Smart junctions: Adopt adaptive signals

Adaptive traffic signals were supposed to be in place years ago, in the city’s Central Business District (CBD) areas and 12 high-density corridors
Last Updated 25 February 2022, 21:00 IST

Heading home from work after dark, the motorcyclist spotted red from a distance. One hundred and twenty seconds later, he was still there, awaiting green. Not a soul, not a single vehicle was in sight. Scientifically designed, smartly coordinated junctions seemed miles away.

Adaptive traffic signals were supposed to be in place years ago, in the city’s Central Business District (CBD) areas and 12 high-density corridors. Last heard, the Karnataka Road Development Corporation Limited (KRDCL) had floated tenders for the Rs 37 crore project on behalf of the city traffic police.

Green corridors

The system was designed to calculate the traffic density on its own, and even transform an entire stretch of road as a green corridor to facilitate quick ambulance movement. Up-gradation and synchronisation of 184 traffic signals were part of the project.

The system's potential to streamline traffic, decongest roads smartly, and ease pedestrian movement has been proven beyond doubt in cities worldwide. Traffic and mobility experts wonder why road users are forced to struggle with an outdated system.

Bengaluru's Joint Commissioner of Police, Traffic, Ravikanthe Gowda informs that the city currently has 35 junctions fitted with the system. But a larger city-wide system to be installed by KRDCL is now going through a technical evaluation, he adds.

“The methods currently used are quite old and static. They are more suited for Western cities where the traffic is homogenous, lane-based and disciplined,” notes transportation engineering and mobility analyst Ashish Verma from the Indian Institute of Science (IISc).

Intelligent signals

To make the signals intelligent, Verma points out, inputs based on traffic data during the morning, evening peak hours and afternoon are required. “We have a largely heterogeneous, non-lane system with the mixing of vehicles heading left and right,” he explains, stressing the need for an improved technology solution that captures all these.

For the motorist, a coordinated system means he/she could pass through a non-stop series of green signals. “This corridor level signal coordination will enable dispatch of vehicles in a platoon through multiple junctions. The present method of timing is outdated, not intelligent and adaptive, and sees each junction as isolated,” notes Verma.

Studies have clearly established that poorly designed signalled junctions are the main source of traffic delay today. Since the city's vehicular population shows no signs of a dip in its explosive growth, the congestion at junctions is only getting worse.

Manual intervention

Manual intervention by the traffic police to alter pre-defined signal timings have only added to the inefficiency, Verma points out.

Synchronised signalling is a concept that has been talked about in Bengaluru for the last three decades, reminds former Director General of Police Ajai Kumar Singh. “In the 1980s, when I was the city's Deputy Commissioner, Traffic, I had even gone to Delhi to study such a system introduced in the Connaught Place area,” he recalls.

Smooth flow of traffic, reduced travel time, fuel-saving... “No doubt, there are several advantages of the system. But it is a complicated one that relies on the distance, the speed and the variety of vehicles approaching a junction. Maybe, that is why it has taken this long for installation,” Ajai Kumar contends.

Signal with counter

Incidentally, he points out, Bengaluru was the first city in India to get a traffic signal with counter. “It was installed near the Sadashivanagar police station sometime in the 1990s as a technology demonstrator by Bharat Electronics.”

Cut to 2019, and the Electronics City Industrial Township Authority (ELCITA) had upgraded six signals with the Dynamic Signalling technology. The concept employed Google Maps to track the magnitude of the traffic at a junction, based on which the signal timing was adjusted.

The system determined the time required for the traffic to move in a particular direction, displaying the green signal on that route accordingly. Experts feel such technologies could be adopted across the city, to rationalise timings, particularly during the night and off-peak hours.

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(Published 25 February 2022, 16:51 IST)

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