Traffic comprises pedestrians, vehicles, ridden or herded animals, trains, and other conveyances that use public ways (roads) for travel and transportation.
A ramp meter, ramp signal, or metering light is a device, usually a basic traffic light or a two-section signal light together with a signal controller, that regulates the flow of traffic entering freeways according to current traffic conditions. Ramp meters are used at freeway on-ramps to manage the rate of automobiles entering the freeway. Ramp metering systems have proved to be successful in decreasing traffic congestion and improving driver safety.
An intersection or an at-grade junction is a junction where two or more roads converge, diverge, meet or cross at the same height, as opposed to an interchange, which uses bridges or tunnels to separate different roads. Major intersections are often delineated by gores and may be classified by road segments, traffic controls and lane design.
A pedestrian crossing is a place designated for pedestrians to cross a road, street or avenue. The term "pedestrian crossing" is also used in the Vienna and Geneva Conventions, both of which pertain to road signs and road traffic.
Traffic lights, traffic signals, or stoplights – also known as robots in South Africa – are signalling devices positioned at road intersections, pedestrian crossings, and other locations in order to control the flow of traffic.
A controller area network is a vehicle bus standard designed to allow microcontrollers and devices to communicate with each other. It is a message-based protocol, designed originally for multiplex electrical wiring within automobiles to save on copper, but it can also be used in many other contexts. For each device, the data in a frame is transmitted serially but in such a way that if more than one device transmits at the same time, the highest priority device can continue while the others back off. Frames are received by all devices, including by the transmitting device.
The G Line is a bus rapid transit line in Los Angeles, California, operated by the Los Angeles County Metropolitan Transportation Authority (Metro). It operates between Chatsworth and North Hollywood stations in the San Fernando Valley. The 17.7-mile (28.5 km) G Line uses a dedicated, exclusive right-of-way for the entirety of its route with 17 stations located at approximately one-mile (1.6 km) intervals; fares are paid via TAP cards at vending machines on station platforms before boarding to improve performance. It is one of the two lines in the Los Angeles Metro Busway system.
The 1995 Fox River Grove bus–train collision was a grade crossing collision that killed seven students riding aboard a school bus in Fox River Grove, Illinois, on the morning of October 25, 1995. The school bus, driven by a substitute driver, was stopped at a traffic light with the rearmost portion extending onto a portion of the railroad tracks when it was struck by a Metra Union Pacific Northwest Line train en route to Chicago.
Halifax Transit is a Canadian public transport service operating buses and ferries in Halifax, Nova Scotia. Founded as Metro Transit in March 1981, the agency runs two ferry routes, 66 conventional bus routes, three regional express routes, and three rural routes. Halifax Transit also operates Access-a-Bus, a door-to-door paratransit service for senior and disabled citizens.
Signal timing is the technique which traffic engineers use to distribute right-of-way at a signalized intersection. The process includes selecting appropriate values for timing, which are implemented in specialized traffic signal controllers. Signal timing involves deciding how much green time the traffic signal provides an intersection by movement or approach, how long the pedestrian WALK signal should be, whether trains or buses should be prioritized, and numerous other factors.
The yellow trap is a potentially dangerous scenario relating to turns at a traffic light-controlled intersection across oncoming traffic without a protective turn signal; for right-hand traffic, this refers to a vehicle attempting to make a left turn without a permissive/protective left-turn signal.
Traffic signal preemption is a system that allows an operator to override the normal operation of traffic lights. The most common use of these systems manipulates traffic signals in the path of an emergency vehicle, halting conflicting traffic and allowing the emergency vehicle right-of-way, thereby reducing response times and enhancing traffic safety. Signal preemption can also be used on tram, light-rail and bus rapid transit systems, to allow public transportation priority access through intersections, and by railroad systems at crossings to prevent collisions.
In traffic engineering, there are regional and national variations in traffic light operation. This may be in the standard traffic light sequence or by the use of special signals.
The Sydney Coordinated Adaptive Traffic System, abbreviated SCATS, is an intelligent transportation system that manages the dynamic timing of signal phases at traffic signals, meaning that it tries to find the best phasing for a traffic situation. SCATS is based on the automatic plan selection from a library in response to the data derived from loop detectors or other road traffic sensors.
A queue jump is a type of roadway geometry used to provide preference to buses at intersections, often found in bus rapid transit systems. It consists of an additional travel lane on the approach to a signalised intersection. This lane is often restricted to transit vehicles only. A queue jump lane is usually accompanied by a signal which provides a phase specifically for vehicles within the queue jump. Vehicles in the queue jump lane get a "head-start" over other queued vehicles and can therefore merge into the regular travel lanes immediately beyond the signal. The intent of the lane is to allow the higher-capacity vehicles to cut to the front of the queue, reducing the delay caused by the signal and improving the operational efficiency of the transit system.
The normal function of traffic lights 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 systems that self-adjust to minimize delay to people using the junction.
SEA Signalisation is a French company that manufactures traffic lights.
A protected intersection or protected junction, also known as a Dutch-style junction, is a type of at-grade road junction in which cyclists and pedestrians are separated from cars. The primary aim of junction protection is to help pedestrians and cyclists be and feel safer at road junctions.
The King Street Transit Priority Corridor is a transit mall located along King Street between Jarvis and Bathurst Streets in Toronto, Ontario, Canada. It passes by two subway stations on Line 1 Yonge–University. The corridor was created by the King Street Pilot Project to improve streetcar reliability on downtown King Street. The corridor went into operation on November 12, 2017, and was made permanent by City Council on April 16, 2019. The corridor is 2.6 km (1.6 mi) long and spans 18 street intersections.
Traffic lights – devices positioned at road intersections, pedestrian crossings and other locations – control flows of traffic with social norms and laws created by the state. Traffic signals have to convey messages to drivers in a short period of time about constantly-changing road rules.
