With cities aiming to make themselves more livable and raise residents’ quality of life, they are increasingly turning to intelligent transportation systems (ITS) to reduce congestion, clean up air and make driving less of a hassle. Among the United Kingdoms’ various municipalities, Cambridge is known for its endeavors to make the city’s transportation smart through ITS.
Right now, Cambridge is engaged in an upgrade project whereby the city’s traffic lights will be connected to its smart traffic management system. According to a
post on the web portal
Smarter Cambridge Transport, upgrading and integrating all the signals on the main roads in the city will have various benefits.
“These include reducing everyday congestion markedly by smoothing traffic flows and prioritizing traffic in response to demand in real time; reducing pollution throughout the city as stop-start driving is inefficient and polluting; and enabling a much more effective response to traffic incidents,” the post said. “It will also provide a perfect opportunity to install monitoring equipment to collect much more detailed traffic and journey data than we have now. Each set of traffic lights will have communication equipment that can be used to transmit anonymous vehicle data, either from ANPR cameras or Bluetooth detectors, and CCTV feeds where appropriate.”
According to the post, there are three components that will make the solution work: traffic lights, queue detectors buried in the road or cameras and a central control system. “The queue detectors tell the control system the state of traffic flow on all the main roads in the city. The system in turn controls the lights to maintain a free flow of traffic within the city,” it said. “Every two seconds the system uses a model of real-world conditions to decide whether there would be an advantage in changing the phasing of any of the lights. What the system software considers an ‘advantage’ may be defined as punctual buses, lower pollution at a particular location, or fewer vehicles queuing on a motorway slip ramp.”
Inbound flow control
In another
post, Smarter Cambridge Transport is proposing another smart transportation solution to reduce congestion within the city: inbound flow control, whereby traffic lights on the edge of the city, working in conjunction with other ITS technologies, release vehicles only as fast as the road ahead can carry them. “By restricting flow at peak times in this way, congestion is experienced (if at all) only at the edges of the city: some of the traffic that would otherwise be sitting in a queue within the city (potentially blocking a junction) is ‘relocated’ to the edge of the city, where there is space (or space can more easily be created) to hold it,” the post said.
The post said that the measure would be beneficial for drivers and bus riders alike. “For drivers, your journey time will be no worse, and mostly likely quicker than now. Advance notice of queuing times will help you calculate your journey time and decide when to travel. Within Cambridge, journey times will be considerably quicker,” it said. “For bus passengers, journey times into and within the city will be much more consistent and quicker.”
Such measure has been tried in other cities in Europe, for example Zurich, and the post said Cambridge should trial it too. “A trial would generate hard data and, hopefully, prove the effectiveness of inbound flow control in achieving improved traffic flow in the city, and hence better bus reliability and journey times. It would also give the systems suppliers a degree of freedom to experiment which, for a relatively pioneering technique (at least in the UK), is essential,” it said.