GB2290644A - Graphical display for alarm system - Google Patents

Abstract

A building includes a fire alarm system having a plurality of sensor terminal devices. A graphical display system Fig. 2 maintains a map of the building. A building structure record memory 20, 22, 23 stores a plurality of building structure records each representing a structural feature of the building, a device record memory 24 stores a plurality of device records each representing the location of a terminal device of the alarm system, an area record memory 21, stores a plurality of records each representing an area of the building. Image control means control a display device 27 and process the records of the building structure record and device record memories to display a map of at least part of the building and the locations of the devices therein. If a sensor terminal device detects a danger condition, a message is generated. The image control means thereupon process the records of the area record memory so as to display on the display device, as fill areas, the areas within which the device is located. The messages are stored in time and priority sequence in two memories 40, 41. <IMAGE>

Description

COMPUTER SYSTEN The present invention relates to computer systems and more specifically to graphical display systems, particularly (though not exclusively) to such systems forming part of fire alarm systems.

Buildings of substantial size are now commonly fitted with fire alarm systems, using the term in a broad sense to include alarm and control systems generally. Such a system consists of a number of terminal devices, i.e. sensors (e.g. for flame, smoke, manual alarms, etc.) and actuator devices or alarm units (e.g. sounders, light flashers, etc.). These are all coupled to a control system, which includes a graphical display system for displaying a map of the building together with the locations and states of the terminal devices.

The general object of the present invention is to provide an improved graphical display system for generating, controlling, and/or displaying a fire alarm system map.

According to one aspect, the invention provides a system in which a map has a number of fill areas and, when a sensor device detects an alarm condition, the map is displayed with all the fill areas within which that device is located are displayed. The fill areas can be freely defined, so that a single device can cause several fill areas to be displayed and a single fill area can be displayed in response to any of several devices.

According to another aspect, the invention provides a system in which, when a sensor detects an alarm condition, a message is sent causing the display of the map with the corresponding sensor indicated, and including message storage means comprising a sequential list memory, a priority list memory, and means for storing message in the sequential list memory in temporal order and in the priority list memory in order of relative priorities of the devices associated with the messages.

A fire alarm system including a graphical display system embodying the invention will now be described, by way of example, with reference to the drawings, in which: Fig. 1 is a general block diagram of a fire alarm system; Fig. 2 is a block diagram of the central station of the system; and Fig. 3 is a more detailed block diagram of the control and logic unit of the central station.

Referring to Fig. 1, the fire alarm system, a master panel 11 and a series of slave panels 12-1, 12-2 are shown. The master panel and each of the slave panels has coupled to it a group of four loops 13, each of which can include up to 99 terminal devices 14 (flame sensors, smoke sensors, alarm sounders, etc.), as indicated in simplified form for loop 13A. The panels are arranged to provide suitable coupling between the sensor devices and the actuator devices, so that if a sensor detects a dangerous condition, the appropriate alarm devices are energized.

The system also includes a central station 10 which provides graphical display and control functions.

This is intended primarily for monitoring purposes, i.e. to inform an operator of the condition of the building (and more specifically which devices are active, i.e. which sensor devices are detecting dangerous conditions and which alarm devices are actuated. However, it can also be used for control purposes, activating alarm devices either automatically in response to the operation of sensor devices or in response to operator control.

The master panel 11 is coupled to the central station 10, and the slave panels 12-1, 12-2 are coupled in series to the master panel 11. A communication path is therefore provided between the central station 10 and the terminal devices 14, so that any sensing terminal device can send a signal to the central station 10 when it senses the condition which it is designed to detect (or can be monitored by the central station) and the central station can energize any of the alarm devices.

The terminal devices 14 will be located at suitable points throughout the building in which the system is installed; the central station 10 may be located either in a suitable control room in the building or at a remote location.

The Nap Before describing the details of the operation of the system, the general nature of the map will be described. The map is the entire map of the building; only particular parts and aspects of it will actually be displayed on the display unit at any one time. The map is stored in the form of various sets of files, organised in various ways so that the appropriate parts and aspects can be selected for display.

Map Files The map is divided into layers, which will normally correspond to the different floors in the building; only one layer will be displayed at a time.

(It will be realised however that the layers need not correspond strictly to the physical floors of the building; thus a single physical floor could be split into two or more layers, or a single layer could be used for two or more physically distinct floors). For each layer, there are four map files, each of which contains a set of records. These four files are an outline file (OUT), a fill areas file (FLL), a details file (DTL), and a text file (TXT). Each of these files contains a number of records, each record defining a particular entity of the appropriate type for the file (i.e. an outline, a fill area, a detail, and a text string).

The records in the outline, fill, and details files all have broadly the same format. Each record contains a header followed by a number of graphic elements, each element consisting of a set of 6 variables. There are 3 types of element: lines, circles and arcs. The header of the record includes the number of elements of each type, and the elements are stored in type order, so the type of each element is known. The 6 variables of an element define its parameters. Thus for a line element, the parameters are the X and Y coordinates of its start and end and its colour (leaving one variable unused or reserved); for a circle, the parameters are the coordinates of its centre, its radius, and its colour (leaving two variables reserved); for an arc, the parameters are the coordinates of its centre, its radius, its start and end angles, and its colour.Each record in the text files has the format of a text string together with a pair of X and Y coordinates for the start of the text string.

As shown in Fig. 2, the central station 10 includes memories for storing these various files; an outline memory OUT 20, a fill areas memory FLL 21, a details memory DTL 22, and a text memory TXT 23. These memories are coupled to a control and logic unit 25, which is coupled to a display unit 27 for displaying the map. The control unit 25 is also coupled to an interface unit 26 which is in turn coupled to the master panel 11 (Fig. 1), and to a keyboard and mouse unit 28 by means of which it can be controlled.

Device Database In addition to the four map files, there is also a device file or database which contains records of the terminal devices of the system. For each device, there is a record containing 5 elements; the layer in which the devices is located, the X and Y coordinates of the device, the device type (i.e. flame sensor, smoke sensor, alarm sounder, etc.), and a device text. This database can conveniently contain a fixed number of records corresponding to the maximum number of devices which the system can accommodate. (If the actual number of devices is less than this, some of the records will be empty or dummies).

The device database is stored in a device memory 24 which is coupled to the control and logic unit 25 like the memories 20-23.

Control Unit Functionally, the control and logic unit 25 comprises a set of logic units, each of which performs a particular kind of operation. The various logic units are functionally connected so that each can be selected to perform its function and then pass control to another unit. It will of course be realised that in practice, this unit may be implemented structurally by means of various general-purpose circuits, such as registers, arithmetic units, and logic units, and/or a suitably controlled microprocessor.

Nap Display Referring to Fig. 3, the control unit includes image control means comprising an image control unit 30, a layer select unit 31, a region select unit 32, and a scale select unit 33. The image control unit 30 displays a part of the map, scanning through the files in the various memories to obtain the required information for generating the display. This involves drawing the lines defined by the OUT and DTL files, drawing the areas defined by the FLL file (these records must obviously define closed areas), and entering the text strings defined by the TXT file.

The fill areas are not displayed for normal map display; they are selectively displayed in response to alarm conditions and for map generation, as discussed below.

The image control unit 30 operates in conjunction with the layer, region and scale select units. The layer select unit 31 allows the selection of a desired layer; the layer selection may be under operator control for certain purposes, e.g. the generation or updating of the map, or may be under automatic control, e.g. for the display of the location of a fire. The region select unit 32 allows the selection of a desired region of the selected layer; this unit will typically be used to cause the display to be scrolled across the map to the desired region.

The scale select unit 33 allows the scale of the part of the map to be displayed; there may be a choice of several scales (zoom levels).

The contents of the details and text memories are only displayed for the higher zoom levels (larger scales). More generally, further memories could be used (e.g. intermediate level details and fine details) to allow successively finer details to be shown at successively higher zoom levels.

It will be realised that the use of separate memories for (graphical) details and for text is convenient, in that it allows each memory to be organised with the most appropriate record format, but it would be possible to use a single memory for both details and text; this would require the use of two record formats in the same memory, together with a type or format identifier in each record. Similarly, the records for different zoom levels could be included in a single memory provided that the records are coded to define the zoom levels at which they are displayed.

Nap Generation The image control means also includes an image conversion unit 35. This unit operates in conjunction with an external memory 36 (Fig. 2). This external memory can be used to import into the system an image created on some other external system, e.g. a CAD system (not shown). On selection of this external memory, the conversion unit 31 converts the image created thereon into the format used by the present system, and the image control unit 30 displays it on the display unit 27. The operator can then select a desired layer and copy the external image into the outline, fill, or detail memory to form a part of the map for the selected layer.

The image control unit 30 can also be controlled by the operator (via the keyboard and mouse unit 28), to allow the generation of map elements. For this, the map elements include fill areas (which may conveniently be displayed as outlines for this purpose). Once a map element has been generated, it can be added to the appropriate file (memory) if desired. Similarly, map elements (i.e. records in the OUT, FLL, DTL and TXT files) can be deleted under operator control. The map can thus be generated and updated either entirely manually from nothing by using the present system, by importing it from an external system, or by both methods in combination.

Device Mapping The control unit also includes a device mapping unit 40, which operates in conjunction with the device database (in device memory 24) to allow the devices to be placed in the map. Under operator control, for each device in turn a device type is chosen, and the X and Y coordinates of the device are defined. The image control unit 30 automatically selects, for each device type, an appropriate symbol for display on the map.

In addition, the operator can enter a description of the device in the device text element of the device record; the image control unit will then display this device text on the image together with the device image and adjacent thereto. If desired, the device text element may consist of two fields, one for a device description indicative of the device type and the other for "free text" which the operator can enter at will. It is convenient for the device mapping unit to allow copying of the text (or parts of it) from one device record to another together with editing of the text so copied.

Alarm Response If a sensor device detects a dangerous condition, the panel to which it is coupled passes that information to the central station 10. More specifically, the interface 26 includes a buffer which accumulates the device identification (panel identity, loop identity, device identity on the loop, and possibly a text message stored in the panel for the device), alarm condition parameters (e.g. temperature or smoke intensity), and the time from a clock which may be at any convenient location (e.g. in the master panel 11, in the interface 26, or in the control unit 25). The information relating to a device in an alarm condition is termed a message.

When a message is received, a message response unit 45 causes the contents of the message to be displayed on the display unit 27. The message response unit converts the components of the message into a suitable format for the operator to read. To achieve this, it can look up some text identifying the alarm device from the device database 24, add suitable labels identifying the different components of the message, etc. The message is displayed in a message zone on the display device.

When the operator sees the message, they can call up the appropriate part of the map, i.e. that part of the map which contains the device which has initiated the message. The message display unit 45 can provide the initial parameters for obtaining the map i.e. the layer number and the X and Y coordinates - to the image control means automatically, so that the operator does not have to find the appropriate part of the map automatically. But the operator will of course be able to scroll across the map and change the zoom level as desired.

When the map is displayed in response to a message, the message response unit 45 scans through the fill memory 21 to match the layer and coordinates of the device which has initiated the message against the fill records. Each fill area which gives a match i.e. each fill area which includes the device - is passed to the image display control unit 30 for that fill area to be displayed. (Obviously the fill area will be displayed in a filled condition, i.e. as a solid area rather than an outline).

It will be realised that there is a high degree of freedom, in any given layer, in defining the fill areas; in particular, the various fill areas can include different sensor devices and overlap each other to any desired extent. Thus a particular region of the map can be shared by two or more fill areas, and will then be highlighted when any of those fill areas is displayed, i.e. in response to a variety of different sensors. Similarly, a single sensor can cause several different fill areas to be highlighted.

If desired, the actuator devices may be controlled from the control and logic unit 25 as well as, or instead of, from the panels as described above.

For this, the device database would contain, for each sensor device, control messages in addition to the other information discussed above. On a sensor device detecting an alarm condition, an actuator control logic unit (not shown) in the control and logic unit would extract the control messages for that device from the device database and transmit them through the interface 26 to the panels 11, 12-1, and 12-2, which would then actuate the required actuator devices.

Nessage Queueing In the event of a fire, it is of course likely that dangerous conditions will occur at several sensor devices, at slightly different times, as the fire develops. The system therefore incorporates queueing means for responding to several successive messages.

(Although two terminal devices may of course detect alarm conditions simultaneously, the transmission path from the devices through the panels to the central station forces the corresponding messages to occur in sequential order).

There are two message memories coupled to the control unit 25, a sequential memory 40 and a priority memory 41 (Fig. 2). The message response unit 45 causes incoming messages to be stored in the sequential memory 40 in order of receipt and in the priority memory in order of priority.

From the priority memory 41, relative priorities have to be assigned to the sensor devices. In the present system, these priorities are defined by the sensor type; thus flame sensors may be assigned the highest priority, smoke sensors the next highest priority, and manual alarms the lowest priority, and with all sensors of the same type having the same priority. An incoming message can then be inserted into the right place in the priority memory 41 by scanning own the list of messages in the memory until a message of the same or lower priority is found, and inserting the new message into the sequence immediately above that message.

It will of course be realised that more elaborate priority systems can be implemented if desired. For example, the device records in the device database memory 24 can include device priorities. The device priority for an incoming message can then be looked up from the device database 24 by the message response unit 45 and added to the message to allow the message to be inserted at the appropriate position in the list of messages in the priority memory 41.

The message response unit 45 can also be controlled by the operator to scan through either of the message memories 40 and 41, to select particular messages for display. In normal circumstances, the operator would scan through the priority memory 41, to inspect the messages in order of priority.

The operator can also use the message response unit to delete messages from the priority memory 41. If this memory becomes full and overflows, messages with the lowest priority will be lost. For the sequence list memory 40, the operator can scan through this memory but cannot delete messages therefrom. If this memory becomes full, the oldest messages therein will be transferred to an archive file (not shown).

Claims (5)

CLAIMS:

1. A graphical display system for displaying a map of a fire alarm system, wherein the map has a number of fill areas and, when a sensor device detects an alarm condition, the map is displayed with all the fill areas within which that device is located are displayed.

2. A graphical display system according to Claim 1, wherein the map is stored in a plurality of building structure records each representing a structural feature of the building, a plurality of device records each representing the location of a terminal device of the alarm system of the building, and a plurality of records each representing an area of the building.

3. A graphical display system according to either previous claim, wherein each of the records includes a layer value, so that any desired layer of the map can be displayed.

4. A graphical display system according to any previous claim, wherein at least some of the records have distinctive characteristics corresponding to different levels of detail and records for a higher level of detail are not displayed.

5. A graphical display system for a fire alarm system which sends a message when a sensor detects an alarm condition causing the display of the map with the corresponding sensor indicated, and including message storage means comprising a sequential list memory, a priority list memory, and means for storing message in the sequential list memory in temporal order and in the priority list memory in order of relative priorities of the devices associated with the messages.