Urban traffic management system assignment 2


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Urban traffic management system assignment 2

  1. 1. Supervisor name: Prof. Ir. Dr. Riza Atiq Abdullah Done by: Mohanad jaafar talib – p71085 URBAN TRAFFIC MANAGEMENT SYSTEM
  2. 2. MAXBAND • Overview • MAXBAND model of bandwidth optimization assumes that all the vehicles have the same speed. But there is traffic flow dispersion because of different vehicle performance. Traffic flow dispersion has been described by Normal Distribution and Geometric Distribution. MAXBAND is the only operational traffic signal program that allows progression bandwidth optimization in multi arterial , closed-loop traffic signal networks. The program formulates the problem as a mixed integer linear program and is capable of optimizing network-wide cycle length, signal offsets, and signal phasing sequences. However , hours of computer time may be required to optimize a medium-sized network problem , even on a mainframe computer. This computational inefficiency of MAXBAND makes it impractical for use by the traffic engineering community.
  3. 3. MAXBAND • Features and Evaluation • MAXBAND has two heuristic methods efficiently optimize network signal timingproblems modeled. The experimental results demonstrate that these heuristic methodsproduce tremendous savings in the computer time required to solve optimizationproblems in traffic network signal timing. In addition, computational benefits areachieved by explicitly modeling one-way arterials in a network rather than as two-wayarterials.In MAXBAND, vehicles are loaded on an arterial and traffic signals on that arterial arecoordinated to optimize a performance criterion, which often relates to the number of stops.
  4. 4. SCATS SYSTEM • Overview • The Sydney Coordinated Adaptive Traffic System (SCATS) is an innovativecomputerized traffic management system developed and maintained by roads andmaritime services (RMS) .SCATS has beenfaced with the need to implement a largearea traffic control system in Sydney and mindful of the problems of "fixed-time"systems, the NSW Department of Main Roads (now Roads and Maritime Services)embarked on the development of a traffic responsive system in the early 1970s whenmini-computers became available at a cost comparable to purpose-built hardware. Aldridge Traffic Controllers (ATC) are an RTA authorized Distributor of the world leading SCATS™ Urban Traffic Management Control (UTMC) System. • Many years of research, testing and software coding have been invested in thedevelopment of SCATS. As of February 2012, SCATS has been distributed to 258 cities in 26 countries worldwide controlling more than 34,943 intersections worldwide,including installations in Australia, Bangladesh, Brazil, Brunei, Chile, China, Ecuador,Fiji, Indonesia, Iran, Ireland, Israel, Jordan, Laos, Malaysia, Mexico, New Zealand,Philippines, Poland, Qatar, Singapore, South Africa, Thailand, USA and Vietnam.
  5. 5. SCATS SYSTEM • Features and Evaluation • SCATS uses anticipatory and adaptive techniques to increase the efficiency of the road network by minimizing the overall number of vehicular stops and delay .The primary purpose of the SCATS system is to maximize the throughput of a roadway by controlling queue formation . SCATS system has the ability to change the signal phasing , timing stratagems and the signal coordination within a network to alleviatecongestion by automatically adjusting the signal parameters according to real timetraffic demand . • SCATS operates at two basic levels known as the “upper level” which involves offset plan selection and the “lower level” which involves optimization of junction parameters. The upper level generates offset plans by time of day from historic data while the lower junction level optimizes green splits,cycle times and offsets between signalised junctions using an increamental feedback processs based largely on detectors situatedat the stop lines . It calculates green splits based on the flow in the previous cycle andso is not fully responsive to unpredictable arrival flows .SCATS is basically a modular system largely run by regional computers capable of handling a large number of intersections with significient intelligence within localcontrollers and may be used to improve management function by central computer .SCATS charactarised by the network manager has a more direct involvement thanother systems in setting up the system .
  6. 6. SCATS SYSTEM • Application • Most of Highway operator in Malaysia using SCATS to control their traffic Lights inurban area. These very popular SCATS is an area wide traffic management system thatoperates under the Windows environment. It controls the cycle time, green splits andoffsets for traffic control intersections and mid - block pedestrian crossings. With theinclusion of vehicle detectors, it can adaptively modify these values to optimize theoperation to suit the prevailing traffic. Alternatively, it can manage intersections in fixed-time mode where it can change plans by time of day, day of week. It is designed tocoordinate traffic signals for networks or for arterial roads. • Intersection connections to a regional traffic control computer can be permanent or maybe on- demand using dial-in or dial-out facilities. Each regional computer can manage upto 250 intersections. A SCATS system can have up to 64 regional computers.Monitoring is provided by a graphical user interface. Up to 100 users can connect to aSCATS central manager at the same time. Up to 30 users can connect to a singleregional computer simultaneously. Performance monitoring, alarm condition notificationand data configuration facilities are included. SCATS automatically collect alarm andevent information, operational and performance data and historical data. SCATSoperate automatically but operation intervention is provided for use in emergencies.
  7. 7. SCATS SYSTEM • Benefit • The popular concept is that coordinating traffic signals is simply to provide green- waveprogression whereby a motorist travelling along a road receives successive greensignals. While this is one of the aims, the principal purpose of the control system is tominimize overall stops and delay and, when traffic demand is at or near the capacity of the system, to maximize that capacity (throughput) and minimize the possibility of traffic jams by controlling the formation of queues. Can be upgraded or expanded to meetchanging requirements, other applications can be integrated into the system andprovides details/reports of traffic flows for other planning purposes. SCATS enable ahierarchical system of fall back operation in the event of temporary communicationsfailure. Such equipment faults are monitored by the system
  8. 8. SCOOT • overview • SCOOT (Split Cycle Offset Optimisation Technique) was developed in the UnitedKingdom by Transport Research Laboratory (TRL) . SCOOT has proved to be aneffective and efficient tool for managing traffic on signalised road networks and is nowused in over 130 towns and cities in UK and overseas world wide.It coordinates the operation of all the traffic signals in an area to give good progressionto vehicles through the network. Any adaptive traffic control system relies upon gooddetection of the current conditions in real-time to allow a quick and effective response toany changes in the current traffic situation. SCOOTS has a substantial data base facilityfor storing , manipulating and presenting traffic data including flows , journey times andqueues . . It has three optimisation procedures by which it adjusts signal timings theseare the cycle time, green splits, and offsets , each optimised using a differenetprocedure at different frequences
  9. 9. SCOOT • Features and Evaluation • SCOOT uses detectors at the upstream end of links to measure demand and cyclic flowing real time and the operation has considerable flexibility to override values and set parameters for different regions and different times. Theoretically, the benefits of SCOOT should be highest when traffic flow is heavy, complex and unpredictable. SCOOT can prevent congestion by delaying it long enough to permit a short duration overload to be completely overcome .SCOOT evaluates the advisability of altering the cycle offset at the intersection with respect to the master schedule by four seconds in either direction. Every five minutes it explores the option of changing the cycle length for individual subareas, usually consisting of three to four intersections. SCOOT makes about 10,000 decisions per hour for every 100 intersection in the system all made by central computer. When SCOOT detects that saturation levels are unacceptable , it reacts with actions at distance. SCOOT naturally reduces vehicle emissions by reducing delays and congestion within the network and can be set to adjust the optimization of the signal timings to minimize emissions , also to provide estimations of harmful emissions within the controlled area.
  10. 10. SCOOT • Application • Information on the physical layout of the road network and how the traffic signals control the individual traffic streams are stored in the SCOOT database. Any adaptive traffic control system relies upon good detection of the current conditions in real-time to allow quick and effective response to any changes in the current traffic situation. SCOOT detects vehicles at the start of each approach to every controlled Intersection. It models the progression of the traffic from the detector through the stop line, taking due account of the state of the signals and any consequent Queues. The information from the models used to optimize the signals to minimize the network delay. The operation of the SCOOT model is summarized in the diagram above. SCOOT obtains information on traffic flows from detectors. As an adaptive system, SCOOT depends on good traffic data so that it can respond to changes in flow. Detectors are normally required on every link. Their location is important and they are usually positioned at the upstream end of the approach link. Inductive loops are normally used, but other methods are also available. When vehicles pass the detector, SCOOT receives the information and converts the data into its internal units and uses them to construct "Cyclic flow profiles • for each link. The sample profile shown in the diagram is color coded green and red according to the state of the traffic signals when the vehicles will arrive at the stop line at normal cruise speed. Vehicles are modeled down the link at cruise speed and join the back of the queue (if present). During the green, vehicles discharge from the stop line at the validated saturation flow rate. The data from the model is then used by SCOOT in three optimizers which are continuously adapting three key traffic control parameters - the amount of green for each approach (Split), the time between adjacent signals (Offset) and the time allowed for all approaches to a signaled intersection (Cycle time). These three optimizers aroused to continuously adapt these parameters for all intersections in the SCOOT controlled area, minimizing wasted green time at intersections and reducing stops and delays by synchronizing adjacent sets of signals. This means that signal timings evolves the traffic situation changes without any of the harmful disruption caused by changing fixed time plans on more traditional urban traffic control systems.
  11. 11. SCOOT • Benefit • Throughout its life SCOOT has been enhanced, particularly to offer an ever wider range of traffic management tools. The traffic manager has many tools available within SCOOT to manage traffic and meet local policy objectives SCOOT detectors are positioned where they will detect queues that are in danger of blocking upstream junctions and causing congestion to spread through the network SCOOT w ill continuously monitor the sensitive area and smoothly impose restraint to hold traffic in the specified areas when necessary. SCOOT naturally reduces vehicle emissions by reducing delays and congestion within the network. In addition it can be set to adjust the optimization of the signal timings to minimize emissions and also provide estimations of harmful emissions within the controlled area.
  12. 12. ITACA • Overview • ITACA ( Intelligent Traffic Area Control Agent) has an adaptive subsystem that operates with a traffic model and produces cycle split and offset times for a centralized area of traffic control. These times minimize delay and stops of traffic moving in the area.ITACA provides real time urban traffic control by computing the best solution for every intersection and continuously adapting signal sequences to match traffic demand. The system produces small and frequent changes in traffic control parameters that smoothly adapt the traffic control plan to evolving changes in traffic demand. In this way, the negative effects on the network that otherwise would be caused by plan changes such as, flow disturbances and time delays in establishing flow are avoided.ITACA is an integral solution for traffic management in urban areas, providing the capability to control traffic intelligently in real-time, while constantly adapting to changing traffic needs. This system will help improve the quality of life for the more than 2.5million inhabitants in the Cities worldwide , by increasing traffic flow efficiency, while reducing congestion and air pollution.
  13. 13. ITACA • Features and Evaluation • ITACA is occupying of enhancement to every 5 seconds on carry on a time of collection and processing to the transportation data. All produces the corresponding parameter to each street intersection to distinguish the treatment . Each several cycles have carried on a time of adjustment according to the system computed result to each region cyclical length , namely cyclical adjustment. Each cycle carries on the assignment adjustment according to the system computed result to each street intersection different green light time , namely the green letter compares the adjustment. Each cycle starts the time according to the system computed result to each street intersection cycle to carry on the adjustment, namely phase adjustment • ITACA is the intellectualized auto-adapted transportation control system ,this system by the real- time control way work and can most greatly expand to more than 4500 street intersections controls by center control level which is composed by a control server and the client. The center control level installs ITACA software ,realizes the communication function ,the database handling dbh function , the software starts and software stops the function .Through uses the auto-adapted traffic signal control system, may reduce the transportation in the existing path to support stops up with the driving delays, reduces the traffic accident, the formation rate and the mortality rate, simultaneously may cause the energy the consumption reduction, and reduces the pollution degree.
  14. 14. ITACA • Application • As example Currently there are 128 number of junctions that had been installed with traffic signals in Putrajaya. There are junctions that are fully operated, while some were operated in ‘Flashing Amber' and a few others are still under construction (ducting and cabling works in progress). Refer Drawing1. An the latest news in Malaysia for greater KL done by Special Task Force to Facilitate Business (Pemudah) said the initiatives included enforcing the Towing of vehicles of traffic offenders and implementing traffic monitoring Using Sydney’s Coordinated Area Traffic System (SCATS) and Intelligent Traffic Adaptive Control Area (ITACA) to further enhance traffic flow. Is opposite to the traditional system, the ITACA occupying of enhancement to Every 5 seconds on carryon a time of collection and processing to the Transportation data. All produces the corresponding parameter to each street intersection to distinguish the treatment. (In system has each street Intersection in entire network accurate position, therefore system all collects Information from each street intersection all neighbors street intersection). Each several cycles on have carried on a time of adjustment according to the System computed result to each stature region cyclical length, namely cyclical Adjustment. Each cycle all carries on the assignment adjustment according to the system Computed result to each street intersection different green light time, namely the green letter compares the adjustment. Each cycle all starts the time According to the system computed result to each street intersection cycle to carry on the adjustment namely phase adjustment. May act according to the Transportation expert's experience, carries on the optimization to the system. Under , will introduce the ITACA system from following several aspects.
  15. 15. ITACA • Benefit • Has included the auto-adapted traffic signal control system in the existing new technicalmethod, it is the intelligent transportation control system core. Uses the benefit whichthe advanced auto- adapted traffic signal control system produces to be most obvious.Through uses the auto-adapted traffic signal control system, may reduce thetransportation in the existing path to support stops up with the driving delays, reducesthe traffic accident the formation rate and the mortality rate, simultaneously may causethe energy the consumption reduction, reduces the pollution degree. Talent Traffic yTransported (original Since Traffics) took is engaged in the transportation control for along time the well-known company and the Spanish Oviedo university cooperation, insummarizes in the foundation Which the predecessor an experience, developed in 1990has developed set of auto-adapted traffic signals control system ITACA (IntelligentTraffic Adaptive Control of Areas ) the system. This system is based on the coil real-time Collection data, in the computer module the simulation real-time Optimizationmovement, and real-time issues the transportation control Command, achieves the besttransportation control effect the advanced system. The ITACA system in the world manycities success movement, the Performance is outstanding, in domestic city and so onBeijing, Wuhan has the Small scale application, in the near future also in other citylarge-scale
  16. 16. RONDO • Overview • RONDO (Rolling horizon based Dynamic Optimization of signal control) has been developed that enables dynamic optimization of signal control parameters according to traffic flow changes. A rolling-horizon algorithm is selected as an optimization method. RONDO can apply to diverse traffic conditions from under-saturated to over- saturated . RONDO also considers reducing traffic accidents. Some simulation tests have been executed for the first step of evaluation of the system. Simulation experiments results show that the system can manage unstable traffic flow well. It also shows the possible application of the system.
  17. 17. RONDO • Features and Evaluations • RONDO has designed to optimize the signal timings of each signal every severalseconds according to the predicted cost expressed by the signal control performancefunction with traffic efficiency indexes such as delay and stop number, which areestimated based on the prediction of traffic flow changes in several minutes.Consequently the signal timings are continuously updated. That enables RONDO tomanage the sudden changes of traffic flow. • RONDO control system has the following three features: • [1] Through terminal-terminal communication, oncoming traffic information is obtainedfrom signal controllers at upstream intersections; thereby the traffic flow approaching agiven intersection is predicted for time spans from the present to several minutesahead • .[2] Simulations are calculated for very short intervals for individual intelligent trafficcontrollers to determine the optimal green time that minimizes vehicle delay (wait timeat stoplight). • [3] Two control modes are possible: a hybrid type in which signal control is performed incoordination with central controller, and an autonomous type in which traffic signalsperform independently while coordinating with neighboring traffic controllers.
  18. 18. RONDO • Application • Rondo uses a feedback loop to govern the behavior of traffic in the network core. It manages the flows that originate and terminate between various PoPs (Points of Presence) in the network by directing these flows into the multiple pathways that are created using MPLS Label Switched Paths. These LSPs serve as conduits through the network that are unaffected by the local optimization strategy of shortest path routing. Rather, Rondo optimizes performance based on global traffic considerations in the network.
  19. 19. RONDO • System Components • Rondo is composed of the major parts. In the remainder of this paper, we will describe each element with emphasis on the data collection subsystem and the analysis engine. • 1) Physical Network • The experimental network is a set of 10 MPLS-enabled counters and Interconnections patterned after a much-scaled down representation of a major Service provider’s network backbone as depicted on their web site. We note that the provider has 2500Pops worldwide so our model has only rough equivalence to reality. However, even with only ten routers, our network exhibits complex and often fascinating behaviors. Routers are connected with 10-megabit links, which makes possible the creation of realistic overload Conditions. Each router models a Pop (Point of Presence) on the network where customer nodes are attached. In Rondo, each node attached to a Pop is a PC that sends and receives packets. The network uses a combination of Cisco® 3620 and3640 series routers. The Release of Cisco’s IOS (Internet Operating System) available on our routers Allows only destination- based selection of MPLS tunnels. Upgrades will ultimo- Cisco is a registered trademark of Cisco Systems, Inc. mutely allow selection of the tunnels based on other parameters in the IP packet. • 2)Programmable Load Generators and Loading Strategy • We use a collection of PCs programmed [1] to generate time-varying loads Similar to those expected in an operational network. Background network Traffic on the network inconstant in time and is generated by commercially available packet generators. Loads are carefully crafted to cause a buildup of Congestion that does not have an overall steady state solution, and are designed to stress the given physical topology.
  20. 20. RONDO • 3) Data-Collection System • The data-collection system uses a variety of devices and techniques to monitor the conditions in the network. These include both active and passive Methodologies that capture such characteristics as throughput, loss, delay and jitter. Data collection, a key part of Rondo, uses an extensible architecture to provide rapid processing of data under time constraints for its collection, reduction and transmission. Data flow from the network probes through the Collection system to the analysis engine with little latency and to archival storage at a lower priority. Data are retained in a database system for other Applications such as service-level management that do not require rapid data Processing. We describe this part of the system in detail below. • 4)Data Model and Database • Rondo uses the database for a variety of classes of information including Physical analogical network topology, configuration information and archived measurement data. The algorithms, displays and other components are driven by the information described by this model, and as such, the Organization of this model is crucial to the effectiveness of Rondo. The model, which is important for other applications, is realized in a relational database. The most important function of the database is to hold the state of the network topology, which changes as the system reroutes LSPs to alleviate congestion. The analysis and reroute engine periodically updates the topology as the network is reconfigured.
  21. 21. RONDO • 5) Analysis and Rerouting Engine • This element of the system contains techniques for detecting congestion in a Network and altering the existing traffic flows to eliminate an overload condition. The engine is designed to focus on more than link utilization, which is the most basic metric of network performance. Utilization indicates the level of activity between network elements and is often viewed as a measure of network congestion. This view is too simple when one considers the classes of traffic that flow over an IP network. High utilization of a link is one form of congestion, but others might include excessive delay, jitter or high packetl oss, all of which could happen at relatively low levels of link utilization. These are measures of congestion that seriously affect proposed services in Next-generation IP networks, including voice and video. The engine is Designed use any measurable quantity as an indication of a network problem That needs correction. • 6)MPLS Configuration and Control • Rondo relies on MPLS to form explicit paths through the core network. Explicit path sallow precise control over the placement of traffic flows within the routed domain of Rondo. All traffic in Rondo flows through explicitly routed MPLS tunnels, which specify each node along a path from the ingress to egress routers. The network configuration is initially optimal in the sense that all tunnels travel via the shortest path in the network. Once established, packets enter the MPLS tunnels as a function of their destination address and are delivered to the egress router. Rondo thus uses MPLS as a mechanism for packet forwarding that is not directly aware of quality of service. Mixing packets with different levels of quality of service in an LSP is possible though but limits the effectiveness of available controls. Once the initial explicit paths are established, the analysis and reroute engine operates to reroute packets through a path established by anew MPLS tunnel, which may no longer be the shortest path. This action currently takes place via IOS commands that are issued from the controller. When MPLS traffic-engineering MIBs become available, the controller will use SNMP to establish the new routes.
  22. 22. RONDO • B.System Operation • The analysis and rerouting engine is in overall control of the system. The engine communicates with the data collection system to establish a schedule of network measurements. As the data collection system takes each measurement, it notifies the analysis and rerouting engine of the presence of new data. The engine combines the new data with the current system configuration and previous data to decide on the appropriateness of rerouting an MPLS tunnel. If a move is appropriate, the analysis engine reconfigures the network through the LSP configuration control and updates the network state in the database. As we discuss in the following, the route of the newMPLS tunnel does not necessarily preserve overall network optimality. Rather our goalies to reroute traffic as quickly as possible to minimize the congestion at the expense of achieving a theoretical optimum over the whole network. Global optimization might imply moving many or even all the routes in the network. The strategy in Rondo is to move from one to a few MPLS tunnels over a period of a few minutes with minimal disruption to network traffic
  23. 23. UTOPIA • Overview • UTOPIA (Urban Traffic Optimization by Integrated Automation) /SPOT (System for Priority and Optimization of Traffic) is the world’s most advanced adaptive traffic control system and It ensures that optimal traffic control strategies are applied during all traffic . UTOPIA-SPOT is an UTC system that produces co-ordination within an area without neither a common nor a fixed cycle time for each intersection. UTOPIA Spot helps to reduce congestion and traffic pollution in urban areas as it leads to smoother flows of traffic even at peak times. UTOPIA Spot is installed in major cities in Scandinavia, such as Oslo, Trondheim, Copenhagen and it is now used in several cities in Italy and also in the Netherlands, USA, Norway, Finland and Denmark. • UTOPIA Urban Traffic Control System offers a wide range of strategies designed to suit any road network. In the fully adaptive mode, it constantly monitors and forecasts the traffic status and optimizes the control strategy according to flow efficiency and/or environmental criteria. This gives high performance even with unpredictable traffic conditions.
  24. 24. UTOPIA • Features and Evaluation • UTOPIA/SPOT aims to minimize the total time lost by private vehicles during their trips, subject to the constraint that public vehicles to be prioritized shall not be stopped at signalized intersections. This is carried out by optimizing a cost function depending upon various elements including: vehicle delays and stops, delays to public transport; and deviation from the reference plan and previous signal settings. The optimization is carried out at two levels: local and network. At the local level, the controller determines the signal settings by optimizing a cost function adapted to the current intersection traffic situation.
  25. 25. UTOPIA • Application • The power of UTOPIA is prediction. UTOPIA estimates how the traffic Situation will develop and calculates the best possible strategy. The ‘best Strategy’ is based on a so- called ‘cost function’. The cost function weighs issues such as delay time, the number of stops and specific priority Requirements. Taking into account the effect on adjacent intersections, the Distributed control is optimized for each intersection in the network. All intersections communicate the expected traffic flow to neighboring intersections, allowing for a long prediction horizon.
  26. 26. UTOPIA • Benefit • • Keeps the flow going. • • Manages timely public transport; • • Fully adaptive, adjusts to the traffic situation. • • Realizes strategic traffic policy objectives; • • Dynamic priority levels for public transport vehicles; • • Tuned and tested in lab situation before installation on-site; • • Open communication infrastructure
  27. 27. THANK YOU
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