Intelligent Roadway Information System
Dynamic Message Signs (DMS)
View ➔ Message Signs ➔ DMS menu item
A dynamic message sign (DMS) is a sign which is capable of changing the message displayed to motorists. They can be classified as character-matrix, line-matrix or full-matrix depending on the spacing between pixels. Some are monochrome and others support full color display. All of these configurations are supported.
The following features are supported:
- Querying currently displayed message
- Displaying new messages
- Querying configuration information
- Querying diagnostic information
- Querying or sending fonts
- Sending graphics
- Travel time estimation
- Variable speed advisories
- Slow traffic warnings
Each DMS can have a number of styles, depending on its current state. Styles are ordered by precedence, determining which color a map marker is drawn.
|Available||Sign is blank and ready to use|
|Deployed||Displaying an operator-defined message|
|Schedule||Displaying a scheduled message|
|External||Displaying a message from an external system (not IRIS)|
|Maint.||Sign requires maintenance, but might still be functional|
|Failed||Communication failure to sign|
|Purpose||Dedicated-purpose sign (travel time, wayfinding, etc.)|
There are a number of fields available for configuring a DMS.
|External beacon||beacon controlled when sign messages are deployed|
|Static graphic||image of static sign in which DMS is inset|
|Device purpose||general or dedicated purpose for sign operation|
|Hidden||hide sign when available or deployed styles are selected|
Sign groups and associated sign text libraries can be managed in the Messages tab.
All sign groups are displayed in the table, even if the DMS is not a member of that group. To add the DMS to a group, select the Member check box.
When a sign group is selected, its message library is displayed in the sign text table. Each row contains a message for one line of the sign. The rank determines sort order in message lists.
The message preview displays a graphical rendering of the selected sign text.
Select an override font to use a font other than the default font from the sign configuration.
MULTI is the MarkUp Language for Transportation Information used to
compose DMS messages. It is defined by the NTCIP 1203 standard. Messages in
MULTI are ASCII strings, with formatting or other instructions denoted by
tags inside square brackets. For example, the
[nl] tag indicates a new line.
Most of the useful MULTI tags are supported.
||Message background color||Yes|
||Page background color||Yes|
A quick message is a fully composed DMS message which can be associated with a sign group. They are created using the WYSIWYG editor.
When a DMS is selected, a drop-down list is populated with quick messages from sign groups of which that DMS is a member. Quick messages are also used for DMS actions as part of an action plan. For these messages, it is best to leave the sign group blank.
Prefix Page is a flag which indicates that the quick message can be combined with an operator message. When a DMS action uses a prefix page quick message, operator messages will be modified by prepending the quick message before each page. Care must be taken to ensure the combined message can be displayed on the sign. This feature could be used, for example, to put a graphic logo on all messages displayed on a sign.
View ➔ Message Signs ➔ Words menu item
DMS messages can be checked against allowed and banned word lists when an operator presses the Send button.
Allowed word checking is controlled by the
||Disable checking allowed word list|
||Suggest replacement of words not in allowed list|
||Reject messages containing words not in allowed list|
This list is also used for abbreviation of incident DMS messages.
dict_banned_scheme system attribute controls banned word
||Disable checking banned word list|
||Suggest replacement of words in banned list|
||Reject messages containing words in banned list|
When appropriate, a form appears to suggest changes or inform the operator of a rejected message.