CN105957362A - Traffic signal control method based on image detection and multi-vehicle following constraint model - Google Patents

Abstract

For solving the problem that current intersection signal control cannot consider the queuing length and a traffic flow model at the same time so that discharging of vehicles is influenced, the invention provides a traffic signal control method based on image detection and a multi-vehicle following constraint model. The traffic signal control method has the advantages of designing a complete multi-channel image detection scheme, taking an FPGA chip as a detection and processing center for the vehicle queuing length in each direction of an intersection to complete quick acquisition and processing of images in each direction of the intersection and extraction of the vehicle queuing length and the pedestrian information in each direction of the intersection, setting a complete traffic Green Conflict constraint, establishing an optimization index function and a multi-vehicle following constraint traffic flow model, utilizing a two-step method corresponding to optimization of discharging of vehicles at the intersection and dependence on the traffic flow model time to perform optimization timing of traffic signals, completing a complete period of traffic signal control optimization design, and improving the vehicle discharging efficiency at the intersection the same time.

Description

Traffic signal control method based on image detection with many vehicle follow gallops restricted model

Technical field

The present invention relates to a kind of based on image detection and the traffic signal control method of many vehicle follow gallops restricted model, belong to Signal processing, communication technology and traffic signalization technology.

Background technology

In recent years, along with the quantity of the various vehicles is greatly increased, the facility of a lot of countries, road, traffic in the world Management system has been difficult to adapt to this development speed, urban transportation infrastructure insufficiency the most big or middle, traffic signalization Inharmonious, traffic dispersion system lack, that the friendship rule consciousness of vehicle scheduling and the confusion of management, traffic participant is thin etc. is many The reason of aspect result in urban transportation relatively jam, has caused the most again a series of society such as traffic safety, environmental pollution Can economic problems；To this end, lot of domestic and international scholar is devoted to traffic jam issue research, and attempt to optimize with public traffic in priority etc. to adjust Degree mode solves Urban Traffic Jam Based；External traffic control network, phase has been introduced in several city, Beijing, Shanghai etc. ten Prestige can alleviate urban transport problems；Owing to Urban Transport control problem is complicated, especially more than external industrially developed country It is the problems such as motor vehicles, bicycle, the interfering of pedestrian, road quality, input funds so that international many famous traffic Control system application time usually poor effect even lost efficacy；Reason is that the systems such as external SCATS and SCOOT only consider to hand over Logical not jam situation, the detection scheme supporting with control system only enters or rolls away from the vehicle flowrate of traffic intersection, thus obtain To prioritization scheme mistake usually occurs；Therefore, above measure and Utopian research work still can not be alleviated traffic congestion and ask Topic.

Traffic signalization is to utilize traffic signal, vehicle and the pedestrian that road runs is commanded and is dredged, hands over It is that traffic congestion alleviates the important component part controlled that messenger automatically controls, and is a kind of effective means of science traffic administration, Intersection annunciator is the controller of traffic signal, and it is mainly used in the Signalized control at crossing, and it both can realize control independently System, can gather again transport information in real time and be supplied to the central control machine foundation as decision-making；Existing semaphore realizes solely The vertical function controlled is the most powerful: the different needs according to each traffic intersection can be to realize Multiphase Control Traffic mode；According to The difference of different time sections traffic flow can realize multi-period control mode, and also can be according to working day and festivals or holidays Different control programs is set；Button on control panel can realize easily manual/auto, link, sense, many time Section, green conflict etc. control, and are furnished with communication interface, it is possible to achieve network remote controls, to make command centre satisfy the need easily The semaphore of mouth remotely monitors or carries out on-site supervision by portable machine, meets the requirement of area coordination control model.

Detect by traffic image, set up rational traffic flow model, be the effective of raising intersection vehicle clearance rate Approach；And existing crossroad signal control method can't consider queue length and traffic flow model simultaneously, have impact on intersection Crossing vehicle clearance efficiency.

Summary of the invention

Control can't consider queue length and traffic flow model simultaneously, affect car to solve existing crossroad signal Clearance efficiency, the present invention proposes a kind of traffic signalization based on image detection with many vehicle follow gallops restricted model Method, the method devises complete multiway images detection scheme, and using fpga chip as intersection all directions vehicle The detection of queue length and processing center, complete the Image Quick Collection to intersection all directions, image procossing, vehicle row Team leader's degree and pedestrian information are extracted；Meanwhile, it is provided with complete traffic " green conflict " to retrain, establish optimizing index function and many Vehicle follow gallop constraint traffic flow model, uses two steps that clearance optimization of vehicle in intersection is corresponding with relying on the traffic flow model time Method carries out the optimization timing of traffic signal, completes the traffic signalization optimization design of a complete cycle；Improve crossroad Mouth vehicle clearance efficiency.

The technical solution adopted for the present invention to solve the technical problems: a kind of detection based on image retrains with many vehicle follow gallops The traffic signal control method of model, its feature comprises the steps of

Step 1: traffic signal control scheme each signal period of intersection is designed once, traffic signal control scheme Design content includes multiway images infomation detection, " green conflict " constraint setting, queuing vehicle traffic flow model, signal optimization design Four partial contents；Traffic signal control scheme design time T_shejiLess than set-point, can not repeatedly adjust during signal performs Whole；T before performing the next signal cycle_shejiMoment just designs this cycle traffic signal timing plan, to ensure multichannel figure As infomation detection obtains up-to-date traffic；

Step 2: multichannel traffic video is sent into after Video decoding module digitized FPGA, first passes through limit in FPGA Edge detection and binaryzation, complete image is carried out pretreatment and be deposited into SRAM buffering, then constituting according to lane line pixel Lane detection region image is split and corrodes, extract crossing all directions queuing vehicle length and following distance, and The same area specified in adjacent two two field pictures is compared at FPGA, it is thus achieved that with or without target travel information to obtain vehicle fortune Dynamic speed；Similar method is used for detecting pedestrian's number and gait of march；The multiway images infomation detection following information of acquisition:

(1) keep straight in east orientation west: after the unlatching of the following distance of each queuing vehicle, green light, each car of queuing vehicle arrives zebra Line time, arrival crossing, opposite time；

(2) keep straight on eastwards in west: after the unlatching of the following distance of each queuing vehicle, green light, each car of queuing vehicle arrives zebra Line time, arrival crossing, opposite time；

(3) keep straight in north orientation south: after the unlatching of the following distance of each queuing vehicle, green light, each car of queuing vehicle arrives zebra Line time, arrival crossing, opposite time；

(4) keep straight in south orientation north: after the unlatching of the following distance of each queuing vehicle, green light, each car of queuing vehicle arrives zebra Line time, arrival crossing, opposite time；

(5) turn left in east orientation south: after the unlatching of the following distance of each queuing vehicle, green light, each car of queuing vehicle arrives zebra Line time, arrival South Road mouth time；

(6) northwards turn left in west: after the unlatching of the following distance of each queuing vehicle, green light, each car of queuing vehicle arrives zebra Line time, arrival North Road mouth time；

(7) turn left in north orientation east: after the unlatching of the following distance of each queuing vehicle, green light, each car of queuing vehicle arrives zebra Line time, arrival East Road mouth time；

(8) turn left in south orientation west: after the unlatching of the following distance of each queuing vehicle, green light, each car of queuing vehicle arrives zebra Line time, arrival West Road mouth time；

(9) north east is turned right: after the unlatching of the following distance of each queuing vehicle, green light, each car of queuing vehicle arrives zebra Line time, arrival North Road mouth time；

(10) west south is turned right: after the unlatching of the following distance of each queuing vehicle, green light, each car of queuing vehicle arrives zebra Line time, arrival South Road mouth time；

(11) north west is turned right: after the unlatching of the following distance of each queuing vehicle, green light, each car of queuing vehicle arrives zebra Line time, arrival West Road mouth time；

(12) south east is turned right: after the unlatching of the following distance of each queuing vehicle, green light, each car of queuing vehicle arrives zebra Line time, arrival East Road mouth time；

(13) pedestrian's east orientation west: analyze from both sides right, left respectively pedestrian after People's Bank of China green light is opened with vehicle collision, analyze people Number number and composition situation；

(14) pedestrian west is eastwards: analyze from both sides right, left respectively pedestrian after People's Bank of China green light is opened with vehicle collision, analyze people Number number and composition situation；

(15) pedestrian's south orientation north: analyze from both sides right, left respectively pedestrian after People's Bank of China green light is opened with vehicle collision, analyze people Number number and composition situation；

(16) pedestrian's north orientation south: analyze from both sides right, left respectively pedestrian after People's Bank of China green light is opened with vehicle collision, analyze people Number number and composition situation；

Step 3: green conflict constraint；

(1) for vehicle, definition subscript first letter s be vehicle from north orientation south to, n be vehicle from the south orientation north to, E is vehicle direction from West to East, w be vehicle from east orientation west to；Subscript second letter s is that vehicle is kept straight on, r is that vehicle is right Turn, l is that vehicle turns left；The 3rd alphabetical i of subscript represents green light start-up time, and f represents green light close moment；Subscript rwr is row People from right-hand side, the i.e. north, from east orientation west to passing through intersection, rwl be pedestrian from left-hand side, i.e. south, from east orientation west Intersection is passed through in direction, and rer is that pedestrian passes through intersection from right-hand side, i.e. south, from West to East direction, and rel is pedestrian From left-hand side, i.e. the north, from West to East direction pass through intersection, rnr be pedestrian from right-hand side, i.e. in the east, from the south orientation north To passing through intersection, rnl be pedestrian from left-hand side, i.e. west, from the south orientation north to passing through intersection, rsr be pedestrian from Right-hand side, i.e. west, from north orientation south to passing through intersection, rsl be pedestrian from left-hand side, i.e. in the east, from north orientation south to Pass through intersection；For pedestrian, the 4th alphabetical i of subscript represents green light start-up time, and f represents green light close moment；

(2) assuming that each direction green light opening time different, in each cycle, initial time is set to t₀, the cycle is set to T, car It is designated from craspedodrome direction, north orientation south green light signalsVehicle is green from left-hand rotation direction, north orientation south Modulating signal is designatedVehicle is designated from right-hand rotation direction, north orientation south green light signals

Vehicle is designated from craspedodrome direction, south orientation north green light signalsVehicle is from south orientation Left-hand rotation direction, north green light signals is designatedVehicle is from right-hand rotation direction, south orientation north green light signals It is designated

Vehicle craspedodrome direction green light signals from West to East is designatedVehicle westerly to Left-hand rotation direction, east green light signals is designatedVehicle right-hand rotation direction green light signals mark from West to East Knowledge is

Vehicle is designated from craspedodrome direction, east orientation west green light signalsVehicle is from east orientation Western left-hand rotation direction green light signals is designatedVehicle is from right-hand rotation direction, east orientation west green light signals It is designated

(3) pedestrian is designated to passing through intersection green light signals from east orientation west from right-hand side

Pedestrian is designated to passing through intersection green light signals from left-hand side from east orientation west

Pedestrian passes through intersection green light signals from right-hand side direction from West to East and is designated

Pedestrian from left-hand side from West to East direction pass through intersection green light signals and be designated

Pedestrian is designated to passing through intersection green light signals from the south orientation north from right-hand side

Pedestrian is designated to passing through intersection green light signals from left-hand side from the south orientation north

Pedestrian is designated to passing through intersection green light signals from north orientation south from right-hand side

Pedestrian is designated to passing through intersection green light signals from left-hand side from north orientation south

The most essential green conflict is constrained to: b_ss·b_es=0, b_ss·b_ws=0, b_ss·b_nl=0, b_ns·b_sl=0, b_es· b_wl=0, b_ws·b_el=0, b_ss·b_rwr=0, b_ss·b_rwl=0, b_ss·b_rer=0, b_ss·b_rel=0, b_ns·b_es=0, b_ns· b_ws=0；b_ns·b_rwr=0, b_ns·b_rwl=0, b_ns·b_rer=0, b_ns·b_rel=0；

(5) select the green conflict used to be constrained to:

Craspedodrome green light westwards of playing the host is turned left early than north orientation south, direction the most eastwards, during green light, After i.e. north orientation south left-hand rotation direction green light start-up time terminates more than east orientation west craspedodrome green light finish time and east orientation west craspedodrome green light Last car is turned left the time behind track by north orientation south by zebra crossingSum；

Craspedodrome green light westwards of playing the host is later than north orientation south and turns left, direction the most eastwards, during green light, I.e. east orientation west craspedodrome green light start-up time is turned left green light finish time and left-hand rotation direction, north orientation south green light knot more than north orientation south After bundle, last car is passed through the time after the western Through Lane of east orientation by zebra crossingSum；

When west, craspedodrome green light eastwards is turned left early than the south orientation north, direction the most westwards, during green light, After i.e. south orientation north left-hand rotation direction green light start-up time terminates more than west craspedodrome green light eastwards, last car is passed through south by zebra crossing North turn left the time behind trackSum；

Turn left when west craspedodrome green light eastwards is later than the south orientation north, direction the most westwards, during green light, I.e. west craspedodrome green light start-up time eastwards is turned left green light finish time and left-hand rotation direction, south orientation north green light knot more than the south orientation north After bundle, last car is by the time after zebra crossing to darcy Through Lane eastwardsSum；

When craspedodrome green light in south orientation north is turned left early than east orientation west, direction i.e. to the south, during green light, After i.e. east orientation west left-hand rotation direction green light start-up time terminates more than south orientation north craspedodrome green light finish time and south orientation north craspedodrome green light Last car is turned left the time behind track by east orientation west by zebra crossingSum；

Turn left when craspedodrome green light in south orientation north is later than east orientation west, direction i.e. to the south, during green light, I.e. craspedodrome green light start-up time in south orientation north is more than left-hand rotation direction, east orientation west green light finish time and left-hand rotation direction, east orientation west green light knot After bundle, last car is passed through the time after the Through Lane of south orientation north by zebra crossingSum；

When craspedodrome green light in north orientation south turns left eastwards early than west direction, the most northwards direction, during green light, After i.e. west left-hand rotation direction green light start-up time eastwards terminates more than north orientation south craspedodrome green light finish time and north orientation south craspedodrome green light Last car is turned left the time behind track by west east by zebra crossingSum；

Turn left eastwards direction, the most northwards direction when craspedodrome green light in north orientation south is later than west, during green light, I.e. north orientation south craspedodrome green light start-up time is turned left green light finish time and west left-hand rotation direction green light eastwards knot east more than west After bundle, last car is arrived the time after the Through Lane of north orientation south by zebra crossingSum；

When left-hand rotation green light in north orientation south is early than east orientation western right-hand lay pedestrian's green light, t_rwri>t_slf, i.e. the western right hand side of east orientation To pedestrian's green light opening time more than north orientation south left-hand rotation green light finish time；

When left-hand rotation green light in north orientation south is later than east orientation western right-hand lay pedestrian's green light,I.e. north The left-hand rotation green light opening time to the south is green more than east orientation western right-hand lay pedestrian's green light finish time right-hand lay western with east orientation pedestrian Lamp terminates rear east orientation western right-hand lay pedestrian by waiting that line passes through the time of north orientation south left-hand rotation direction laneSum；

When west left-hand rotation green light eastwards is early than east orientation western right-hand lay pedestrian's green light,I.e. east Westwards the right-hand lay pedestrian green light opening time is more than west left-hand rotation green light finish time eastwards and west after left-hand rotation green light terminates eastwards Last car is arrived the time behind track, south orientation north by zebra crossingSum；

When west left-hand rotation green light eastwards is later than east orientation western right-hand lay pedestrian's green light, t_eli>t_rwrf, i.e. west is turned left eastwards green The lamp opening time is more than east orientation western right-hand lay pedestrian's green light finish time；

When left-hand rotation green light in south orientation north is early than east orientation western left hand direction pedestrian's green light, t_rwli>t_nlf, i.e. the western left-hand of east orientation To pedestrian's green light opening time more than south orientation north left-hand rotation green light finish time；

When left-hand rotation green light in south orientation north is later than east orientation western left hand direction pedestrian's green light,I.e. south Northwards the left-hand rotation green light opening time is green more than east orientation western left hand direction pedestrian's green light finish time left hand western with east orientation direction pedestrian Lamp terminates rear east orientation western left hand direction pedestrian by waiting that line passes through the time of south orientation north left-hand rotation direction laneSum；

When playing the host that westwards left-hand rotation green light is early than east orientation western left hand direction pedestrian's green light,I.e. East orientation western left hand direction pedestrian's green light opening time terminated with east orientation west left-hand rotation green light more than east orientation west left-hand rotation green light finish time Last car rear is arrived the time behind track, north orientation south by zebra crossingSum；

When left-hand rotation green light westwards of playing the host is later than east orientation western left hand direction pedestrian's green light, t_eli>t_rwlf, i.e. west is turned left eastwards green The lamp opening time is more than east orientation western left hand direction pedestrian's green light finish time；

When left-hand rotation green light in south orientation north is early than west right-hand lay pedestrian green light eastwards, t_reri>t_nlf, i.e. west right direction eastwards Pedestrian's green light opening time is more than south orientation north left-hand rotation green light finish time；

When left-hand rotation green light in south orientation north is later than west right-hand lay pedestrian green light eastwards,I.e. south Northwards the left-hand rotation green light opening time is green more than west right-hand lay pedestrian green light finish time and west eastwards right-hand lay pedestrian eastwards After lamp end, west right-hand lay pedestrian eastwards is by waiting that line passes through the time of south orientation north left-hand rotation direction laneIt With；

When playing the host that westwards left-hand rotation green light is early than west right-hand lay pedestrian green light eastwards,I.e. The west right-hand lay pedestrian green light opening time eastwards terminated with east orientation west left-hand rotation green light more than east orientation west left-hand rotation green light finish time Last car rear is arrived the time behind track, north orientation south by zebra crossingSum；

When left-hand rotation green light westwards of playing the host is later than west right-hand lay pedestrian green light eastwards, t_eli>t_rwrf, i.e. west is turned left eastwards green The lamp opening time is more than west right-hand lay pedestrian green light finish time eastwards；

When left-hand rotation green light in north orientation south is early than west left hand direction pedestrian green light eastwards, t_reli>t_slf, i.e. west left-hand eastwards To pedestrian's green light opening time more than north orientation south left-hand rotation green light finish time；

When left-hand rotation green light in north orientation south is later than west left hand direction pedestrian green light eastwards,I.e. north The left-hand rotation green light opening time to the south is green more than west left hand direction pedestrian green light finish time and west left hand direction pedestrian eastwards eastwards Lamp terminates rear west left hand direction pedestrian eastwards by waiting that line passes through the time of north orientation south left-hand rotation direction laneSum；

When west left-hand rotation green light eastwards is early than west left hand direction pedestrian green light eastwards,I.e. west The left hand direction pedestrian green light opening time is more than west left-hand rotation green light finish time eastwards and west after left-hand rotation green light terminates eastwards eastwards Last car is arrived the time behind track, south orientation north by zebra crossingSum；

When west left-hand rotation green light eastwards is later than west left hand direction pedestrian green light eastwards, t_eli>t_relf, i.e. west is turned left eastwards green The lamp opening time is more than west left hand direction pedestrian green light finish time eastwards；

By 90-degree rotation counterclockwise for direction, crossing, i.e. north replaces original east, west to replace original north, south to replace west, east originally Replace original south, in like manner can obtain south orientation north, the green conflict constraints of north orientation south pedestrian；

Step 4: traffic flow model dynamic constrained is expressed as follows:

1. the improvement that m, front of consideration car affects with microcosmic traffic flow model of speeding is:

$\begin{array}{c}\frac{d^2{x}_n\left(t\right)}{{\mathrm{dt}}^2}=a\left\{V\[{\mathrm{\Δx}}_n\left(t\right)\]-\frac{{\mathrm{dx}}_n\left(t\right)}{dt}\right\}+{\mathrm{\λ}}_a\frac{{\mathrm{d\Δx}}_n\left(t\right)}{dt}+\\ \underset{k=1}{\overset{m}{\mathrm{\Σ}}}\left\{{\mathrm{\γ}}_{ak}\left\{V\[{\mathrm{\Δx}}_{n+k}\left(t-{\mathrm{\Δt}}_{k-1}\right)\]-V\[{\mathrm{\Δx}}_{n+k-1}\left(t-{\mathrm{\Δt}}_{k-1}\right)\]\right\}\right\}\end{array}---\left(1\right)$

Wherein, x_nT () is n-th car position of moment t,It is the speed of n-th car of moment t, △ x_nT () is Space headway between continuous print two cars, V [△ x_n(t)] it is n-th car optimal speed function, a is the sensitive system of driver Number, λ_aIt is the response parameter of relative speed difference, γ_ak>=0 is the response parameter to n-th+k-1 car optimal speed difference, △ t_k-1For The time delay that the optimal speed difference response parameter of n-th car is taken by n-th+k-1 car of n-th front side；Ginseng in model Number relation is: △ t_k-△t_k-1>0,γ_a(k-1)>γ_ak, k=1,2 ..., m；

2. willApproximate expression is:

$\left\{\begin{array}{c}\frac{{\mathrm{dx}}_n\left(t\right)}{dt}\≈\frac{x_n\left(t+T\right)-x_n\left(t-T\right)}{2T}\\ \frac{{\mathrm{d\Δx}}_n\left(t\right)}{dt}\≈\frac{{\mathrm{\Δx}}_n\left(t+T\right)-{\mathrm{\Δx}}_n\left(t-T\right)}{2T}\\ \frac{d^2{x}_n\left(t\right)}{{\mathrm{dt}}^2}\≈\frac{8\[x_n\left(t+T\right)-x_n\left(t-T\right)\]-x_n\left(t+2T\right)+x_n\left(t-2T\right)}{12T^2}\end{array}\right.---\left(2\right)$

Wherein, T is the sampling period；

Obtaining the improvement of front m car impact with microcosmic discrete traffic model of speeding is:

$\begin{array}{c}{x}_n(t+2T)=(8+6a)\[x_n(t+T)-x_n(t-T)\]-12aTV\[{\mathrm{\Δx}}_n\left(t\right)\]-6{\mathrm{\λ}}_a\[{\mathrm{\Δx}}_n(t+T)-{\mathrm{\Δx}}_n(t-T)\]\\ -12T\underset{k=1}{\overset{m}{\mathrm{\Σ}}}\left\{{\mathrm{\γ}}_{ak}\right\{V\[{\mathrm{\Δx}}_{n+k}(t-{\mathrm{\Δt}}_{k-1})\]-V\[{\mathrm{\Δx}}_{n+k-1}(t-{\mathrm{\Δt}}_{k-1})\]\left\}\right\}+x_n\left(t-2T\right)\end{array}---\left(3\right)$

And then obtain recurrence calculation formula:

$\begin{array}{c}{x}_n\[(N+2)T\]=\underset{i=2}{\overset{N}{\Σ}}\left\{\right(8+6a\left)\right\{x_n\[\left(i+1\right)T\]-x_n\[\left(i-1\right)T)\]-12{\mathrm{aTV}}_i\[{\mathrm{\Δx}}_n\left(iT\right)\]-\\ 6{\mathrm{\λ}}_a\[{\mathrm{\Δx}}_n\[\left(i+1\right)T\]-{\mathrm{\Δx}}_n\[\left(i-1\right)T)\]-\\ 12T\underset{k=1}{\overset{m}{\mathrm{\Σ}}}\left\{{\mathrm{\γ}}_{ak}\left\{V_i\[{\mathrm{\Δx}}_{n+k}\left(iT-{\mathrm{\Δt}}_{k-1}\right)\]-V_i\[{\mathrm{\Δx}}_{n+k-1}\left(iT-{\mathrm{\Δt}}_{k-1}\right)\]\right\}\right\}+x_n\[\left(i-2\right)T\]\}\end{array}---\left(4\right)$

Wherein, V_i[△x_n(iT)] being n-th car optimal speed function when t=iT, N is positive integer；

3. x is given_n(0)=0, x_n(1)=0, can be worked as according to (4) formula | x_n[(N+2)T]-L_n| < N during δ, its In, L_nBeing the distance that n-th queuing vehicle is to be travelled after green light is opened, δ is given positive number；

Empirical statistics obtains n-th queuing vehicle needs time delay t after green light is opened_dnRear just can start, so, n-th Queuing vehicle wants operating range L after green light is opened_nRequired time t_nfFor: t_nf=t_dn+NT；

Step 5: it is as follows that signal optimizes timing method:

(1) optimizing index is set up:

J=min{ λ_ewsL_ews+λ_enrL_enr+λ_eslL_esl+λ_wesL_wes+λ_wnlL_wnl+λ_wsrL_wsr+

λ_snsL_sns+λ_serL_ser+λ_swlL_swl+λ_nssL_nss+λ_nwrL_nwr+λ_nelL_nel+ρ_ewrR_ewr+

ρ_ewlR_ewl+ρ_werR_wer+ρ_welR_wel+ρ_nsrR_nsr+ρ_nslR_nsl+ρ_snrR_snr+ρ_snlR_snl}

Wherein: λ represents vehicle weight coefficient, L represents queuing vehicle length, and ρ represents pedestrian's weight coefficient, and R represents pedestrian Number, the subscript the 1st and the e of the 2nd of λ and L, s, w, n represent direction, east, south, west, north respectively, and the 1st towards the 2nd direction； 3rd s, r, l represent craspedodrome respectively, turn right and turn left；Such as L_ewsFor the vehicle queue team leader in craspedodrome direction, east orientation west, λ_ews Weight coefficient arranged by vehicle for craspedodrome direction, east orientation west；ρ and R subscript the 1st and the e of the 2nd, s, w, n represent respectively east, south, west, The north to, and the 1st towards the 2nd direction；3rd l, r represent that the left-hand side from direction of advance or right-hand side pass through people respectively Trade；

(2) crossroad signal total cycle is chosen:

T_Z=f_z(L_ews,L_wes,L_sns,L_nss)

Wherein: T_ZLet pass time union, i.e. crossroad signal total cycle for all directions vehicle and pedestrian's green light, f_z (L_ews,L_wes,L_sns,L_nss) be according to experience it has been determined that function；

Optimizing index according to step 5 (1) and the green conflict constraint of step 3, use linear programming method to determine that each is green The vehicle number that lamp unlatching, persistent period and needs are let pass；

(3) improving with vehicular traffic flow model of speeding determines the relation of clearance vehicle number and the time of clearance according to step 4, presses Need the vehicle number let pass according to all directions, each green light determining step 5 (2) is opened, the persistent period is modified, and determines Signal total cycle.

The invention has the beneficial effects as follows: devise complete multiway images detection scheme, and using fpga chip as intersection The detection of crossing all directions vehicle queue length and processing center, complete quickly to adopt the image of intersection all directions Collection, image procossing, vehicle queue length and pedestrian information are extracted；Meanwhile, it is provided with complete traffic " green conflict " to retrain, set up Optimizing index function and many vehicle follow gallops constraint traffic flow model, use intersection clearance optimization of vehicle and rely on traffic flow The two-step method that model time is corresponding carries out the optimization timing of traffic signal, completes the traffic signalization optimization of a complete cycle Design；Improve intersection vehicle clearance efficiency.

With embodiment, the present invention is elaborated below in conjunction with the accompanying drawings.

Accompanying drawing explanation

Accompanying drawing 1 is the flowage structure block diagram of the present invention；

Accompanying drawing 2 is that the image acquisition of the present invention extracts hardware block diagram with queue length.

Detailed description of the invention

Referring to the drawings 1, accompanying drawing 2.

Step 1: traffic signal control scheme each signal period of intersection is designed once, traffic signal control scheme Design content includes multiway images infomation detection, " green conflict " constraint setting, queuing vehicle traffic flow model, signal optimization design Four partial contents；Traffic signal control scheme design time T_shejiLess than set-point, can not repeatedly adjust during signal performs Whole；T before performing the next signal cycle_shejiMoment just designs this cycle traffic signal timing plan, to ensure multichannel figure As infomation detection obtains up-to-date traffic；

Step 2: each direction video acquisition unit uses 4 CCD, and it can be come in image scene collection and give A/ D converts chip and is for further processing；A/D chip uses the 7111H chip of PHILIPS company, and 7111H chip has 4 simulations logical Road, by the picture signal on acquisition time 4 tunnel, timesharing processes, and can be selected the translative mode of 7111 by programming, pass through I²C bus is programmed, and completes the initial work of 7111H, and the output format of signal is also by I²C bus is controlled, and uses The 4:2:2 form of CCIR601；So, image scene is just converted into numerical data from analog data, can pass through buffer, send Process accordingly to fpga chip；FPGA uses the EP1C12 core in the Cyclone Series FPGA of altera corp of the U.S. Sheet；This chips close degree reaches 12060 LE unit, and (each LE includes a LUT, and a trigger and interrelated logic, be chip Realize the most basic structure of logic, be also the leading indicator of FPGA comprehensive performance evaluation), it is fully able to meet image processing algorithm Needs with analyzing logic control；169 users can meet system with I/O port and realize multiple chips of image acquisition and storage Connection request；Buffer have employed FIFO device 1041V；The video data converted by A/D conversion chip is directly entered FIFO, temporarily deposits in FIFO；When FPGA needs to process it, read operation can be carried out by repeating reading instruction, Because repetitive instruction can become the instruction in more to 5 cycles the instruction in 1 cycle, so FPGA once can read greatly The data of amount, thus realize the function of buffering；Multichannel traffic video is sent into after Video decoding module digitized FPGA, FPGA first passes through rim detection and binaryzation completes image carries out pretreatment and is deposited into SRAM buffering, then according to car Image is split and corrodes by the lane detection region that diatom pixel is constituted, and extracts crossing all directions queuing vehicle length And following distance, and the same area specified in adjacent two two field pictures is compared at FPGA, it is thus achieved that with or without target travel information To obtain Velicle motion velocity；Similar method is used for detecting pedestrian's number and gait of march；Multiway images infomation detection obtains Following information:

(1) keep straight in east orientation west: after the unlatching of the following distance of each queuing vehicle, green light, each car of queuing vehicle arrives zebra Line time, arrival crossing, opposite time；

(2) keep straight on eastwards in west: after the unlatching of the following distance of each queuing vehicle, green light, each car of queuing vehicle arrives zebra Line time, arrival crossing, opposite time；

(3) keep straight in north orientation south: after the unlatching of the following distance of each queuing vehicle, green light, each car of queuing vehicle arrives zebra Line time, arrival crossing, opposite time；

(4) keep straight in south orientation north: after the unlatching of the following distance of each queuing vehicle, green light, each car of queuing vehicle arrives zebra Line time, arrival crossing, opposite time；

(5) turn left in east orientation south: after the unlatching of the following distance of each queuing vehicle, green light, each car of queuing vehicle arrives zebra Line time, arrival South Road mouth time；

(6) northwards turn left in west: after the unlatching of the following distance of each queuing vehicle, green light, each car of queuing vehicle arrives zebra Line time, arrival North Road mouth time；

(7) turn left in north orientation east: after the unlatching of the following distance of each queuing vehicle, green light, each car of queuing vehicle arrives zebra Line time, arrival East Road mouth time；

(8) turn left in south orientation west: after the unlatching of the following distance of each queuing vehicle, green light, each car of queuing vehicle arrives zebra Line time, arrival West Road mouth time；

(9) north east is turned right: after the unlatching of the following distance of each queuing vehicle, green light, each car of queuing vehicle arrives zebra Line time, arrival North Road mouth time；

(10) west south is turned right: after the unlatching of the following distance of each queuing vehicle, green light, each car of queuing vehicle arrives zebra Line time, arrival South Road mouth time；

(11) north west is turned right: after the unlatching of the following distance of each queuing vehicle, green light, each car of queuing vehicle arrives zebra Line time, arrival West Road mouth time；

(12) south east is turned right: after the unlatching of the following distance of each queuing vehicle, green light, each car of queuing vehicle arrives zebra Line time, arrival East Road mouth time；

(13) pedestrian's east orientation west: analyze from both sides right, left respectively pedestrian after People's Bank of China green light is opened with vehicle collision, analyze people Number number and composition situation；

(14) pedestrian west is eastwards: analyze from both sides right, left respectively pedestrian after People's Bank of China green light is opened with vehicle collision, analyze people Number number and composition situation；

(15) pedestrian's south orientation north: analyze from both sides right, left respectively pedestrian after People's Bank of China green light is opened with vehicle collision, analyze people Number number and composition situation；

(16) pedestrian's north orientation south: analyze from both sides right, left respectively pedestrian after People's Bank of China green light is opened with vehicle collision, analyze people Number number and composition situation；

Step 3: green conflict constraint；

(1) for vehicle, definition subscript first letter s be vehicle from north orientation south to, n be vehicle from the south orientation north to, E is vehicle direction from West to East, w be vehicle from east orientation west to；Subscript second letter s is that vehicle is kept straight on, r is that vehicle is right Turn, l is that vehicle turns left；The 3rd alphabetical i of subscript represents green light start-up time, and f represents green light close moment；Subscript rwr is row People from right-hand side, the i.e. north, from east orientation west to passing through intersection, rwl be pedestrian from left-hand side, i.e. south, from east orientation west Intersection is passed through in direction, and rer is that pedestrian passes through intersection from right-hand side, i.e. south, from West to East direction, and rel is pedestrian From left-hand side, i.e. the north, from West to East direction pass through intersection, rnr be pedestrian from right-hand side, i.e. in the east, from the south orientation north To passing through intersection, rnl be pedestrian from left-hand side, i.e. west, from the south orientation north to passing through intersection, rsr be pedestrian from Right-hand side, i.e. west, from north orientation south to passing through intersection, rsl be pedestrian from left-hand side, i.e. in the east, from north orientation south to Pass through intersection；For pedestrian, the 4th alphabetical i of subscript represents green light start-up time, and f represents green light close moment；

(2) assuming that each direction green light opening time different, in each cycle, initial time is set to t₀, the cycle is set to T, vehicle From craspedodrome direction, north orientation south, green light signals is designatedVehicle is from left-hand rotation direction, north orientation south green light signals It is designatedVehicle is designated from right-hand rotation direction, north orientation south green light signals

Vehicle is designated from craspedodrome direction, south orientation north green light signalsVehicle is from south orientation north Left-hand rotation direction green light signals is designatedVehicle identifies from right-hand rotation direction, south orientation north green light signals For

Vehicle craspedodrome direction green light signals from West to East is designatedVehicle is from West to East Left-hand rotation direction green light signals is designatedVehicle right-hand rotation direction green light signals from West to East identifies For

Vehicle is designated from craspedodrome direction, east orientation west green light signalsVehicle is from east orientation Western left-hand rotation direction green light signals is designatedVehicle is from right-hand rotation direction, east orientation west green light signals It is designated

(3) pedestrian is designated to passing through intersection green light signals from east orientation west from right-hand side

Pedestrian is designated to passing through intersection green light signals from left-hand side from east orientation west

Pedestrian passes through intersection green light signals from right-hand side direction from West to East and is designated

Pedestrian from left-hand side from West to East direction pass through intersection green light signals and be designated

Pedestrian is designated to passing through intersection green light signals from the south orientation north from right-hand side

Pedestrian is designated to passing through intersection green light signals from left-hand side from the south orientation north

Pedestrian is designated to passing through intersection green light signals from north orientation south from right-hand side

Pedestrian is designated to passing through intersection green light signals from left-hand side from north orientation south

The most essential green conflict is constrained to: b_ss·b_es=0, b_ss·b_ws=0, b_ss·b_nl=0, b_ns·b_sl=0, b_es· b_wl=0, b_ws·b_el=0, b_ss·b_rwr=0, b_ss·b_rwl=0, b_ss·b_rer=0, b_ss·b_rel=0, b_ns·b_es=0, b_ns· b_ws=0；b_ns·b_rwr=0, b_ns·b_rwl=0, b_ns·b_rer=0, b_ns·b_rel=0；

(5) select the green conflict used to be constrained to:

Craspedodrome green light westwards of playing the host is turned left early than north orientation south, direction the most eastwards, during green light, After i.e. north orientation south left-hand rotation direction green light start-up time terminates more than east orientation west craspedodrome green light finish time and east orientation west craspedodrome green light Last car is turned left the time behind track by north orientation south by zebra crossingSum；

Craspedodrome green light westwards of playing the host is later than north orientation south and turns left, direction the most eastwards, during green light, I.e. east orientation west craspedodrome green light start-up time is turned left green light finish time and left-hand rotation direction, north orientation south green light knot more than north orientation south After bundle, last car is passed through the time after the western Through Lane of east orientation by zebra crossingSum；

When west, craspedodrome green light eastwards is turned left early than the south orientation north, direction the most westwards, during green light, After i.e. south orientation north left-hand rotation direction green light start-up time terminates more than west craspedodrome green light eastwards, last car is passed through south by zebra crossing North turn left the time behind trackSum；

Turn left when west craspedodrome green light eastwards is later than the south orientation north, direction the most westwards, during green light, I.e. west craspedodrome green light start-up time eastwards is turned left green light finish time and left-hand rotation direction, south orientation north green light knot more than the south orientation north After bundle, last car is by the time after zebra crossing to darcy Through Lane eastwardsSum；

When craspedodrome green light in south orientation north is turned left early than east orientation west, direction i.e. to the south, during green light, After i.e. east orientation west left-hand rotation direction green light start-up time terminates more than south orientation north craspedodrome green light finish time and south orientation north craspedodrome green light Last car is turned left the time behind track by east orientation west by zebra crossingSum；

Turn left when craspedodrome green light in south orientation north is later than east orientation west, direction i.e. to the south, during green light, I.e. craspedodrome green light start-up time in south orientation north is more than left-hand rotation direction, east orientation west green light finish time and left-hand rotation direction, east orientation west green light knot After bundle, last car is passed through the time after the Through Lane of south orientation north by zebra crossingSum；

When craspedodrome green light in north orientation south turns left eastwards early than west direction, the most northwards direction, during green light, After i.e. west left-hand rotation direction green light start-up time eastwards terminates more than north orientation south craspedodrome green light finish time and north orientation south craspedodrome green light Last car is turned left the time behind track by west east by zebra crossingSum；

Turn left eastwards direction, the most northwards direction when craspedodrome green light in north orientation south is later than west, during green light, I.e. north orientation south craspedodrome green light start-up time is turned left green light finish time and west left-hand rotation direction green light eastwards knot east more than west After bundle, last car is arrived the time after the Through Lane of north orientation south by zebra crossingSum；

When left-hand rotation green light in north orientation south is early than east orientation western right-hand lay pedestrian's green light, t_rwri>t_slf, i.e. the western right hand side of east orientation To pedestrian's green light opening time more than north orientation south left-hand rotation green light finish time；

When left-hand rotation green light in north orientation south is later than east orientation western right-hand lay pedestrian's green light,I.e. north The left-hand rotation green light opening time to the south is green more than east orientation western right-hand lay pedestrian's green light finish time right-hand lay western with east orientation pedestrian Lamp terminates rear east orientation western right-hand lay pedestrian by waiting that line passes through the time of north orientation south left-hand rotation direction laneSum；

When west left-hand rotation green light eastwards is early than east orientation western right-hand lay pedestrian's green light,I.e. east Westwards the right-hand lay pedestrian green light opening time is more than west left-hand rotation green light finish time eastwards and west after left-hand rotation green light terminates eastwards Last car is arrived the time behind track, south orientation north by zebra crossingSum；

When west left-hand rotation green light eastwards is later than east orientation western right-hand lay pedestrian's green light, t_eli>t_rwrf, i.e. west is turned left eastwards green The lamp opening time is more than east orientation western right-hand lay pedestrian's green light finish time；

When left-hand rotation green light in south orientation north is early than east orientation western left hand direction pedestrian's green light, t_rwli>t_nlf, i.e. the western left-hand of east orientation To pedestrian's green light opening time more than south orientation north left-hand rotation green light finish time；

When left-hand rotation green light in south orientation north is later than east orientation western left hand direction pedestrian's green light,I.e. south Northwards the left-hand rotation green light opening time is green more than east orientation western left hand direction pedestrian's green light finish time left hand western with east orientation direction pedestrian Lamp terminates rear east orientation western left hand direction pedestrian by waiting that line passes through the time of south orientation north left-hand rotation direction laneSum；

When playing the host that westwards left-hand rotation green light is early than east orientation western left hand direction pedestrian's green light,I.e. east After westwards the left hand direction pedestrian green light opening time terminates more than east orientation west left-hand rotation green light finish time and east orientation west left-hand rotation green light Last car is arrived the time behind track, north orientation south by zebra crossingSum；

When left-hand rotation green light westwards of playing the host is later than east orientation western left hand direction pedestrian's green light, t_eli>t_rwlf, i.e. west is turned left eastwards green The lamp opening time is more than east orientation western left hand direction pedestrian's green light finish time；

When left-hand rotation green light in south orientation north is early than west right-hand lay pedestrian green light eastwards, t_reri>t_nlf, i.e. west right direction eastwards Pedestrian's green light opening time is more than south orientation north left-hand rotation green light finish time；

When left-hand rotation green light in south orientation north is later than west right-hand lay pedestrian green light eastwards,I.e. south Northwards the left-hand rotation green light opening time is green more than west right-hand lay pedestrian green light finish time and west eastwards right-hand lay pedestrian eastwards After lamp end, west right-hand lay pedestrian eastwards is by waiting that line passes through the time of south orientation north left-hand rotation direction laneIt With；

When playing the host that westwards left-hand rotation green light is early than west right-hand lay pedestrian green light eastwards,I.e. The west right-hand lay pedestrian green light opening time eastwards terminated with east orientation west left-hand rotation green light more than east orientation west left-hand rotation green light finish time Last car rear is arrived the time behind track, north orientation south by zebra crossingSum；

When left-hand rotation green light westwards of playing the host is later than west right-hand lay pedestrian green light eastwards, t_eli>t_rwrf, i.e. west is turned left eastwards green The lamp opening time is more than west right-hand lay pedestrian green light finish time eastwards；

When left-hand rotation green light in north orientation south is early than west left hand direction pedestrian green light eastwards, t_reli>t_slf, i.e. west left-hand eastwards To pedestrian's green light opening time more than north orientation south left-hand rotation green light finish time；

When left-hand rotation green light in north orientation south is later than west left hand direction pedestrian green light eastwards,I.e. north The left-hand rotation green light opening time to the south is green more than west left hand direction pedestrian green light finish time and west left hand direction pedestrian eastwards eastwards Lamp terminates rear west left hand direction pedestrian eastwards by waiting that line passes through the time of north orientation south left-hand rotation direction laneSum；

When west left-hand rotation green light eastwards is early than west left hand direction pedestrian green light eastwards,I.e. west The left hand direction pedestrian green light opening time is more than west left-hand rotation green light finish time eastwards and west after left-hand rotation green light terminates eastwards eastwards Last car is arrived the time behind track, south orientation north by zebra crossingSum；

When west left-hand rotation green light eastwards is later than west left hand direction pedestrian green light eastwards, t_eli>t_relf, i.e. west is turned left eastwards green The lamp opening time is more than west left hand direction pedestrian green light finish time eastwards；

By 90-degree rotation counterclockwise for direction, crossing, i.e. north replaces original east, west to replace original north, south to replace west, east originally Replace original south, in like manner can obtain south orientation north, the green conflict constraints of north orientation south pedestrian；

Step 4: traffic flow model dynamic constrained is expressed as follows:

1. the improvement that m, front of consideration car affects with microcosmic traffic flow model of speeding is:

$\begin{array}{c}\frac{d^2{x}_n\left(t\right)}{{\mathrm{dt}}^2}=a\left\{V\&lsqb;{\mathrm{\&Delta;x}}_n\left(t\right)\&rsqb;-\frac{{\mathrm{dx}}_n\left(t\right)}{dt}\right\}+{\mathrm{\&lambda;}}_a\frac{{\mathrm{d\&Delta;x}}_n\left(t\right)}{dt}+\\ \underset{k=1}{\overset{m}{\mathrm{\&Sigma;}}}\left\{{\mathrm{\&gamma;}}_{ak}\left\{V\&lsqb;{\mathrm{\&Delta;x}}_{n+k}\left(t-{\mathrm{\&Delta;t}}_{k-1}\right)\&rsqb;-V\&lsqb;{\mathrm{\&Delta;x}}_{n+k-1}\left(t-{\mathrm{\&Delta;t}}_{k-1}\right)\&rsqb;\right\}\right\}\end{array}---\left(1\right)$

Wherein, x_nT () is n-th car position of moment t,It is the speed of n-th car of moment t, △ x_nT () is Space headway between continuous print two cars, V [△ x_n(t)] it is n-th car optimal speed function, a is the sensitive system of driver Number, λ_aIt is the response parameter of relative speed difference, γ_ak>=0 is the response parameter to n-th+k-1 car optimal speed difference, △ t_k-1For The time delay that the optimal speed difference response parameter of n-th car is taken by n-th+k-1 car of n-th front side；Ginseng in model Number relation is: △ t_k-△t_k-1>0,γ_a(k-1)>γ_ak, k=1,2 ..., m；

2. willApproximate expression is:

$\left\{\begin{array}{c}\frac{{\mathrm{dx}}_n\left(t\right)}{dt}\&ap;\frac{x_n\left(t+T\right)-x_n\left(t-T\right)}{2T}\\ \frac{{\mathrm{d\&Delta;x}}_n\left(t\right)}{dt}\&ap;\frac{{\mathrm{\&Delta;x}}_n\left(t+T\right)-{\mathrm{\&Delta;x}}_n\left(t-T\right)}{2T}\\ \frac{d^2{x}_n\left(t\right)}{{\mathrm{dt}}^2}\&ap;\frac{8\&lsqb;x_n\left(t+T\right)-x_n\left(t-T\right)\&rsqb;-x_n\left(t+2T\right)+x_n\left(t-2T\right)}{12T^2}\end{array}\right.---\left(2\right)$

Wherein, T is the sampling period；

Obtaining the improvement of front m car impact with microcosmic discrete traffic model of speeding is:

$\begin{array}{c}{x}_n(t+2T)=(8+6a)\&lsqb;x_n(t+T)-x_n(t-T)\&rsqb;-12aTV\&lsqb;{\mathrm{\&Delta;x}}_n\left(t\right)\&rsqb;-6{\mathrm{\&lambda;}}_a\&lsqb;{\mathrm{\&Delta;x}}_n(t+T)-{\mathrm{\&Delta;x}}_n(t-T)\&rsqb;\\ -12T\underset{k=1}{\overset{m}{\mathrm{\&Sigma;}}}\left\{{\mathrm{\&gamma;}}_{ak}\right\{V\&lsqb;{\mathrm{\&Delta;x}}_{n+k}(t-{\mathrm{\&Delta;t}}_{k-1})\&rsqb;-V\&lsqb;{\mathrm{\&Delta;x}}_{n+k-1}(t-{\mathrm{\&Delta;t}}_{k-1})\&rsqb;\left\}\right\}+x_n\left(t-2T\right)\end{array}---\left(3\right)$

And then obtain recurrence calculation formula:

$\begin{array}{c}{x}_n\&lsqb;(N+2)T\&rsqb;=\underset{i=2}{\overset{N}{\&Sigma;}}\left\{\right(8+6a\left)\right\{x_n\&lsqb;\left(i+1\right)T\&rsqb;-x_n\&lsqb;\left(i-1\right)T)\&rsqb;-12{\mathrm{aTV}}_i\&lsqb;{\mathrm{\&Delta;x}}_n\left(iT\right)\&rsqb;-\\ 6{\mathrm{\&lambda;}}_a\&lsqb;{\mathrm{\&Delta;x}}_n\&lsqb;\left(i+1\right)T\&rsqb;-{\mathrm{\&Delta;x}}_n\&lsqb;\left(i-1\right)T)\&rsqb;-\\ 12T\underset{k=1}{\overset{m}{\mathrm{\&Sigma;}}}\left\{{\mathrm{\&gamma;}}_{ak}\left\{V_i\&lsqb;{\mathrm{\&Delta;x}}_{n+k}\left(iT-{\mathrm{\&Delta;t}}_{k-1}\right)\&rsqb;-V_i\&lsqb;{\mathrm{\&Delta;x}}_{n+k-1}\left(iT-{\mathrm{\&Delta;t}}_{k-1}\right)\&rsqb;\right\}\right\}+x_n\&lsqb;\left(i-2\right)T\&rsqb;\}\end{array}---\left(4\right)$

Wherein, V_i[△x_n(iT)] being n-th car optimal speed function when t=iT, N is positive integer；

3. x is given_n(0)=0, x_n(1)=0, can be worked as according to (4) formula | x_n[(N+2)T]-L_n| < N during δ, its In, L_nBeing the distance that n-th queuing vehicle is to be travelled after green light is opened, δ is given positive number；

Empirical statistics obtains n-th queuing vehicle needs time delay t after green light is opened_dnRear just can start, so, n-th Queuing vehicle wants operating range L after green light is opened_nRequired time t_nfFor: t_nf=t_dn+NT；

Step 5: it is as follows that signal optimizes timing method:

(1) optimizing index is set up:

J=min{ λ_ewsL_ews+λ_enrL_enr+λ_eslL_esl+λ_wesL_wes+λ_wnlL_wnl+λ_wsrL_wsr+

λ_snsL_sns+λ_serL_ser+λ_swlL_swl+λ_nssL_nss+λ_nwrL_nwr+λ_nelL_nel+ρ_ewrR_ewr+

ρ_ewlR_ewl+ρ_werR_wer+ρ_welR_wel+ρ_nsrR_nsr+ρ_nslR_nsl+ρ_snrR_snr+ρ_snlR_snl}

Wherein: λ represents vehicle weight coefficient, L represents queuing vehicle length, and ρ represents pedestrian's weight coefficient, and R represents pedestrian Number, the subscript the 1st and the e of the 2nd of λ and L, s, w, n represent direction, east, south, west, north respectively, and the 1st towards the 2nd direction； 3rd s, r, l represent craspedodrome respectively, turn right and turn left；Such as L_ewsFor the vehicle queue team leader in craspedodrome direction, east orientation west, λ_ews Weight coefficient arranged by vehicle for craspedodrome direction, east orientation west；ρ and R subscript the 1st and the e of the 2nd, s, w, n represent respectively east, south, west, The north to, and the 1st towards the 2nd direction；3rd l, r represent that the left-hand side from direction of advance or right-hand side pass through people respectively Trade；

(2) crossroad signal total cycle is chosen:

T_Z=f_z(L_ews,L_wes,L_sns,L_nss)

Wherein: T_ZLet pass time union, i.e. crossroad signal total cycle for all directions vehicle and pedestrian's green light, f_z (L_ews,L_wes,L_sns,L_nss) be according to experience it has been determined that function；

Optimizing index according to step 5 (1) and the green conflict constraint of step 3, use linear programming method to determine that each is green The vehicle number that lamp unlatching, persistent period and needs are let pass；

(3) improving with vehicular traffic flow model of speeding determines the relation of clearance vehicle number and the time of clearance according to step 4, presses Need the vehicle number let pass according to all directions, each green light determining step 5 (2) is opened, the persistent period is modified, and determines Signal total cycle.

Claims (1)

1. a traffic signal control method based on image detection with many vehicle follow gallops restricted model, its feature comprises following step Rapid:

Step 1: traffic signal control scheme each signal period of intersection is designed once, traffic signal control scheme designs Content includes that multiway images infomation detection, " green conflict " constraint setting, queuing vehicle traffic flow model, signal optimization design four Divide content；Traffic signal control scheme design time T_shejiLess than set-point, can not repeatedly adjust during signal performs；? Perform T before the next signal cycle_shejiMoment just designs this cycle traffic signal timing plan, to ensure multiway images information Detection obtains up-to-date traffic；

Step 2: multichannel traffic video is sent into after Video decoding module digitized FPGA, first passes through edge inspection in FPGA Survey and binaryzation, complete image is carried out pretreatment and be deposited into SRAM buffering, the car then constituted according to lane line pixel Image is split and corrodes by detection region, road, extracts crossing all directions queuing vehicle length and following distance, and by phase The same area specified in adjacent two two field pictures compares at FPGA, it is thus achieved that with or without target travel information to obtain vehicle motion speed Degree；Similar method is used for detecting pedestrian's number and gait of march；The multiway images infomation detection following information of acquisition:

(1) keep straight in east orientation west: when after the unlatching of the following distance of each queuing vehicle, green light, each car of queuing vehicle arrives zebra crossing Between, arrive crossing, the opposite time；

(2) keep straight on eastwards in west: when after the unlatching of the following distance of each queuing vehicle, green light, each car of queuing vehicle arrives zebra crossing Between, arrive crossing, the opposite time；

(3) keep straight in north orientation south: when after the unlatching of the following distance of each queuing vehicle, green light, each car of queuing vehicle arrives zebra crossing Between, arrive crossing, the opposite time；

(4) keep straight in south orientation north: when after the unlatching of the following distance of each queuing vehicle, green light, each car of queuing vehicle arrives zebra crossing Between, arrive crossing, the opposite time；

(5) turn left in east orientation south: when after the unlatching of the following distance of each queuing vehicle, green light, each car of queuing vehicle arrives zebra crossing Between, arrive the South Road mouth time；

(6) northwards turn left in west: when after the unlatching of the following distance of each queuing vehicle, green light, each car of queuing vehicle arrives zebra crossing Between, arrive the North Road mouth time；

(7) turn left in north orientation east: when after the unlatching of the following distance of each queuing vehicle, green light, each car of queuing vehicle arrives zebra crossing Between, arrive the East Road mouth time；

(8) turn left in south orientation west: when after the unlatching of the following distance of each queuing vehicle, green light, each car of queuing vehicle arrives zebra crossing Between, arrive the West Road mouth time；

(9) north east is turned right: when after the unlatching of the following distance of each queuing vehicle, green light, each car of queuing vehicle arrives zebra crossing Between, arrive the North Road mouth time；

(10) west south is turned right: when after the unlatching of the following distance of each queuing vehicle, green light, each car of queuing vehicle arrives zebra crossing Between, arrive the South Road mouth time；

(11) north west is turned right: when after the unlatching of the following distance of each queuing vehicle, green light, each car of queuing vehicle arrives zebra crossing Between, arrive the West Road mouth time；

(12) south east is turned right: when after the unlatching of the following distance of each queuing vehicle, green light, each car of queuing vehicle arrives zebra crossing Between, arrive the East Road mouth time；

(13) pedestrian's east orientation west: analyze from both sides right, left respectively pedestrian after People's Bank of China green light is opened with vehicle collision, analyze number many Widow and composition situation；

(14) pedestrian west is eastwards: analyze from both sides right, left respectively pedestrian after People's Bank of China green light is opened with vehicle collision, analyze number many Widow and composition situation；

(15) pedestrian's south orientation north: analyze from both sides right, left respectively pedestrian after People's Bank of China green light is opened with vehicle collision, analyze number many Widow and composition situation；

(16) pedestrian's north orientation south: analyze from both sides right, left respectively pedestrian after People's Bank of China green light is opened with vehicle collision, analyze number many Widow and composition situation；

Step 3: green conflict constraint；

(1) for vehicle, definition subscript first letter s be vehicle from north orientation south to, n be vehicle from the south orientation north to, e is Vehicle direction from West to East, w be vehicle from east orientation west to；Subscript second letter s is that vehicle is kept straight on, r is vehicle right-hand rotation, l It is that vehicle turns left；The 3rd alphabetical i of subscript represents green light start-up time, and f represents green light close moment；Subscript rwr be pedestrian from Right-hand side, the i.e. north, from east orientation west to passing through intersection, rwl be pedestrian from left-hand side, i.e. south, from east orientation west to Passing through intersection, rer is that pedestrian passes through intersection from right-hand side, i.e. south, from West to East direction, and rel is that pedestrian is from a left side On hand, i.e. the north, from West to East direction pass through intersection, rnr is pedestrian from right-hand side, i.e. in the east, from the south orientation north to wearing More intersection, rnl be pedestrian from left-hand side, i.e. west, from the south orientation north to passing through intersection, rsr is that pedestrian is from the right hand Limit, i.e. west, from north orientation south to passing through intersection, rsl is that pedestrian is from left-hand side, i.e. in the east, from north orientation south to passing through Intersection；For pedestrian, the 4th alphabetical i of subscript represents green light start-up time, and f represents green light close moment；

(2) assuming that each direction green light opening time different, in each cycle, initial time is set to t₀, the cycle is set to T, and vehicle is from north orientation south Craspedodrome direction green light signals is designatedVehicle is designated from left-hand rotation direction, north orientation south green light signalsVehicle is designated from right-hand rotation direction, north orientation south green light signals

Vehicle is designated from craspedodrome direction, south orientation north green light signalsVehicle is left from south orientation north Turn direction green light signals to be designatedVehicle is designated from right-hand rotation direction, south orientation north green light signals

Vehicle craspedodrome direction green light signals from West to East is designatedVehicle is the most left Turn direction green light signals to be designatedVehicle right-hand rotation direction green light signals from West to East is designated

Vehicle is designated from craspedodrome direction, east orientation west green light signalsVehicle is from east orientation west Left-hand rotation direction green light signals is designatedVehicle is from right-hand rotation direction, east orientation west green light signals It is designated

(3) pedestrian is designated to passing through intersection green light signals from east orientation west from right-hand side

Pedestrian is designated to passing through intersection green light signals from left-hand side from east orientation west

Pedestrian passes through intersection green light signals from right-hand side direction from West to East and is designated

Pedestrian from left-hand side from West to East direction pass through intersection green light signals and be designated

Pedestrian is designated to passing through intersection green light signals from the south orientation north from right-hand side

Pedestrian is designated to passing through intersection green light signals from left-hand side from the south orientation north

Pedestrian is designated to passing through intersection green light signals from north orientation south from right-hand side

Pedestrian is designated to passing through intersection green light signals from left-hand side from north orientation south

The most essential green conflict is constrained to: b_ss·b_es=0, b_ss·b_ws=0, b_ss·b_nl=0, b_ns·b_sl=0, b_es·b_wl= 0, b_ws·b_el=0, b_ss·b_rwr=0, b_ss·b_rwl=0, b_ss·b_rer=0, b_ss·b_rel=0, b_ns·b_es=0, b_ns·b_ws= 0；b_ns·b_rwr=0, b_ns·b_rwl=0, b_ns·b_rer=0, b_ns·b_rel=0；

(5) select the green conflict used to be constrained to:

Craspedodrome green light westwards of playing the host is turned left early than north orientation south, direction the most eastwards, during green light,I.e. Left-hand rotation direction, north orientation south green light start-up time terminate more than east orientation west craspedodrome green light finish time and east orientation west craspedodrome green light after A rear car is turned left the time behind track by north orientation south by zebra crossingSum；

Craspedodrome green light westwards of playing the host is later than north orientation south and turns left, direction the most eastwards, during green light,I.e. Craspedodrome green light start-up time in east orientation west terminated with left-hand rotation direction, north orientation south green light more than north orientation south green light finish time of turning left Last car rear is passed through the time after the western Through Lane of east orientation by zebra crossingSum；

When west, craspedodrome green light eastwards is turned left early than the south orientation north, direction the most westwards, during green light,I.e. After left-hand rotation direction, south orientation north green light start-up time terminates more than west craspedodrome green light eastwards, last car is passed through south orientation by zebra crossing Turn left the time behind track in the northSum；

Turn left when west craspedodrome green light eastwards is later than the south orientation north, direction the most westwards, during green light,I.e. West craspedodrome green light start-up time eastwards terminated with left-hand rotation direction, south orientation north green light more than south orientation north green light finish time of turning left Last car rear is by the time after zebra crossing to darcy Through Lane eastwardsSum；

When craspedodrome green light in south orientation north is turned left early than east orientation west, direction i.e. to the south, during green light, After i.e. east orientation west left-hand rotation direction green light start-up time terminates more than south orientation north craspedodrome green light finish time and south orientation north craspedodrome green light Last car is turned left the time behind track by east orientation west by zebra crossingSum；

Turn left when craspedodrome green light in south orientation north is later than east orientation west, direction i.e. to the south, during green light,I.e. Craspedodrome green light start-up time in south orientation north terminated with left-hand rotation direction, east orientation west green light more than left-hand rotation direction, east orientation west green light finish time Last car rear is passed through the time after the Through Lane of south orientation north by zebra crossingSum；

When craspedodrome green light in north orientation south turns left eastwards early than west direction, the most northwards direction, during green light,I.e. West left-hand rotation direction green light start-up time eastwards terminate more than north orientation south craspedodrome green light finish time and north orientation south craspedodrome green light after A rear car is turned left the time behind track by west east by zebra crossingSum；

Turn left eastwards direction, the most northwards direction when craspedodrome green light in north orientation south is later than west, during green light,I.e. Craspedodrome green light start-up time in north orientation south terminated with west left-hand rotation direction green light eastwards more than west green light finish time of turning left east Last car rear is arrived the time after the Through Lane of north orientation south by zebra crossingSum；

When left-hand rotation green light in north orientation south is early than east orientation western right-hand lay pedestrian's green light, t_rwri>t_slf, i.e. east orientation western right-hand lay pedestrian The green light opening time is more than north orientation south left-hand rotation green light finish time；

When left-hand rotation green light in north orientation south is later than east orientation western right-hand lay pedestrian's green light,I.e. north orientation south The left-hand rotation green light opening time tied with east orientation western right-hand lay pedestrian's green light more than east orientation western right-hand lay pedestrian's green light finish time After bundle, east orientation western right-hand lay pedestrian is by waiting that line passes through the time of north orientation south left-hand rotation direction laneSum；

When west left-hand rotation green light eastwards is early than east orientation western right-hand lay pedestrian's green light,I.e. east orientation west Right-hand lay pedestrian's green light opening time terminates rear last more than west left-hand rotation green light finish time eastwards and west left-hand rotation green light eastwards One car is arrived the time behind track, south orientation north by zebra crossingSum；

When west left-hand rotation green light eastwards is later than east orientation western right-hand lay pedestrian's green light, t_eli>t_rwrf, i.e. west left-hand rotation green light eastwards is opened Time is more than east orientation western right-hand lay pedestrian's green light finish time；

When left-hand rotation green light in south orientation north is early than east orientation western left hand direction pedestrian's green light, t_rwli>t_nlf, i.e. east orientation western left hand direction pedestrian The green light opening time is more than south orientation north left-hand rotation green light finish time；

When left-hand rotation green light in south orientation north is later than east orientation western left hand direction pedestrian's green light,I.e. south orientation north The left-hand rotation green light opening time is more than east orientation western left hand direction pedestrian's green light finish time and east orientation western left hand direction pedestrian's green light knot After bundle, east orientation western left hand direction pedestrian is by waiting that line passes through the time of south orientation north left-hand rotation direction laneSum；

When playing the host that westwards left-hand rotation green light is early than east orientation western left hand direction pedestrian's green light,I.e. east orientation west The left hand direction pedestrian green light opening time terminates rear last more than east orientation west left-hand rotation green light finish time and east orientation west left-hand rotation green light One car is arrived the time behind track, north orientation south by zebra crossingSum；

When left-hand rotation green light westwards of playing the host is later than east orientation western left hand direction pedestrian's green light, t_eli>t_rwlf, i.e. west left-hand rotation green light eastwards is opened Time is more than east orientation western left hand direction pedestrian's green light finish time；

When left-hand rotation green light in south orientation north is early than west right-hand lay pedestrian green light eastwards, t_reri>t_nlf, i.e. west right direction pedestrian eastwards is green The lamp opening time is more than south orientation north left-hand rotation green light finish time；

When left-hand rotation green light in south orientation north is later than west right-hand lay pedestrian green light eastwards,I.e. south orientation north The left-hand rotation green light opening time is more than west right-hand lay pedestrian green light finish time eastwards and west right-hand lay pedestrian green light eastwards knot Binding Shu Houxi right-hand lay pedestrian eastwards is by waiting that line passes through the time of south orientation north left-hand rotation direction laneSum；

When playing the host that westwards left-hand rotation green light is early than west right-hand lay pedestrian green light eastwards,I.e. west to East right-hand lay pedestrian's green light opening time terminate more than east orientation west left-hand rotation green light finish time and east orientation west left-hand rotation green light after A rear car is arrived the time behind track, north orientation south by zebra crossingSum；

When left-hand rotation green light westwards of playing the host is later than west right-hand lay pedestrian green light eastwards, t_eli>t_rwrf, i.e. west left-hand rotation green light eastwards is opened Time is more than west right-hand lay pedestrian green light finish time eastwards；

When left-hand rotation green light in north orientation south is early than west left hand direction pedestrian green light eastwards, t_reli>t_slf, i.e. west left hand direction pedestrian eastwards The green light opening time is more than north orientation south left-hand rotation green light finish time；

When left-hand rotation green light in north orientation south is later than west left hand direction pedestrian green light eastwards,I.e. north orientation south is left Turning the green light opening time terminates more than west left hand direction pedestrian green light finish time and west eastwards left hand direction pedestrian's green light eastwards Rear west left hand direction pedestrian eastwards is by waiting that line passes through the time of north orientation south left-hand rotation direction laneSum；

When west left-hand rotation green light eastwards is early than west left hand direction pedestrian green light eastwards,I.e. west is the most left The hands direction pedestrian green light opening time terminate more than west left-hand rotation green light finish time eastwards and west left-hand rotation green light eastwards after last Car is arrived the time behind track, south orientation north by zebra crossingSum；

When west left-hand rotation green light eastwards is later than west left hand direction pedestrian green light eastwards, t_eli>t_relf, i.e. west left-hand rotation green light eastwards is opened Time is more than west left hand direction pedestrian green light finish time eastwards；

By 90-degree rotation counterclockwise for direction, crossing, i.e. north replaces original east, west to replace original north, south to replace original west, east to replace Originally south, in like manner can obtain south orientation north, the green conflict constraints of north orientation south pedestrian；

Step 4: traffic flow model dynamic constrained is expressed as follows:

1. the improvement that m, front of consideration car affects with microcosmic traffic flow model of speeding is:

$\begin{array}{c}\frac{d^2{x}_n\left(t\right)}{{\mathrm{dt}}^2}=a\left\{V\&lsqb;{\mathrm{\&Delta;x}}_n\left(t\right)\&rsqb;-\frac{{\mathrm{dx}}_n\left(t\right)}{dt}\right\}+{\mathrm{\&lambda;}}_a\frac{{\mathrm{d\&Delta;x}}_n\left(t\right)}{dt}+\\ \underset{k=1}{\overset{m}{\mathrm{\&Sigma;}}}\left\{{\mathrm{\&gamma;}}_{ak}\left\{V\&lsqb;{\mathrm{\&Delta;x}}_{n+k}\left(t-{\mathrm{\&Delta;t}}_{k-1}\right)\&rsqb;-V\&lsqb;{\mathrm{\&Delta;x}}_{n+k-1}\left(t-{\mathrm{\&Delta;t}}_{k-1}\right)\&rsqb;\right\}\right\}\end{array}---\left(1\right)$

Wherein, x_nT () is n-th car position of moment t,It is the speed of n-th car of moment t, Δ x_nT () is continuous print Space headway between two cars, V [Δ x_n(t)] it is n-th car optimal speed function, a is the sensitivity coefficient of driver, λ_aIt is The response parameter of relative speed difference, γ_ak>=0 is the response parameter to n-th+k-1 car optimal speed difference, Δ t_k-1It is n-th car The time delay that the optimal speed difference response parameter of n-th car is taken by n-th+k-1, front car；Parameters relationship in model For: Δ t_k-Δt_k-1>0,γ_a(k-1)>γ_ak, k=1,2 ..., m；

2. willApproximate expression is:

$\left\{\begin{array}{c}\frac{{\mathrm{dx}}_n\left(t\right)}{dt}\&ap;\frac{x_n\left(t+T\right)-x_n\left(t-T\right)}{2T}\\ \frac{{\mathrm{d\&Delta;x}}_n\left(t\right)}{dt}\&ap;\frac{{\mathrm{\&Delta;x}}_n\left(t+T\right)-{\mathrm{\&Delta;x}}_n\left(t-T\right)}{2T}\\ \frac{d^2{x}_n\left(t\right)}{{\mathrm{dt}}^2}\&ap;\frac{8\&lsqb;x_n\left(t+T\right)-x_n\left(t-T\right)\&rsqb;-x_n\left(t+2T\right)+x_n\left(t-2T\right)}{12T^2}\end{array}\right.---\left(2\right)$

Wherein, T is the sampling period；

Obtaining the improvement of front m car impact with microcosmic discrete traffic model of speeding is:

$\begin{array}{c}{x}_n(t+2T)=(8+6a)\&lsqb;x_n(t+T)-x_n(t-T)\&rsqb;-12aTV\&lsqb;{\mathrm{\&Delta;x}}_n\left(t\right)\&rsqb;-6{\mathrm{\&lambda;}}_a\&lsqb;{\mathrm{\&Delta;x}}_n(t+T)-{\mathrm{\&Delta;x}}_n(t-T)\&rsqb;\\ -12T\underset{k=1}{\overset{m}{\mathrm{\&Sigma;}}}\left\{{\mathrm{\&gamma;}}_{ak}\right\{V\&lsqb;{\mathrm{\&Delta;x}}_{n+k}(t-{\mathrm{\&Delta;t}}_{k-1})\&rsqb;-V\&lsqb;{\mathrm{\&Delta;x}}_{n+k-1}(t-{\mathrm{\&Delta;t}}_{k-1})\&rsqb;\left\}\right\}+x_n\left(t-2T\right)\end{array}---\left(3\right)$

And then obtain recurrence calculation formula:

$\begin{array}{c}{x}_n\&lsqb;(N+2)T\&rsqb;=\underset{i=2}{\overset{N}{\&Sigma;}}\left\{\right(8+6a\left)\right\{x_n\&lsqb;\left(i+1\right)T\&rsqb;-x_n\&lsqb;\left(i-1\right)T)\&rsqb;-12{\mathrm{aTV}}_i\&lsqb;{\mathrm{\&Delta;x}}_n\left(iT\right)\&rsqb;-\\ 6{\mathrm{\&lambda;}}_a\&lsqb;{\mathrm{\&Delta;x}}_n\&lsqb;\left(i+1\right)T\&rsqb;-{\mathrm{\&Delta;x}}_n\&lsqb;\left(i-1\right)T)\&rsqb;-\\ 12T\underset{k=1}{\overset{m}{\mathrm{\&Sigma;}}}\left\{{\mathrm{\&gamma;}}_{ak}\left\{V_i\&lsqb;{\mathrm{\&Delta;x}}_{n+k}\left(iT-{\mathrm{\&Delta;t}}_{k-1}\right)\&rsqb;-V_i\&lsqb;{\mathrm{\&Delta;x}}_{n+k-1}\left(iT-{\mathrm{\&Delta;t}}_{k-1}\right)\&rsqb;\right\}\right\}+x_n\&lsqb;\left(i-2\right)T\&rsqb;\}\end{array}---\left(4\right)$

Wherein, V_i[Δx_n(iT)] being n-th car optimal speed function when t=iT, N is positive integer；

3. x is given_n(0)=0, x_n(1)=0, can be worked as according to (4) formula | x_n[(N+2)T]-L_n| < N during δ, wherein, L_nFor The distance that n-th queuing vehicle is to be travelled after green light is opened, δ is given positive number；

Empirical statistics obtains n-th queuing vehicle needs time delay t after green light is opened_dnRear just can start, so, n-th queuing Vehicle wants operating range L after green light is opened_nRequired time t_nfFor: t_nf=t_dn+NT；

Step 5: it is as follows that signal optimizes timing method:

(1) optimizing index is set up:

J=min{ λ_ewsL_ews+λ_enrL_enr+λ_eslL_esl+λ_wesL_wes+λ_wnlL_wnl+λ_wsrL_wsr+

λ_snsL_sns+λ_serL_ser+λ_swlL_swl+λ_nssL_nss+λ_nwrL_nwr+λ_nelL_nel+ρ_ewrR_ewr+

ρ_ewlR_ewl+ρ_werR_wer+ρ_welR_wel+ρ_nsrR_nsr+ρ_nslR_nsl+ρ_snrR_snr+ρ_snlR_snl}

Wherein: λ represents vehicle weight coefficient, L represents queuing vehicle length, and ρ represents pedestrian's weight coefficient, and R represents pedestrian's number, λ With the subscript the 1st and the e of the 2nd of L, s, w, n represent direction, east, south, west, north respectively, and the 1st towards the 2nd direction；3rd Position s, r, l represent craspedodrome respectively, turn right and turn left；Such as L_ewsFor the vehicle queue team leader in craspedodrome direction, east orientation west, λ_ewsFor east Westwards keep straight on direction vehicle row weight coefficient；ρ and R subscript the 1st and the e of the 2nd, s, w, n represent east, south, west, north side respectively To, and the 1st towards the 2nd direction；3rd l, r represent that the left-hand side from direction of advance or right-hand side pass through People's Bank of China respectively Road；

(2) crossroad signal total cycle is chosen:

T_Z=f_z(L_ews,L_wes,L_sns,L_nss)

Wherein: T_ZLet pass time union, i.e. crossroad signal total cycle for all directions vehicle and pedestrian's green light, f_z(L_ews, L_wes,L_sns,L_nss) be according to experience it has been determined that function；

Optimizing index according to step 5 (1) and the green conflict constraint of step 3, use linear programming method to determine that each green light is opened Open, the persistent period and need let pass vehicle number；

(3) according to step 4 improve with vehicular traffic flow model of speeding determine clearance vehicle number with let pass the time relation, according to respectively Individual direction needs the vehicle number let pass, and each green light determining step 5 (2) is opened, the persistent period is modified, and determines signal Total cycle.