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Category Archives: Traffic Control

How to get rid of traffic jams using intelligent transport

I came across a few more online articles recently and this time one article featured mostly intelligent transport systems (ITS). ITS has been around for quite some time now and the big difference between now and a couple of decades ago is the cost for these systems. I would not delve into the details of ITS, and leave it up to the reader to perhaps google about this and all the different types of ITS.

The article “Here’s How to Get Rid of Traffic Jams” presents the various systems that have been implemented in other countries. Some have been implemented one way or the other in some parts of the Philippines, particularly the coordination of traffic signals (Manila, Cebu, Davao) but most have not even been attempted so there’s a lot of room for the improvement especially where congestion is becoming more serious and unmanageable due in part to limitations among agencies and the people themselves who are involved in transport and traffic management.

It also refers to a study on traffic congestion that was conducted for Los Angeles, CA. Reading through the document I couldn’t help but note that much of what LA has experienced and is still experiencing describes what we also try to deal with in Metro Manila and other major Philippine cities. Be sure to browse for the full document and not just the summary for the study. There are also a lot more materials on transport that you can find this website so be sure to bookmark Rand’s website.

Some issues on pedestrian crossings at signalized intersections at BGC

I had heard from friends working at Bonifacio Global City in Taguig that it is difficult for pedestrians to cross at intersections at BGC. For one, the cycle settings (i.e., movements allowed for every green signal) for the intersections, at least those I’ve seen, often had turning traffic in direct conflict with pedestrian crossings. This meant that while given the green light to cross the street, for example, pedestrians had to contend with left turning as well as right turning vehicles who are also allowed movement for particular green phases. The phasing and the cycle settings are definitely more favorable to motor vehicles and assume that motorists will give way to pedestrians already on the carriageway and crossing the street. This is not the case and motorists tend to assert their way against pedestrians. These pedestrians are not jaywalkers but actually have the right of way by virtue of them getting the green light to cross. There is also  that frequently violated rule of vehicles having to give way to legitimate crossings when people are already on the road. This is practiced in many other countries including the US, Japan and Singapore but is lost upon our motorists who seem to believe they own the road.

Another situation I’ve observed and personally experienced is the insufficient amount of time allocated for pedestrians to cross streets. This is particularly true for the wider streets of the Fort where it seems the people who set the signal cycles failed to estimate how much time it requires for people to cover the distance from one side of the roa to the other. What’s more is that the pedestrian settings allow only one or two people to cross at a comfortable pace. That is, other people will have to rush or run to be able to cross. Of course, the pedestrians would have to contend with the

IMG06311-20130628-0853Intersection of 26th Street and 5th Avenue (view along 26th and towards 4th) – notice the green light given to through and left turning traffic as well as the signals for pedestrians, which include countdown timers.

IMG06117-20130531-094426th and 5th (view at the corner facing the Net Lima building)

IMG06118-20130531-094726th and 7th (view from the corner towards The Fort)

The solution to this issue about pedestrian crossings is a little bit more tricky that what seems like something that can be addressed by a simple adjustment of signal settings to provide more time for pedestrians. There is a need to revisit the phasing scheme for vehicle movements allowed at the intersections. Then there is also a need to find the optimum cycle and green time allocations considering the requirements for pedestrians and not just for vehicles. I believe whoever is in charge of the signal settings at BGC should look into this and if they are not capable of adjusting the settings then they should require the provider of the signals to make the necessary adjustments if not show them how to do this considering that traffic is quite dynamic and settings would need to be programmed to be responsive to demand not just for vehicles but pedestrians as well. BGC has great potential to be a pedestrian friendly CBD but whoever is in charge of transport planning and development should step up and level up, so to speak, in providing an environment that will encourage people to walk rather than take their cars. High Street is already there and is an important element in that mix of development but then the cluster of offices and residential condos aren’t exactly designed for efficient walking, and the settings for the intersection signals, as we pointed out, need to be adjusted for pedestrians.

Professorial Chair 2012 presentations on Transportation

The Transportation Engineering Group of the Institute of Civil Engineering of the University of the Philippines Diliman held a special session for its Professorial Chair Lectures last August 10, 2012 at the Toyota Training Room of the National Center for Transportation Studies. Four lectures were delivered by ICE faculty members who are also Research and Extension Fellows at the NCTS. Following are a few photos taken during the colloquium.

Dr. Sean Palmiano presenting on the Investigation of Road Crash Causal Factors in Metro Manila (DMCI Developers Professorial Chair)

Dr. Karl Vergel presenting on the Design of Traffic Signal Timing and Traffic Impacts of the Re-Introduction of Traffic Signal Control at the Intersection of the University Avenue and Commonwealth Avenue (Maynilad Professorial Chair)

Dr. Ric Sigua presenting on Microscopic Simulation: A Tool for Evaluation of Traffic Schemes (Prof. Emeritus Norbert S. Vila Professorial Chair)

Dr. Regin Regidor presenting on Revisiting the Costs of Traffic Congestion in Metro Manila and their Implications (Pozzolanic Philippines, Inc. Professorial Chair)

Audience consisting of various participants including those from the DPWH, DOTC and MMDA who were invited for the colloquium.

Graduate students and technical staff from the College of Engineering and the National Center for Transportation Studies also attended the lectures. Unfortunately, classes were suspended that week due to the monsoon rains that resulted in widespread flooding in Metro Manila so undergraduate students were not able to attend the colloquium.

The presentation files may be found in a previous post where links for downloading are provided. These may also be found in the NCTS website.

Undergraduate research topics on transportation 2011-2012

The Institute of Civil Engineering of the University of the Philippines Diliman is conducting its undergraduate research colloquium today. Expected to present are students who are either at the proposal stage or completing their research. Topics being completed are the following:

  • Analysis of Road Accidents Involving Children Below 15 Years Old
  • Analysis of the Impact of Billboards on Road Accidents Along EDSA
  • Assessment of the Parking Management System in Shopping Malls
  • In-Depth Comparative Analysis of Female and Male Bus Drivers for Public Transport in Metro Manila

Meanwhile, topics being proposed are the following:

  • Accident Risk by Mode of Public Road-Based Passenger Transport in Metro Manila
  • Analysis of Operations of Electric Tricycles
  • Applicability of Unconventional Transit Systems in Selected Metropolitan Areas in the Philippines
  • Assessment of the Philippine National Railways Commuter Line Services
  • Assessment of the Re-Introduction of Traffic Signal at the University Avenue-Commonwealth Avenue Intersection
  • Development of a Public Transport Information System for the UP Diliman Campus
  • Estimating Ridership for a Proposed Public Transport System for UP Diliman
  • Measuring Delay Caused by U-turn as Traffic Control Facility
  • Quantitative Assessment of Road Safety Initiatives Along EDSA
  • Travel Time Estimation of Jeepneys: The Case of University of the Philippines Diliman, Quezon City

The coverage of undergraduate research this year concerns mainly public transportation and road traffic safety but with one topic dealing primarily with traffic engineering. It is hoped that these researches would be able to answer certain nagging questions pertaining to transport and traffic particularly where safety and efficiency are concerned. In the case of topics on mass transport such as those on the PNR commuter services and the applicability of unconventional systems such as the automated guideway transit (AGT) and the monorail, the potential outcomes may actually be able to address questions that concern alternatives or options to road-based transport. This is essential and presently a very relevant issue given the shortcomings in transport infrastructure in many Philippine cities and the current efforts exploring the possibility and feasibility of systems that will alleviate congestion and address travel demand. Overall, such researches are targeted towards contributing to the body of knowledge that should serve as inputs to the formulation of solutions suitable for the Philippine setting.



Among the things you get to observe at signalized intersections are the behavior of drivers given the setting of the traffic lights. While the cyclic transition from red to green to amber and then to red again seems routine and possibly trivial to many, it is an opportunity for traffic engineers to examine how drivers react to the lights. Among the most notable behavior are common violations like beating the red light and occupying the area within the yellow box despite full awareness that the exit is already full.

Then there are the not so obvious but risky habit of some drivers to beat the green light. That’s when a driver anticipates the green light and proceeds to move prior to the signal and before the intersection is clear of any vehicles or pedestrians that may have been caught in the change in signals. It is a practice that increases the probability of a road crash occurring as the clearance interval for vehicles whose paths may be in conflict is drastically reduced. This is a habit of many drivers who are familiar with the sequence of signals at an intersection and who know when its their turn for the green light.

In most cases, drivers and pedestrians are unaware of the length of time available for them to cross the street or intersection. There are no indications for when the lights will change and only familiarity would allow for drivers or pedestrians to estimate when it would be their turn to proceed. In Japan, many intersections play music during that tends to speed up when the signal will be changing. This audible indicator allows for both the blind and the busy to know whether it is safe to cross the street and if there is enough time to do so. It is also something that is probably taught to children for them to more easily know when it is safe for them to cross the street.

There is another innovation to traffic signals that is surely welcome to pedestrians and motorists alike but which may also have its disadvantages. I am referring to the countdown timer, which provides road users the information about the lengths of green and red signals (Note: Amber or yellow is usually fixed at 3 seconds.).  From the perspective of energy efficiency, such information may allow motorists to turn off their engines, usually done when one practices eco-driving, resulting in fuel savings. Meanwhile, drivers of vehicles approaching an intersection may be able to tell if there is enough time for them to do so, and if there isn’t enough time they may be able to slow down their vehicles to stop at the next red light. Countdown timers may also be a helpful tool for enforcement as the timers establish that a driver should be aware of the time. Thus, a driver can no longer reason with the apprehending officer that he/she was not aware of the remaining time for movement.

Pedestrians may also benefit from the knowledge of available time to make a safe crossing. This information should ultimately reduce the need for running in order to completely cross the street. The photo below shows the new countdown timer installed for the southbound through movement at the Katipunan Avenue (C5) – C.P. Garcia Avenue intersection.

One possible disadvantage would be that aggressive drivers may still try to beat the red light by speeding up upon knowing what amount of time is available for them. Another disadvantage relates to beating the green light as even those unfamiliar with the signal sequence will have the information of how much time remains before they can proceed. Thus, many driver and riders start revving up their engines and push on their gears to anticipate the green signal. You can even imagine the countdown timer being used as if it were ticking towards to start of a race.

Despite the disadvantages mentioned, countdown timers should prove to be more beneficial than detrimental in most situations. In fact, countdown timers like the ones already installed at intersections in Bonifacio Global City should enhance traffic safety provided that these devices are fully complemented by enforcers who would flag down motorists and pedestrians who would attempt risky actions in relation to the timing device. Of course, from the research perspective there needs to be a scientific assessment of the actual impacts of countdown timers much like the studies already conducted elsewhere to determine and even measure the effects of these devices on both motorists and pedestrians. Only then can we truly say if they do enhance safety and promote more efficient operations at a signalized intersection.

Full circle with the U-turns: Traffic Signals in Metro Manila

Since last week, it seemed as if a ghost of Christmas past has come to haunt me and my colleagues at the NCTS. We had some unexpected visitors from the Traffic Engineering and Management (TEAM) group of the Department of Public Works and Highways (DPWH). They were at the Center to consult about a project being formulated by the group together with the MMDA for new traffic signals for Metro Manila. DPWH-TEAM has a long history with NCTS starting when that unit was created when the Philippines invested on its first coordinated traffic signals in the 1970s.

At that time, the NCTS was still the Transport Training Center (TTC), and was the site of the first traffic control center for signals that were installed along Quezon Avenue. The package was funded by a loan from the Japanese government and hence involved traffic signals manufactured by Mitsubishi. Years and many TEAM project phases later, most of Metro Manila’s major intersections would be signalized and traffic signal control would be under the Traffic Engineering Center, which until 2003, was under the DPWH. In the 1990’s, the TEC and TEAM worked together to acquire the Sydney Coordinated Adaptive Traffic System (SCATS), which at the time was already installed and running in most major intersections in Cebu City.

SCATS was supposed to usher in a new era in traffic control in Metro Manila until some major problems eventually plagued its operation. One of these problems was power. However, this was something everybody else was concerned with because of the power crisis of the early 1990s. It was also something that seemed to be easily solvable with the acquisition and installation of uninterrupted power systems (UPS) and generators that allowed the facility to operate even during blackouts.

Another technical problem cropped up just about the same time when the TEC and TEAM people were trying to solve the power issue. This time, it was something much more complicated and perhaps, what led to the system losing its credibility in Metro Manila and a chain reaction of sorts in as far as reactions go. The communications problem was a critical one and rendered the system practically unreliable for what it was supposed to solve – congestion. SCATS required a reliable network for its controllers and computers to communicate with each other. This communication allowed its software to assess network-wide traffic demand measured by means of detectors embedded in the pavement at each approach lane of an intersection. Data from these detectors are transmitted to computers in the control center, which then compute for  the optimum cycle times for each signalized intersection. The computers determine which intersections need to be coordinated and how (i.e., alternating or simultaneous), and this process allows SCATS to adapt to variations in traffic. Hence, its name which seemed only appropriate given its performance in what is now the expanded network in metropolitan Cebu.

The failure of SCATS in Metro Manila was further hastened by traffic enforcers who were only too eager to intervene. This intervention was more of interference as enforcers started switching the traffic signal controllers to manual mode at the slightest indication that the signals would appear to be non-responsive to changes in the traffic situation. In truth, it takes a few minutes for the detectors to collect data and send it to the computers that will compute for the appropriate cycles and signal settings as well as determine which intersections to “marry” and “divorce” – to borrow terms used by traffic engineers in Cebu City for the process of coordinating intersections throughout the day. Due to this rampant practice by enforcers in Metro Manila, it was only a matter of time before SCATS was declared a failure and claims were made that Metro Manila traffic is so much more complicated than Cebu’s, where SCATS was a success (it still is today).