The present invention generally relates to process control systems. More particularly the present invention relates to a method, video control arrangement and a computer program product for determining objects present in a process control system.
A process control system normally comprises a number of process control objects involved in the control of the process.
The process control system does then typically comprise control computers as well as work stations or monitoring computers via which operators can monitor the process. The work stations are then typically provided in a control room.
It is also customary to have video cameras installed at locations around the process control objects. The cameras capture video images that are streamed to the control room for being observed via the monitoring computers. The operators can then view the video streams on the screens of their monitoring computers and order the cameras to view a particular object. This is possible as the video cameras will change both the angle and zoom to view different objects. Typically the objects are then known in relation to the camera views through having been pre-configured to fit the position of each process control object.
US 2011/0199487 describes video cameras in a process control system or an automation system where a determination is made of which cameras are in line of sight with an object and also various ways to focus and steer cameras to objects.
Video cameras can also be used in relation to security such as for ensuring that an operator does not come too close to a dangerous machine or process. This is described in EP 1061487.
US 2011/0200245 describes the viewing of objects and activities within a manufacturing area as well as detecting of objects (RFID tags) in scanned area. The images are used in manufacturing control functions, comprising an automation control function, a logistics control function, a safety control function and a quality control function. The automation control function uses the images in order to determine how and/or when machines and assembly equipment should be indexed or controlled.
There are a number of problems associated with the above-mentioned use of video cameras.
For each object that an operator wants to view in a video stream, the parameters must be configured to enable the video camera to show the relevant object. If a camera is moved, i.e. placed in another location, the parameters have to be reconfigured. If a new object is added in front of the camera, this object may also have to be manually added to the process control system.
Operators may also want to see live images of all objects, but as it requires a lot of manual work to configure a new object this may not be done. In such views there is furthermore no identification available to ensure which process control object is shown. There is no guarantee that the video stream is showing the correct object as the configuration could have been performed incorrectly.
The present invention is provided for solving one or more of the above described problems.
The present invention addresses the problem of determining objects being captured with video cameras in a process control system. The invention is more particularly directed towards improving this type of determination.
This object is according to a first aspect of the invention solved through a method of determining objects present in a process control system, the method being performed by a video control arrangement and comprising the steps of:
This object is according to a second aspect of the invention solved through a video control arrangement for determining objects present in a process control system, the video control arrangement comprising:
This object is according to a third aspect of the invention solved through a computer program product for determining objects present in a process control system, the computer program product being provided on a data carrier comprising computer program code configured to cause a video control arrangement to, when the computer program code is loaded into at least one device providing the video control arrangement, order a group of video cameras, comprising at least one video camera, to repeatedly scan an area in order to obtain a set of video streams, determine if there are any new objects associated with the process control system in the area through detecting object identifiers of objects in the video streams,
The present invention has a number of advantages. There is no need to manually program the video cameras to know the location of process control objects as these are automatically determined. There is also no need for reconfigurations of cameras. There is thus no extra work needed if a camera is moved or replaced. If an object known to the process control system but previously not detected in the scanned area is detected in front of one of the video cameras, this object will automatically be reported to the process control system, which system may then update known locations of the object accordingly. The invention also provides cost savings since there is no need for configuring the location of each process control object. There is furthermore no effort involved with the configuring of a new video camera.
The present invention will in the following be described with reference being made to the accompanying drawings, where
In the following, a detailed description of preferred embodiments of a method, data presentation control arrangement and a computer program product for determining objects present in a process control system will be given.
In
There is furthermore a second data bus B2 and between the first and second data busses B1 and B2 there are connected a server 18 providing control and protection of the process and a database 20 where data relating to control and protection of the process is stored. Such data relating to control and protection may here comprise process data such as measurements and control commands, while data relating to protection may comprise alarm and event data as well as data on which alarms and events can be generated, such as measurements made in the process. There is furthermore a process control server 22 connected between the two buses B1 and B2.
To the second data bus B2 there is also connected a number of further devices 24, 26, 28 and 30. These further devices 24, 26, 28 and 30 are field devices, which are devices that are interfaces to the process being controlled. A field device is typically an interface via which measurements of the process are being made and to which control commands are given. Because of this the field devices are furthermore process control objects. In one variation of the invention a first field device is a first process control object 24, which as an example is a tank.
In the program memory 44 there is provided software code which when being run by the processor 42 forms a an object determining unit 46 and a view determining unit 48.
A first embodiment of the invention will now be described with reference also being made to
The invention will now be described in relation to the first group of video cameras. It should however be realized that all groups may operate in the same manner.
All process control objects 24, 26, 28 and 30, which are typically stationary objects, are provided with object identifiers 51, such as optically readable identification tags. These may be barcodes, like one- or two-dimensional bar codes. In this way they can be identified using the video cameras of the video control arrangement 31. However, also other objects in the system such as mobile objects like maintenance engineers and vehicles such as fork lifts may be provided with such object identifiers. In
As outlined in
The object determining unit 46 analyses the video streams in order to see if there are any object identifiers in them. The object determining unit 46 thus detects object identifiers of objects in the various video streams, step 56. It may here as an example detect the object identifier 51 of the first process control object 24 as well as the object identifier 53 of the maintenance engineer 52. It may thus detect the bar codes of object identifiers that appear in the line of sights or views of the video cameras when scanning. It may also detect the position of the object. This detection may be made based on a known location of the video camera, the angle(s) of the scan when the object is detected as well as through a determination of the distance between the video camera and the object.
In the memory 44 there may furthermore be stored the identifiers of previously detected object identifiers, which known identifiers the object determining unit 46 compares with the newly detected object identifiers. In case the detected identifiers are already known, step 58, then the object determining unit 46 waits until it is time for a new scan and then again orders the video cameras 32, 34, 35 and 36 to perform scanning, step 54. If the first process control object 24 was identified in a previous scanning, the identifier 51 would be handled in this way.
However, in case any detected identifier is not previously known, step 58, then it is reported to the process control server 22, step 60, which server 22 may thereby be notified of the presence of a process control object or some other object related to the process being in the area A. Also the position may be reported. The process control server 22 can then act upon this knowledge. The detected identifier may also get stored in the memory 44 together with previously detected object identifiers.
The scanning may be set to start as soon as the video cameras are installed. This means that the method may be used for determining the objects covered by the video cameras without pre-defining objects in video camera views. This also means that initially there may be no identifiers stored in the memory 44. As an alternative it is possible that some objects are known and that their identifiers are stored in the memory.
The video streams may also be presented, through operator selections, via the display of the monitoring computers 12 and 14. The operator may for instance select an object via process graphics on the monitoring computer and then one or more video streams of video cameras via which an object has been identified.
It is possible for the operator at the monitoring computers 12 and 14 to use the video cameras in different ways depending on if the objects are regular process control objects or some other temporarily present objects.
Because of this the object determining unit 46 analyses the recorded video streams VS to see if any of the new objects are stationary or moving. If they are stationary, step 62, then they are registered as process control objects, step 64, and this fact may also be reported to the process control server 22. This is then again followed by a new scan according to the schedule, step 54. The registering may here involve registering which objects are visible via specific video cameras. It is also possible to register at which angles they are visible as well as the position.
It is furthermore possible that a previously identified and registered object is no longer possible to identify in a scan of the area A. In this case it is possible for the object determining unit 46 to de-register the object and inform the process control server 22 of the object no longer being present in the area A as well as possibly to inform of the last known position of this object.
If however the objects are not stationary, but mobile, step 62, it is possible for the operators at the monitoring computers 12 and 14 to select to follow an object. It is for instance possible to determine that an object is mobile through the object having a movement that deviates from the movement caused by the video camera performing the scanning. Therefore if the object determining unit 46 receives an instruction to follow a mobile object, step 66, such as to follow the maintenance engineer 52 with identifier 53, then the video cameras are ordered to follow the object, step 68. It can thus be seen that it is possible to lock onto this object with the video cameras. This may involve following the object from the first room to the second room and may thus involve also the fifth camera 37 following the maintenance engineer 52 if entering the second room. In case there are further video cameras in the second and the third room, it is of course also possible to follow the “object” further.
In both cases, whether the object is to be followed or not, the object determining unit 46 investigates if the object is in a restricted area. If for instance the object identifier is deemed to be associated with a human and the first process control object contains a chemical substance that is toxic, then it is possible that the human is not allowed to be too close to the first process control object 24.
If the mobile object is deemed to be within a restricted area, step 70, then the object determining unit 46 may generate an alarm, step 72, which may be presented to the operator via a monitoring computer 12 or 14. The alarm may also be forwarded to the process control server 22. If the mobile object 52 is not in the restricted area then the object determining unit 46 awaits the performing of the next scan, step 54.
It can thus be seen that it is possible to follow or lock to a mobile object and if this object, as it is being followed, enters a restricted area, then an alarm is generated.
It is also possible for the operator to make selections of how the stationary process control objects are to be viewed. Such selections are handled by the view determining unit 48. The view determining unit 48 may receive an operator selection of a combination of registered process control objects to be viewed, step 74. The operator may for instance perform a logical object combination in the form of (A and B) not (C and D), where A, B, C and D denote different process control objects. Such a logical combination may specify that the operator desires to view the process control objects A and B, but not process control objects C and D.
The view determining unit 48 thus analyses the operator selections and then selects a video camera and perhaps also a video camera angle that best fulfills the combination selection, i.e. which best meets or is closest to the operator requirements of objects that are desired to be viewed (and not viewed). The camera angle may be a camera angle in a horizontal position and/or an angle in a vertical direction.
A video stream from a selected camera can thus be presented to the operator. It is possible to link further data to an object in a video stream, such as a face plate and process control data of the object such as process measurements. This linking to the object would then be made based on the object identifier and may be accessed by the operator through selecting the object as it is being presented in a video stream. The object determining unit may in this case receive such a user selection and provide a pointer to the corresponding further data, which the monitoring computer may then fetch from the process control system.
The invention has a number of advantages. The video cameras may automatically detect and identify objects in their view. By continuously tracking objects in the picture frames of the video streams, the video cameras will detect identification tags of plant devices or process control objects (such as pumps, tanks or temperature sensors), plant personnel and mobile plant equipment (such as forklifts). Whenever a new object is detected and identified, the process control system will be informed about this object.
As was discussed above, the automatic object identification could be used in a variety of ways:
The following use case scenario can occur when using the invention:
1. A new video camera 32 is mounted on the wall of the first room.
2. The video camera 32 is, when idle, continuously scanning (by movements) the environment for any object identifiers.
3. Whenever an object identifier is found, the information is uploaded to the process control server 32. No manual configuration is needed.
4. Operator Nick just obtained an alarm from Tank 24. Before Nick orders maintenance assistance he wants to confirm the tank status from the video cameras.
5. He selects the tank from the process graphics on his operator screen 12 and requests a list of all video camera views that contains the tank 24.
6. A list of video camera views, populated from the video cameras themselves, is then seen on the screen. All different views contain the tank 24.
7. Nick browses through all the video camera views to get a good understanding of the tank 24.
8. Suddenly Nick receives an alarm, which indicates that Nina 52 just entered a restricted area.
The alarm is triggered by a camera that has detected the object identifier 53 of Nina 52.
This invention thus allows:
Several further benefits can be listed for this invention:
The object determining unit and view determining unit were above described as being implemented in a video control server of the process control system. They may as an alternative be provided in one or more of the video cameras. These units may thus be provided in the logic of the video cameras.
The object determining unit and view determining unit may furthermore both be provided in the form of one or more processors together with computer program memory including computer program code for performing their functions. As an alternative they may be provided in the form of an Application Specific Integrated Circuit (ASIC) or Field-Programmable Gate Array (FPGA). This computer program code may also be provided on one or more data carriers which perform the functionality of the present invention when the program code thereon is being loaded into an object determination server or the logic of a video camera. One such data carrier 78 with computer program code 80, in the form of a CD ROM disc, is schematically shown in
The invention can be varied in many ways. Objects were for instance described as being detected via object identifiers in video streams. It is possible with other types of detection. A video camera may for instance be provided with a near field communication reader (NFC) reading an NFC tag on objects. It is also possible to determine a position to which a camera is pointing for instance through using Global Positioning System (GPS) or wireless communication networks and obtain data about objects at these positions in various ways. Moving objects, such as people, may then be identified through mobile terminals, like mobile phones, that they are equipped with and the presence of process control objects may be obtained through investigating a database with positions about these objects. It can therefore be seen that the present invention is only to be limited by the following claims.
Number | Date | Country | Kind |
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12176383.3 | Jul 2012 | EP | regional |
Filing Document | Filing Date | Country | Kind |
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PCT/EP2013/062101 | 6/12/2013 | WO | 00 |