Transportation

figure 11: singapore parking guidance system

ing their speed and location information back to Sin- gapore’s Traffic Operations Management Center (Fig- ure 9), enabling it to generate an accurate picture of traffic flow and congestion on Singapore’s roadways from this critical mass of probe data. The arrangement Singapore has with taxi operators is a commercial one. It developed when one of Singapore’s dominant taxi operators decided to enhance their operations with a GPS fleet management and dispatch system, and the Land Transport Authority asked if it could ride on this development to obtain traffic information.¹⁰⁹ Singapore disseminates traffic information via its Expressway Monitoring and Advisory System (EMAS), comprised of variable message signs placed strategically along its expressways. In addition, Singapore purchases air time from radio service providers to transmit traffic updates over the air. Singapore is also starting to im- plement these traffic messaging systems on its arterial roadways.

Singapore is a world leader in electronic road pricing, and has actually had some form of congestion pric- ing scheme in place in its city center since 1975, al- though initially the system was based on license sheets in windscreens and spot-check police enforcement. In 1998, Singapore implemented a fully automated elec- tronic road pricing (ERP) system that uses DSRC with an in-vehicle unit installed in each car that accepts a prepaid stored-value smart card called the “Cashcard.” The cost of using a particular road is automatically deducted from the Cashcard when the vehicle passes an ERP gantry. The system has since been expanded beyond Singapore’s downtown Restricted Zone to its expressway and arterial roadways, and now accepts credit card payment. Singapore’s ERP scheme actually uses traffic speeds as a proxy for congestion. Rates are raised or lowered to achieve traffic optimization along a speed-flow curve, 45 to 65 kmph for expressways and 20 to 30 kmph for arterial roads. In effect, the system uses market signals to manage supply and demand on Singapore’s roadways. Singapore is currently evaluat- ing moving to a next generation ERP system (ERP

II) that would use satellite-based GPS technology to make distance-based congestion charging possible. Singapore believes that converting to GPS-based tech- nology will enable a flexible and more efficient method to manage congestion, and provide opportunities to develop a more intelligent information dissemination and navigation system for drivers.¹¹⁰ LTA estimates
that the economic benefit of time savings due to short- er delays on expressways, largely achieved through use of congestion charging, amounts to at least $40 million annually in Singapore.¹¹¹

Singapore has made public transportation a more at- tractive option for commuters by installing real-time bus arrival panels in January 2008 at almost all bus stops throughout the country (Figure 10).¹¹² As of March 2010, LTA will begin disseminating real-time bus arrival information to all bus stops island-wide via various mobile platforms. In July 2008, LTA launched a Public Transport Journey planner with basic map features that advises commuters on optimal public transport travel routes from origin to destination. This will be followed by an Integrated Multi-Modal Travel Information System (IMTI), which will provide com- muters with comprehensive travel information on dif- ferent platforms such as the mobile phone and the In- ternet (via GRPS, WAP, and WIFI.)¹¹³

In April 2008, Singapore launched a Parking Guid- ance System (Figure 11), consisting of roadside variable messaging signs, which alerts drivers to the location of public parking locations throughout the city and how many spots are available at each location. Singapore is now expanding this service country-wide.

Singapore’s long-term ITS plans include advanced tele- matics that will bring location-based services and traf- fic information to commuters through in-vehicle de- vices, and advanced congestion management systems that will include both targeted and variable user road- charging schemes. Singapore is at the cutting edge of predictive traffic flow modeling based on using historic and real-time traffic data.