CN104332058B - A kind of Intelligent traffic light control method and system - Google Patents

Abstract

The invention discloses a kind of intelligent Control System for Traffic Lights, including monitoring camera, traffic lights and countdown lamp, also include that intersection vehicle flux detection microprocessor, Traffic Signal Timing adjust automatically calculate microprocessor, driver module, Digital Image Processor, I/O interfaces, the signal timing dial of controller adjust automatically traffic lights, the green light utilization rate of crossing all directions is made to compare with wagon flow, increased or decrease by identical trend, the traffic conditions at effective Dynamic Recognition crossing, automatic regulating signal timing, reduces congestion.

Description

A kind of Intelligent traffic light control method and system

Technical field

The present invention relates to the intelligent transportation lamp controller in field of traffic, more particularly to field of traffic.

Background technology

Currently, the urban transit system situation of the main big and medium-sized cities of China all allows of no optimist, and vehicle is more, and road is blocked up, Vehicular exhaust Exhaust emission is serious, and these have become a key factor of restriction socio-economic development to a certain extent.Chinese science The achievement in research of strategy of sustainable development seminar of institute expert shows that, because of traffic congestion and problem of management, 15 cities of China are every Its nearly 1,000,000,000 yuan of wealth of loss.In addition, the traffic of congestion is also easy to the bad mental emotion for causing driver, increased and hand over The probability of interpreter's event.

It is an effective way for solving current city traffic predicament with advanced technology, by advanced technology, can be with The potential of existing means of transportation is fully excavated, and the transport for undertaking people as much as possible and thing with limited traffic resource, to solve Contradiction between the continuous growth of transport need and traffic resource scarcity.There is in terms of urban traffic blocking is solved vertical pole to see for which One application of shadow effect is exactly to install intelligent traffic light in road grade crossing to replace traditional traffic lights.Traditional traffic Lamp is using fixed signal period and split, it is impossible to which the dynamic change according to crossing traffic flow is automatically adjusted, and is often existed The situation of the short crossing without car or few car of crossing green light transit time more than car but light yellow green light, the traffic capacity at crossing are unrestrained Fei Liao.And intelligent traffic lamp can be according to the real-time change of crossing traffic flow, using corresponding intelligent control algorithm dynamic The parameter of regulation traffic signal lamp, makes to shorten dramatically by the stand-by period of crossing vehicle, and the traffic efficiency at crossing is improved.

Although intelligent traffic lamp has so attracting advantage, researcher also to carry out research to this, designed Some intelligent traffic lamp control programs, but at this stage, it is not promoted the use of on a large scale, is traced it to its cause, Mainly existing Intelligent traffic light control method needs the vehicle waiting number of real-time detection crossing direction to the car, and this requirement exists Two wagon detectors are installed in the place of every track stop line rear separated by a distance two, and by the vehicle number for detecting According to traffic signal control is transferred to, the quantities which is installed is larger, and the traffic of construction section can be impacted, and also has Existing road surface may be destroyed, the fund input of needs is also relatively more.Wagon detector mainly have ultrasonic wave, infrared, microwave radar, The types such as ground induction coil, all kinds of detectors respectively have quality, and which selects also ununified standard.Above-mentioned a variety of factors cause traffic Administrative department is difficult to reach a decision, and intelligent transportation lamp controller is installed in the unification at crossing.

For above-mentioned difficulties, the invention discloses a kind of level-crossing intelligent traffic light scheme, its core concept is to fill Divide the crossing existing hardware equipment that utilizes, only need to change traffic signal controlling machine, be simultaneously connected with the high-definition camera video letter at crossing Number, using corresponding image procossing and traffic light signals duration dynamic regulation algorithm, realize the dynamic regulation of signal lamp.Which is transformed Relate only to change traffic signal controlling machine and connection crossing camera video signal, can enter around the control cabinet in roadside OK, traffic will not be blocked.And the time of installation and debugging is very short, may be selected to carry on construction work at night.Or construction on daytime, using movement Formula traffic lights temporary control and education crossing traffic.Its transformation process is convenient and swift, and equipment cost is little.

Content of the invention

A kind of intelligent transportation lights control scheme, using the existing monitoring camera of road grade crossing, gathers crossing and hands over The video information of logical situation, the traffic flow data for obtaining crossing all directions using image processing algorithm.Controller is counted according to this According to the algorithm with setting, the signal timing dial of adjust automatically traffic lights makes the green light utilization rate of crossing all directions compare with wagon flow, Increased or decrease by identical trend, the concrete scheme of the present invention is as follows：

A kind of intelligent Control System for Traffic Lights is set, including monitoring camera, traffic lights and countdown lamp, described System also includes that intersection vehicle flux detection microprocessor, Traffic Signal Timing adjust automatically calculate microprocessor, show driving mould Block, Digital Image Processor, I/O interfaces：

Monitoring camera sends the video of acquisition to Digital Image Processor, and Digital Image Processor carries out image procossing Afterwards result is exported to intersection vehicle flux and detects microprocessor, the intersection vehicle flux detection microprocessor is through processing To information of vehicle flowrate and send to Traffic Signal Timing adjust automatically calculate microprocessor, the Traffic Signal Timing adjust automatically Microprocessor is calculated after processing and obtaining signal timing dial result, I/O interfaces and driver module is called, signal timing dial is tied Fruit is exported to traffic lights and countdown lamp.

The intersection vehicle flux detection microprocessor obtains information of vehicle flowrate using following steps：

A) identify in one signal period of traffic lights by the number of vehicles and vehicle of crossing all directions；

B) according to the length ratio of large car and compact car, equivalent kart number is converted into；

C the number is obtained the vehicle flowrate n in the per share track of the direction divided by the number of track-lines of the crossing direction)_i.

The Traffic Signal Timing adjust automatically calculates microprocessor（4）The signal for adopting adjustment traffic lights with the following method is matched somebody with somebody When：

A) both direction at note crossing is respectively x and y, if the signal period of traffic lights is t, containing four phase places, point Not Wei x directions straight trip, x directions turn left, y directions straight trip, y directions turn left, its phase place duration is respectively t₁、t₂、t₃And t₄, then The formula of arriving（1）：

t=t₁+t₂+t₃+t₄(1)

B）If the magnitude of traffic flow number that single track averagely passes through during each phase place is respectively n₁、n₂、n₃And n₄, define green light Utilization rate η is the ratio of the magnitude of traffic flow that passes through of single track and long green light time, then the long green light time utilization rate of each green light phase place point It is not

(2)

The long green light time average utilization at crossing is

(3)

Generally, above-mentioned utilization rate unequal, i.e.,

(4)

C, at the end of) remembering a signal period, during the signal period for measuring, traffic parameter is t_i, (i=1,2,3,4) andThe then signal duration basic value t of each phase place of next signal period_i', (i=1,2,3,4) it is

(5)

t_i' and t_iBetween relation meet

(6)

D) according to the actual conditions at crossing, each phase place should mutually have a minimum green time, be designated as t_gmin, according to above-mentioned t_i' And t_gminComparative result, the setting of each signal duration of next signal period considers in two kinds of situation：

（1）t_i'3t_gmin,(i=1,2,3,4)

Take t_i' for each phase place of next signal period signal duration, new signal period time-preserving, and each phase place Green light utilization rate desired value identical, be

（2）At least there is phase j, j ∈ { 1,2,3,4 } meet t'_j<t_gmin

Will be less than t_gminT_i' value is adjusted to t_gmin, its time for borrowing equably shares other phase places, for this purpose, first By t_i' (i=1,2,3, ascending sequence 4) is pressed, new sequence is designated as s_i, according to s_iWith t_gminRelation, adjusted accordingly Whole.

The general principle of technical scheme

1st, general structure

Intelligent transportation lamp controller described in this method, including intersection vehicle flux detection, Traffic Signal Timing adjust automatically meter Calculate, show the modules such as driving, overall framework is as shown in Figure of description 1.In figure, camera uses crossing crossing monitoring camera, Without the need for additionally installing；DSP（Digital Image Processing）Processor and intersection vehicle flux detection microprocessor are calculated according to image information Obtain vehicle flowrate microprocessor is calculated to Traffic Signal Timing adjust automatically；Microprocessor executes signal timing dial of the present invention certainly Dynamic adjustment algorithm, drives the traffic lights and countdown lamp at crossing, and is provided with corresponding I/O ports.

2nd, vehicle Flow Detection

Conventional traffic flow detecting method has the technology such as ground induction coil, ultrasonic wave, microwave, video.In the technical program, car Flow detector makes full use of crossing existing equipment, to reduce cost and installation difficulty.Consider the master of Current City Road Intersection is wanted to be equipped with monitoring camera, therefore this method adopts video car flow amount detection technique, mounted by crossing Camera, obtains information of vehicle flowrate with image processing algorithm.Image processing function is at the digital picture of one piece of special design Reason（DSP）Complete on circuit board, it receives crossing vision signal, carries out image procossing, obtains information of vehicle flowrate, and send to Microprocessor.

During image procossing, identify in one signal period of traffic lights first by the number of vehicles of crossing all directions and Vehicle；Secondly, according to the length ratio of large car and compact car, equivalent kart number is converted into；Finally, the number is removed With the number of track-lines of the crossing direction, the vehicle flowrate n in the per share track of the direction is obtained_i.

3rd, signal timing dial automatic adjusting method

By taking most universal cross level-crossing as an example, remember that the both direction at crossing is respectively x and y, if traffic The signal period of signal lamp is t, and containing four phase places, respectively x directions are kept straight on, x directions are turned left, y directions are kept straight on, y directions are turned left, Its phase place duration is respectively t₁、t₂、t₃And t₄, then

t=t₁+t₂+t₃+t₄

The magnitude of traffic flow number that single track averagely passes through during each phase place is respectively n₁、n₂、n₃And n₄, define green light and utilize Rate η is the ratio of the magnitude of traffic flow that passes through of single track and long green light time, then the long green light time utilization rate of each green light phase place is respectively

The long green light time average utilization at crossing is

Generally, above-mentioned utilization rate unequal, i.e.,

This method passes through the above-mentioned t of dynamic regulation_i, (i=1,2,3,4) reaching makes η_i, (i=1,2,3,4) and n_i,(i=1,2,3, 4) purpose increasedd or decreased by identical trend.At the end of one signal period of note, traffic during the signal period for measuring Parameter is t_i, (i=1,2,3,4) andThe then signal duration basic value t of each phase place of next signal period_i', (i=1,2,3,4) it is

Obviously, t_i' and t_iBetween relation meet

According to the actual conditions at crossing, each phase place should mutually have a minimum green time, be designated as t_gmin, according to above-mentioned t_i' and t_gminComparative result, the setting of each signal duration of next signal period considers in two kinds of situation.

（1）t_i'3t_gmin,(i=1,2,3,4)

Now, t is taken_i' for each phase place of next signal period signal duration, it is clear that new time signal period keeps not Become, and the green light utilization rate desired value of each phase place is identical, is

（2）At least there is phase j, j ∈ { 1,2,3,4 } meet t'_j<t_gmin

Now, determine new timing duration basic ideas when will be less than t_gminT_i' value is adjusted to t_gmin, its " borrow " Time equably shares other phase places.For this purpose, first by t_i' (i=1,2,3, ascending sequence 4) is pressed, new sequence is designated as s_i, according to s_iWith t_gminRelation, be adjusted correspondingly.

Summary（1）With（2）Situation, corresponding to signal timing dial algorithm overall flow such as Fig. 2 of a signal period Shown.

4th, the realization of signal timing dial adjust automatically algorithm

Computing that signal timing dial adjust automatically algorithm is related to is main and cumulative and division, and needs using multiple timings Device；For realizing that the time of algorithm is suitable with signal lamp signal period, typically in tens of seconds to 100 seconds or so, very Abundant.Adjust automatically algorithm is realized by microprocessor, in addition, showing that driving, I/O interfaces are also required to microprocessor to manage（See Fig. 1）, thus, microprocessor is from the product that speed is not high but peripheral hardware aboundresources, reliability are high.

Field conduct step

By after the good traffic light controller of the principle design, its in-site installation is simple, it is only necessary to install traffic signals in roadside The control machine that the position of lamp controller more renews, connects the video monitoring signal at crossing to control machine, connects the output of control machine Signal arranges initial parameter, it is possible to bring into operation, as shown in Figure 3 to signal lamp.

The content is only the basic explanation under present inventive concept, and according to technical scheme made any etc. Effect conversion, all should belong to protection scope of the present invention.

Figure of description explanation

Fig. 1 intelligent Control System for Traffic Lights frame construction drawings

Signal timing dial automatic adjusting methods of the Fig. 2 corresponding to a signal period

Fig. 3 in-site installation implementing procedure figures

Fig. 4 green light utilization rates compare

The each phase place in Fig. 5 crossings come the comparison flowing vehicle and wait in line vehicle number

Embodiment

According to said method, corresponding emulation has been carried out on computers.Emulation considers the crossing containing four signal phases, It is designated as A, B, C and D respectively, flows vehicle and randomly generate by Poisson distribution, emulation has carried out 50 signal periods altogether.

Fig. 4 is that the total green light utilization rate in crossing compares, and green light utilization rate corresponds to formula（3）In.It can be seen that, using this After method, its green light utilization rate is improved.

Fig. 5 is each phase place in crossing the comparison flowing vehicle and wait in line vehicle number.As seen from the figure, this is being provided without During method（That is timing timing scheme）, the queuing vehicle of crossing B and crossing D continues to increase, and forms congestion, and A phases and C phases are then come Stream vehicle is few, and green light transit time is underutilized；After using this method, the queuing vehicle base sheet of crossing B and crossing D Without crossing A and crossing C has vehicle queue to wait once in a while, but just disappears immediately.It can be seen that, using this method after, effectively can move State recognizes that the traffic conditions at crossing, automatic regulating signal timing reduce congestion.

Cost and benefit is estimated

（One）, cost

By taking a crossing as an example, the transformation input that implementing this method needs is only to change Traffic signal control machine, with When the camera video signal at crossing is sent to traffic grade machine, overall input is can be controlled within thousands of yuans.

（Two）, benefit

Its benefit is mainly reflected in reduction of the vehicle by oil consumption during crossing（Economic benefit）, exhaust emissions minimizing （Environmental benefit）, go out the raising of line efficiency and corresponding driver's bad mental emotion reduces the traffic safety factor that brings and lifted （Social benefit）.Wherein social benefit is difficult to provide accurately assessment, only makees one slightly to economic benefit and environmental benefit here Calculating slightly.

1st, economic benefit

, from the vehicle oil consumption for saving, this is relevant with the magnitude of traffic flow at crossing for economic benefit.The magnitude of traffic flow at crossing Affected by factors such as road width, traffic time sections, as shown in table 1.12h traffic by main roads in table and secondary road Flow is added, and the 12h magnitudes of traffic flow at crossing are obtained.Consider that the magnitude of traffic flow at night is fewer than daytime a lot, take night here The magnitude of traffic flow of 12h for daytime 10%, therefore, the 24h magnitudes of traffic flow are multiplied by coefficient 1.1 by the 12h magnitudes of traffic flow and obtain, and thus may be used The mean value for being further calculated the 24h magnitudes of traffic flow is 16579, as shown in table 2.

1 intersection traffic flow standard of table

2 intersection 24h magnitude of traffic flow standards of table

After installing intelligent transportation lamp controller, if average latency of each car at crossing reduces 5 seconds, a crossing The daily magnitude of traffic flow converts into total time based on 16579, then for 82895 seconds.Oil consumption during a pick-up parking waiting is 0.8 L/h, then about 18.4 liters, every year about 6716 liters of the fuel oil that saves daily.Calculation of price with No. 93 7.94 yuan/liter of gasoline （In March, 2013 Nantong price）, 53325.04 yuan of RMB is converted into, single from terms of direct economic benefit, make up enough The improvement expenses at the crossing.

2nd, environmental benefit

The carbon emission coefficient of gasoline is 2.361kgCO₂/ L, according to result of calculation above, the saving in a year of a crossing About 6716 liters of fuel oil, the carbon emission amount of minimizing mutually should be 3.361 × 6716=22.57（Ton）If being generalized to a large-scale city City, or the whole nation, its enormous amount, environmental benefit are very notable.

Bibliography

[1] CCTV. expert claims 15 urban traffic blockings of China, 1,000,000,000 yuan of [EB/OL] .http of loss daily:// news.xinhuanet.com/fortune/2012-08/23/c_123621201.htm,2013-03-23.

[2] Wen Zhida, Liang Guirong, Chen Biming, Gao Suping. the intelligent Control System for Traffic Lights [J] based on vehicle flowrate. automatically Change technology and application, 2009,28 (6):115-118.

[3] horse great writing, Chen Songli, Chen Zhiguo, Li Jian. a kind of novel radio crossroad access lamp Intelligent Dynamic sensing control System [J] processed. Small heparin, 2009,30 (4):62-66.

[4] Zhang Wenpu. road traffic detects [M]. Beijing：People's Transportation Press, 2010.

[5] Xu Jianmin. traffic administration and control [M]. Beijing:People's Transportation Press, 2007.105-106.

[6] Environmental monitoring in Jiangsu Province net [EB/OL] .http://www.jsem.net.cn/jshjjc/InfoDetail/? InfoID=b628bcc8-62ac-483d-b88f-f6c63f838de5&CategoryNum=026007,2013-03-26.

Claims (4)

1. a kind of intelligent Control System for Traffic Lights, including monitoring camera (1), traffic lights and countdown lamp (2), its feature It is：The system also includes that intersection vehicle flux detection microprocessor (3), Traffic Signal Timing adjust automatically calculate microprocessor (4), driver module (5), Digital Image Processor (6), I/O interfaces (7)：

Monitoring camera (1) sends the video of acquisition to Digital Image Processor (6), and Digital Image Processor (6) carries out figure Result is exported to intersection vehicle flux detection microprocessor (3) after as processing, the intersection vehicle flux detects microprocessor (3) obtain information of vehicle flowrate and send Traffic Signal Timing adjust automatically to calculating microprocessor (4), the traffic through process Signal timing dial adjust automatically calculates microprocessor (4) after processing and obtaining signal timing dial result, calls I/O interfaces (7) and shows Show drive module (5), signal timing dial result is exported to traffic lights and countdown lamp (2)；

The Traffic Signal Timing adjust automatically calculates microprocessor (4) and adopts the signal timing dial for adjusting traffic lights with the following method：

A) both direction at note crossing is respectively x and y, if the signal period of traffic lights is t, containing four phase places, respectively x Direction straight trip, x directions are turned left, y directions are kept straight on, y directions are turned left, and its phase place duration is respectively t₁、t₂、t₃And t₄, then obtain formula (1)：

T=t₁+t₂+t₃+t₄(1)

B the magnitude of traffic flow number that single track averagely passes through during) setting each phase place is respectively n₁、n₂、n₃And n₄, define green light utilization rate η is the ratio of the magnitude of traffic flow that passes through of single track and long green light time, then the long green light time utilization rate of each green light phase place is respectively

$\left\{\begin{array}{c}{\mathrm{\&eta;}}_1=\frac{n_1}{t_1}\\ {\mathrm{\&eta;}}_2=\frac{n_2}{t_2}\\ {\mathrm{\&eta;}}_3=\frac{n_3}{t_3}\\ {\mathrm{\&eta;}}_4=\frac{n_4}{t_4}\end{array}\right.---\left(2\right)$

The long green light time average utilization at crossing is

$\stackrel{\&OverBar;}{\mathrm{\&eta;}}=\frac{\underset{i=1}{\overset{4}{\&Sigma;}}{n}_i}{\underset{i=1}{\overset{4}{\&Sigma;}}{t}_i}---\left(3\right)$

Generally, above-mentioned 5 utilization rates unequal, i.e.,

${\mathrm{\&eta;}}_1\&NotEqual;{\mathrm{\&eta;}}_2\&NotEqual;{\mathrm{\&eta;}}_3\&NotEqual;{\mathrm{\&eta;}}_4\&NotEqual;\stackrel{\&OverBar;}{\mathrm{\&eta;}}---\left(4\right)$

C, at the end of) remembering a signal period, during the signal period for measuring, traffic parameter is t_i, i=1,2,3,4 andThen The signal duration basic value t ' of next signal period each phase place_i, i=1,2,3,4 is

$\left\{\begin{array}{c}{t}_1^{\&prime;}=\frac{n_1}{\stackrel{\&OverBar;}{\mathrm{\&eta;}}}\\ t_2^{\&prime;}=\frac{n_2}{\stackrel{\&OverBar;}{\mathrm{\&eta;}}}\\ t_3^{\&prime;}=\frac{n_3}{\stackrel{\&OverBar;}{\mathrm{\&eta;}}}\\ t_4^{\&prime;}=\frac{n_4}{\stackrel{\&OverBar;}{\mathrm{\&eta;}}}\end{array}\right.---\left(5\right)$

t′_iAnd t_iBetween relation meet

${\mathrm{\&Sigma;t}}_i^{\&prime;}=\mathrm{\&Sigma;}\frac{n_i}{\stackrel{\&OverBar;}{\mathrm{\&eta;}}}=\frac{{\mathrm{\&Sigma;n}}_i}{\stackrel{\&OverBar;}{\mathrm{\&eta;}}}={\mathrm{\&Sigma;t}}_i---\left(6\right)$

D) according to the actual conditions at crossing, each phase place should mutually have a minimum green time, be designated as t_gmin, according to above-mentioned t '_iWith t_gminComparative result, the setting of each signal duration of next signal period considers in two kinds of situation：

(1)t′_i≥t_gmin, i=1,2,3,4

Take t '_iFor the signal duration of each phase place of next signal period, new signal period time-preserving, and each phase place is green Lamp utilization rate desired value is identical, is

(2) at least there is phase j, j ∈ { 1,2,3,4 } meet t'_j<t_gmin

Will be less than t_gminT '_iValue is adjusted to t_gmin, its time for borrowing equably shares other phase places, for this purpose, first by t ′_i, i=1,2,3,4 press ascending sequence, and new sequence is designated as s_i, according to s_iWith t_gminRelation, be adjusted correspondingly.

2. a kind of intelligent Control System for Traffic Lights as claimed in claim 1, it is characterised in that：

Intersection vehicle flux detection microprocessor (3) obtains information of vehicle flowrate using following steps：

A) identify in one signal period of traffic lights by the number of vehicles and vehicle of crossing all directions；

B) according to the length ratio of large car and compact car, equivalent kart number is converted into；

C the number is obtained the vehicle flowrate n in the per share track of the direction divided by the number of track-lines of the crossing direction)_i.

3. a kind of Intelligent traffic light control method, it is characterised in that：The method arranges a system,

The system includes that monitoring camera (1), traffic lights and countdown lamp (2), the system also include crossing wagon flow Amount detection microprocessor (3), Traffic Signal Timing adjust automatically calculate microprocessor (4), driver module (5), digitized map As processor (6), I/O interfaces (7)：

Monitoring camera (1) sends the video of acquisition to Digital Image Processor (6), and Digital Image Processor (6) carries out figure Result is exported to intersection vehicle flux detection microprocessor (3) after as processing, the intersection vehicle flux detects microprocessor (3) obtain information of vehicle flowrate and send Traffic Signal Timing adjust automatically to calculating microprocessor (4), the traffic through process Signal timing dial adjust automatically calculates microprocessor (4) after processing and obtaining signal timing dial result, calls I/O interfaces (7) and shows Show drive module (5), signal timing dial result is exported to traffic lights and countdown lamp (2)；

The Traffic Signal Timing adjust automatically calculates microprocessor (4) and adopts the signal timing dial for adjusting traffic lights with the following method：

A) both direction at note crossing is respectively x and y, if the signal period of traffic lights is t, containing four phase places, respectively x Direction straight trip, x directions are turned left, y directions are kept straight on, y directions are turned left, and its phase place duration is respectively t₁、t₂、t₃And t₄, then obtain formula (1)：

T=t₁+t₂+t₃+t₄(1)

B the magnitude of traffic flow number that single track averagely passes through during) setting each phase place is respectively n₁、n₂、n₃And n₄, define green light utilization rate η is the ratio of the magnitude of traffic flow that passes through of single track and long green light time, then the long green light time utilization rate of each green light phase place is respectively

$\left\{\begin{array}{c}{\mathrm{\&eta;}}_1=\frac{n_1}{t_1}\\ {\mathrm{\&eta;}}_2=\frac{n_2}{t_2}\\ {\mathrm{\&eta;}}_3=\frac{n_3}{t_3}\\ {\mathrm{\&eta;}}_4=\frac{n_4}{t_4}\end{array}\right.---\left(2\right)$

The long green light time average utilization at crossing is

$\stackrel{\&OverBar;}{\mathrm{\&eta;}}=\frac{\underset{i=1}{\overset{4}{\&Sigma;}}{n}_i}{\underset{i=1}{\overset{4}{\&Sigma;}}{t}_i}---\left(3\right)$

Generally, above-mentioned 5 utilization rates unequal, i.e.,

${\mathrm{\&eta;}}_1\&NotEqual;{\mathrm{\&eta;}}_2\&NotEqual;{\mathrm{\&eta;}}_3\&NotEqual;{\mathrm{\&eta;}}_4\&NotEqual;\stackrel{\&OverBar;}{\mathrm{\&eta;}}---\left(4\right)$

C, at the end of) remembering a signal period, during the signal period for measuring, traffic parameter is t_i, i=1,2,3,4 andThen The signal duration basic value t ' of next signal period each phase place_i, i=1,2,3,4 is

$\left\{\begin{array}{c}{t}_1^{\&prime;}=\frac{n_1}{\stackrel{\&OverBar;}{\mathrm{\&eta;}}}\\ t_2^{\&prime;}=\frac{n_2}{\stackrel{\&OverBar;}{\mathrm{\&eta;}}}\\ t_3^{\&prime;}=\frac{n_3}{\stackrel{\&OverBar;}{\mathrm{\&eta;}}}\\ t_4^{\&prime;}=\frac{n_4}{\stackrel{\&OverBar;}{\mathrm{\&eta;}}}\end{array}\right.---\left(5\right)$

t′_iAnd t_iBetween relation meet

${\mathrm{\&Sigma;t}}_i^{\&prime;}=\mathrm{\&Sigma;}\frac{n_i}{\stackrel{\&OverBar;}{\mathrm{\&eta;}}}=\frac{{\mathrm{\&Sigma;n}}_i}{\stackrel{\&OverBar;}{\mathrm{\&eta;}}}={\mathrm{\&Sigma;t}}_i---\left(6\right)$

D) according to the actual conditions at crossing, each phase place should mutually have a minimum green time, be designated as t_gmin, according to above-mentioned t '_iWith t_gminComparative result, the setting of each signal duration of next signal period considers in two kinds of situation：

(1)t′_i≥t_gmin, i=1,2,3,4

Take t '_iFor the signal duration of each phase place of next signal period, new signal period time-preserving, and each phase place is green Lamp utilization rate desired value is identical, is

(2) at least there is phase j, j ∈ { 1,2,3,4 } meet t'_j<t_gmin

Will be less than t_gminT '_iValue is adjusted to t_gmin, its time for borrowing equably shares other phase places, for this purpose, first by t ′_i, i=1,2,3,4 press ascending sequence, and new sequence is designated as s_i, according to s_iWith t_gminRelation, be adjusted correspondingly.

4. a kind of Intelligent traffic light control method as claimed in claim 3, it is characterised in that：

Intersection vehicle flux detection microprocessor (3) obtains information of vehicle flowrate using following steps：

A) identify in one signal period of traffic lights by the number of vehicles and vehicle of crossing all directions；

B) according to the length ratio of large car and compact car, equivalent kart number is converted into；

C the number is obtained the vehicle flowrate n in the per share track of the direction divided by the number of track-lines of the crossing direction)_i.