Transit Signal Priority for Public Transport & Buses

The basic concept of Transit Signal Priority (TSP) includes different operational changes through technology that decrease stop time at traffic signals for transit vehicles. It either holds green lights longer or shortens red lights. Such changes in public transport movements at crossings are an excellent way to undo the mess with the public transport travel time and increase schedule reliability. 

There are primarily two sorts of TSP:

Passive Traffic Signal Priority – In the Passive system, as per the average public transport vehicle speed, the traffic signals are arranged to turn green. 

Active Traffic Signal Priority – In the Active TSP system, the bus transmits a signal to the traffic signal controller. 

Let us read more on other active traffic signal priority systems:

• Dedicated priority – phasing changes;
• Longer Green Time – timing changes;
• Phase & Timing Change;
• Intelligent Transport Systems (ITS).

Dedicated Priority – Phasing Changes

The most simplistic TSP's turn the signal green for public transport every time the vehicle advances. These systems regulate the traffic signal 'phasing' while an advancing tram sends a message to the traffic signal. However, the action is not immediate as the original phase must end before the signal turns green. 

Though the phasing changes aren't prioritized as traffic signal control systems work consistently in many areas, this system can cause traffic congestion.

Longer Green Time – Timing Changes

The traffic congestion issues that arise at times due to priority systems could be adjusted with the traffic signal timing. It basically involves the actual time provided to the tram's/bus traffic signal 'phase.' The basic thing is to adjust the time once the bus or tram sends a message to the traffic signal controller.

 It is crucial for traffic engineers and public transport planners to work effectively on this plan of stops and Bus Signal Priority systems. The purpose is to keep the bus schedule sure.

Phase & Timing Change: Zurich

Zurich formed a good approach to TSP that connects both timing and phasing changes into a unified system. 

The system blends an electronic forecast of when buses will arrive at a traffic signal with a flexible way to traffic signal 'phasing' and 'timing.' The automatic prediction system is much simpler wherein induction loops in the street sense tram/ or bus is passing over them. With the clear indication of travel time between the sensor and the intersection, the traffic signal receives a warning in the form of the arrival of the tram or bus ( say 20-seconds away). Added sensors report updated data to the traffic signal for the better signal setting.

After securing the information on us or the tram approach, the traffic signal controller determines the best combination of 'phases' and 'timing' so that the public transport vehicle receives a green light exactly when it needs it. It is essential because if nothing is moving, the traffic walks against the light. It is more of a safety issue as often; the drivers complain that the traffic signal was red for no reason.

The Zurich system's unusual thing is that it works with 'phasing' and 'timing.' 

Intelligent Transport Systems (ITS) -

Intelligent Transport Systems (ITS) is a fantastic technology application to improve all kinds of transportation networks and services. The traffic signal control systems (including Transit Signal Priority) constitute a significant part of the ITS Toolkit.

Synopsis - With more advanced computing technology, general mobile communications, and constant sensor technology used all over means a lot of work for traffic signal systems. It is essential to have an accurate Priority Management System with the best navigation technology and secure RF communication that detects equipped transit, emergency, and municipal vehicles and places preference or preemption requests to intersection signal-control equipment.