390:
to them directly. Aside from movable parts, electrical relays are also used. In general, electro-mechanical signal controllers use dial timers that have fixed, signalized intersection time plans. Cycle lengths of signalized intersections are determined by small gears that are located within dial timers. Cycle gears, as they are commonly known, range from 35 seconds to 120 seconds. If a cycle gear in a dial timer results in a failure, it can be replaced with another cycle gear that would be appropriate to use. Since a dial timer has only one signalized intersection time plan, it can control phases at a signalized intersection in only one way. Many old signalized intersections still use electro-mechanical signal controllers, and signals that are controlled by them are effective in one way grids where it is often possible to coordinate the signals to the posted speed limit. They are however disadvantageous when the
19:
231:
466:
preventing congestion or to discourage use of a particular road. This is often done at the request of local residents in areas that have a lot of commuter "just passing through" traffic. Speed is self-regulated in coordinated signal systems; drivers traveling too fast will arrive on a red indication and end up stopping, drivers traveling too slowly will not arrive at the next signal in time to utilize the green indication. In synchronized systems, however, drivers will often use excessive speed in order to get through as many lights as possible.
580:
378:
692:: If power is still available, a flashing amber light is used to warn of an intersection. Methods to distinguish the main road from the secondary road (and hence right of way) include using yield (give way) signs, stop signs or a flashing red light on the secondary road as well as written signage. In some countries including Australia, the road rules outline procedures such as giving way to the right. This system is occasionally used when a traffic signal becomes obsoleted due to a lack of need.
403:
188:, with all red lights flashing, rather than displaying a potentially hazardous combination of signals. The CMU is programmed with the allowable combinations of lights, and will detect if the controller gives conflicting directions, for instance, green signals facing both northbound and eastbound traffic at a cross intersection. Conflict monitors are susceptible to false activation during thunderstorms due to power surges and noise induced by nearby lightning strikes.
69:
162:
470:
558:: 3,400 traffic signals co-ordinated by the Sydney Co-ordinated Adaptive Traffic System (SCATS). Designed and developed by RTA, the system was first introduced in 1963 and progressively developed since then. By October 2010, SCATS was licensed to 33,200 intersections in 144 cities across 24 countries worldwide, including Singapore, Hong Kong, Dublin, Tehran and Minneapolis and Detroit.
422:
and are set up so lights "cascade" (progress) in sequence so platoons of vehicles can proceed through a continuous series of green lights. A graphical representation of phase state on a two-axis plane of distance versus time clearly shows a "green band" that has been established based on signalized intersection spacing and expected vehicle speeds. In some countries (e.g.
434:), this "green band" system is used to limit speeds in certain areas. Lights are timed in such a way that motorists can drive through without stopping if their speed is lower than a given limit, mostly 50 km/h (30 mph) in urban areas. This system is known as "grĂĽne Welle" in German, "vague verte" in French, or "groene golf" in Dutch (English: "
698:: Some traffic lights will not operate at night or when traffic is very light. Some may only operate at particular set times (e.g. during working hours of a major factory) or only during special events such as sports or exhibitions. When not operating, the same measures as with failures are used. The part-time operation has advantages and disadvantages.
421:
a progression of green lights. The distinction between coordinated signals and synchronized signals is very important. Synchronized signals all change at the same time and are only used in special instances or in older systems. Coordinated (progressed) systems are controlled from a master controller
389:
In traffic control, simple and old forms of signal controllers are what are known as electro-mechanical signal controllers. Unlike computerized signal controllers, electro-mechanical signal controllers are mainly composed of movable parts (cams, dials, and shafts) that control signals that are wired
267:
recommended to have local governments to convert their traffic lights to LEDs with battery backups. This would lower the energy consumption and enhance the safety at major intersections. The recommendation was for a system which provides fully functional traffic signals for two hours after the power
101:
is a group of non-conflicting phases which move at the same time. For example, a crossroads with four approach arms could operate in two-stage operation, where each road is given green, or three-stage operation, where the major road is given green, then each side road is given green in turn. A cycle
125:
is the period between changes in signal stages. For example, the vehicular green interval is the period of time that vehicular traffic has a green signal. The interval is fixed in pre-timed control and varied in actuated control. In actuated settings, the minimum interval in the minimum amount of
117:
period is the period between the end of a green signal in one phase and the start of a green signal in the next phase. This normally includes an amber signal on approaches where the green phase is ending and an all red stage, where all signals which are changing are red to allow the junction to
55:
In
Australia and New Zealand, the terminology is different. A "phase" is a period of time during which a set of traffic movements receive a green signal - equivalent to the concept of a "stage" in UK and US. One electrical output from the traffic signal controller is called a "signal group" -
126:
time for which a signal will stay green before changing. This can be as low as 2 seconds for local roads, but may need to be up to 15 seconds for arterial roads. The maximum interval is the maximum amount of time one road will be allowed a green signal, where demand is present on another road.
30:
requires more than sight control and coordination to ensure that traffic and pedestrians move as smoothly, and safely as possible. A variety of different control systems are used to accomplish this, ranging from simple clockwork mechanisms to sophisticated computerized control and coordination
465:
to speed the heavier volume direction. Congestion can often throw off any coordination, however. On the other hand, some traffic signals are coordinated to prevent drivers from encountering a long string of green lights. This practice discourages high volumes of traffic by inducing delay yet
80:
are indications shown to traffic on traffic signal aspects (a single light on a signal head). For example, a green phase gives all traffic from a particular approach the right of way through the junction (bar turning traffic). In the UK, a filter phase allows non-conflicting traffic to make
88:
is any path through the junction which vehicles or pedestrians are permitted to take. A movement is conflicting if these paths cross one another. Normally, conflicting movements are not permitted, except for opposed right or left turns (depending on driving side) or, in some jurisdictions,
460:
In modern coordinated signal systems, it is possible for drivers to travel long distances without encountering a red light. This coordination is done easily only on one-way streets with fairly constant levels of traffic. Two-way streets are often arranged to correspond with
501:
can be used to monitor traffic patterns across a city. Non-coordinated sensors occasionally impede traffic by detecting a lull and turning red just as cars arrive from the previous light. The most high-end systems use dozens of sensors and cost hundreds of thousands of
102:
is one complete sequence of stages. The cycle time is the time it takes for a cycle to complete. Some jurisdictions have maximum cycle times. For example, in the UK this is 120 seconds or 90 seconds where pedestrian facilities are present. Under actuated control, the
238:
Traffic lights must be instructed when to change stage and they are usually coordinated so that the stage changes occur in some relationship to other nearby signals or to the press of a pedestrian button or to the action of a timer or a number of other inputs.
450:
experimented on with this. Many US cities set the green wave on two-way streets to operate in the direction more heavily traveled, rather than trying to progress traffic in both directions. But the recent introduction of the flashing yellow arrow (see article
662:
tag readers are used as inputs as a mean to for monitoring traffic flow. The data is fed through the government-dedicated broadband wireless infrastructure to the traffic management center to be used in adaptive traffic control of the traffic
259:
which consume 85-90% less energy, it is now possible to incorporate battery backups into the traffic light systems. The battery backups would be installed in the traffic controller cabinet or in their own cabinet adjacent to the controller.
72:
This three-arm signal controlled junction has three vehicle phases (A, B and C) and a pedestrian phase (D). The phases operate together in three stages (1, 2 and 3). Moving phases are shown in green and stopped phases are shown in
145:
still had 4,800 as of 1998, though the number is lower now due to the prevalence of the signal controller boxes). However, modern traffic controllers are solid state. The cabinet typically contains a power panel, to distribute
1358:
406:
Diagram demonstrating that when traffic lights are synchronised for traffic travelling in one direction (green arrows), the traffic in the other direction is not necessarily synchronised (blue arrows).
247:
In the areas that are prone to power interruptions, adding battery backups to the traffic controller systems can enhance the safety of the motorists and pedestrians. In the past, a larger capacity of
22:
A junction for road vehicles and pedestrians controlled by traffic lights in the UK. The various vehicle and pedestrian movements are separated in either time or space for safety and efficiency.
1056:
552:: 83% of its signals are controlled by the Main Traffic Signal System (MTSS). 15% also use the SCOOT (Split Cycle and Offset Optimization Technique), an adaptive signal control system.
129:
For pedestrians, an invitation period is the period of time where pedestrians are invited to begin crossing the road. This is normally shown with a green or white male walking figure.
2625:
485:
More recently even more sophisticated methods have been employed. Traffic lights are sometimes centrally controlled by monitors or by computers to allow them to be coordinated in
2298:
481:
is video camera-actuated (just above the vertically-aligned lenses) and also shows the seconds remaining to change to the next state (in the leftmost horizontally-aligned lens)
2640:
1530:
1447:
623:. As of 2013, it is in operation and plans to cover 128 intersections by 2014. To reduce delays due to the planned two-year closure of the northbound lanes of the
173:, which sets standards for connectors, operating limits, and intervals. The TS-1 standard was introduced in 1976 for the first generation of solid-state controllers.
1366:
604:
564:: 3,200 traffic lights across Victoria, including regional areas such as Geelong and Ballarat, using SCATS. Some 500 intersections also have tram and bus priority.
2364:
874:
1387:
1191:
856:
1420:
184:
operation. The CMU monitors the outputs of the controller, and if a fault is detected, the CMU uses the flash transfer relays to put the intersection to
506:
per intersection, but can very finely control traffic levels. This relieves the need for other measures (like new roads) which are even more expensive.
1075:
2608:
546:: 7,660 (of a total of 12,460) signalized intersections are controlled by a central computer network and monitored by traffic management centers.
199:. The project attempts to create a single national standard for traffic light controllers. The standardization effort is part of the National
570:: 580 sets of coordinated traffic lights throughout the metropolitan region managed by the Adelaide Coordinated Traffic Signal (ACTS) System.
2635:
1116:
978:
1504:
2582:
2223:
2153:
1750:
704:: Traffic signals are activated to coincide with the approach of a train, often where the intersection is near a rail crossing. See also
671:
2601:
263:
The battery backups can operate the controller in emergency mode with the red light flashing or in fully functional mode. In 2004,
18:
1329:
1788:
1624:
1476:
2015:
1041:
453:
1534:
438:"). Such systems were commonly used in urban areas of the United States from the 1940s, but are less common today. In the UK,
2432:
843:
800:
792:
196:
713:: Traffic signals are activated to coincide with the arrival of a bus or tram along a busway, bus lane or tramway. See also
627:
that will start around March 2014, this system will synchronize traffic lights at an additional 15 intersections along
2068:
2405:
705:
1175:
192:
2630:
2577:
2569:
2035:
616:
608:
200:
928:
749:
are a rarely used variant to give drivers a recommended speed to approach the next traffic light in its green phase.
2238:
2088:
2286:
1394:
2400:
1588:
1199:
1012:
666:
655:
1252:. IEEE International Conference on Intelligent Transportation Systems (ITSC), Qingdao, China, 2014: 1863-1868.
952:
904:
2243:
2178:
2173:
1970:
1555:
394:
of an intersection would benefit from being adapted to the dominant flows changing over the time of the day.
1072:
264:
248:
39:
The first automated system for controlling traffic signals was developed by inventors
Leonard Casciato and
619:", the first of its kind in the state, with traffic controlled intersections and vehicle detectors in the
1617:
1300:
589:
reader attached to the pole and its antenna (right) used in traffic monitoring in New York City by using
255:. The cost for such system would be prohibitive. After the newer generations of traffic signals that use
154:
and other detectors; detector amplifiers; the controller itself; a conflict monitor unit; flash transfer
138:
2518:
2010:
1975:
1837:
1481:
1448:"'Adaptive' signals will speed up traffic in Jersey City and Kearny during Pulaski Skyway construction"
522:
Reducing unnecessary stopping and starting of traffic - this in turn reduces fuel consumption, air and
1007:
2336:
2291:
1985:
739:
590:
494:
410:
Attempts are often made to place traffic signals on a coordinated system so that drivers encounter a
2661:
2357:
2168:
2053:
2020:
1995:
1940:
1935:
1873:
1868:
1802:
1768:
1037:
686:
is where the timings of the junction or crossing are not linked to any other junctions or crossing.
636:
598:
1584:
230:
2352:
2331:
2158:
1990:
1980:
1915:
1888:
1827:
1778:
1691:
640:
1261:
975:
2379:
2193:
2073:
2000:
1965:
1955:
1950:
1878:
1842:
1822:
1610:
810:
620:
457:) makes the lead-lag signal, an aid to progression, available with protected/permissive turns.
276:
There are a number of types of control mechanisms for junctions controlled by traffic signals:
234:
Battery backups installed in a separate cabinet from the traffic controller cabinet on the top.
118:
clear. All red stages produce lost time, where no road users can proceed through the junction.
624:
2508:
2384:
2276:
2233:
2198:
2138:
2133:
2128:
2118:
2113:
2103:
2098:
2093:
2078:
2063:
2058:
2048:
2043:
2025:
1905:
1863:
1832:
1720:
1702:
1092:
612:
2548:
2478:
2473:
2369:
2281:
2266:
2228:
2218:
2208:
2203:
2188:
2183:
2148:
2123:
2108:
2083:
2005:
1925:
1900:
1847:
1817:
1667:
1647:
632:
628:
385:, featuring a "Walking green man" below a countdown display where the "Red Man" once stood.
650:'s adaptive traffic control system that employs multiple technologies. Cameras, microwave
207:
in 1991, followed by TEA-21, and subsequent bills. The controllers will communicate using
8:
2503:
2374:
2248:
2213:
2163:
2143:
1960:
1930:
1910:
1893:
1883:
1662:
1093:"Senate Bill 84 XX Battery Backup Program for Light Emitting Diode (LED) Traffic Signals"
486:
2463:
2271:
1945:
1920:
1452:
1274:
735:
322:
252:
875:"Josef Kates Found Ways to Unsnarl Traffic and Solve Business Problems With Computers"
839:
796:
216:
579:
2543:
2513:
1783:
1189:
861:
651:
498:
447:
158:; a police panel, to allow the police to disable the signal; and other components.
147:
1249:
995:
346:
No fixed cycle length, detection used on all approaches, responsive to conditions
2538:
1682:
1677:
1079:
982:
817:. U.S. Department of Transportation Federal Highway Administration. October 2005.
523:
141:
mounted inside a cabinet. Some electro-mechanical controllers are still in use (
1133:
726:
or rescue stations have no green, as they may turn only amber and then red when
106:
is the stage which the traffic controller will return to if there is no demand.
2533:
2493:
2458:
1773:
1763:
1740:
1712:
1652:
1155:
727:
377:
251:
would be required to continue the full operations of the traffic signals using
1057:
Choreographing the Dance of
Traffic Lights, New York Times, September 17, 1998
268:
outage. Then the signals will have flashing red lights for another two hours.
2655:
2523:
2498:
2427:
1531:"Removal Of Signal Flashing Mode During Late-Night / Early-Morning Operation"
1421:"During Pulaski Skyway Closure, Traffic Lights to Be Adjusted on Local Roads"
647:
543:
391:
151:
142:
27:
2468:
68:
1758:
1729:
1697:
1633:
1533:. US Federal Highway Administration Office of Safety Design. Archived from
723:
714:
490:
478:
402:
1687:
431:
40:
31:
systems that self-adjust to minimize delay to people using the junction.
1735:
771:
745:
738:
or the like are exiting the station en route to an emergency. See also
731:
435:
411:
256:
57:
516:
Reducing collisions and waiting time for both vehicles and pedestrians
2488:
1725:
1672:
1657:
1224:
561:
533:
462:
443:
181:
161:
2483:
567:
1190:
Department for
Transport, Energy and Infrastructure (2002-08-23).
191:
In the late 1990s, a national standardization effort known as the
763:
659:
586:
549:
423:
220:
44:
1602:
1008:"Traffic Signal Timing Manual: Chapter 5 - Office of Operations"
2553:
1301:"Hands on control: New South Wales Transport Management Centre"
767:
759:
555:
503:
474:
439:
427:
382:
155:
1393:. New Jersey Meadowlands Commission. July 2013. Archived from
519:
Encouraging travel within the speed limit to meet green lights
469:
81:
particular turns (normally left or ahead) through a junction.
2528:
2453:
224:
212:
204:
176:
Solid state controllers are required to have an independent
2641:
Comparison of traffic signs in
English-speaking territories
583:
170:
1388:"Meadowlands Adaptive Signal System for Traffic Reduction"
758:
Traffic light systems are designed using software such as
169:
In the United States, controllers are standardized by the
150:
in the cabinet; a detector interface panel, to connect to
1477:"High-tech signal system helps speed Meadowlands traffic"
605:
Meadowlands
Adaptive Signal System for Traffic Reduction
89:
pedestrians and vehicles moving in parallel directions.
1327:
1298:
1222:
304:
For temporary operation, where detection not available
209:
203:
program funded by various highway bills, starting with
1250:
Real-time traffic control for sustainable urban living
985:, Traffic Signal Training, NIATT / University of Idaho
1052:
1050:
1192:"Adelaide Coordinated Traffic Signal (ACTS) System"
352:Rural, high speed locations or two arterial roads
1505:"New York's award-winning traffic control system"
1047:
513:Increasing the traffic handling capacity of roads
195:(ATC) was undertaken in the United States by the
2653:
2609:Traffic Signs Regulations and General Directions
332:No fixed cycle length, defaults to one movement
1198:. Government of South Australia. Archived from
996:https://tsrgd.co.uk/pdf/tal/2006/tal-1-06_4.pdf
1082:, National Transportation Operations Coalition
782:In the US, there are the following handbooks:
137:A traffic signal is typically controlled by a
1618:
929:"Traffic advisory leaflets from 1989 to 2009"
836:A History of the Austrian Migration to Canada
56:similar to the UK and US concept of "phase".
2636:Comparison of MUTCD-influenced traffic signs
994:DfT Traffic Advisory Leaflet 1/06, Part 4 -
1418:
1272:
1262:NYCDOT Infrastructure & Traffic Signals
1625:
1611:
672:Sydney Coordinated Adaptive Traffic System
2602:Manual on Uniform Traffic Control Devices
1218:
1216:
865:, February 26, 1966, retrieved 2010-10-31
677:
1583:Koonce, Peter; et al. (June 2008).
1242:
1127:
1125:
1098:. California Energy Commission. May 2004
1033:
1031:
1029:
828:
786:
578:
489:to deal with changing traffic patterns.
468:
401:
376:
229:
160:
67:
60:also uses the signal group terminology.
17:
1789:Direction, position, or indication sign
1475:Maag, Christopher (November 29, 2013).
1419:Frassinelli, Mike (September 5, 2013).
1185:
1183:
1117:Learning Traffic Light Control Policies
2654:
2438:Traffic light control and coordination
1582:
1350:
1292:
1275:"Traffic - Frequently asked questions"
1213:
1196:Transport Network - Traffic Operations
1068:
1066:
1064:
1042:Minnesota Department of Transportation
868:
454:Traffic-light signalling and operation
397:
132:
2433:Variations in traffic light operation
1606:
1446:Vena, Joseph R. (September 5, 2013).
1365:. Victoria Government. Archived from
1321:
1156:"Lead-Lag with Flashing Yellow Arrow"
1122:
1026:
1013:Federal Highway Administration (FHWA)
849:
793:Institute of Transportation Engineers
372:
197:Institute of Transportation Engineers
92:
1474:
1445:
1356:
1266:
1180:
1153:
1131:
969:
899:
897:
895:
893:
891:
889:
887:
2406:Traffic signs in post-Soviet states
1061:
953:"Traffic Signal Design Terminology"
905:"Traffic Signal Design Terminology"
574:
271:
13:
811:"Traffic Control Systems Handbook"
787:Seyfried, Robert K. (2013-01-01).
753:
349:Where detection used on all roads
193:advanced transportation controller
14:
2673:
2631:Comparison of European road signs
1632:
1576:
1330:"Review of Operations: Transport"
884:
617:intelligent transportation system
609:New Jersey Meadowlands Commission
242:
201:Intelligent transportation system
789:Traffic Control Devices Handbook
532:Reducing driver frustration and
363:Heavy traffic on arterial roads
165:Computerized traffic control box
1548:
1523:
1497:
1468:
1439:
1412:
1380:
1255:
1169:
1147:
1110:
1085:
834:Engelmann, Frederick C. (1996)
2626:Comparison of Asian road signs
1589:Federal Highway Administration
1000:
988:
945:
921:
667:Scalable Urban Traffic Control
656:radio-frequency identification
615:administration building this "
50:
1:
1328:Roads and Traffic Authority.
1299:Roads and Traffic Authority.
1223:Roads and Traffic Authority.
957:www.traffic-signal-design.com
909:www.traffic-signal-design.com
838:, Carleton University Press,
822:
381:Pedestrian traffic signal in
1585:Traffic Signal Timing Manual
1363:Road Management & Design
1134:"Traffic Signal Progression"
857:The Phony Ogre of Automation
777:
318:Where traffic is consistent
265:California Energy Commission
249:uninterruptible power supply
7:
526:, and vehicle wear and tear
10:
2678:
2519:Polish road signs typeface
1225:"SCATS - Product Features"
711:Bus and Transport Priority
596:
34:
2618:
2593:
2563:International conventions
2562:
2446:
2420:
2393:
2345:
2324:
2259:
2034:
1856:
1810:
1801:
1749:
1711:
1640:
855:McLean, James W. (1966) "
815:FHWA Office of Operations
740:Traffic signal preemption
591:vehicle re-identification
63:
2244:Gaelic-speaking Scotland
1769:Prohibitory traffic sign
1751:Vienna Convention Groups
1587:(Report). United States
1279:Transportation - Traffic
1073:Traffic Signal Standards
599:Adaptive traffic control
1779:Special regulation sign
1511:. January–February 2013
1359:"Traffic Signals SCATS"
1119:URL accessed 2009-03-06
722:Some lights outside of
26:The normal function of
2299:Central America (SICA)
2069:Bosnia and Herzegovina
1248:Xiao-Feng Xie, et al.
678:Other types of control
594:
482:
473:This traffic light in
407:
386:
312:Coordinated pre-timed
235:
166:
74:
23:
2509:NPS Rawlinson Roadway
1736:Give Way / Yield sign
1721:Priority to the right
1703:Variable-message sign
1668:Driver location signs
1337:2009-10 Annual Report
582:
472:
405:
380:
357:Coordinated actuated
233:
180:(CMU), which ensures
178:conflict monitor unit
164:
71:
21:
2016:United Arab Emirates
1648:Advisory speed limit
877:. James R. Hagerty,
646:Midtown in Motion -
529:Reducing travel time
335:Traffic imbalance -
1485:. Woodland Park, NJ
1400:on October 24, 2013
1038:Traffic Signals 101
879:Wall Street Journal
706:Railroad preemption
702:Railroad preemption
696:Part-time operation
398:Coordinated control
360:Fixed cycle length
338:Highway operations
315:Fixed cycle length
301:Fixed cycle length
298:Isolated pre-timed
280:
253:incandescent lights
133:Traffic controllers
2594:National standards
1556:"Flashing signals"
1453:The Jersey Journal
1078:2008-06-26 at the
981:2008-12-16 at the
736:emergency vehicles
720:Emergency Vehicles
611:monitors in their
595:
509:Benefits include:
483:
408:
387:
373:Fixed time control
366:Suburban arterial
279:
236:
167:
93:Stages and periods
75:
24:
2649:
2648:
2416:
2415:
1797:
1796:
1591:. FHWA-HOP-08-024
1509:ITS International
1456:. Jersey City, NJ
1281:. City of Toronto
1273:City of Toronto.
1154:Robinson, Larry.
1132:Robinson, Larry.
844:978-0-88629-283-6
802:978-1-933452-67-8
768:CORSIM/TRANSYT-7F
629:US 1/9 Truck
370:
369:
217:Internet Protocol
2669:
2544:Trafikkalfabetet
2394:Former countries
1808:
1807:
1784:Information sign
1709:
1708:
1627:
1620:
1613:
1604:
1603:
1599:
1597:
1596:
1571:
1570:
1568:
1567:
1552:
1546:
1545:
1543:
1542:
1527:
1521:
1520:
1518:
1516:
1501:
1495:
1494:
1492:
1490:
1472:
1466:
1465:
1463:
1461:
1443:
1437:
1436:
1434:
1432:
1416:
1410:
1409:
1407:
1405:
1399:
1392:
1384:
1378:
1377:
1375:
1374:
1354:
1348:
1347:
1345:
1344:
1339:. NSW Government
1334:
1325:
1319:
1318:
1316:
1315:
1310:. NSW Government
1305:
1296:
1290:
1289:
1287:
1286:
1270:
1264:
1259:
1253:
1246:
1240:
1239:
1237:
1236:
1231:. NSW Government
1220:
1211:
1210:
1208:
1207:
1187:
1178:
1173:
1167:
1166:
1164:
1162:
1151:
1145:
1144:
1142:
1140:
1129:
1120:
1114:
1108:
1107:
1105:
1103:
1097:
1089:
1083:
1070:
1059:
1054:
1045:
1035:
1024:
1023:
1021:
1020:
1004:
998:
992:
986:
973:
967:
966:
964:
963:
949:
943:
942:
940:
939:
925:
919:
918:
916:
915:
901:
882:
872:
866:
862:Montreal Gazette
853:
847:
832:
818:
806:
684:Isolated control
575:Adaptive control
446:had part of the
420:
416:
281:
278:
272:Types of control
148:electrical power
43:and was used in
2677:
2676:
2672:
2671:
2670:
2668:
2667:
2666:
2662:Traffic signals
2652:
2651:
2650:
2645:
2614:
2589:
2558:
2442:
2412:
2389:
2341:
2320:
2255:
2179:North Macedonia
2030:
1852:
1793:
1745:
1707:
1683:Regulatory sign
1678:One-way traffic
1636:
1631:
1594:
1592:
1579:
1574:
1565:
1563:
1554:
1553:
1549:
1540:
1538:
1537:on May 27, 2010
1529:
1528:
1524:
1514:
1512:
1503:
1502:
1498:
1488:
1486:
1473:
1469:
1459:
1457:
1444:
1440:
1430:
1428:
1425:The Star-Ledger
1417:
1413:
1403:
1401:
1397:
1390:
1386:
1385:
1381:
1372:
1370:
1355:
1351:
1342:
1340:
1332:
1326:
1322:
1313:
1311:
1303:
1297:
1293:
1284:
1282:
1271:
1267:
1260:
1256:
1247:
1243:
1234:
1232:
1221:
1214:
1205:
1203:
1188:
1181:
1174:
1170:
1160:
1158:
1152:
1148:
1138:
1136:
1130:
1123:
1115:
1111:
1101:
1099:
1095:
1091:
1090:
1086:
1080:Wayback Machine
1071:
1062:
1055:
1048:
1036:
1027:
1018:
1016:
1006:
1005:
1001:
993:
989:
983:Wayback Machine
974:
970:
961:
959:
951:
950:
946:
937:
935:
927:
926:
922:
913:
911:
903:
902:
885:
881:, July 27, 2018
873:
869:
854:
850:
833:
829:
825:
809:
803:
780:
756:
754:Design software
680:
601:
577:
524:noise pollution
418:
414:
400:
375:
343:Fully-actuated
274:
245:
135:
95:
66:
53:
37:
12:
11:
5:
2675:
2665:
2664:
2647:
2646:
2644:
2643:
2638:
2633:
2628:
2622:
2620:
2616:
2615:
2613:
2612:
2606:
2597:
2595:
2591:
2590:
2588:
2587:
2586:
2585:
2580:
2572:
2566:
2564:
2560:
2559:
2557:
2556:
2551:
2546:
2541:
2536:
2531:
2526:
2521:
2516:
2511:
2506:
2501:
2496:
2494:Highway Gothic
2491:
2486:
2481:
2476:
2471:
2466:
2461:
2459:ASTRA-Frutiger
2456:
2450:
2448:
2444:
2443:
2441:
2440:
2435:
2430:
2424:
2422:
2418:
2417:
2414:
2413:
2411:
2410:
2409:
2408:
2397:
2395:
2391:
2390:
2388:
2387:
2382:
2377:
2372:
2367:
2362:
2361:
2360:
2349:
2347:
2343:
2342:
2340:
2339:
2334:
2328:
2326:
2322:
2321:
2319:
2318:
2317:
2316:
2313:
2310:
2307:
2304:
2296:
2295:
2294:
2284:
2279:
2274:
2269:
2263:
2261:
2257:
2256:
2254:
2253:
2252:
2251:
2246:
2239:United Kingdom
2236:
2231:
2226:
2221:
2216:
2211:
2206:
2201:
2196:
2191:
2186:
2181:
2176:
2171:
2166:
2161:
2156:
2151:
2146:
2141:
2136:
2131:
2126:
2121:
2116:
2111:
2106:
2101:
2096:
2091:
2089:Czech Republic
2086:
2081:
2076:
2071:
2066:
2061:
2056:
2051:
2046:
2040:
2038:
2032:
2031:
2029:
2028:
2023:
2018:
2013:
2008:
2003:
1998:
1993:
1988:
1983:
1978:
1973:
1968:
1963:
1958:
1953:
1948:
1943:
1938:
1933:
1928:
1923:
1918:
1913:
1908:
1903:
1898:
1897:
1896:
1891:
1881:
1876:
1871:
1866:
1860:
1858:
1854:
1853:
1851:
1850:
1845:
1840:
1835:
1830:
1825:
1820:
1814:
1812:
1805:
1799:
1798:
1795:
1794:
1792:
1791:
1786:
1781:
1776:
1774:Mandatory sign
1771:
1766:
1764:Priority signs
1761:
1755:
1753:
1747:
1746:
1744:
1743:
1741:Filter in turn
1738:
1733:
1723:
1717:
1715:
1713:Priority signs
1706:
1705:
1700:
1695:
1685:
1680:
1675:
1670:
1665:
1660:
1655:
1653:Bilingual sign
1650:
1644:
1642:
1638:
1637:
1630:
1629:
1622:
1615:
1607:
1601:
1600:
1578:
1577:External links
1575:
1573:
1572:
1562:(Mailing list)
1547:
1522:
1496:
1467:
1438:
1411:
1379:
1349:
1320:
1291:
1265:
1254:
1241:
1212:
1179:
1168:
1146:
1121:
1109:
1084:
1060:
1046:
1025:
999:
987:
968:
944:
920:
883:
867:
848:
826:
824:
821:
820:
819:
807:
801:
779:
776:
755:
752:
751:
750:
742:
717:
708:
699:
693:
687:
679:
676:
675:
674:
669:
664:
652:motion sensors
644:
633:Route 440
625:Pulaski Skyway
597:Main article:
576:
573:
572:
571:
565:
559:
553:
547:
537:
536:
530:
527:
520:
517:
514:
497:buried in the
399:
396:
374:
371:
368:
367:
364:
361:
358:
354:
353:
350:
347:
344:
340:
339:
336:
333:
330:
329:Semi-actuated
326:
325:
321:City centres,
319:
316:
313:
309:
308:
305:
302:
299:
295:
294:
291:
288:
285:
273:
270:
244:
243:Battery backup
241:
152:loop detectors
134:
131:
94:
91:
65:
62:
52:
49:
36:
33:
28:traffic lights
9:
6:
4:
3:
2:
2674:
2663:
2660:
2659:
2657:
2642:
2639:
2637:
2634:
2632:
2629:
2627:
2624:
2623:
2621:
2617:
2610:
2607:
2604:
2603:
2599:
2598:
2596:
2592:
2584:
2581:
2579:
2576:
2575:
2573:
2571:
2568:
2567:
2565:
2561:
2555:
2552:
2550:
2547:
2545:
2542:
2540:
2537:
2535:
2532:
2530:
2527:
2525:
2524:Rail Alphabet
2522:
2520:
2517:
2515:
2512:
2510:
2507:
2505:
2502:
2500:
2499:LLM Lettering
2497:
2495:
2492:
2490:
2487:
2485:
2482:
2480:
2477:
2475:
2472:
2470:
2467:
2465:
2462:
2460:
2457:
2455:
2452:
2451:
2449:
2445:
2439:
2436:
2434:
2431:
2429:
2428:Traffic light
2426:
2425:
2423:
2419:
2407:
2404:
2403:
2402:
2399:
2398:
2396:
2392:
2386:
2383:
2381:
2378:
2376:
2373:
2371:
2368:
2366:
2363:
2359:
2356:
2355:
2354:
2351:
2350:
2348:
2346:South America
2344:
2338:
2335:
2333:
2330:
2329:
2327:
2323:
2314:
2311:
2308:
2305:
2302:
2301:
2300:
2297:
2293:
2290:
2289:
2288:
2287:United States
2285:
2283:
2280:
2278:
2275:
2273:
2270:
2268:
2265:
2264:
2262:
2260:North America
2258:
2250:
2247:
2245:
2242:
2241:
2240:
2237:
2235:
2232:
2230:
2227:
2225:
2222:
2220:
2217:
2215:
2212:
2210:
2207:
2205:
2202:
2200:
2197:
2195:
2192:
2190:
2187:
2185:
2182:
2180:
2177:
2175:
2172:
2170:
2167:
2165:
2162:
2160:
2157:
2155:
2154:Liechtenstein
2152:
2150:
2147:
2145:
2142:
2140:
2137:
2135:
2132:
2130:
2127:
2125:
2122:
2120:
2117:
2115:
2112:
2110:
2107:
2105:
2102:
2100:
2097:
2095:
2092:
2090:
2087:
2085:
2082:
2080:
2077:
2075:
2072:
2070:
2067:
2065:
2062:
2060:
2057:
2055:
2052:
2050:
2047:
2045:
2042:
2041:
2039:
2037:
2033:
2027:
2024:
2022:
2019:
2017:
2014:
2012:
2009:
2007:
2004:
2002:
1999:
1997:
1994:
1992:
1989:
1987:
1984:
1982:
1979:
1977:
1974:
1972:
1969:
1967:
1964:
1962:
1959:
1957:
1954:
1952:
1949:
1947:
1944:
1942:
1939:
1937:
1934:
1932:
1929:
1927:
1924:
1922:
1919:
1917:
1914:
1912:
1909:
1907:
1904:
1902:
1899:
1895:
1892:
1890:
1887:
1886:
1885:
1882:
1880:
1877:
1875:
1872:
1870:
1867:
1865:
1862:
1861:
1859:
1855:
1849:
1846:
1844:
1841:
1839:
1836:
1834:
1831:
1829:
1826:
1824:
1821:
1819:
1816:
1815:
1813:
1809:
1806:
1804:
1800:
1790:
1787:
1785:
1782:
1780:
1777:
1775:
1772:
1770:
1767:
1765:
1762:
1760:
1757:
1756:
1754:
1752:
1748:
1742:
1739:
1737:
1734:
1731:
1727:
1724:
1722:
1719:
1718:
1716:
1714:
1710:
1704:
1701:
1699:
1696:
1693:
1689:
1686:
1684:
1681:
1679:
1676:
1674:
1671:
1669:
1666:
1664:
1663:Dead end sign
1661:
1659:
1656:
1654:
1651:
1649:
1646:
1645:
1643:
1639:
1635:
1634:Traffic signs
1628:
1623:
1621:
1616:
1614:
1609:
1608:
1605:
1590:
1586:
1581:
1580:
1561:
1557:
1551:
1536:
1532:
1526:
1510:
1506:
1500:
1484:
1483:
1478:
1471:
1455:
1454:
1449:
1442:
1426:
1422:
1415:
1396:
1389:
1383:
1369:on 2011-02-26
1368:
1364:
1360:
1353:
1338:
1331:
1324:
1309:
1302:
1295:
1280:
1276:
1269:
1263:
1258:
1251:
1245:
1230:
1226:
1219:
1217:
1202:on 2009-05-26
1201:
1197:
1193:
1186:
1184:
1177:
1172:
1157:
1150:
1135:
1128:
1126:
1118:
1113:
1094:
1088:
1081:
1077:
1074:
1069:
1067:
1065:
1058:
1053:
1051:
1043:
1039:
1034:
1032:
1030:
1015:
1014:
1009:
1003:
997:
991:
984:
980:
977:
972:
958:
954:
948:
934:
930:
924:
910:
906:
900:
898:
896:
894:
892:
890:
888:
880:
876:
871:
864:
863:
858:
852:
845:
841:
837:
831:
827:
816:
812:
808:
804:
798:
794:
790:
785:
784:
783:
775:
773:
769:
765:
761:
748:
747:
743:
741:
737:
733:
729:
725:
721:
718:
716:
712:
709:
707:
703:
700:
697:
694:
691:
688:
685:
682:
681:
673:
670:
668:
665:
661:
657:
653:
649:
648:New York City
645:
642:
638:
634:
630:
626:
622:
618:
614:
610:
606:
603:
602:
600:
592:
588:
585:
581:
569:
566:
563:
560:
557:
554:
551:
548:
545:
544:New York City
542:
541:
540:
535:
531:
528:
525:
521:
518:
515:
512:
511:
510:
507:
505:
500:
496:
492:
491:Video cameras
488:
480:
476:
471:
467:
464:
458:
456:
455:
449:
445:
441:
437:
433:
429:
425:
413:
404:
395:
393:
392:signal timing
384:
379:
365:
362:
359:
356:
355:
351:
348:
345:
342:
341:
337:
334:
331:
328:
327:
324:
320:
317:
314:
311:
310:
306:
303:
300:
297:
296:
292:
289:
286:
283:
282:
277:
269:
266:
261:
258:
254:
250:
240:
232:
228:
226:
222:
218:
214:
210:
206:
202:
198:
194:
189:
187:
183:
179:
174:
172:
163:
159:
157:
153:
149:
144:
143:New York City
140:
130:
127:
124:
119:
116:
112:
107:
105:
100:
90:
87:
82:
79:
70:
61:
59:
48:
46:
42:
32:
29:
20:
16:
2600:
2437:
2401:Soviet Union
2358:Buenos Aires
2011:Turkmenistan
1976:Saudi Arabia
1838:South Africa
1759:Warning sign
1698:Tourist sign
1593:. Retrieved
1564:. Retrieved
1559:
1550:
1539:. Retrieved
1535:the original
1525:
1513:. Retrieved
1508:
1499:
1489:November 30,
1487:. Retrieved
1480:
1470:
1458:. Retrieved
1451:
1441:
1429:. Retrieved
1427:. Newark, NJ
1424:
1414:
1402:. Retrieved
1395:the original
1382:
1371:. Retrieved
1367:the original
1362:
1352:
1341:. Retrieved
1336:
1323:
1312:. Retrieved
1307:
1294:
1283:. Retrieved
1278:
1268:
1257:
1244:
1233:. Retrieved
1228:
1204:. Retrieved
1200:the original
1195:
1176:SCOOT system
1171:
1159:. Retrieved
1149:
1137:. Retrieved
1112:
1100:. Retrieved
1087:
1017:. Retrieved
1011:
1002:
990:
971:
960:. Retrieved
956:
947:
936:. Retrieved
932:
923:
912:. Retrieved
908:
878:
870:
860:
851:
835:
830:
814:
788:
781:
757:
744:
719:
715:Bus priority
710:
701:
695:
689:
683:
637:Kearny Point
538:
508:
484:
479:Saudi Arabia
459:
452:
409:
388:
323:interchanges
293:Example use
275:
262:
246:
237:
215:), based on
208:
190:
185:
177:
175:
168:
136:
128:
122:
120:
114:
110:
108:
103:
98:
96:
85:
83:
77:
76:
54:
38:
25:
15:
2619:Comparisons
2337:New Zealand
2306:El Salvador
2292:Puerto Rico
2224:Switzerland
2174:Netherlands
1986:South Korea
1971:Philippines
1688:Speed limit
1460:October 16,
1431:October 12,
1404:October 16,
746:Speed signs
734:, or other
728:fire trucks
641:Jersey City
621:Meadowlands
607:(MASSTR) -
432:Netherlands
290:Conditions
51:Terminology
41:Josef Kates
2583:Road signs
2469:Caractères
2303:Costa Rica
2169:Montenegro
2054:Azerbaijan
2021:Uzbekistan
1996:Tajikistan
1941:Kyrgyzstan
1936:Kazakhstan
1874:Bangladesh
1869:Azerbaijan
1803:By country
1692:by country
1595:2010-04-05
1566:2011-10-23
1560:ITETRAFFIC
1541:2011-10-23
1482:The Record
1373:2010-12-11
1357:VicRoads.
1343:2010-12-11
1314:2010-12-11
1285:2010-12-11
1235:2010-12-11
1206:2010-12-11
1102:20 January
1019:2022-04-17
962:2023-08-24
938:2023-08-24
914:2022-10-02
823:References
732:ambulances
539:Examples:
463:rush hours
436:green wave
412:green wave
307:Roadworks
257:LED lights
139:controller
115:intergreen
111:interstage
58:PTV VISSIM
2549:Transport
2489:Helvetica
2479:Clearview
2474:Clarendon
2447:Typefaces
2353:Argentina
2332:Australia
2315:Nicaragua
2309:Guatemala
2159:Lithuania
1991:Sri Lanka
1981:Singapore
1916:Indonesia
1889:Hong Kong
1828:Mauritius
1726:Stop sign
1673:Logo sign
1658:Crossbuck
778:Handbooks
613:Lyndhurst
562:Melbourne
534:road rage
487:real time
444:Berkshire
182:fail-safe
104:reversion
47:in 1954.
2656:Category
2504:Motorway
2484:DIN 1451
2380:Colombia
2312:Honduras
2194:Portugal
2074:Bulgaria
2001:Thailand
1966:Pakistan
1956:Mongolia
1951:Malaysia
1879:Cambodia
1843:Tanzania
1823:Botswana
1076:Archived
979:Archived
846:, p. 184
690:Failures
568:Adelaide
499:pavement
430:and the
287:Meaning
123:interval
86:movement
2578:Traffic
2574:Vienna
2464:Austria
2385:Ecuador
2365:Bolivia
2325:Oceania
2277:Jamaica
2234:Ukraine
2199:Romania
2139:Ireland
2134:Iceland
2129:Hungary
2119:Germany
2114:Georgia
2104:Finland
2099:Estonia
2094:Denmark
2079:Croatia
2064:Belgium
2059:Belarus
2049:Austria
2044:Armenia
2026:Vietnam
1906:Georgia
1864:Armenia
1833:Namibia
1730:all way
764:TRANSYT
663:lights.
660:E-ZPass
658:(RFID)
587:E-ZPass
550:Toronto
504:dollars
495:sensors
424:Germany
419:
415:
221:ISO/OSI
45:Toronto
35:History
2570:Geneva
2554:Tratex
2421:Lights
2370:Brazil
2282:Mexico
2267:Canada
2229:Turkey
2219:Sweden
2209:Serbia
2204:Russia
2189:Poland
2184:Norway
2149:Latvia
2124:Greece
2109:France
2084:Cyprus
2036:Europe
2006:Turkey
1926:Israel
1901:Cyprus
1848:Uganda
1818:Angola
1811:Africa
1161:22 May
1139:22 May
1044:, 2006
976:Basics
933:GOV.UK
842:
799:
772:VISSIM
760:LINSIG
654:, and
593:method
556:Sydney
475:Khobar
440:Slough
428:France
383:Taiwan
223:, and
156:relays
78:Phases
64:Phases
2529:Rotis
2514:Panno
2454:Arial
2375:Chile
2249:Wales
2214:Spain
2164:Malta
2144:Italy
1961:Nepal
1931:Japan
1911:India
1894:Macau
1884:China
1641:Signs
1515:3 May
1398:(PDF)
1391:(PDF)
1333:(PDF)
1304:(PDF)
1229:SCATS
1096:(PDF)
493:, or
284:Type
225:ASN.1
213:NTCIP
205:ISTEA
186:FLASH
99:stage
2611:(UK)
2605:(US)
2539:Tern
2272:Cuba
1946:Laos
1921:Iran
1857:Asia
1517:2014
1491:2013
1462:2013
1433:2013
1406:2013
1163:2014
1141:2014
1104:2014
840:ISBN
797:ISBN
724:fire
639:and
631:and
584:RFID
171:NEMA
109:The
73:red.
2534:SNV
1308:TMC
859:",
770:or
635:in
442:in
121:An
113:or
2658::
1558:.
1507:.
1479:.
1450:.
1423:.
1361:.
1335:.
1306:.
1277:.
1227:.
1215:^
1194:.
1182:^
1124:^
1063:^
1049:^
1040:,
1028:^
1010:.
955:.
931:.
907:.
886:^
813:.
795:.
791:.
774:.
766:,
762:,
730:,
477:,
448:A4
426:,
227:.
219:,
97:A
84:A
1732:)
1728:(
1694:)
1690:(
1626:e
1619:t
1612:v
1598:.
1569:.
1544:.
1519:.
1493:.
1464:.
1435:.
1408:.
1376:.
1346:.
1317:.
1288:.
1238:.
1209:.
1165:.
1143:.
1106:.
1022:.
965:.
941:.
917:.
805:.
643:.
417:—
211:(
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
