Police to retune cycle length of traffic signals

Hopes of commuters in Bangalore that pre-programmed timed traffic signals will be replaced by dynamic vehicle actuated traffic signals are dashed. For, the traffic police have decided not to switch to vehicle actuated signal system for now.

 Additional Commissioner (Traffic and Security)  M A Saleem, told Deccan Herald that they experimented with two kinds of vehicle actuated traffic signals in the City, but found them either ineffective or costly.

A vehicle actuated traffic signal is one that automatically senses the volume of traffic on each aspect or road of the traffic signal and dynamically alternates between the red and the green in proportion to the traffic. The country’s first vehicle-actuated Wireless Traffic Signal Controller (Wi-TraC) started functioning at Trivandrum, Kerala in 2012 and is running successfully.

Recently, an Australian company had installed the system on trial at M S Ramaiah Hospital Junction on New BEL Road and also on MG Road. The system deploys cameras mounted on the traffic signal pole – a camera facing each of the aspect or road of the signal to dynamically track the traffic volume and change signals accordingly. “Though the system was working better, it was very costly. Each such signal was to cost $ 15,000, a huge sum by any standards,” Saleem said.

However, a large number of commuters are not that happy with the existing signal system. Darshan, a software engineer with a leading IT firm in the City, told Deccan Herald, “When I often go home after work, there is not much traffic at these signals, but the cycle has been programmed for the peak hours and thus we are forced to unnecessarily wait even when the roads are relatively free.”

He said that this was true for Sundays and during lean hours on other days.  
Saleem said that in 2008-09, the City traffic police in co-ordination with Bharat Electronics Limited, had implemented on pilot basis a system of vehicle actuated traffic signals at 94 signals across the City. Sensors used to be laid below road surface across all aspects of the traffic signal, which used to sense the vehicle volume on the roads, based on which the signal time cycle was dynamically maintained. But, the sensors went dead with asphalting of roads, rendering the scheme impractical. 

“So, we have decided to retain timer programmed traffic signals in the City for now,” Saleem said. The traffic police have now taken up a survey of all the 324 traffic signals in the City. “Based on the findings of the survey, the signal cycle lengths in the City will be revised,” he said.  

The recent B-Trac Evaluation and Impact Study done by Centre for Infrastructure, Sustainable Transportation and Urban Planning, IISc  recommended: “The cycle length of nearly 98 out of the 324 signals in the City is more than 180 seconds which is too high. The optimum cycle length should be fixed based on traffic volumes,” indicating that the vehicle actuated traffic signals should be implemented.