Behavior of intelligent stops for the vision impaired

Behavior of intelligent stops for the vision impaired

This text was written for the purposes of describing the behavior of information stop panels (intelligent stops) when they receive a command sent by the command transmitter for the vision impaired to provide acoustic announcements.

Behavior of intelligent stops according to the regulation 398/2009

When intelligent stops or electronic information panels receive a command from a command transmitter for the vision impaired, they must behave according to the regulation no. 398/2009 Sb. Supplement no. 1, paragraph 1.2.8 (the way of using trill) and 1.2.9 (ways of remote control)  issued by the MMR (Ministry of Regional Development). This regulation defines the basic stop panel behavior. The following text are go beyond the scope of the regulation and define possible behavior of modern transportation systems.

According to the regulation it is necessary to observe the following demands:

  1. The “infosystem” trill must be 1/3 louder than the following voice phrase (to help the vision impaired to orientate themselves). The type of the “infosystem” trill is not defined.
  2. The command table that states that intelligent stops must use commands no. 1 and no. 6. The table contains the following:
Command no. 1 For activating a common orientation beacon in the surroundings (e.g. a trill, a voice) either once (pressed shortly) or repeatedly (pressed long).
Command no. 2 *) For supplementary (particularizing) announcements e.g. office hours etc.. In the case of stops and stations we recommend e.g. announcements of traffic closures or unusual traffic situations.
Command no. 3 A command that summons voice information about the number of the line and the direction of the public transportation vehicle (announcements outside the vehicle).
Command no. 4 A confirmation for the driver of the fact that a vision impaired person has entered the vehicle, a notification for the driver of the fact that a vision impaired person is going to get on/off the vehicle (announcement “attention! A handicapped person”). A space orientation trill can be added and a self-access door opening can be activated.
Command no. 5 Used to activate junction sound signalization for pedestrians (knocking or “croaking” of junction traffic lights).
Command no. 6 Reads the content of an electronic display panel i.e. the connection, the target stop, the departure time or the time remaining until the vehicle arrives etc.
Command no. 7 Combined transmitting of a number of the above commands one after the other (only on white sticks – not defined independently).

*) Command no. 2 can only be used to read a notification text on the panel or other particularizing information. It is not defined by the regulation but it is advantageous to use it in the standard way- see the following.

Possibilities of stop panel announcements for the vision impaired

Basic system organization demands

Acoustic information announcements for the vision impaired are usually solved as a decentralized system. i.e. every information point (stop panel) contains an acoustic database of all used sounds at least for the given stop (this is usually not distinguished). Information about current departures is sent to every panel from the dispatching or the control department. All information consists of a textual part for displaying and an acoustic part for playing sounds.

This brings the following demands:

  1. Every panel must have a corresponding acoustic database, i.e. it must contain all the sounds used for announcements for the vision impaired, i.e. stop names, numbers, support announcements, and gongs. Today xxx.mp3 files are usually used.
  2. The names of these files must be the same as file names in the dispatching center that sends information about departures to the panels. As has been already stated above, this information usually has two parts – optical (displayed on the panel) and acoustic (announced at a request).
  3. Using direct sound recordings is an advantage in comparison with announcements based on converting texts to announcements (text-to-speech). This solution ensures high quality of played sounds.
  4. It is advantageous if the dispatching system contains a unified list of sounds including remote announcement loading in vehicles and not only on the panels – a unified format.
  5. A panel should contain an acoustic database for announcements when the panel is in off-line mode, i.e. it does not receive any data from the dispatching (so far this solution has not been used).

Commands used for command controllers for the vision impaired

The behavior of digital acoustic annunciators of  information stop panels (ELP) for the vision impaired citizens observes the following demands and is described below. It observes the rule stating that small texts signify predefined announcements firmly defined in the program of the digital annunciator of the stop panel and large texts in quotation marks are added variables (the numbering and labeling of these files depends on the supplier or the user):

Texts on individual lines are played using predefined audio messages. It is possible to skip to the next line – accelerated reading – by pressing the button no.6 of the remote controller for the vision impaired repeatedly.

Meanings of individual control buttons:
  1. Command no. „1″ reads the name of the stop only to orientate oneself towards the panel.
  2. Command no. „2″ plays additional and traffic closure announcements (depending on the requestor) – made possible by panels supplied by the Herman company.
  3. Command no. „6″ plays information about departures from the panel.

Reaction to command no. 1 

Command no. „1″ selects the following simple sequence:

trill + pause_1s + stop + „THE NAME OF THE STOP“

Reaction to command no. 2

Command no. „2″ can select the following sequence that provides the vision impaired with additional information about the stop and the time e.g. “a reconstruction of the stop XY is planned to start on 4.7.2014, it will be necessary to use an alternative connection, etc. . . . . “:

trill + pause_1s + „ THE NAME OF THE STOP “ + the announced text

Reaction to command no. 6

Command no. „6″ selects reading of all information about departures and about the text on the bottom line of the panel. The text can be divided into a sequence of steps by pressing the button no.6 again. When using the sequence of steps, the read text is terminated when the loaded text is read (xxx.mp3).

Texts will be read in the following way if:

  1. the connection is standing at the stop,
  2. the connection is in irregular mode,
  3. the line will come in 0 to 60 s (up to one minute),
  4. the line will come in one to xx minutes (max. 60 minutes),
  5. the line will come at a defined time,
  6. there is a text on the bottom line of the panel
  7. the sign is in autonomous mode,
  8. there is no data to display.

Ways of announcing departures from a stop

As stated above, reading of departures is commenced in response to command no.6 sent from a remote controller for the vision impaired. This is the reason why we distinguish the following situations:

Basic reading of a text from a stop

Basic reading of a text from a stop includes a trill, the name of the stop followed by gradual reading of the content of individual lines. The reading can be divided into a number of parts with the initial sequence as follows (the name of the stop is announced):

trill + pause_1s + „THE NAME OF THE STOP“ + ….……

Then basic reading of each line follows (except for information lines from the dispatching) and the number of the line, the target stop and time information (see below) are announced. If a wheelchair-accessible vehicle arrives to the stop, information about this vehicle can be added to the announcement (it has to be supported by the system). The announcement comes in the following form:

+ line number + „THE NUMBER OF THE LINE“ + direction + „THE TARGET STP“ + {low-floor vehicle} + ….

Announcing information about departure times

Announcements of departure times depend on the current state of the traffic and on the ability of the panel to obtain information that a vehicle is standing at the stop either by communicating directly with the vehicle (vehicle – panel communication) or by using accelerated communication with the dispatching..

The connection is standing at the stop

For this function to be possible, panels must either communicate directly with vehicles (a special radio communication vehicle-stop signal is used) or they must use a communication network allowing them to communicate with the dispatching (vehicle-dispatching-stop) with minimum delay.

This panel behavior is based on the following : if the connection is standing at the stop and the fact is indicated e.g. by displaying a symbol of a vehicle where the departure time is normally displayed, the following sentence is read out loud (the list of the read sounds is to be found in the preceding subchapter):

…. + the vehicle is checking in at the stop +


After reading this text the panel continues with the following line if the just read line is not the last one. If the vehicle has already closed the door and is leaving the stop (indicate by a blinking symbol of a vehicle) this line is not read at all.

The connection is in irregular mode

This situation is defined for urban agglomerations for cases when there is a seamless line of vehicle and it is not possible to predict when the connection arrives to the stop (indicated by a text saying “irregular mode”). Displaying regular departures of the given line from the stop is terminated because of that. The read text is as follows:

+ running in irregular mode + < the following line is read > ….

After reading this text, the panel continues with the following line if the just read line is not the last one.

Solutions for other unusual situations will be similar; the following texts will be displayed on the line usually displaying the time until departure and the target stop:

  • operative running: announcement „the traffic is controlled operatively“
  • the stop has been moved: announcement „the stop has been moved temporarily“
  • a traffic accident: „the line is blocked by a traffic accident“
  • a barrier on the route: „the line is blocked by a barrier on the route“
  • a redirection: „the route of the line has been temporarily redirected“
  • cancelled: „the connection has been cancelled“

Information about departure times

The system of displaying departure times from the stop is designed in such a way that it is possible to display the number of minutes until the departure or directly the time of departure. This value differs depending on the operator of the panel and on the type of transportation. The following types of announcements are distinguished:

The connection will arrive in one minute 

If the connection (vehicle) is arriving to the stop and it should be there in 0 to 60 s the announcement “in one minute” is read. The whole text looks as follows:

…. + will arrive in + one minute + < the following line is read > ….

After reading this text, the panel continues with the following line if the just read line is not the last one.

The connection will depart in one to xxx minutes

If the connection leaves in 1 to 60 minutes this information is displayed in the form of a number representing the number of minutes until its departure – displayed on the panel as – “xx minutes until the departure of the connection”. The name starts to be counted from two minutes according to the display (the time from 60 to 120 seconds until the departure). The read text looks as follows:

…. + departs in + „NUMBER“ + minute(s) + < the following line is read > ….

After reading this text, the panel continues with the following line if the just read line is not the last one.

The connection will depart at a defined time

If the connection arrives in a long time it is difficult to count the time of departure in minutes and the format of an accurately defined departure is used. From a chosen time on the server (or a configuration time on the panel) the line is displayed in the format e.g.: 14:52. Announcements for the vision impaired must observe this display format.

+ departure + „NUMBER“ + hour(s) + „NUMBER“ + minute(s) + < the following line is read > ….

After reading this text, the panel continues with the following line if the just read line is not the last one.

Reading messages from the dispatcher

A dispatcher can send a text to the stop sign. This text is usually displayed to passengers in the form of a moving text on the bottom line of the panel. If displayed in such a way the text is read last. This means that if e.g. a 5-line panel displaying four and four lines is used this text is read as the ninth one. To make this possible, panels must contain corresponding sounds or it must be possible to put the announcement together using various sounds uploaded in the panel. The announcement itself is preceded by “information from the dispatcher”.

+ information from the dispatcher + „ANNOUNCEMENT“ +

After this text is read the panel turns the amplifiers off and remains silent.

Apart from the simple „ ANNOUNCEMENT “it is possible to piece the text together as follows:

+ information from the dispatcher + running of the lines + „NUMBER“ + „NUMBER“ + is blocked by a traffic accident < end o the announcement >

…i.e. one or two optional mp3 and reading of one number or a list of up to eight line numbers

Autonomous mode of stop signs

As stated above, for this mode to be functional, the panel must contain not only a database of displayed departures but also a database of acoustic departure announcements. The term autonomous mode of stop signs signifies a system where the connection is announced on the basis of a locally stored schedule (e.g. when communication with the dispatching has been severed) or the information is sent directly from the dispatching (the connection does not send data about its position but it is on the way). The panel displays a corresponding symbol indicating this fact, e.g. ±.

In such a case the announcement “there is no information about the position of the connection, a planned departure” is added to the departure information behind the text on the beginning of the line:

+ {wheelchair-accessible} + line number + „THE NUMBER OF THE LINE“ + direction + „ THE TARGET STOP“ + there is no information about the position of the connection

+ planned departure in ….(1 to xx minutes)


+ planned departure ….(time in the format  yy hours, zz minutes)

Panel does not have data for autonomous mode

If the panel is running, the communication is down and the panel does not contain an up to date schedule and a database of announcements i.e. it is not able to provide the needed information to the vision impaired, the panel only announces:

 trill + pause_1s + „THE NAME OF THE STOP“ + the panel is out of order