MegaCities - Traffic and Transport Solutions

Urban travel is changing. In the future, sensors will monitor traffic flows, while traffic light control systems will adjust signals according to real time data. Automated driverless subway trains will run at short intervals and electronic tickets will be issued via mobile radio.

According to a UN forecast, more people will live in cities than in rural areas by 2007 (see Facts and Forecasts). As a result of this, a number of problems can be expected, says Hartmut Scherer-Winner, a traffic technology consultant at Siemens Corporate Technology (CT). "Whereas some developing countries still need to build up basic infrastructure, such as roads and traffic light systems, cities in Europe, Japan and the U.S. will need to employ telematics solutions in order to use existing infrastructure and transport systems more efficiently," he says. The first steps in this direction have already been taken.

Linking traffic information. In a joint venture with DaimlerChrysler Services, Siemens launched the Traffic Management Center (VMZ) in Berlin in the summer of 2003. The VMZ is viewed as a model for tomorrow’s intelligent traffic and transport system. In addition, negotiations are now under way regarding two similar projects in Germany’s Ruhr District and in Bavaria. At the heart of the VMZ is the SITRAFFIC CONCERT traffic management system from Siemens Industrial Solutions and Services. This sophisticated data-linkage network combines information on urban traffic, parking conditions, construction sites and special events that can affect traffic. The system uses such data to offer constantly updated recommendations via the Internet, cell phone, radio (RDS/TMC) and roadside electronic information billboards.

At the moment, however, traffic planners often don’t have enough information on what’s actually happening on roads. Scherer-Winner therefore emphasizes that more reliable sensor technology holds the key to optimizing traffic analyses. Although Siemens has extensive experience in this area—for example, it has installed coils beneath road pavements—the technology involved has its limits. "For one thing, laying coils is very expensive," says Scherer-Winner. "They also wear out, which means many detector units have to be repaired, and that costs even more money. That’s why I think the trend is moving toward above-ground traffic monitoring using so-called smart sensors. Although these still don’t work as precisely as coils, they’re getting better."

One example of an above-ground traffic sensor is the Traffic Eye Universal measuring station for urban applications. Here, an infrared detector registers the number of vehicles in each lane, as well as their length and speed. Such data is used, for example, to calculate the differences in speed between vehicles traveling on a particular street or road. The greater such differences, the greater the probability that a traffic jam will form. Siemens researchers are also working on new monitoring systems—such as those employing videosensors—that not only show actual traffic situations onscreen at a control station, but also use intelligent image processing systems to recognize critical situations such as congestions or accidents, and then automatically issue warnings (see Pictures of the Future, Spring 2003,  Smart Cameras).

Optimizing Traffic Flows. Nevertheless, even intelligent detectors are merely pieces in a puzzle that has to be put together before a city’s traffic and transport network can be depicted and analyzed. To optimize traffic from such individual data, Siemens developers embedded a system known as MOTION in their SITRAFFIC concept. MOTION automatically ensures the highest possible series of green lights on a given stretch of road.

The system operates in four stages: First it collects data from various measuring stations, which is then used to analyze the traffic situation and create corresponding models. Then it applies these models to generate signal commands for the traffic lights in question. This includes, for example, determining how long red and green phases should last if traffic is to move as smoothly as possible. Finally, the system checks this signaling program against the current traffic situation every five to 15 minutes to determine whether the sequence needs to be updated. If necessary, new control commands are sent online to the traffic light switching systems.

MOTION can also be programmed to give priority to streetcars or buses. This is no easy task, as the system must continue to keep tabs on the overall traffic situation while intervening at individual locations. Failure to do so could lead to disturbances in heavily congested areas, and some areas might even be brought to a standstill. The problem here is that more and more vehicles are now equipped with navigation systems that receive and process information from private service companies. Due to a lack of coordination with public control centers drivers of such vehicles could be directed toward quiet side streets whose traffic lights have been set for long red phases by public systems. This leads to unnecessarily longer driving times.

Siemens researchers intend to remedy this situation, which is why they are participating in the INVENT (Intelligent Traffic and User-Friendly Technology) research initiative of the German Ministry of Education and Research (BMBF). Specifically, they are contributing a project known as Balanced Network for Personal Transportation, which will run until 2005. The program’s goal is to develop an optimized route planner. Such a system would not only choose the fastest route; it would also incorporate, for example, higher priority green-light public control centers into the route plan. To accomplish this, navigation centers will require more information on current traffic and street conditions. The researchers therefore want to supplement stationary monitoring units with so-called floating cars that serve as mobile data collectors. Many late model cars already suit this purpose. Equipped with numerous sensors, such cars not only use GPS to determine vehicle location, they can also provide data on speed, windshield wiper activity, vehicle lights, and braking. Such information can be used to draw conclusions regarding weather conditions and the likelihood of traffic jams. If this data were transmitted anonymously via mobile radio to a traffic management center, it could be processed into individual route recommendations.

Trains every 90 seconds. In addition to the numerous things that can be done to improve personal transportation, Scherer-Winner believes that optimized public transportation systems can provide urban areas with an instrument for combating traffic jams and noise and air pollution. "If local public transport systems are not improved, cities will find it increasingly difficult to cope with traffic congestion," he says. However, to make public transportation more attractive, it will have to become more comfortable and more convenient. In terms of rail transport, this means more frequent service—around the clock if possible.

This, of course, would require more personnel, a factor that worries transport operators, given the generally high wage levels in many European countries. The solution could be automated public transport systems. Instead of service intervals of a minimum of four to five minutes, as required with human drivers, automated trains can safely run at 90 second intervals. Automatic systems can also get trains out of stations more quickly than human drivers can. A fully automated train can also reduce the time needed for starting and braking. On the other hand, such systems require a greater outlay for track safety and control technology.

Back in 1983, Siemens inaugurated the world’s first fully automated train system in Lille, France. Since then, many other automated subway systems have entered service, for example, in Canada, Japan, Great Britain and China. Germany has hesitated in introducing such a system, although automated subway trains were tested in Berlin in the 1980s and ’90s. Now, however, the first fully automated subway line in Germany is set to become operational in Nuremberg in 2006—and it will do so in a manner that will mark a world-first. According to project director Helmut Beismann from Siemens Transportation Systems in Nuremberg/Erlangen, both automated and conventionally driven trains will be operated simultaneously on one line for about two years. Then, in 2007, work will begin on fully automating the entire subway system.

That’s easier said than done, given the fact that two different train and signal control systems operating on the same tracks are involved. Nevertheless, the idea is that the trains, whether automated or not, should run at extremely short intervals. Driverless trains will enter stations one or two minutes after conventional trains, and manually operated trains will run about three or four minutes behind the automated ones.

"The technological achievement here is that two signalling programs have been aligned," Beismann explains. "Nuremberg could therefore become a model for other cities that wish to integrate driverless trains into their subway systems."

Tickets from Your Phone. An Electronic Ticketing pilot project from Siemens Business Services promises greater convenience for public transport passengers. The project is undergoing test operations in and around Plauen, a city near the German, Czech Republic border. Passengers in this area no longer need to purchase bus or train tickets from machines. Instead, they can book a ticket via cell phone.

The system works like this: riders simply conduct a one-time registration procedure with a service center, from which they download a small booking program to any Java- capable cell phone. Users then navigate the corresponding menu to order a virtual ticket, which is stored on a server that only a train or bus conductor can access.

Those who get tired of typing can call a special number and place their orders with a speech-based interactive computer system. During the test phase (February to April, 2004) the ticket price was deducted from the user’s bank account. Later, it will be possible to bill tickets via a user’s phone bill or deduct the costs from a credit or prepaid card.

Checking Ticket Validity Via Mobile Radio. Another project, which is known as intermobilPASS, takes things a step further. Here, passengers don’t even have to purchase a ticket, says project director Patrick Almy of Siemens Transit Telematic Systems, Switzerland. As part of a BMBF program, a new version of a previously tested chip card will undergo a trial run in Dresden, Germany in early 2005. The card was originally evaluated three years ago as part of the EasyRide project in Basel and Geneva, Switzerland. In this system, passengers simply carry the card in a pocket and ride buses or streetcars—without worrying about tickets. A chip on the 3-mm-thick card, which is soon to be reduced to the thickness of a credit card, is activated by a pulse transmitted from the vehicle’s door when the passenger enters. This switches on the card’s standby mode. As soon as the vehicle leaves the station—the motion is registered via GPS—a virtual conductor in the vehicle uses a special antenna to transmit an 868 MHz signal through the interior of the vehicle, reading off the authorization to travel from each chip card.

The system also registers passengers who exit the vehicle. In this case it transmits the associated data via mobile radio to a central control station, where the distance traveled by that particular passenger is calculated. The passenger then receives a bill or the control center deducts the price from a prepaid account. As an alternative to the chip card, Siemens researchers are installing location registration technology in cell phones, thus eliminating the need for the chip cards altogether. It is still unclear when exactly the intermobilPASS will be introduced. "We’re looking at ways to finance further development of the technology," says Almy. "Our ultimate goal is to optimize the technology so that passengers will be able to travel throughout Germany with the chip card or a cell phone—and maybe even all over Europe in ten years."

Rolf Sterbak