Transportation terminal information systems

The Principle of transportation terminal information systems

Transportation terminal information systems are designed for the purposes of easy passenger orientation in a transportation terminal. Their main purpose is displaying information regarding public transportation vehicle departures. There are usually two levels of information:

• information regarding the earliest departures (arrivals) from/to a platform,
• overview information regarding what is happening in the whole terminal (departure and arrival panels).

Panels for terminals are produced in various sizes and renderings. The solution depends on the frequency of departures and arrivals from/to a platform and on the overall arrangement of the terminal (access roads, check-in halls, waiting rooms/areas). It is necessary to solve:

• departure panels of individual platforms
• outer overview panels of the terminal
• inner overview panels of the terminal
• a clock system

Departure panels of individual platforms

In this case, LED panels are the most suitable because of energy saving, their lifespan and also their readability when exposed to sunlight (if the distance is more than 3-5 m LCD panels are less readable). A departure panel usually displays 1-3 departures and if needed also one dispatching line. Panels can be both graphic and text.

The size of the panel is chosen according to the arrangement of the terminal and departure stand requirements. If departures are to be readable from a distance an 8 mm LED diode rastr is suitable (readable from distances of up to 35 m). However, LED panel space requirements must be kept in mind – if 32 signs are to be displayed the length of the panel must be at least 1400 mm. The ELP 40x panels can be used as an example of such panels.

On the other hand, it is possible to produce a panel with 4,2 or 5 mm LED diode spacing for a digital sign. Then the size of the embedded panels is up to 81 cm with 32 displayed signs (5 mm LED diode spacing). If even this is too much the smallest meaningful displaying is 24 signs with the panel width of 51 cm (4,2 LED diode spacing). It is also possible to use two-line displaying of one departure (e.g. the second line contains following stops). Such a panel is readable from 15-20 m. Digital signs modified to suit the needs of the terminal can be used as an example of such panels. The picture below shows a 30 x 160 LED with 4,2 diode spacing including a system for the vision impaired (ELP of the 15x series).

Outer overview panels

Outer overview panels are placed where passengers gather or where they have to pass through which is why such panels are required to display information using big enough letters (usually 50 mm or bigger) and to be readable from distance. Here again LED panels are the most suitable mainly if the panel is to be placed in direct sunlight. This corresponds with 8 mm LED diode spacing and  panel size of 2 m.

Overview panels usually display more information, i.e. the number of the line and of the connection according to the CIS (central information system) and the number of the line according to the IDS[1] (usually a 3-figure number), the target stop including stops on the line, the platform and if needed also delays (if on-line vehicle surveillance is at one’s disposal). The ELP 45x panels  (a multicolor rendering for distinguishing kinds of connections) and the ELP 41x panels (a simplified single-color solution)  can be used as the most typical examples.

Inner overview panels

Inner overview panels are suitable for check-in halls and waiting rooms/areas, i.e. where there is no direct sunlight and panels are viewed from shorter distances. In this case both LED panels (lower power consumption, longer lifespan) and LCD panels (usually a little cheaper) can be used. The advantage of LCD panels is that they allow full color  displaying of departures and other graphic symbols and pictures while displaying more departures at the same time. We do not recommend using standard televisions or computer monitors because of their shorter lifespan and lower luminous intensity.  Here you can find a demonstration of a primarily inner LCD panel that uses an LCD monitor and has a lengthened lifespan.  Here (the outer LCD panel site)  you can find a demonstration of LCD panels designed for environments with a quite substantial amount of sunlight.

Clock systems

Clock systems are designed to display exact time and date. There are various versions – they can be displayed on a dispatching line of a panel (see the ELP 30x panels ) or separately on a panel (see the ELP 821 and 842 panels) or they can be designed as central independent clocks (see the four-sided  ELP Q524E panels). Clock systems can be controlled using exact times obtained with the help of a DCF clock transmitter, data obtained from GPS or other devices (e.g. the internet).

Organization of a terminal information system

The terminal information system technology is to be seen in the following picture. To lower panel prices a terminal usually contains a control computer (a terminal control server) that controls all panels based on lines, therefore panels (especially on departure platforms) do not need basic panel control units, they only need LED board control units which lowers their prices. Terminal control servers also contain off-line departure (arrival) schedules that are displayed on individual panels. If there is a superordinate server that contains vehicle position data panels can also display up to date departure data including delays. Terminal attendants or the dispatcher of the superordinate server must be able to send needed information to individual panels e.g. regarding a lockout of the line A sent to overview panels and to the corresponding departure panel.

Data transfers to the panels can be performed in a number of ways:

• RS 485 busbar – it ensures a reliable connection between the terminal server and the departure panel. It is suitable mainly for controlling text panels (departure or overview) where there are no large data currents (e.g. changing two lines every minute). Usually it is possible to change firmware or configure the panel remotely. To ensure a reliable solution the busbar must be galvanically separated from the wiring to prevent “dragging in” of power surges into the panel or the server since it could damage them. If there are more directions in the panel an RS 485 “hub” must be used. However, it is still the cheapest solution of data transfers.
• ethernet busbar – creates a modern and fast connection between the server and the panel. Since the range of an ethernet busbar is 60-100 m it is necessary to take this distance into account and place data signal repeaters (e.g. switches) accordingly. This is the reason why ethernet busbars are suitable mainly for smaller terminals. This busbar must be used when LCD panels are used. These panels usually contain PC or ARM computers whose updates usually require transmissions of large data files.
• optical fibers – be it single-mode or multi-mode fibers, they still permit for data transfers over the distance of more than 100 m and at the same time ensure perfect galvanic separation. The wiring is usually designed as 1:1, i.e. each panel is connected using one optical fiber. Such a fiber must be equipped with a “media converter” unit on each end. This unit sends light rays to the ethernet busbar and vice versa. On the side of the panel the media converter is directly integrated into the panel while on the side of the server there has to be a set of media converters (e.g. our SMK 10/196) that is placed on the server stand and in the ethernet switch. This solution is a little more expensive but also more reliable.
• wireless connections – are usually realized using the WiFi technology. Such a connection is suitable mainly in places where there is an information system realized in an already “finished” terminal (it is added to the terminal).

Examples of transportation terminals realized by our company

Transportation terminal in Ostrava – Svinovské mosty

At the end of 2012 we supplied an information system for the renovated transportation terminal Svinovské mosty. The set contained double stop LCD panels equipped with clock LED panels, and a four-sided central terminal clock. A clock system obtaining exact time information via GPS was also a part of the information system. The data distribution of the terminal is solved using optical fibers and ethernet.

Transportation terminal in Cheb

The following picture shows a part of the newly built transportation terminal in Cheb. In 2012 our company supplied departure LED panels (red and white) and large eight-line overview text LED panels for this terminal. Data distribution is solved using optical fibers. The supplied panels are of the ELP 40x and ELP 41x types.

Transportation terminal in Nové Město na Moravě

The following picture shows a demonstration of the information system for the small transportation terminal in Nové Město na Moravě that we realized in November 2012. Data distribution is solved using an Ethernet busbar. The panels are of the  ELP 32x type.