(Not Applicable)
(Not Applicable)
The present invention relates generally to a method for traffic control, particularly to a method for traffic Jam-Relief in 2 crossing direction in a roadnet.
Currently the most common traffic control method for road network are: RATIO and GREENWAVE. RATIO makes traffic get permit/stop based on the ratio periodically, where the maximum distance of each permit for traffic to move is permit-time multiplied by the set-driving-speed. GREENWAVE partially solves the problem. GREENWAVE greatly decreases the wait-time of the vehicles moving in same traffic direction as the greenwave direction; both directions should be parallel. 2-cross-direction GREENWAVE Lead mode is proposed, and also a traffic Jam-Relief mode in a reverse direction of traffic direction has been filed recently. If traffic jam in a cross direction over the previous traffic Jam-Relief mode direction in a roadnet can also be relieved, then the efficiency of traffic Jam-Relief would be improved further and traffic wait-time would be less.
It is an object of the present invention to realize traffic Jam-Relief greenwave in 2-cross-direction in a roadnet, so as to further expand the effectiveness of traffic congestion relief, decrease traffic wait-time, improve the efficiency of traffic and traffic control.
The main idea of the present invention providing a solution to achieve the above object is, configure all the channels in a direction in a roadnet as traffic Jam-Relief control mode and further change the time-offset of the source-intersections of the channels from the same values to the time-offset in the order of the source-intersections in a cross direction over the Jam-Relief mode direction, the time-offset are calculated also based on a traffic Jam-Relief channel, so that forms 2-cross-direction traffic Jam-Relief in a roadnet. The features of the present invention is as follow:
A method for 2-cross-direction traffic jam-relief greenwave mode in roadnets includes steps:
S1: Initialize signal system as mode RATIO with obtaining the feature parameters of a controlled roadnet, such as a rectangle area of M*N intersections, M columns of D-channels, N rows of D-channels, and the start-time of the jam-vehicle-queues of the road-segments of the D-channels of roadnet, denoted by JVQ-start-time, where the JVQ-start-time equals to JVQ-start-coefficient*queue-length, wherein the JVQ-start-coefficient ranges from 0.14 to 0.22, taking median 0.18, unit: sec/meter, can be dynamically adjustable with the control system;
S2 calculate and configure 2D-Jam-Relief greenwave time-offset for every intersections: 1) setup an origin source-intersection of 2D-Jam-Relief greenwave, which is an influx point of 2 cross jammed traffic direction ends, that's, an intersection at a corner of the rectangle area, set one of the 2 directions as master controlled direction and the other as slave controlled direction, their respective reverse directions as master traffic Jam-Relief greenwave direction and slave traffic Jam-Relief direction, meanwhile, set all the source-intersections of the Jam-Relief greenwave of master D-channels in the rectangle area as slave Jam-Relief greenwave time-offset D-channel, that's, a D-channel at the edge in the rectangle area, 2) calculate Jam-Relief greenwave time-offset of every intersection of every master D-channel: the sum of the JVQ-start-time of the road-segments between a source-intersection and one of its downstream intersections as so-called intersection jam-relief greenwave-offset of the downstream intersection in every master jam-relief greenwave D-channel in the rectangle, 3) calculate slave Jam-Relief greenwave time-offset of every intersections in the slave jam-relief greenwave time-offset channel: the sum of the JVQ-start-time of the road-segments between the origin source-intersection and one of its downstream intersections, the source-intersections of master greenwave D-channel along the slave Jam-Relief greenwave direction, 4) add respectively corresponding master/slave two time-offset and set up for every intersection: add its master jam-relief greenwave time-offset in its master channel and its slave jam-relief greenwave time-offset at the source-intersection of its master channel referring to the 2D origin source-intersection along the slave direction;
S3 run RATIO mode after running out respective 2D-Jam-Relief greenwave-offset of an intersection with red light on or without signals;
Another feature of the present invention is that step S1 includes steps of:
S11 Said JVQ-start-time equals to JVQ-start-coefficient*jam-coefficient*the road-segment-length, where the jam-coefficient is less than or equal to one, “equals to one” means that heavy jam occurs, that's, jammed vehicle-queue-length=the road-segment-length;
Another feature of the present invention is that step S1 includes steps of:
S12 Said jammed vehicle-queue-length minus the length of the queue's upstream intersection without any vehicle multiplied by a value less than or equal to one;
Another feature of the present invention is that step S1 includes steps of:
S13 Said queue-length plus the length of the traffic upstream intersection with vehicles fully filled;
Another feature of the present invention is that step S1 includes steps of:
S14 Said JVQ-start-time=JVQ-start-coefficient*jam-coefficient*road-segment-length*apart-coefficient, where the apart-coefficient is bigger than or equal to one, equals to one for keeping present status, “bigger than one” makes the vehicle queue apart from each other;
Another feature of the present invention is that step S3 includes steps of:
S31 Said “running out” mean that decreasing the 2D-Jam-Relief greenwave time-offset second by second to zero;
Another feature of the present invention is that step S3 includes steps of:
S32 Said “running out” or means increasing a value second by second from zero to the set 2D-Jam-Relief greenwave time-offset;
Note1: Said an intersection is a cross of multiple road-segments, controlled by corresponding traffic signals network, 1) a road-segment means a connection section between two adjacent intersections. 2) a channel means multi tandem-connected road-segments, a channel from one side of a roadnet to the other side without intersection-turn is a straight channel, denoted by D-channel;
Note2: Said features of a roadnet includes the amount of intersections controlled, the distance and the JVQ-start-time of road-segments, the distribution of the intersections; a JVQ start-time means the time from when green-lights open to when the most rear vehicle of the wait queue in front of the green-lights start and move; the roadnet with M*N intersections, denoted by {M,N} or {(0,0),(M−1,N−1)}, which (#,#) represents the intersection coordinates, M columns of D-channel, or said M col-D-channels, N rows of D-channel, or said N row-D-channels; column-road-segments denoted Col. {M, N−1} {==}, represents the total number M of columns of D-channels, each col-D-channel including N−1 road-segments, the m-th col-D-channel with the set of the JVQ-start-time of every road-segments of the col-D-channel denoted as col.m{==}, “==” representative for the corresponding values of road-segments of (N−1) columns; row-road-segments denoted Row{N, M−1} {==}, represents the total number N of rows of D-channels, each row-D-channel including M−1 road-segments, the n-th row-D-channel with the set of the JVQ-start-time of every road-segments of the row-D-channel denoted as row n{==}, “==” representative for the corresponding values of road-segments of (M−1) rows; the total number of road-segments at least N*(M−1)+M*(N−1); the values including the length, JVQ-start-time, or, their fixed, etc; it is not a must for absolute parallelism of road-segments.
Note3: Said Jam-Relief greenwave time-offset of intersection is the sum of all road-segments' JVQ-start-time from their source-intersection to one of its downstream intersections in reversed greenwave direction in the set of the JVQ-start-time of a D-channel, denoted by d#{*}, which are from said Col. {M,N−1} {==} or Row {N,M−1} {==} inserted with the JVQ-start-time=0 of column or row for their source-intersection, “d” represents direction of greenwave, N/North, E/East, S/South, W/West, etc, “#” represents coordinates of an intersection, that's, d#{*}=>d(i,j){*}, such as N(6,2) {0,==} represents intersection (6,2) of North-flow greenwave in a roadnet and the most-south (i.e., the reversed North) end intersection as a source-intersection with JVQ-start-time 0, “==” is the set of the JVQ-start-time of the road-segments in the channel; for D-channel, “#” represents serial number of a D-channel, such as W1 {==,0} representing that west-flow greenwave in a roadnet and the most-east (i.e., the reversed west) end intersection as a source-intersection with JVQ-start-time=0 and all the intersections with j=1; well, S4{==,0} representing that south-flow greenwave in a roadnet and the most-north (i.e., the reversed south) end intersection as a source-intersection with JVQ-start-time=0 and all the intersections with i=4.
The advantages of the present invention are below: the calculation and the simulation within a 7×5 roadnet shows that 2D-Jam-Relief greenwave signals mode obtains higher efficient by 50% in relieving heavy traffic jam in a roadnet than 1D-Jam-Relief greenwave mode, by 100% than mode RATIO, greatly improve the efficiency of traffic signal control and traffic.
East 1 D-channel, intersection(6,0) are changing into its 2nd slave greenwave South green light just finishing the 45 sec of East green light of its 2nd period of 90 secs due to its 2D-Jam-Relief greenwave time-offset[0+0], intersection(5,0) has run for its [27+0] sec, its 1st period of 90 secs, and its 2nd master greenwave East green light for 18 secs, intersection(4,0) has run for its [45+0], its 1st period of 90 secs, and changing into its 2nd master greenwave East green light, intersection(3,0) has run for its [68+0], its 1st master greenwave East green light of 45 secs, and running its 1st slave greenwave South green light for 22 secs, intersection(2,0) has run for its [95+0], its 1st master greenwave East green light for 40 secs, intersection(1,0) has run for its [113+0], its 1st master greenwave East green light for 22 secs, intersection(0,0) has run for 135 secs of its [136+0], 1 sec to complete its [136+0] for opening its master East greenwave green light;
East 2 D-channel, intersection(6,1) has run for its [0+27], its 1st period of 90 secs, and its 2nd East master greenwave for 18 secs, intersection(5,1) has run for its [27+27] secs, its 1st master greenwave East green light for 45 secs, and its 1st slave greenwave South green light for 36 secs, intersection(4,1) has run for its [45+27], its 1st master greenwave East green light for 45 secs, and its 1st slave greenwave South green light for 18 secs, intersection(3,1) has run for its [68+27], its 1st master greenwave East green light for 40 secs, intersection(2,1) has run for its [95+27], its 1st master greenwave East green light for 13 secs, intersection(1,1) has run for 135 secs of its [113+27], 5 sec to complete its [113+27] for opening its master East greenwave green light;
East 3 D-channel, intersection(6,2) has run for its [0+45], its 1st period of 90 secs, and changing into its 2nd East master greenwave, intersection(5,2) has run for its [27+45] secs, its 1st master greenwave East green light for 45 secs, and its 1st slave greenwave South green light for 18 secs, intersection(4,2) has run for its [45+45], its 1st master greenwave East green light for 45 secs, and changing into its 1st slave greenwave South green light, intersection(3,2) has run for its [68+45], its 1st master greenwave East green light for 22 secs, intersection(2,2) has 5 sec to complete its [95+45] for opening its master East greenwave green light;
East 4 D-channel, intersection(6,3) has run for its [0+68], its 1st master greenwave East green light for 45 secs, and its 1st slave greenwave South green light for 22 sec, intersection(5,3) has run for its [27+68] secs, its 1st master greenwave East green light for 40 secs, intersection(4,3) has run for its [45+68], its 1st master greenwave East green light for 22 secs, intersection(3,3) has 5 sec to complete its [68+68] for opening its master East greenwave green light;
East 5 D-channel, intersection(6,4) has run for its [0+95], its 1st master greenwave East green light for 40 secs, intersection(5,4) has run for its [27+95] secs, its 1st master greenwave East green light for 13 secs, intersection(4,4) has run for 135 sec, has 5 sec to complete its [45+95] for opening its master East greenwave green light;
A detailed description of an embodiment of the invention in conjunction with the accompanying drawings:
Create a roadnet as shown in
In
as
In
S1 setup default ratio signal mode: (1) set north as signal main direction for all intersections in a roadnet, cycle=90 seconds, the time ratio for directions=1, each direction 45 seconds, straight/left 2-phase ratio=2, straight phase 30 seconds, left phase 15 seconds; (2) and obtain a rectangle from the roadnet, including 7×5 intersections with 7 col.-D-channels and 5 row-D-channels, and the JVQ-start-time of every road-segment of the channels, JVQ-start-time=JVQ-start-coefficient*jam-coefficient*road-segment-length*apart-coefficient, wherein jam-coefficient is less than or equal to 1, “equal to 1” means heavy jam, apart-coefficient is bigger than or equal to 1, “equal to 1” means keeping-the-present-status, JVQ-start-coefficient based on experimental estimate ranges 0.14˜0.22, taking their median 0.18, letting jam-coefficient=1, heavy jam, vehicle-queue-length=road-segment-length under heavy-jam, and apart-coefficient=1, keeping-the-present-status, ignoring the length of an intersection, so that JVQ-start-time=road-segment-length*0.18; the set of the JVQ-start-time of the road-segments of East D-channels from East 1 {==} to East 5{==} are {23,18,27,23,18,27}, the set of the JVQ-start-time of the road-segments of South D-channels from South 1 {==} to South 7{==} are {27,18,23,27};
S2: calculate and configure the 2D-Jam-Relief greenwave time-offset: 1) setup an intersection at a corner in the rectangle area as an origin of the 2D-Jam-Relief greenwave: that's, intersection(6,0), master/slave Jam-Relief directions: master jammed direction East—slave jammed direction-South, their corresponding master Jam-Relief greenwave direction West—slave Jam-Relief greenwave direction-North, and the set of the source-intersections is col.6{(6,0), (6,1), (6,2), (6,3),(6,4),}, that's, South 6{*}, 2) setup Jam-Relief greenwave time-offset for every intersection of every master greenwave D-channel: the sum of the JVQ-start-time of the road-segments between the source-intersection of a master greenwave D-channel and one of its downstream intersections along their master greenwave direction, 3) calculate Jam-Relief greenwave time-offset of the slave time-offset D-channel, the sum of the JVQ-start-time of the road-segments between the source-intersection, the origin (6,0) of 2D-Jam-Relief greenwave, of the slave time-offset D-channel and one of its downstream intersections along its slave greenwave direction, 4) add the said two time-offset of every intersection: Jam-Relief greenwave time-offset for every intersection of every master greenwave D-channel+Jam-Relief greenwave time-offset of the slave time-offset D-channel, the calculation results are:
Jam-Relief greenwave-time-offset for every intersection of master greenwave D-channel: East 1{*} to East 5{*} are {136,113,95,68,45,27,0},
Jam-Relief greenwave-time-offset of the slave time-offset channel: 1: South 6{*} is {0,27,45,68,95},
the set of 2D-Jam-Relief greenwave time-offset:
East 1{*}={136+0,113+0,95+0,68+0,45+0,27+0,0+0},
East 2{*}={136+27,113+27,95+27,68+27,45+27,27+27,0+27},
East 3{*}={136+45,113+45,95+45,68+45,45+45,27+45,0+45},
East 4{*}={136+68,113+68,95+68,68+68,45+68,27+68,0+68},
East 5{*}={136+95,113+95,95+95,68+95,45+95,27+95,0+95},
Concrete to an intersection, such as the 2D-Jam-Relief greenwave time-offset of the 3rd intersection (2,3) of East 4th D-channel East 4{*} is [95]+[68]=163, the time-offset of the 1st intersection (0,4) of East 5th D-channel East 5{*} is [136]+[95]=231, the time-offset of the origin intersection (6,0) is [0]+[0]=0;
S3: run out the 2D-Jam-Relief geenwave time-offset of each intersection with red signal on or without signal light first, then run RATIO mode, that's: for each intersection, if the 2D-Jam-Relief greenwave-offset >0, display Red signal or no signal, and minus 1, wait for next second, until the 2D-Jam-Relief greenwave time-offset=0, execute mode RATIO.
Number | Date | Country | Kind |
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201710069293.2 | Feb 2017 | CN | national |