Control and supervision of transportation systems

Ing. Ivo Herman, CSc.

New demands on control, supervision and checking require new approaches and system solutions. It is therefore necessary to change not only vehicle composition but also control, supervision, and checking systems on the level of cities and regions. These changes are made possible  by new vehicle technologies, communication technologies and data processing technologies. All these features make way for changes in the conception and philosophy of transportation system functioning. This will enable us to develop said systems, search for new possibilities and functioning principles and to satisfy the above-standard needs of the modern time. This article deals with three conceptions and summarizes the changes happening in the field of dispatching control and checking.

What systems can be controlled?

There are many transportation control systems that can be controlled individually with regard to their function and arrangement. We are talking about providing information about vehicle position, vehicle state, and passenger checking in complex systems of dispatching control, remote vehicle, stop and passenger supervision in the form of a number of solutions.

There are many versions of dispatching control SW (the Herman company presents SW “SPRINTER” in many of its solutions):

• for municipal PT transportation companies,
• for regional PT transportation companies,
• for regional dispatching of IDS (integrated transportation system).

Other control SW is designed to control individual components in “the terrain” and can be connected to superordinate dispatching applications:

• for stop panel control in vast regions including combinations (usually of regions or cities),
• for transportation terminal control (local control of displayed information in the scope of e.g. transportation terminals),
• for city platform control – combination of controlling public transport, parking, intersections and other features in the scope of a city,
• for remote centralized control of vehicle information panels where everything is controlled from the center – e.g. an airport

Backoffice systems are also very important SW tools (in the case of the Herman company it is BOS – BackOffice System) as they are designed to process checking information from vehicles and also to supervise vehicles from the technical point of view e.g. data uploads into vehicles and monitoring their state (can also be e.g. a part of traffic control dispatching). They also include multiple access for many transporters who manage their own vehicles in one system and the system administrator manages general features of all of them.

Other possible server applications can provide:

• control of adds on vehicle LCDs – so called „advertisement“ dispatching (e.g. INFORMATION ADVERTISEMENT SYSTEM),
• control of adds on stop LCDs – stop systems combined with adds or information about the city (SW DARWIN)
• control and supervision of uploading/reading data to/from vehicles, this data includes operation data or data about passenger behavior e.g. WiFi in vehicles, V2X units (units for monitoring communication among vehicles) and others.

Independent control systems

Independent control systems are systems that are used to control this system and they are the historical beginning of transportation monitoring within transport companies. The core of this system is the SW of a CED server (CEntral Dispatching) e.g. municipal PT control application. It has communication connections in various directions:

1. The basis is comprised of gathering of vehicle position information and other operation information. An independent radio network suitable also for voice communication (urban companies) plays an irreplaceable role in such a system. Today, it integrates voice and data communication with vehicles.
2. Auxiliary GSM network with LTE transfers is mainly designed for data “demanding” communication, on-line updates, or also “data” phonic updates, or communication suitable for vast systems of regional public transportation.
3. Independent internet in the form of Wi-Fi for passengers used to make public transport more attractive.
4. Data updates/downloads in depots or garages (operation, camera recordings, progress of the drive, etc. for offline evaluation). Updates can be triggered after arrival to the depot or by scheduled waking of idle vehicles or by waking on demand using low input power radio communication (e.g. FHSS communication). When e.g. camera systems are used, these networks require using fast communication standards – e.g. up to 430 Mbit/s which significantly changes vehicle structure.
5. Public transportation vehicle preference and communication using V2X (vehicle to everything) – a new communication standard based on the European norm C-ITS G5 including processing of supervision of controlling units placed in vehicles and in intersection controllers .
6. Communication with a superordinate dispatching marked CED REAL or with another cooperating dispatching to get traffic illustration of places where traffic controlled by different dispatching permeates. Currently this way is the pushed one and there is a number of solutions.
7. Output API interface for handing data over to other systems or for various mobile application and information portals and for e.g. virtual ELPs (dynamic markers) in vehicles.
8. Other data source connections such as schedules, map data, vehicle dispatching, etc.

The pic. no. 2 shows a possible arrangement of this system. The basic structure of the dispatching system is client-server.

The basic functions of traffic control dispatching systems are:

• Voice communication with vehicles and their drivers, acoustic announcements for panels in GSM networks or in private radio networks together with various types of station addressing – from selective to general.
• Periodic calling/receiving of data from public transportation vehicles to determine their position, to display it on a map and to evaluate it automatically in relation to a schedule including predictions of future behavior even of the following connections (spread of exceptions in the future).
• Manual or automatic sending of state and text messages between the dispatcher and the vehicle mainly in the case of successive systems.
• Additional information – possibility of indicating the state of the feeding system and heating in vehicles mainly in trams and trolleybuses, technological vehicle surveillance, panel technical state supervision, etc.
• There are also other improvements such as going through history, possibility of “having a look in” the future, driver break control, various types of warnings and non-standard state notifications, event lookup, various filtration types, etc…

Touchscreen control panels are supplied to simplify communication and provide quick control. They provide a quick overview of the state of the network and quick clear choice of a communication channel – radio, phone, etc…

In the field of control and supervision systems, there are also independent specialized “dispatchings” (thanks to the modular conception of dispatching SW) providing independent operation of ELP (Electronic Panel) control:

• Automatic sending of messages about vehicle departures to information panels.
• Automatic evaluation of vehicle position in regard to the schedule and the stop where the panel is placed.
• Principle of „flagging“ – i.e. labeling of lines or connections and regions, definition of temporary exceptions for these lines – e.g. delay + 5 minutes because of connection, a vehicle in a tailback, delay in the section etc.
• Possibility of sending automatically generated messages as per the calendar to stop panels for passengers.
• Possibility of animating the history of displaying data on panels – so called „replay“ mode with various animation speed.
• System of notification about non-standard states etc.

Regional arrangement of synchronized systems

There is a new trend of interconnecting dispatching control systems and shared traffic information which increases the quality of operational control in during traffic issues. Two types of communication are used:

• Data exchange using communication protocols that mainly transfer information about “cross-border connections” between control regions of these systems. This enables dispatchers to see what is happening  on the borders of the system and how arriving connections will affect  the behavior of “their” system.
• The other possibility is full synchronization of systems mainly in a region and the transportation company of the regional city  (described below)

The pic. no. 5 shows the system control structure where individual dispatching servers – of the regional coordinator and of the transportation company – are mutually synchronized on the level of databases and chosen information based on communication protocols. This arrangement solves situations when control of municipal and control of regional transportation permeate each other including connection control and transfers from one transportation to the other. The control functions are interchangeable in many ways mainly during schedule creation and information panel control when one stop panel can receive information from one or the other dispatching.

Generally in such cases, the way of synchronizing depends on requirements – from full server database synchronization to mere transferring of information with the help of communication protocols.

New arrangement of a control and checking system

Technical development makes it possible for vehicle installation and consequently the arrangement of the whole traffic control to be changed. So far there have been two types of relatively independent systems in public transportation vehicles – information and checking. Each has had its own control unit and data processing. This arrangement has often caused creation of parallel systems in vehicles (including data communication) which has made vehicle equipment and maintenance more expensive.

The modern technology and its computing performance are able to ensure that there only is one vehicle control unit (VCU) in a vehicle that provides communication both with a traffic control dispatching server and a passenger “checking” server or other servers needed in the given system (data storage, accounting centers, camera system, Wi-Fi, ….)

The pic. no. 7 shows a possible arrangement of this complex regional system (city and region) when there only is one computer in a vehicle which solves:

• passenger checking:
  • communicates with a back office system and solves mainly prepaid tickets (line n. 2),
  • communicates with TAC (transportation accounting center) and solves current tickets   (line n. 3),
• traffic control and sends all needed data to the central dispatching – CED (line n. 1),
• data and add uploads, vehicle state monitoring – in this case the back office system solves this as well (line n. 2),
• when selling multiple zone tickets the VCU sends a request to find connections and individual zone composition during the ticket sale or communication with the customer (line n. 4),
• direct on-line or off-line payments by a bank card (line n. 5). In this case tokenization can be used and the payment  method and the price are processed in TAC (line n. 3).

The picture also includes data streams that bring data. It is clear that communication channels are independent of the GSM operator and the “independently” operating system of the TC (transportation company) of the regional city. However, all sold tickets (mainly one-time tickets) are spread to all vehicles through channels from TAC and its optimization will be underway.

For this system to function a new type of BackOffice System is used that ensures data and prepaid ticket management and simultaneously transfers data for VCU and processes data not only from checking. Its basic operations are (the Herman company uses BOS – BackOffice Ssystem):

• user and user right management,
• individual transporter management,
• vehicle and vehicle equipment management,
• checking management (tariffs, ticket creation, price list, deductions, transactions and their export),
• schedule management (editing, import export),
• and others ….

Other remote supervision types

In public transportation, other independent systems are often created that cannot be integrated into systems already in operation or that are accessed by multiple companies.

A typical system is e.g. control of adds or other information (region, city, … ) in vehicles as it can be independent of the public transportation provider. However, other vehicle data is needed to optimize adds, e.g. how many people were there in the vehicle, where and how many times adds were shown, in what time intervals, etc.. Adds can be shown on LCD displays in vehicles, on stops and on the vehicle or stop Wi-Fi.

The pic. no. 9 shows a possible arrangement where a remote server keeps vehicle data up to date via GSM/UMTS/LTE networks and stop data via public internet. Data updates happen immediately after a “new version” is generated by a Media Web Server. Each shown add notifies the server about being shown. The server itself downloads data about vehicle dispatching and schedules and based on that creates predictions about shown spots.

How to conclude?

The article lists a number of solutions of dispatching systems and their communication ranging from the historical solution (of course up to date so far) of only independent dispatching control, to new solutions of synchronized dispatchings and universal systems with multiple servers i.e. where the development in this field is heading at the moment. It turns out that the whole system is more and more compact and it makes solving many connections in traffic possible and thus increases its quality.

There are many competitive procedures for new vehicle informatics and mainly on-board computer arrangement under way at the moment. The arrangement choice will affect the development of vehicle services for at least the next 10 years. Therefore it is very important to choose well a vehicle solution from the point of view of computer networks mainly if we want to use all the possibilities of today’s technology.