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Hey the buzz word in managing Bangalore traffic is "signal free" ?
I am not sure its going to work too well sir, I come from the networking world and have designed and managed some internet data traffic. On the network the general concept is to

a) provision for fatter pipes (if feasible)
b) else prioritize depending on the type of traffic.

The first option is always not a long term solution we get users and software that will anyway clog up bandwidth.
So lets go to the second option and that is to allow certain types of data packets to travel faster than the others Along with this we also introduce some thing called delay pools (traffic signals) which seems to be working for the Internet traffic.

So lets get back to Bangalore roads, in a long stretch (eg Vidhana soudha to BIAL airport) the intent is to have the stretch signal free. Luckily for us its not yet signal free! and that is the reason why its still reasonably manageable. If the 30 odd KM stretch is made signal free and vehicles are traveling at an average of 50 kmph can we visualize the event of a breakdown or an accident? How are the traffic de-congestion planners going to solve this mess? I am trying to highlight the fact that each signal acts as a "delay pool" and brings in some uniformity in the traffic movement. Have a look at this video :

-- PhotoYogi

Disclaimer: I used to be a fan of the signal free traffic idea untill i gave it a deeper thought. I don't claim to be an expert but I do claim i have common sense.

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PY - thanks for the video. I have read a description of the phenomenon shown on the video by the author of this video in the past. It makes a lot of sense.

People think of bottle necks in only one way i.e. when 2 lanes narrow down to one - so we try and get rid of footpaths and solve the problem. Our planners seem to look at signals in exactly the same way.

In the past I have highlighted that we can have bottle necks on the most well planned roads - simply put, when demand exceeds capacity we have a bottle neck (even on widest of roads).

But with no more trees to cut and go any wider, our planners decide to increase speed of travel. Never have they paused to think of the dynamics between speed and road capacity. This is because vehicles do not come to a halt instantly and a safe gap needs to be kept between two vehicles when in motion. It takes 40 feet before a vehicle stops when traveling at 32 km per hour. It takes 120 feet at 64 km per hour. Thus when vehicles trvel faster they have to be separated by wider distances to avoid accidents. Simple caluculation thus can prove that a 1 km long road with speed limit of 32km has capacity to carry 82 vehicles while at double the speed it will carry only 27 vehicles. By allowing more vehicles at more speeds travel becomes less reliable and accidents increase - this leads to more delays than at lower speeds. It is for this reason that worldwide, variable speed limits are in use on modern roads (when number of vehicles on a road increases, speed limit is more restrictive).

And in all this as usual they will ensure that we Indians (forget how to walk and) become a sub-species of human race to have evolved in to beings with two limbs in  years to come. Soon we will have no use for our legs - I know people who drop their kids off to tutions on opposite side of road by scooter because its impossible to cross - and hence in keeping with principles of biological evaluation, they will become rudiments or mere apandages.

ASJ

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Went through the Hindu news item and as well as the Psaram's blog. I think we should not rush with our pessimism and pre-determination on BBMP's plans. The "signal-free" is a misnomer. In fact these are not signal free junctions plan. Signal free is only for one traffic only. Other traffic is regulated with signal (Manual/automated) regulated. I am quite sure BBMP would try to replicate the Bellary Road magic boxes experiment. If the MB is executed is right it will be  an exercise to prioritize the traffic flow.

 I think, it is obligation on part of Praja community to put out all the facts, solutions and shortcomings if any with this plan from BBMP. Lets not rush with our pre-judged notions and generalized one liners. One way to support or demolish the BBMP's idea is to analyze the plan with lot more on ground data and details. Lets assume that BBMP has asked Praja to provide its feedback on its plans. In that context what would we suggest to BBMP? My take would be:

1. I will go with assumption that we need signal free junctions for through traffic to Hosur & vice versa.
2. Map each of these junctions

• Vellara Junction
• Langford Road
• Audogudi Junction
• Forum Mall Junction
• Sarjapur Junction
• Madivala police Station
• Kendriya Sadan junction
• Marigowda Junction
• Anepalya
• Bannerghatta Road

1. What other roads meet at this junction?
2. Road widths in all 4 directions?
3. Vicinity Details? Foot Path, Bus Stops etc.
4. Ped Xing needs?
5. Left/Right/U turn turn feasibility

 I am sure these data points are not that difficult to obtain for a holistic feedback to BBMP.  Based on this input one can come up with a comprehensive feedback along with recommendations to BBMP.

 Syed

 

 

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It was indeed a good video provided by Photoyogi. I was really impressed by it. The shock wave experiment is a very good example to study, in the context of signal free traffic.

I am sure being in NAL photoyogi must be aware that Mach number 1.0 has been exceeded long back by fighter as well as passenger aircrafts. We also know very well how Mrs Chawla died when the space shuttle failed, while re entry. We have seen the Death well when we were young enough to enjoy the exploits of expert Bike riders who drove the bikes parallel the ground in the well. However it is common sense that roads are not provided to test shock wave effect Photoyogi sir.

Bangalore knows very well what in bike racing in midnight in empty roads. Recently my three Morning walk friends were killed on the road by a car being driven “signal free” condition in the early morning hours.

Your concern Photoyogi sir is very well taken. I agree 100%. However I would like to ask whether the discussion is going off the tangent.

The experiment you quote is single track. We are talking about multiple lane traffic. If a person is in such a great hurry he can take the fast lane in signal free traffic. He will be booked if he exceeds the limits jeopardizing other peoples lives. There were several threads erlier in Praja regarding this aspect.

Finally what we are saying is that if it takes the same time for a person coming to office from Mysore as one takes coming from a Bangalore suburb on his own vehicle, there is something wrong.

Does it make any sense? I wonder.

PSA

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Probably we should be meeting the CISTUP at IISC too. I have a presentation lined up on the subject.

ADHOC solutions are a night mare. Sure!

PSA

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