TRANSPORT SYSTEMS TELEM ATICS TST'02 T R A N SP O R T z.45, nr kol. 1570 Z E SZ Y T Y N A U K O W E II INTERNATIONAL CONFERENCE________________ PO L IT EC H N IK I ŚLĄ SKIEJ 2002
traffic control in the cities, dispatchers systems K atarzyna T R Z A S K A 1
DISPATCHER’S CONTROL IN THE CITIES - MAIN DIRECTIONS OF DEVELOPMENT
This paper approaches the basic issues related with the increased traffic in the cities, and presents methods o f their solution using telematic systems. The author intends to draw special attention to the systems giving a priority role of the public transportation, constituting one o f the more important elements o f sustainable development in the cities.
STEROW ANIE DYSPOZYTORSKIE W MIASTACH - GŁÓWNE KIERUNKI ROZWOJU
Tematem referatu jest przybliżenie podstawowych problemów związanych ze wzrostem ruchu w miastach oraz przedstawienie sposobów ich rozwiązania przy pomocy systemów telematycznych.
Szczególną rolę zwrócono na systemy dające priorytet środkom komunikacji zbiorowej, będące jednym z ważniejszych elementów polityki zrównoważonego rozwoju w miastach.
1. IN TR O D U C TIO N
As a resu lt o f m otorization and changes in the u se rs’ preferences at the end o f the eighties o f the last century, a process o f deterioration o f city transport in P oland has occurred.
T his process is hard to stop [6]. T his is expressed m ainly by the follow ing phenom ena:
reduction o f central and local governm ent expenses for urban transport, depreciation o f the rolling stock, increased prices o f tickets, reduced frequency o f travel and transport speed o f vehicles. A ccording to GUS (R P ’s S tatistical A nnual o f 1998 and earlier) the total num ber o f passengers transported by the urban transport com panies dropped from 9,1 billion in 1986 to 5,2 billion in 1998. T he process o f p assen g ers’ outflow is still progressing (although at a low er rate) especially in the sm all and m edium -sized tow ns, w ith tendency to stabilization in the large cities.
In the E uropean countries, sim ilarly, as in P oland, the public transport underw ent a significant drop in the area o f passenger transport, but this process already started in late sixties [6]. T h at is understood as a consequence o f econom ical grow th (and consequently increased w ealth) giving the citizens access to the alternative and strongly com petitive transport m eans, nam ely passenger cars. T h at is also an effect o f stagnation in the quality o f public transport services. “ O utflow ” o f the users to the private cars system atically contributes
1 Faculty o f Transport, Silesian University o f Technology, Krasińskiego 8, 40-019 Katowice, Poland ktrzaska@polsl.katowice.pl
288 K atarzyna TR Z A SK A in crow ding o f streets and results in m any disadvantages related w ith this situation (noise, flue gases, accidents, and destruction o f the landscape).
In the developed E uropean C ountries S tate and local authorities responsible for the condition o f transport, use now every effo rt to raise the quality o f p ublic transport services.
T his is caused by a need to conserve the present num ber o f custom ers and attract new ones, as w ell as trying to convince the passenger ca rs’ users to return to the public transport.
2. B A S IC A REA S O F A P P L IC A T IO N FO R T R A N SP O R T A T IO N T E L EM A T IC S IN T H E CITIES
T he application areas for transport telem atics in the cities m ay be divided into five basic groups [4].
a) U rban T raffic C ontrol:
T h ese are system s w hose basic purpose is to im prove safety and flow o f traffic in the streets. T h ese traffic control system s operate on the basis o f observation o f the traffic courses, road and w eather conditions. T he control is realized and based upon the data obtained from these observations.
b) P ublic T ransportation M anagem ent / T ransport Services w ith D em and V ariable in Tim e:
T he telem atics enters also into such application areas as: ticket distribution system s, public transport fees, and inform ation for passengers. E fficient operation o f these system s is an indispensable factor for enhancing the quality o f the public transport services.
c) Inform ation and C ontrol U sing V ariable T ran sp o rt Signs [1]:
V ariable T ran sp o rt Signs serve m ainly the purpose o f forw arding inform ation to the drivers and p ublic transport passengers. T hey considerably im prove the urban traffic control through dynam ic w arnings about bottlenecks o r road accidents, inform ing about alternative routes or delivering parking inform ation.
d) C urrent Inform ation for P assengers:
E stablishing a sim ple and reliable traffic inform ation system for passengers is one o f the basic elem ents im proving quality o f the public transport services. T he passenger should be provided on a current basis w ith inform ation concerning tim e o f travel, its target and cost. F requently for this purpose V ariable T ransport Signs are used.
e) D em and M anagem ent:
T elem atics enables m ore selective and efficient traffic control by co ntrolling the entry o f vehicles to certain areas and electronic charging system s.
3. A D V A N T A G E S A R ISIN G FR O M U SE O F TE L EM A T IC S IN T H E CITIES
Im plem entation o f telem atics system s in the cities results in a considerable reduction o f road accidents (thus increasing the safety o f road traffic). It is m ainly related w ith a possibility o f v ehicle speed m anagem ent as the vehicle m ovem ent and d riv er’s behavior m onitoring. As it w as show n in th e tests perform ed during realization o f p ilo t projects in telem atics, safety was increasing even by 30% . A nother advantage is a significant grow th in the transport netw ork capacity (not only in the public, but also in the individual transport area), and
D isp a tch e r’s control in the cities - m ain directions o f developm ent 289 reduction o f bottlenecks. Rem oval o f the bottlenecks on the roads entails also savings in tim e, fuel, b etter use o f infrastructure, and transport cost in broad m eaning o f this w ord. B esides we have to also m ention im provem ent o f travelers’ needs m anagem ent, such as parking and its organization, charges in the public transport, and m anagem ent o f entrance to certain areas.
A nd im portant and increasingly frequently advantage o f im plem entation o f telem atic systems is im provem ent o f environm ent conditions. C ontam ination o f natural environm ent resulting from m otorization developm ent is an issue o f considerable im portance not only in the W estern E uropean countries.
T hus, it arises a need to im plem ent such changes to the traffic policy that are likely to ensure an efficient environm ent protection. T elem atics, featuring possibility o f integration and coordination o f various transport m eans, may ensure increased ease o f travel (reliability and speed o f travel). U tilization o f telem atic solutions results also in reduced operating costs, thus im proving econom ical effects.
4. IN STA N C ES O F T R A N SP O R T T E L EM A T IC SYSTEM S IN T H E E U R O PE A N CITIES
4.1. INTEGRATED TRAFFIC CONTROL SYSTEM (IRTE)
In 1992 the city o f T urin started realization o f a large-scale telem atic p roject called 5T (Telem atic T echnologies for T ransport and T raffic in T urin). T his project was established w ithin a Q uartet program and w as financed by the E uropean U nion and Italian M inistry o f E n vironm ent P rotection funds.
T h is system constitutes an integrated solution connecting together 9 com ponent subsystem s;
they are as follow [8]:
a) U rban Supervision System -
It integrates all com ponent subsystem s, supervises their operation and takes basic decisions about general strategy o f operation o f the entire system . All subsystem s operate based upon this strategy, in its individual operational strategies taking into account decisions o f the supervision.
b) U rban T raffic C ontrol -
It is a subsystem m anaging the operation o f the light signals o ver the entire area covered by the project. Its m ain task is dynam ic control o f the traffic on the traffic lights intersections level, based upon local traffic m easurem ent. T his subsystem is also responsible for giving priority to the public transport vehicles at these points.
c) P ublic T ran sp o rt M anagem ent -
It m anages and m onitors on a cu rrent basis the operation o f all the p u blic transport vehicles w orking w ithin the system . In addition, this subsystem oversees the operation o f inform ation boards providing inform ation to the travelers w aiting on the stops, as w ell as th e onboard devices inform ing about the nex t stop and those counting the n u m b er o f passengers.
d) R eduction o f E nvironm ental Im pact -
It uses the w eather forecast and data collected from 11 pollution m easurem ent stations and m akes them available to the U rban S upervision System that uses them to take decisions in accordance w ith the requirem ents resulting from the needs to environm ent protection.
290 K atarzyna T R Z A SK A
e) Parking M anagem ent -
M anagem ent o f parking places located w ithin the system effect area providing the drivers th at have intelligent parking cards w ith an early reservation o f the parking places.
f) Inform ation M ed ia C ontrol -
It provides a current inform ation about the status o f the public transport, parking places and environm ent. It m anages 10 autom atic inform ation stands located at the key locations in th e city.
g) P ublic inform ation -
It uses the V ariable T ransport Signs (VM S) fo r transfer the inform ation about the easiest access routes to the various points o f the city and inform s about free places at the parking lots that are provided w ith the autom atic system s.
h) A utom atic A ccount C harging -
It enables autom atic paym ents w ith o u t stopping at the gates for the drivers o f appropriately equipped vehicles; it also enables purchase o f tickets to the public transport m eans using intelligent cards.
i) H ighest priorities -
T h e subsystem ensures priority for the rescue am bulances w hen they cross the intersection, served by the U rban T raffic C ontrol System ,
j) R outing -
T his subsystem enables drivers o f appropriately equipped vehicles to m ake them pass through the street netw ork in a way that optim izes travel tim e.
T he p roject o f the testing stage w as com pleted in 1997. A nalysis o f costs and benefits show ed a considerable reduction o f average travel tim e both the car traffic and public transport (17%
and 13% respectively) the increased travel efficiency resulted in drop in em ission o f flue gases and reduction o f fuel consum ption.
In addition, upon carrying out the analyses, tw o com ponent subsystem s have been shut dow n to the b enefit o f expanding th e U rban T raffic M anagem ent and R eduction o f E nvironm ental Im pact.
4.2. TRAFFIC MANAGEMENT SYSTEM WITH DISTRIBUTED INTELLIGENCE (UTOPIA SPOT)
T h e concept o f this system was a result o f com m on efforts o f the E uropean Union countries. It consisted in jo in in g the optim ization o f adaptation control (SP O T - Signal P rogression O ptim ization T echnology) w ith a supervision and diagnostic program (U TO PIA - Urban T raffic O ptim ization by Integrated A utom ation) [7].
T h is system enables the follow ing: synchronization o f intersections located w ithin the urban tran sp o rt netw ork, unconditional privilege fo r the public transport vehicles and special vehicles, and conditional and m ultilevel privileges o f public transport vehicles depending on their deviation from tim etable.
U T O P IA S P O T as a decentralized system consists o f the follow ing com p o n en t levels:
central m odule U T O P IA supervising and m onitoring the operation o f the entire transport netw ork; an intelligent S PO T co ntroller that optim izes control on insulated intersections and sm all netw orks as w ell as based on cooperation w ith the center, and local traffic controller that m ay b e integrated w ith SPO T. T he local traffic co ntroller realizes the task o f the intersection control based upon instructions received from the S PO T controller. The
D isp a tch e r’s control in the cities - main directions o f developm ent 291 com m unication betw een the center and SPO T controller may be interrupted from tim e to tim e, as this does not contribute to the interruption o f system operation (as it is the case with the centralized system s).
A n im portant feature o f the system is a possibility to assign priorities to the vehicles in three levels o f privilege. T he low est level results in an equal privilege for the public and individual transport vehicles. T he m iddle level assigns to the public transport vehicles a priority equal to 25 individual vehicles. It is used in the case o f deviation from the tim etable.
T h e last and highest priority may b e assigned only to the special vehicles (such as am bulances, police, and fire brigade). In m ost cities the equivalent for a special vehicle am ounts to 25o, how ever in certain areas (such as G oteborg) it m ay reach 2000 [7].
D ue to the solution applied as proposed by U TO PIA system it is possible to achieve a significant reduction o f travel tim e (public transport vehicles, individual vehicles, pedestrians), increased num ber o f public transport passengers resulting from growing attractiveness o f such transport, reduction o f vehicle operating costs, em ission o f flue gases and increased traffic safety.
4.3. URBAN TRANSPORT TRAFFIC CONTROL SYSTEM - KOMFRAM
T he K om fram system (used am ong others in G oteborg and H elsinki) serves prim arily the follow ing purposes: supervision o f traffic o f the urban transport vehicles, actions taken in the case o f traffic disruptions, and preparation o f a full passenger inform ation w ith its adequate distribution [3],
T his system is b u ilt o f two inter-linked system s: T raffic Supervision C enter (F ig .l.) and P assenger Inform ation C enter (Fig. 2.)
E ach v ehicle (constituting a part o f T raffic C ontrol C enter) has an onboard com puter C 90 installed, having in its m em ory inform ation concerning tim etables. T he onboard com puter operates the direction indicating boards, internal inform ation boards, announcing devices on the stops, ticket punchers, data collection system about the vehicle condition, and cou n ter o f passenger flow s. P resent location o f the vehicle is transm itted to the Traffic S upervision C enter (CN R) using a radio netw ork. T he com puters installed in CN R follow locations o f all vehicles connected into the subsystem . D isruptions in the traffic are signaled im m ediately and the dispatchers may use their best efforts to rem edy them.
292 K atarzyna TRZA SK A
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Traffic supervision
Center
Passenger Information
Center
Base tran sm it-tin g
device
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F ig .l. Traffic Supervision Center Subsystem
T he P assen g er Inform ation C enter subsystem cooperates w ith C N R in order to obtain inform ation concerning location o f all the vehicles. U sing this inform ation it is possible to forecast the tim e o f arrival and departure for all vehicles and stops. T hus obtained, these data are transm itted to the term inals located at the m ore im portant points o f the city, to the inform ation boards on the stops. T his inform ation is also available for cellular phones, Internet and pagers. T his subsystem also provides inform ation in the case o f m alfunction or longer interruption in the traffic.
D ispatcher’s control in the cities - m ain directions o f developm ent 293
Traffic Passenger
Cam eras in keySupervision <—
— >iInformation <f
--- locations of the cityCenter Center
Cellular phones
Network phones Pagers Internet
Inform ation term inals
Inform ation boards on node stations
Inform ation boards on stops
O nboard information boards
Fig.2. Subsystem o f Passenger Information Center
5. C O N D ITIO N S N EC ESSA R Y FO R T R A N SF E R O F EX PE R IE N C E FRO M T H E E U R O PEA N CO U N TR IES TO PO LA N D
W hen com paring the situation o f Poland on the background o f the W estern Europe C ountries, the m ost im portant problem s seem to be those related w ith econom ical transform ation and changes that affected the entire transportation sector.
Poland is a country w ith high share o f public transport in the urban transportation.
M aintaining this direction is ju stified by technical, econom ical and environm ental reasons [5].
T his requires, how ever, constraining m any disadvantageous tendencies resulting in a p erm anent grow th o f crow ding in Polish cities. As it is w idely know , it is not possible to follow the expanding m otorization w ith developm ent o f roads and parking lots. T his results in an expanding support for the idea that supplies should be m atched to dem and for the public transport services. T his idea is becom ing increasingly popular in the European U nion countries. O ne o f the basic factors for realization o f this policy is a priority treatm ent given to the p ublic transport (in relation to the individual one). T he developm ent o f transport telem atics gives new opportunities to m eet these challenges.
As show n by researches, the application o f telem atic solutions to the traffic engineering gives far m ore advantages that the geom etric solutions [7]. T hus it is purposeful to im plem ent such solutions in Poland (w here additionally poor technical condition o f transport infrastructure results in a grow ing crow ding o f city streets).
An im portant condition is im provem ent o f availability o f know ledge concerning transport telem atics betw een the decision-m akers. T his is a sine qua non condition to obtain from them , political support and funds for telem atics. T hus a need arises to review various international telem atics solution and developm ent o f cooperation betw een countries w ith sim ilar transport requirem ents. L im ited funds still rem ain a problem (an insufficient quantity
294 K atarzyna TR ZA SK A o f financing sources constrains the im provem ent o f infrastructure and increase o f telem atic system applications), thus it is necessary to look for alternative financing for transportation projects. A special attention should be paid to the cooperation o f private and public sectors and adequate distribution o f obligations betw een them [4],
D uring p lanning o f new telem atic solutions w e have to rem em ber that a basis fo r their successful realization are ap plicable institutions and such persons as the project authors politicians and decision-m akers w orking together.
W e alw ays have to rem em ber about adopting specific telem atic projects to the local conditions and needs (geographical, econom ical aspects, specific urban infrastructure a present status o f d evelopm ent o f electronics and autom ation), to achieve the best relationship betw een benefits gained and costs incurred.
6. IN STA N C ES OF T R A N S P O R T T E L EM A T IC S SYSTEM S IN PO L ISH CITIES
6.1. TRAFFIC MANAGEMENT AND CONTROL SYSTEM CITYMAN
T his p ro ject w as im plem ented w ithin an international E ureka program in Poznan in 1998. Its basic p urpose w as to enhance the standards o f the traffic lights controllers in the urban area covered by th e program (including the m ain transport artery). F o r this purpose, each o f the controllers was provided w ith a “black box” . It is a single-chip com puter com m unicating w ith the co ntroller located at the intersection and controlling specific traffic param eters. F o r this purpose, each “black b o x ” was provided w ith a universal protocol o f the
“m aster” type w hile the independent co ntroller w as provided w ith the “slave” type adapted protocol [4]. N ow it is p ossible to control taking into account the presen t traffic level, central supervision and optim ization o f netw ork operation. T he block diagram o f the “black box”
together w ith the concept o f com m unication w ith the existing controller is presented on Fig. 3 [9].
T h e im plem entation o f Citym an system enabled im proved coordination and increased capacity o f the m ain artery o f the city by ca 30% . In order to realize the project tasks the consortium consisting o f a leading D utch sup p lier and P olish consulting com pany PolT raffic applied for financial support w ithin the international E ureka program . T his p ro ject constitutes a good instance o f cooperation betw een the public and private sectors (Poznan C ity and the consortium ). In the situation th at the public sector is unable to carry out single-handed certain investm ent projects and incur the operating costs, such m odel o f cooperation is often profitable.
D isp atch er’s control in the cities - m ain directions o f developm ent 295
Fig.3. Block diagram of „Black box”
6.2. TRAMWAY TRAFFIC SUPERVISION SYSTEM SNRT 2000
T his system w as installed in the year o f 2000 in W arsaw and now it controls 350 appropriately equipm ent tram ways [10]. T he SN R T 2000 system consists o f the follow ing basic parts (Fig. 4.): D ispatcher C enter that coordinates and supervises operation o f the entire system , C om m unication C enter w ith its base station for transm ission and phone com m unication; D epot C enters connected and cooperating w ith the T raffic Supervision C enter and T raveling D evice located onboard at the d riv er’s stand, serving the purpose o f data transm ission and phone com m unication w ith the D ispatcher’s Center. T he T raveling D evice has a built-in GPS receiver enabling determ ination o f current geographic coordinates o f the supervised vehicle. T h ese coordinates are used to calculate the com pliance w ith the tim etable and w hen transm itted to the C enter they enable visualization o f present location o f each train on th e d isp a tc h er’s m onitor.
A fter installation o f this system , the im provem ent o f quality o f the transport services w as im m ediately visible in im provem ent o f travel conditions, such as tim ely arrivals and departures, su p p o rt o f generally understood safety in the city, p ossibility o f instantaneous reaction to the m alfunctions notified, b etter use o f rolling stock and its increased durability;
reduction o f the operating costs.
296 K atarzyna TR Z A SK A
A C O U S T I C B A S K S T A T I O N
D A TA T R A N S M I S S I O N
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O P E R A T IN G P L A N T S P l a n t C o m p u t e r
Fig.4. Basic components of SNRT system
7. CO N CLU SIO N S
C om parison o f P oland w ith the developed European countries is n o t favorable, w hen it com es to the im plem entation o f the urban traffic control system . H ow ever, the process o f degradation o f p ublic transport in P oland, lasting for over 10 years show s certain lim ited tendencies. T he global num ber o f passengers transported becom es m ore stable, the service quality and m anagem ent efficiency in the transport com panies are im proved. P olish transport com panies now start to see enorm ous opportunities offered by the solutions already im plem ented and renow ned in the W estern E uropean countries. E uropean experience shows that the investm ents related w ith im plem entation o f telem atic system s in the cities are several tim es m ore efficient that the traditional im provem ent o f geom etry.
In the conditions o f lim ited funds for the im provem ent o f transport system in Polish cities, im plem entation o f In telligent T ransport System s seem s to be difficult. H ow ever, we have to rem em b er abo u t th e possibility to acquire funds from international aid program s.
Poznan is a good instance o f such aid as it obtained support from international T ransport P roject E ureka in am ount o f 1 m illion Euro for realization o f the C itym an project.
14 July 2000 P olish L ow er H ouse o f the P arliam ent has passed a D ecision about establishing b ase for Inform ation C om m unity in P oland. T his act applied also to the transport system s. It w as a response o f Poland to the E uropean plan “eE urope” concerning a general action plan for m odernization o f E uropean econom y. O ne o f its objectives was expansion and im plem entation o f ITS system s.
C O M M U N IC A T IO N C E N T E R
T R A F F IC S U P E R V IS IO N C E N T E R
D isp atch er’s control in the cities - m ain directions o f developm ent 297
P resently several Polish cities undertook actions to im prove the quality o f the public tran sp o rt services. Several am ong them have already im plem ented transport telem atics solutions. T his is com forting, because it show s that the issue o f adapting such technologies to the P olish condition does n o t have to necessarily becom e an insurm ountable technical and financial obstacle.
B IB LIO G R A PH Y
[1] LEŚKO M., GUZIK J., Sterowanie ruchem drogowym. Wydawnictwo Politechniki Śląskiej, Gliwice 2000.
[2] PAJĄK A., Zielona fala. Enter, nr 9, September 2001.
[3] PAP1ERKOWSKI K., Sterowanie ruchem w komunikacji miejskiej w Skandynawii na przykładzie systemu Komfram. Zeszyty Naukowo - Techniczne Oddziału Stowarzyszenia Inżynierów i Techników Komunikacji w Krakowie, book No 64, Kraków 1998.
[4] Project CAPE (TR 4101/IN 4101), Final list o f appropriate practices (transport telematics) - review of telematics application in Middle European countries, November 1999.
[5] ROZKW ITALSKA C„ RUDNICKI A., SUCHORZEWSKI W., Rozwój miejskiej komunikacji zbiorowej w Polsce w latach 1995 - 2000 i kierunki rozwoju po 2000 roku. Publication of IGKM, 2001.
[6] RUDNICKI A., Jakość komunikacji miejskiej. Publisher SliTK, Kraków 1999.
[7] Internet page: www.peekUaffic.nl - materiały dotyczące systemu UTOPIA SPOT.
[8] Internet page: www.rec.org/REC/Programs/Telematics/CAPE/goodpractice/tmsprt/doc/TURIN-pl.doc. - Internet page concerning project 5T.
[9] Internet page: www.rec.org/REC/Programs/Telematics/CAPE/goodpractice/tmsprt/pdf/poznanen.pdf - Internet page concerning project Cityman.
[10] Telekomunikacja & Telem atyka. No 4 September 2000, No 7 August-September 2001, No 4 October 2001.
Review er: Prof. R om uald Szopa
