Athens was praised for hosting one of the most successful Olympic Games to date back in 2004. The success of the project was not least due to the scrupulous attention to detail and security that hallmarks such international events. The Greeks went over their budget, spending in excess of $7bn, of which security accounted for $2bn.
One of the long-term advantages is that the City of Athens has gained some very important state-of-the-art infrastructure, which is still paying dividends today. The most important of these is its traffic management system.
The system was first planned in 2002 and was completed on time for the summer 2004 deadline, costing an estimated â‚¬255m to design, construct and implement. The system was financed jointly by the Greek Government and the City of Athens.
The traffic management system contains a number of different components that were supplied and integrated into the system by the perceived best contractors worldwide.
These included: Image Sensing Systems Inc, ATS Traffic Systems, Econolite (joint manufacturers of the Autoscope), Gedas, Geotopos AG, Zeppelin Luftschifftechnik GmbH, the German Aerospace Center (DLR), the Bosch subsidiary Blaupunkt, the Fraunhofer Institute IP, the Technical University of Crete, SAIC Consortium (Siemens AG, General Dynamics Corporation, Honeywell International, Elbit Systems and Nokia) and Atos Origins.
TRAFFIC MANAGEMENT SYSTEM (TMS)
The traffic management system (TMS) central software is Siemens SI-Traffic Concert. The system is operated from two control centres (to allow for the event of one control centre failing) fed with data from a variety of sources including close circuit television cameras, traffic signals, Autoscope video-detection cameras, ground loop detectors, speed radar devices and security personnel and traffic police on the ground. The system can analyse and process the information it receives and then display traffic conditions using a graphic user interface (GUI).
The decision-making algorithms programmed into the TMS can then determine how best to handle the problems. The system can act automatically via variable message signs on the road side, by adjusting the phase and continuity of traffic signals (by rerouting traffic around obstructions or temporary bottlenecks) and by alerting traffic police on the scene. In this way Athens famous grid-lock traffic jams were avoided during the Olympics and are hopefully a thing of the dim and distant past.
VIDEO VEHICLE DETECTION SYSTEMS
75 Autoscope SOLO Pro NC Video Vehicle Detection Systems (vision processors for video vehicle detection systems) are integrated into Athens’ traffic management system. The systems were equipped with high-resolution, low visibility AIS Cameras and can detect speed, vehicle density, vehicle types, stopped vehicles, traffic incidents and vehicles travelling the wrong way.
The Autoscope cameras are mounted on 14m-high steel poles and the information they receive is relayed back to the two control centres via a fibre optic cable network. The AIS Camera is a durable, high-resolution video traffic camera with a built-in zoom lens and colour imager with high sensitivity to ensure accurate vehicle detection at night. It minimises streaking and blooming from bright light sources that could adversely affect detection performance.
An adjustable weather shield minimises rain, sleet and snow contact on the faceplate. It also reduces glare, which improves video contrast and can operate in a temperature range from -40Â°C to +60Â°C.
TRAFFIC DATA INPUT
The control centres receive information from 200 closed-circuit TV cameras and over 700 in-ground loop detectors. In addition there are the 75 specialised Autoscope systems. The system controls 1,500 traffic signals in the greater Athens area and 24 variable messaging signs. The system is also integrated with the command centre established for Olympic security systems, a secure digital trunk radio network and geographical information systems (making use of GPS).
These systems were developed by a consortium led by San Diego-based Science Applications International Corp (SAIC) and cost about $312m. They gather images and audio data from an electronic web of over 1,000 high-resolution and infrared cameras, 12 patrol boats, 4,000 vehicles, nine helicopters, a sensor-laden Zeppelin NT (equipped with high resolution cameras from the German Aerospace centre and able to act as a fail safe) and four mobile command centres. Material from the closed circuit cameras is kept for seven days so that incidents can be analysed. Analysis is enabled by software from London-based Autonomy Corp.
FLOATING CAR DATA TECHNOLOGY
Floating Car Data (FCD) technology allows official vehicles such as police cars or emergency services to act as sensors to allow the continuous, real-time recording of a current traffic situation and to form the core of traffic data acquisition. The system was originally trialled with 50 vehicles in the Frankfurt region and adopted in Athens for the Olympic Games. Developed by the Fraunhofer Institute, Gedas and Blaupunkt, the technology is optimised for use in cities.
City-FCD is a state-of-the-art system that was integrated into the Athens traffic management system in summer 2004 to aid in the movement of fleets of Olympic vehicles through busy traffic situations. It works in conjunction with the aerial monitoring of the airship above the city, which could function independently if required.
If a vehicle equipped with ‘City-FCD’ reports a traffic jam, one of the operators in the traffic control centre will direct the airship to the area to monitor the traffic situation.
The high resolution of the special cameras allows a grid to be placed over the blocked roads; this makes it easier to determine average speeds and permanently assess the traffic conditions.
Traffic data from the airship are transmitted via the emergency cellular network to the traffic control centre where it is combined with the ‘City-FCD’ data. The mixture of data can then be analysed and used to determine the actual traffic situation. This is then used as a basis for the decisions of the traffic and safety authorities.
HOW FCD WORKS
City-FCD is based purely on a combination of storage media, cellular communication and vehicle positioning. Special algorithms, which were developed by Gedas together with the Fraunhofer Institute, allow the precise description of a traffic jam along with a prognosis of its ‘behaviour’.
The main traffic network in Athens is digitally recorded. This is performed as follows: the degrees of latitude and longitude are digitally locked into the memory of tracking devices, such as Blaupunkt’s Fleetcommander or the Nokia Communicator.
A grid with predefined roads and junctions is placed over the entire region. The vehicles then act as mobile sensors within this grid. Data collection begins whenever a vehicle from this sample fleet enters one of the grid sections, and the travel time data is transmitted to the telematics center via Short Message Service (SMS) as soon as the vehicle leaves the section. The current traffic flow situation can be immediately determined based on the data passed on by several different vehicles.