Traffic control is an important consideration for any city or organisation. It helps ensure the safety of pedestrians and drivers and provides a sense of order and clarity for those unfamiliar with your area. Traffic management systems are typically composed of physical components such as stop signs and traffic lights and software that helps direct people in a way that makes sense from an organisational standpoint. This article will explain the basics of traffic management systems.
What Is A Traffic Control System?
A traffic control system is any technology that helps regulate the flow of vehicles, pedestrians and other modes of transportation around an area. These systems may include:
- Stop signs
- Traffic lights (including pedestrian crossing signals)
- Speed bumps or rumble strips
- Lane dividers
- Roads with a higher capacity
Basic Components of Traffic Control System:
- Cycle Length: The cycle length refers to the time between each traffic light phase. For example, if there are two phases, one for eastbound and one for westbound traffic on a four-way intersection, the cycle length would be two seconds (one second going through each phase).
- Fixed Cycle Length: Fixed cycle length is a system in which each phase has a set amount of time, and traffic flow through the intersection does not interact with any other movement. This system is used most often as it allows for efficient traffic flow without much thought to coordination between modes. A fixed cycle length can also be used with coordinated signals to improve capacity and reduce intersectional congestion.
- Pedestrian Walk Interval: The pedestrian walk interval is the number of times pedestrians have to cross an intersection. Depending on local regulations, it can be about 5 seconds or 30 seconds. Typically, the longer a pedestrian walk interval, the fewer people will choose to use it and opt for other modes of transportation (typically driving). Therefore, the benefit of this interval is that it can reduce conflicts between vehicles and pedestrians at intersections.
- Transition Intervals: Transition intervals are critical to the traffic control cycle. The purpose is to give enough time for pedestrians to clear the crosswalk before other signals change. These intervals typically last longer than pedestrian clearance intervals but shorter than green signal phases. The length of the transition interval depends on the type of intersection, although there are general standards for most intersections. For example, if an intersection has a four-way stop sign or red light, you can expect each direction to be given at least 100 seconds (1 minute) of green time during their respective cycles. It allows all other signals to cycle through their phases before returning to the initial state.
- Presence Detection Systems: A presence detection system is a traffic control system that uses sensors to detect when vehicles are present on the road. You can use these systems for many different purposes, but they’re most commonly used in dynamic speed limit signs along highways and other major roads. A presence detection system typically consists of two main parts: an antenna and a sensor. The antenna sends out radio waves that bounce off passing cars and other objects—like people, animals, or stationary objects like roadside guardrails or trees—and return to the antenna at varying levels of strength depending on how far away they are from it. The sensor measures these signals to determine if something is in front of it using time-of-flight (TOF) technology.
Traffic control cycle systems are the foundation of modern traffic signal operation. They guide drivers and pedestrians, allowing them to move through an intersection with minimal confusion or delay. The design of cycle length is critical for these systems because it determines how long each signal phase will last, affecting throughput at busy intersections with higher traffic volumes. In addition, several types of pedestrian signals give pedestrians priority over drivers during certain periods throughout the day; these include pedestrian walk intervals (PWIs) and pedestrian clearance intervals (PCIs). Finally, presence detection systems use automatic sensors combined with computer technology to determine if vehicles are waiting at red lights and adjust timing accordingly!