signal lamp self-adaptation control methods of two kinds of main flows.The SCATS system adjusts the signal controlling parameter in real time according to the traffic flow situation of change, but the possibility limited amount, carry out each scheme time long (scheme of variation in tens minutes), do not possess feedback function, and before checkout equipment is placed on stop line, can't detect vehicle queue length; The SCOOT system availability is strong, can adopt the continuity inching to timing parameter, but its relevant control model all comes out by mathematical model simulation, and mathematical model is more complicated, and required simulation time is just more long, can produce contradiction between reliability and the real-time.In addition, SCOOT and SCATS system all need to gather mass data, the construction cost height.

The crossing vehicle queue length is an important indicator that characterizes traffic behavior, and present optimum live signal control is mainly found the solution based on each import track queue length of crossing.But, calculate comparatively complexity of queue length, rely on a plurality of detecting devices usually or utilize vedio data, the calculated amount that realtime graphic is handled is very big, expensive, and is subject to weather effect, and the reliability of system is relatively poor.Present most of city has been laid equipment such as inductive coil and has been obtained the volume of traffic, the vehicle holding time, the road occupancy, Real-time Traffic Information such as the degree of crowding and queue length, but the transport need of crossing all directions might not balance, the queue length in each import track also not necessarily equates, particularly under the bigger situation of the volume of traffic, when detecting device is taken by certain in the formation vehicle commander time, be unable to estimate information such as the vehicle number of real-time arrival and queue length, thereby cause the vehicle queue length computational accuracy not high, the signal time distributing conception out of true.If in every track a plurality of detecting devices are installed, not only cause many places to damage to original road surface, and quantities is big, inconvenience is installed, the feasibility of engineering and the operability of enforcement are lower.

Summary of the invention

Shortcomings and deficiencies at prior art exists the objective of the invention is to a kind of adaptive intersection signal control method, and this method realizes intersection signal control by the crossing vehicle queue length in last cycle.

A kind of adaptive intersection signal control method, this method is carried out according to following steps:

Step 1,1 wagon detector is installed in each track in the crossing, and the distance of vehicle sensors and stop line is designated as L, and each wagon detector is used for gathering the red light in each phase place n cycle and opens the bright moment

The green light in n cycle opens the bright moment

The red light in n+1 cycle opens the bright moment

Holding time t when each vehicle passes through wagon detector _o, wagon detector free time t at interval _fReach the vehicle number n by detecting device;

Described phase place comprises the phase place of turning left at the craspedodrome phase place at craspedodrome formation place and the formation place of turning left;

One-period is carved into green light when bright for opening from red light and extinguishes constantly note G _MinBe minimum green time, note g _LayFor the unit green light prolongs or the shortening time, note G _MainMaximum total green time for major trunk roads;

Step 2, when the one-period effective green time finishes, wagon detector will detect data transmission and give the back-end data disposal system, analyze the variation of traffic behavior in this cycle, find out the transition moment T of wagon detector eigenstate _A, T _BAnd T _C

T _ABe that red light opens bright back vehicle v ₁Beginning takies the transition between states moment of wagon detector, T for a long time _AConstantly, wagon detector is by vehicle v ₁Take for a long time, constantly T _ACan be used to determine whether this phase place track exists long vehicle formation;

T _BBe that green light opens bright back vehicle v ₁Sail out of the transition of wagon detector constantly, green light open bright after, T _BConstantly, the vehicle before the stop line sails out of the crossing with saturation volume rate successively, but is 0 by the vehicle number of detecting device, at T _BAfterwards, by wagon detector, reduce by the holding time of wagon detector and interval time with the current flow rate of maximum for vehicle;

T _CBe last car v in the vehicle queue formation ₂By the transition between states moment of wagon detector, determine last car of formation v ₂Foundation be: in the queue queue continuously during the vehicle passing detection device interval time less, when a car and its Following Car pass through detecting device interval greater than threshold value A, illustrate in not Queue here of the Following Car formation;

The value that obtains threshold value A according to present traffic study data statistics result is 3s;

Step 3, adopt from

The time be carved into T _APass through the vehicle number n of detecting device in time period constantly _LCalculate the vehicle density k under the saturated conditions _j, k then _j=n _L/ L; Employing from

The time be carved into T _BTime period and stop line calculate the dissipation speed v of vehicle queue formation to the distance L between wagon detector constantly, then

And then pass through T _BAnd T _CPass through the vehicle number n of detecting device in time period _jCalculate the maximum queue length Q in this cycle;

(1) if there is not T _AConstantly, Q＜L then;

(2) if there is T _AConstantly, then further determine T _CConstantly;

(a) if there is T _CConstantly, Q=L+n then _j/ k _j

(b) if there is not T _CConstantly, then red light of following cycle is opened the bright moment

As transition moment T _C, statistics T _BWith

Pass through the vehicle number n of detecting device in time period _j, Q＞L+n then _j/ k _j

Step 4, the signal control strategy of adjustment major trunk roads, detailed process is as described below:

Calculate craspedodrome queue length Q according to the method for step 3 respectively _SWith the queue length Q that turns left _L

(1) if the length of two formations all less than L, then turn left phase time and craspedodrome phase time all distribute minimum green time, i.e. T _G1=T _G2=G _Min

(2) if having only a certain queue length less than L, the minimum green time T of the phase assignments at this formation place then _G1=G _Min, another length needs then to determine more than or equal to the formation of L whether this formation exists transition T constantly _C:

(a) if there is transition T constantly _C, then according to T _CWith

Calculate interior vehicle of this time interval by the required minimum speed v of L _m, then have $v_m=L/(T_R^{n+1}-T_C),$ Determine whether to exist green light to have more than needed the time:

A) if v _m＜v then exists green light to have more than needed the time, with the former green light duration green light change time g of the unit of cutting _Lay, i.e. T _G2=T _G2-g _Lay

B) if v _m〉=v does not then exist green light to have more than needed the time, i.e. expression has residual queue, if T _G2＜G _Main-T _G1, then add g at former green light duration _Lay, i.e. T _G2=T _G2+ g _Lay, if T _G2=G _Main-T _G1, T then _G2=T _G2

(b) if there is not transition T constantly _C, when then being illustrated in the green time end, the detecting device upstream also has queue queue, and then the green light duration of this phase place is T _G2=G _Main-T _G1

(3) if, then determining individual queue all more than or equal to L, the queue length of two formations whether has transition T constantly _C, then have:

(a) if there is T constantly in the both _C, determine then whether each phase place has green time more than needed, according to the strategy (a) of step (2) carry out green light prolong or reduce green light duration T _G1And T _G2, wherein: T _G1+ T _G2≤ G _Main

(b) if there is T constantly in a formation _C, there is not T constantly in another _C, then have T constantly _CPhase place according to the strategy (a) of step (2) carry out green light prolong or reduce green light duration T _G1, do not have T constantly _CThe green time of phase place be T _G2=G _Main-T _G1

(c) if neither there is transition T constantly _C, then according to Q _SAnd Q _LLength ratio distribute the green time of turn left phase place and craspedodrome phase place, namely $\left\{\begin{array}{c}{T}_L=G_{\mathrm{main}}\×\frac{Q_L}{Q_L+Q_S}\\ T_S=G_{\mathrm{main}}\×\frac{Q_S}{Q_L+Q_S}\end{array}\right.$

Wherein: T _LBe the green light duration of phase place of turning left, T _SBe the green light duration of craspedodrome phase place, Q _SBe craspedodrome phase place queue length, Q _LIt is the phase place queue length of turning left.

Step 5, the signal control strategy of adjustment subsidiary road, detailed process is as described below:

Subsidiary road is kept straight on and is turned left and controlled by a phase place, note G _MinorBe the maximum green time of subsidiary road, G _MinBe minimum green time, g _LayFor the unit green light prolongs or the shortening time, at first calculate the queue length Q of subsidiary road according to the method for step 3;

(1) if queue length Q＜L then distributes Minimum Green Time T _g=G _Min

(2) if queue length Q 〉=L then determines whether to exist transition T constantly _C, then have:

(a) if there is transition T constantly _C, then according to T _CWith

Calculate interior vehicle of this time interval by the required minimum speed v of L _m, then have $v_m=L/(T_R^{n+1}-T_C),$ Determine whether to exist green light to have more than needed the time:

A) if v _m＜v then exists green light have more than needed time, then T _g=T _g-g _Lay

B) if v _m〉=v does not then exist green light to have more than needed the time, i.e. expression has residual queue, if T _g＜G _Minor, T then _g=T _g+ g _Lay, if T _g=G _Minor, T then _g=T _g

(b) if there is not transition T constantly _C, T then _g=G _Minor

The present invention compared with prior art, beneficial effect is:

Method of the present invention utilizes the wagon detector of having laid in the city to obtain traffic flow data, calculates the queue length in each track, dynamically adjusts the signal time distributing conception of following one-period according to the different proportion of queue length.This method is the calculating that unit carries out the timing scheme with the cycle, and operand is little, and can reach intersection signal is realized adaptive control according to vehicle density purpose.In addition, this method algorithm is simple, and is lower to hardware and quantities requirement, do not increase construction cost by existing device, the convenient popularization.

Description of drawings

Fig. 1 is main and secondary road crossing wagon detector schematic layout pattern.

Fig. 2 is the time dependent synoptic diagram of vehicle queue queue on the track.

There is transition T constantly in Fig. 3 in the vehicle queue formation evanishment _CAnd the time dependent synoptic diagram of the formation that green time more than needed is arranged.

There is transition T constantly in Fig. 4 in the vehicle queue formation evanishment _CBut the time dependent synoptic diagram of formation of the green time of not having more than needed.

There is not transition T constantly in Fig. 5 in the vehicle queue formation evanishment _CThe time dependent synoptic diagram of formation.

Fig. 6 is major trunk roads signal adaptive control flow chart.

Fig. 7 is subsidiary road signal adaptive control flow chart.

Below in conjunction with drawings and Examples particular content of the present invention is done explanation in further detail.

Embodiment

The dimension that need to prove the physical quantity that present embodiment provides is the unified standard dimension in this area, and those skilled in the art are according to i.e. its dimension as can be known of physical quantity, and therefore following content provides no longer one by one.

Need to prove that one-period is to open from red light to be carved into green light when bright and to extinguish constantly, according to existing traffic rules, stop line can not pass through with interior vehicle during the amber light flicker, so the flicker duration of amber light is grouped into red light duration the inside in the lump among the present invention, will no longer consider amber light among the following embodiment.

Defer to technique scheme, as shown in Figure 1, it is main and secondary road crossing wagon detector schematic layout pattern, east-west direction is major trunk roads among the figure, craspedodrome road at distance crossing La is equipped with wagon detector with turning left, North and South direction is subsidiary road, and the Ls place is equipped with wagon detector in the distance crossing.Major trunk roads are provided with turn left phase place and craspedodrome phase place, and subsidiary road is kept straight on and turned left by a phase control.Crossing is provided with signal controller, and all wagon detectors are implemented the volume of traffic, detecting device holding time, free time is detected and be transferred to the back-end data disposal system.The Real-Time Data Handling System (RTDHS) on backstage is dynamically determined the signal time distributing conception of following one-period according to result of calculation, and is transferred to signal controller.

Because the vehicle queue length computing method of major trunk roads and subsidiary road are identical, so following proposal is that example is controlled with an arterial highway, and the distance of detector distance stop line is L.

Be a time dependent synoptic diagram of track queue queue as shown in Figure 2, when red light open bright after, the vehicle queuing that begins to stop is opened when bright until green light, queue queue begins to dissipate, and goes round and begins again like this.When transition T does not constantly appear in red light in the time period _APoint illustrates queue length Q＜L, otherwise, account for queued formation overflow detector.According to

To T _AThe vehicle number n of the queuing in the time period _LCalculate the vehicle density under the saturated conditions:

k _j＝n _L/L

Open the bright moment from green light

To moment T _B, formation is rolled the crossing away from saturation volume rate, and the dissipation speed of formation is:

$v=L/(T_B-T_G^n)$

Be to have transition T constantly in queue queue's evanishment as shown in Figure 3 _CAnd the time dependent synoptic diagram of the formation that green time more than needed is arranged; Shown in Figure 4 is to have transition T constantly in queue queue's evanishment _CBut the time dependent synoptic diagram of formation of the green time of not having more than needed.According to T _CWith

Interval calculation

If v _mThen there is green time more than needed in＜v as Fig. 3; If v _mThen there is not green time more than needed in 〉=v as Fig. 4.Utilize T _BAnd T _CTime period, interior vehicle number n by wagon detector calculated the maximum queue length in this cycle:

Q＝L+n/k _j

Be not have transition T constantly in queue queue's evanishment as shown in Figure 5 _CThe time dependent synoptic diagram of formation, T constantly _CDo not exist to show that detector back also has waiting list when effective green time finishes, this moment will

Regard T as _C, statistics T _BWith

Pass through the vehicle number n of detecting device in time period _j, then queue length is:

Q＞L+n _j/k _j

Next, determine the parameter in the control scheme, because an intersection signal cycle can not be long or too short, if it is too short, then each phase place is switched frequently, and the increase of vehicle parking number and vehicle are started to walk continually and stopped, if long, then the time of vehicle wait is just long in the queue queue, therefore establishes minimum green time G in this programme _Min(being generally 15s), the green light change time g of unit _Lay(3s), maximum total green time G of major trunk roads _Main(being generally 80s), the maximum green time G of subsidiary road _Minor(being generally 45s).

Be major trunk roads signal adaptive control flow chart as shown in Figure 6, at first calculate craspedodrome queue length Q _SWith the queue length Q that turns left _L, carry out signal controlling according to following steps then:

(1) if the length of two formations all less than L, the phase place of then turning left and craspedodrome phase place are all distributed minimum green time, i.e. T _G1=T _G2=G _Min

(2) if a certain queue length less than L, the minimum green time T of this phase assignments then _G1=G _Min, and the length of another formation determines then more than or equal to L whether this formation exists T _C:

(a) if there is transition T constantly _C, then according to T _CWith The time interval calculate in this time interval vehicle by the required minimum speed of L $v_m=L/(T_R^{n+1}-T_C),$ Determine whether to exist green light to have more than needed the time

A) if v _m＜v exists the green light time more than needed then with the former green light duration green light change time g of the unit of cutting _Lay, i.e. T _G2=T _G2-g _Lay

B) if v _m〉=v does not exist the green light time more than needed then to represent to have residual queue, if T _G2＜G _Main-T _G1, then add the green light change time g of unit at former green light duration _Lay, i.e. T _G2=T _G2+ g _Lay, if T _G2=G _Main-T _G1, T then _G2=T _G2

(b) if there is not transition T constantly _C, illustrate that then when green time finished, the detecting device upstream also had queue queue, then the green light duration of this phase place is T _G2=G _Main-T _G1

(3) if whether existence transition T constantly of individual queue, is then determined in the queue length of two formations all more than or equal to L _C:

(a) if there is transition T constantly in the both _C, determine then whether each phase place has green time more than needed, carry out green light according to the strategy (a) of step (2) and prolong or reduce;

(b) if one exists transition T constantly _C, one does not exist, then exist transition phase place constantly according to the strategy (a) of step (2) carry out green light prolong or reduce green light duration T _G1, the green time of another phase place is T _G2=G _Main-T _G1

(c) if neither there is transition T constantly _C, then according to Q _SAnd Q _LLength ratio distribute the green time of turn left phase place and craspedodrome phase place, namely $\left\{\begin{array}{c}{T}_L=G_{\mathrm{main}}\×\frac{Q_L}{Q_L+Q_S}\\ T_S=G_{\mathrm{main}}\×\frac{Q_S}{Q_L+Q_S}\end{array}\right..$

Wherein: T _LBe the green light duration of phase place of turning left, T _SBe the green light duration of craspedodrome phase place, Q _SBe craspedodrome phase place queue length, Q _LIt is the phase place queue length of turning left.

Be subsidiary road signal adaptive control flow chart as shown in Figure 7, subsidiary road is kept straight on and is turned left by a phase control, thus at first calculate the queue length Q of subsidiary road,

1) if queue length Q＜L then distributes Minimum Green Time T _g=G _Min

2) if queue length Q 〉=L then determines whether to exist transition T constantly _C

(a) if there is transition T constantly _C, then according to T _CWith

Calculate interior vehicle of this time interval by the required minimum speed v of L _m, then have

Determine whether to exist green light to have more than needed the time:

A) if v _m＜v then exists green light have more than needed time, then T _g=T _g-g _Lay

B) if v _m〉=v does not then exist green light to have more than needed the time, i.e. expression has residual queue, if T _g＜G _Minor, T then _g=T _g+ g _Lay, if T _g=G _Minor, T then _g=T _g

(b) if there is not transition T constantly _C, T then _g=G _Minor

Below provide specific embodiments of the invention, need to prove that the present invention is not limited to following specific embodiment, all equivalents of doing on present techniques scheme basis all fall into protection scope of the present invention.

Embodiment:

As the cross junction among Fig. 1, it is major trunk roads that east-west direction is set, and wagon detector is apart from the distance L of stop line _a=80m, North and South direction is subsidiary road, wagon detector is apart from the distance L of stop line _b=60m, the maximum total green light duration G of major trunk roads _MainBe 80s, the maximum green light duration of subsidiary road G _MinorBe 45s, minimum green light duration G _MinBe 15s, the green light change duration g of unit _LayBe 3s.

As shown in table 1ly begin the timing state of resulting signal lamp for present embodiment from 10:00:00.

Suppose constantly

Be red light zero hour of major trunk roads, statistics is obtained the wagon detector data in cycle and signal lamp phase tranformation data as craspedodrome road transition moment point T at the moment _A9:59:10, the transition of craspedodrome road is T constantly _B9:59:24, the transition of craspedodrome road is T constantly _C9:59:30, craspedodrome green light zero hour

Turn left green light zero hour

To T _APass through the equivalent vehicle number n of wagon detector in time _L=20, T _BTo T _CEquivalent vehicle number by wagon detector in time is n _j=2, turning left does not exist transition T constantly _A, T _B, T _CCalculate saturation flow density: k _j=n _L/ L _a=20/80=0.25, formation dissipation speed $v=L_a/(T_B-T_{G,S}^0)=80/(24-14)=8m/s$ With $v_m=L_a/(T_{G,L}^0-T_C)=80/(44-30)=5\·71m/s,$ Because v _m＜v has green time more than needed, queue length Q _S=L _a+ n _j/ k _j=80+2/0.25=88m, therefore craspedodrome of following cycle green light duration T _S=T _S-g _Lay=30s-3s=27s, the green light duration of turning left is T _L=G _Min=15s.

And constantly

Be the red light zero hour of subsidiary road, statistics is obtained the wagon detector data in cycle and signal lamp phase tranformation data as green light zero hour at the moment

Be 10:00:00, green light duration T _GBe 30s, do not have transition moment point T _A, therefore the green light duration in following cycle is T _G=G _Min=15s;

Constantly Be another red light of major trunk roads zero hour, statistics is obtained the wagon detector data in cycle and signal lamp phase tranformation data as craspedodrome green light zero hour at the moment

Be 10:00:31, do not have transition moment point T _A, the red light zero hour of turning left

Be 10:00:00, the transition moment point of turning left T _A10:00:47, the transition of turning left is T constantly _B10:01:08, the transition of turning left is T constantly _C10:01:11, the green light zero hour of turning left

To T _APass through the equivalent vehicle number n of wagon detector in time _L=19, T _BTo T _CEquivalent vehicle number by wagon detector in time is n _j=1.Calculating track saturation flow density: the k that turns left _j=n _L/ L _a=19/80=0.23, formation dissipation speed $v=L_a/(T_B-T_{G,L}^1)=80/10=8m/s$ With $v_m=L_a/(T_{R,L}^2-T_C)=80/2=40m/s,$ Because v _m

V green time not more than needed, Q _L=L _a+ n _j/ k _j=80+1/0.23=84m, therefore craspedodrome of following cycle green light duration is T _S=G _Min=15s, the green light duration of turning left is T _L=T _L+ g _Lay=15s+3s=18s;

Constantly Be another red light of subsidiary road zero hour, statistics is obtained the wagon detector data in cycle and signal lamp phase tranformation data as the red light start time at the moment

Be 10:00:31, transition is T constantly _ABe 10:01:02, green light zero hour

Be 10:01:13, transition is T constantly _BBe 10:01:21, transition is T constantly _CBe 10:01:25, To T _APass through the equivalent vehicle number n of wagon detector in time _L=14, T _BTo T _CEquivalent vehicle number by wagon detector in time is n _j=3.Calculate track saturation flow density: k _j=n _L/ L _b=14/60=0.23, formation dissipation speed $v=L_b/(T_B-T_G^1)=60/8=7\·5m/s$ With $v_m=L_b/(T_{R,C}^2-T_C)=60/4=15m/s,$ Because v _m＞v, green time not more than needed, Q=L _b+ n _j/ k _j=60+3/0.23=73m, therefore green light duration of following cycle is T _G=T _G+ g _Lay=15s+3s=18s;

Constantly

Be the another red light zero hour of major trunk roads, statistics is obtained the wagon detector data in cycle and signal lamp phase tranformation data as the transition moment T in craspedodrome road at the moment _ABe 10:01:20, green light zero hour

Be 10:01:28, transition is T constantly _BBe 10:01:38, transition is T constantly _CBe 10:01:42,

To T _APass through the equivalent vehicle number n of wagon detector in time _L=18, T _BTo T _CEquivalent vehicle number by wagon detector in time is n _j=2.Calculate Through Lane saturation flow density: k _j=n _L/ L _a=18/80=0.225, formation dissipation speed $v=L_a/(T_B-T_{G,S}^2)=80/10=8m/s$ With $v_m=L_a/(T_{G,L}^2-T_C)=80/1=80m/s,$ Because v _m

V, green time not more than needed, queue length Q therefore keeps straight on _S=L _a+ n _j/ k _j=80+2/0.225=88m; The transition of turning left is T constantly _ABe 10:01:27, green light zero hour

Be 10:01:43, transition is T constantly _BBe 10:01:55, do not have transition T constantly _C,

To T _BPass through the equivalent vehicle number n of wagon detector in time _L=20, T _BExtremely

Equivalent vehicle number by wagon detector in time is n _j=4, calculate track saturation flow density: the k that turns left _j=n _L/ L _a=20/80=0.25, formation dissipation speed $v=L_a/(T_B-T_{G,L}^2)=80/12=6\·66m/s,$ Therefore queue length Q turns left _L＞L _a+ n _j/ k _j=80+4/0.25=96m, therefore craspedodrome of following cycle green light duration T _S=T _S+ g _Lay=15s+3s=18s, the green light duration of turning left is T _L=G _Main-T _S=80s-18s=62s;

Constantly

Be the another red light zero hour of subsidiary road, statistics is obtained the wagon detector data in cycle and signal lamp phase tranformation data as the transition moment T of subsidiary road this moment _ABe 10:01:45, green light zero hour

Be 10:02:01, transition is T constantly _BBe 10:02:10, do not have transition T constantly _C, To T _BPass through the equivalent vehicle number n of wagon detector in time _L=14, T _BExtremely

Equivalent vehicle number by wagon detector in time is n _j=11, calculate track saturation flow density of last cycle: k _j=n _L/ L _b=14/60=0.23, queue length Q＞L _b+ n _j/ k _j=60+11/0.23=108m when Effective Green Time finishes, still has formation behind the wagon detector, therefore the green light duration in following cycle is T _G=G _Minor=45s;

Constantly Be another red light zero hour of major trunk roads, statistics is obtained the wagon detector data in cycle and signal lamp phase tranformation data as craspedodrome road transition moment T this moment _ABe 10:02:03, green light zero hour

Be 10:02:19, transition is T constantly _BBe 10:02:30, do not have transition T constantly _C,

To T _BPass through the equivalent vehicle number n of wagon detector in time _L=19, T _BExtremely

Equivalent vehicle number by wagon detector in time is n _j=14, calculate Through Lane saturation flow density of last cycle: k _j=n _L/ L _a=19/80=0.2375, queue length Q _S＞L _a+ n _j/ k _j=80+14/0.2375=139m; The transition of turning left is T constantly _ABe 10:02:29, green light zero hour

Be 10:02:37, transition is T constantly _BBe 10:02:55, do not have transition T constantly _C,

To T _BInterior equivalent vehicle number n by detecting device _L=20, T _BExtremely

Interior equivalent vehicle number n by wagon detector _j=27, track saturation flow density: the k that turns left of the last cycle of calculating _j=n _L/ L _a=20/80=0.25 queuing queue Q _L＞L _a+ n _j/ k _jWhen=80+27/0.25=188m finishes at Effective Green Time, all still have formation behind the detecting device in two tracks, therefore craspedodrome of following cycle green light duration is

$T_S=G_{\mathrm{main}}\×\frac{Q_S}{Q_S+Q_L}=80s\×\frac{139m}{139m+180m}=35s,$ The green light duration of turning left is

$T_L=G_{\mathrm{main}}\×\frac{Q_L}{Q_S+Q_L}=80s\×\frac{188m}{139m+188m}=45s;$

Constantly

Be another red light zero hour of subsidiary road, this moment statistics obtain the wagon detector data in cycle and signal lamp phase tranformation data as: the track transition moment is T this moment _ABe 10:03:05, green light zero hour Be 10:03:39, transition is T constantly _BBe 10:03:50, transition is T constantly _CBe 10:03:58, To T _BEquivalent vehicle number by wagon detector in time is n _L=14, T _BTo T _CEquivalent vehicle number by wagon detector in time is n _j=8, calculating track saturation flow density of last cycle is k _j=n _L/ L _b=14/60=0.23, queue length Q=L _b+ n _j/ k _j=60+8/0.23=94m, formation dissipation speed $v=L_b/(T_B-T_G^3)=60/11=5\·45m/s,$ Formation is dissipated fully, again $v_m=L_b/(T_{R,C}^4-T_C)=60/26=2\·3m/s,$ v _m＜v has green time more than needed, then the green light duration T in following cycle _G=T _G-g _Lay=45s-3s=42s;

Constantly

Be red light zero hour of major trunk roads, statistics is obtained the wagon detector data in cycle and signal lamp phase tranformation data as craspedodrome road transition moment T this moment _ABe 10:03:50, green light zero hour

Be 10:04:59, transition is T constantly _BBe 10:04:35, transition is T constantly _CBe 10:04:40,

To T _BEquivalent vehicle number by wagon detector in time is n _L=20, T _BTo T _CEquivalent vehicle number by wagon detector is n _j=2, calculate the craspedodrome road saturation flow density k in last cycle _j=n _L/ L _a=20/80=0.25, formation dissipation speed $v=L_a/(T_B-T_{G,S}^4)=80/11=7\·27m/s,$ Formation is dissipated fully, again $v_m=L_a/(T_{G,C}^4-T_C)=80/19=4\·21m/s,$ v _m＜v has green time more than needed, queue length Q _S=L _a+ n _j/ k _j=80+2/0.25=88m; The transition of turning left is T constantly _ABe 10:04:38, green light zero hour

Be 10:04:59, transition is T constantly _BBe 10:05:20, do not have transition T constantly _C,

To T _BEquivalent vehicle number by wagon detector in time is n _L=21, T _BExtremely

Equivalent vehicle number by wagon detector in time is n _j=20, the saturation flow density k that turns left of the last cycle of calculating _j=n _L/ L _a=21/80=0.26, queue length Q _L＞L _a+ n _j/ k _j=80+20/0.26=157m when Effective Green Time finishes, still has formation behind the detecting device, therefore the craspedodrome green light duration T in following cycle _S=T _S-g _Lay=36s-3s=33s, the green light duration of turning left is T _L=G _Main-T _S=80s-33s=47s.

Table 1 begins the timing state of resulting signal lamp from 10:00:00

Period	The signal lamp state	Duration (s)
			10:00:00-10:00:30	Major trunk roads are kept straight on, all red lights of turning left, the subsidiary road green light	30
10:00:31-10:00:57	Major trunk roads craspedodrome green light, the red light of turning left, the subsidiary road red light	27
			10:00:58-10:01:12	Major trunk roads craspedodrome red light, the green light of turning left, the subsidiary road red light	15
10:01:13-10:01:27	Major trunk roads are kept straight on, all red lights of turning left, the subsidiary road green light	15
			10:01:28-10:01:42	Major trunk roads craspedodrome green light, the red light of turning left, the subsidiary road red light	15
10:01:43-10:02:00	Major trunk roads craspedodrome red light, the green light of turning left, the subsidiary road red light	18
			10:02:01-10:02:18	Major trunk roads are kept straight on, all red lights of turning left, the subsidiary road green light	18
10:02:19-10:02:36	Major trunk roads craspedodrome green light, the red light of turning left, the subsidiary road red light	18
			10:02:37:10:03:38	Major trunk roads craspedodrome red light, the green light of turning left, the subsidiary road red light	62
10:03:39-10:04:23	Major trunk roads are kept straight on, all red lights of turning left, the subsidiary road green light	45
			10:04:24-10:04:58	Major trunk roads craspedodrome green light, the red light of turning left, the subsidiary road red light	35
10:04:59-10:05:44	Major trunk roads craspedodrome red light, the green light of turning left, the subsidiary road red light	45
			10:05:45-10:06:26	Major trunk roads are kept straight on, all red lights of turning left, the subsidiary road green light	42
10:06:27-10:06:59	Major trunk roads craspedodrome green light, the red light of turning left, the subsidiary road red light	33
			10:07:00-10:07:47	Major trunk roads craspedodrome red light, the green light of turning left, the subsidiary road red light	47

Claims (1)

1. adaptive intersection signal control method is characterized in that this method is carried out according to following steps:

Step 1,1 wagon detector is installed in each track in the crossing, and the distance of vehicle sensors and stop line is designated as L, and each wagon detector is used for gathering the red light in each phase place n cycle and opens the bright moment

The green light in n cycle opens the bright moment

The red light in n+1 cycle opens the bright moment

Holding time t when each vehicle passes through wagon detector _o, wagon detector free time t at interval _fReach the vehicle number n by detecting device;

Described phase place comprises the phase place of turning left at the craspedodrome phase place at craspedodrome formation place and the formation place of turning left;

One-period is carved into green light when bright for opening from red light and extinguishes constantly note G _MinBe minimum green time, note g _LayFor the unit green light prolongs or the shortening time, note G _MainMaximum total green time for major trunk roads;

Step 2, when the one-period effective green time finishes, wagon detector will detect data transmission and give the back-end data disposal system, analyze the variation of traffic behavior in this cycle, find out the transition moment T of wagon detector eigenstate _A, T _BAnd T _C

T _ABe that red light opens bright back vehicle v ₁Beginning takies the transition between states moment of wagon detector, T for a long time _AConstantly, wagon detector is by vehicle v ₁Take for a long time, constantly T _ACan be used to determine whether this phase place track exists long vehicle formation;

T _BBe that green light opens bright back vehicle v ₁Sail out of the transition of wagon detector constantly, green light open bright after, T _BConstantly, the vehicle before the stop line sails out of the crossing with saturation volume rate successively, but is 0 by the vehicle number of detecting device, at T _BAfterwards, by wagon detector, reduce by the holding time of wagon detector and interval time with the current flow rate of maximum for vehicle;

T _CBe last car v in the vehicle queue formation ₂By the transition between states moment of wagon detector, determine last car of formation v ₂Foundation be: in the queue queue continuously during the vehicle passing detection device interval time less, when a car and its Following Car pass through detecting device interval greater than threshold value A, illustrate in not Queue here of the Following Car formation;

The value that obtains threshold value A according to present traffic study data statistics result is 3s;

Step 3, adopt from

The time be carved into T _APass through the vehicle number n of detecting device in time period constantly _LCalculate the vehicle density k under the saturated conditions _j, k then _j=n _L/ L; Employing from The time be carved into T _BTime period and stop line calculate the dissipation speed v of vehicle queue formation to the distance L between wagon detector constantly, then

And then pass through T _BAnd T _CPass through the vehicle number n of detecting device in time period _jCalculate the maximum queue length Q in this cycle;

(1) if there is not T _AConstantly, Q＜L then;

(2) if there is T _AConstantly, then further determine T _CConstantly;

(a) if there is T _CConstantly, Q=L+n then _j/ k _j

(b) if there is not T _CConstantly, then red light of following cycle is opened the bright moment

As transition moment T _C, statistics T _BWith

Pass through the vehicle number n of detecting device in time period _j, Q＞L+n then _j/ k _j

Step 4, the signal control strategy of adjustment major trunk roads, detailed process is as described below:

Calculate craspedodrome queue length Q according to the method for step 3 respectively _SWith the queue length Q that turns left _L

(1) if the length of two formations all less than L, then turn left phase time and craspedodrome phase time all distribute minimum green time, i.e. T _G1=T _G2=G _Min

(2) if having only a certain queue length less than L, the minimum green time T of the phase assignments at this formation place then _G1=G _Min, another length needs then to determine more than or equal to the formation of L whether this formation exists transition T constantly _C:

(a) if there is transition T constantly _C, then according to T _CWith Calculate interior vehicle of this time interval by the required minimum speed v of L _m, then have

Determine whether to exist green light to have more than needed the time:

A) if v _m＜v then exists green light to have more than needed the time, with the former green light duration green light change time g of the unit of cutting _Lay, i.e. T _G2=T _G2-g _Lay

B) if v _m〉=v does not then exist green light to have more than needed the time, i.e. expression has residual queue, if T _G2＜G _Main-T _G1, then add g at former green light duration _Lay, i.e. T _G2=T _G2+ g _Lay, if T _G2=G _Main-T _G1, T then _G2=T _G2

(b) if there is not transition T constantly _C, when then being illustrated in the green time end, the detecting device upstream also has queue queue, and then the green light duration of this phase place is T _G2=G _Main-T _G1

(3) if, then determining individual queue all more than or equal to L, the queue length of two formations whether has transition T constantly _C, then have:

(a) if there is T constantly in the both _C, determine then whether each phase place has green time more than needed, according to the strategy (a) of step (2) carry out green light prolong or reduce green light duration T _G1And T _G2, wherein: T _G1+ T _G2≤ G _Main

(b) if there is T constantly in a formation _C, there is not T constantly in another _C, then have T constantly _CPhase place according to the strategy (a) of step (2) carry out green light prolong or reduce green light duration T _G1, do not have T constantly _CThe green time of phase place be T _G2=G _Main-T _G1

(c) if neither there is transition T constantly _C, then according to Q _SAnd Q _LLength ratio distribute the green time of turn left phase place and craspedodrome phase place, namely $\left\{\begin{array}{c}{T}_L=G_{\mathrm{main}}\×\frac{Q_L}{Q_L+Q_S}\\ T_S=G_{\mathrm{main}}\×\frac{Q_S}{Q_L+Q_S}\end{array}\right.$

Wherein: T _LBe the green light duration of phase place of turning left, T _SBe the green light duration of craspedodrome phase place, Q _SBe craspedodrome phase place queue length, Q _LIt is the phase place queue length of turning left.

Step 5, the signal control strategy of adjustment subsidiary road, detailed process is as described below:

Subsidiary road is kept straight on and is turned left and controlled by a phase place, note G _MinorBe the maximum green time of subsidiary road, G _MinBe minimum green time, g _LayFor the unit green light prolongs or the shortening time, at first calculate the queue length Q of subsidiary road according to the method for step 3;

(1) if queue length Q＜L then distributes Minimum Green Time T _g=G _Min

(2) if queue length Q 〉=L then determines whether to exist transition T constantly _C, then have:

(a) if there is transition T constantly _C, then according to T _CWith

Calculate interior vehicle of this time interval by the required minimum speed v of L _m, then have Determine whether to exist green light to have more than needed the time:

A) if v _m＜v then exists green light have more than needed time, then T _g=T _g-g _Lay

B) if v _m〉=v does not then exist green light to have more than needed the time, i.e. expression has residual queue, if T _g＜G _Minor, T then _g=T _g+ g _Lay, if T _g=G _Minor, T then _g=T _g

(b) if there is not transition T constantly _C, T then _g=G _Minor

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