SYSTEM AND METHOD FOR SCHEDULING AN AUTOMATION PROCESS CONTROLLING A MACHINE
1. System for scheduling an automation process controlling a machine, comprising:
- a parser module for parsing calendar data, the calendar data comprising calendar events including clock data and task data;
a clock module for monitoring time instances and triggering the parser module to parse the calendar data to retrieve the task data of a calendar event that is identified by clock data corresponding to a time instance;
a task module for processing the task data of the calendar event to obtain machine control data for execution on a machine.
A system and a method for scheduling an automation process controlling a machine. The system including a parser module for parsing calendar data, the calendar data comprising calendar events including clock data and task data. The system further including a clock module for monitoring time instances and triggering the parser module to parse the calendar data to retrieve the task data of a calendar event that is identified by clock data corresponding to a time instance; and a task module for processing the task data of the calendar event to obtain machine control data for execution on a machine.
- 1. System for scheduling an automation process controlling a machine, comprising:
a parser module for parsing calendar data, the calendar data comprising calendar events including clock data and task data; a clock module for monitoring time instances and triggering the parser module to parse the calendar data to retrieve the task data of a calendar event that is identified by clock data corresponding to a time instance; a task module for processing the task data of the calendar event to obtain machine control data for execution on a machine.
- View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
- 12. Computer implemented method for scheduling an automation process controlling a machine, comprising:
exchanging calendar data between a client device and a machine; parsing the calendar data to retrieve calendar events defined by clock data and associated task data; monitoring time instances and for clock data of a calendar event matching a time instance; processing the associated task data of the calendar event to obtain machine control data, and transmitting the machine control data for execution on the machine.
- View Dependent Claims (13, 14, 15)
The present invention relates to a system for scheduling an automation process that controls a machine, and a method for scheduling such an automation process. In particular, the invention relates to a system for scheduling the operation of an industrial automation system that is controlled by an automation process.
Industrial automation systems are provided to perform, control and supervise industrial processes. Industrial processes employ Programmable Logic Controllers (PLC) and other automation devices to implement such control. The control includes the programming of the machines and systems for performing the industrial processes. Which is usually done through ERP systems, SCADA systems or other centralized systems. These systems are costly and difficult to set up and manage. In particular, with regard to a simple machinery and processes, the cost and effort of such systems do not justify the use thereof for small sized companies.
Scheduling and planning tasks is also desired for small enterprise, such as for example a bakery starting up its'"'"' oven at 05:00 AM in the morning or a crop farm watering its'"'"' field at dawn. The usual way to deal with such events in a PLC is to develop a PLC application that checks the internal date and time of the PLC. Which is complex to program and does not provide the look and feel of a planned activity. For example, machine builders may design the same kind of machinery for several customers. But if the machine has to perform a specific action or task at certain scheduled events, such as daily or weekly, the machine builder needs to adapt the machine PLC application according to that particular customer requirement. Accordingly, it is complex for a machine builder to manage such schedules. Neither is it user friendly for a final end user, for example when the schedule of managed events varies a lot or depends on holidays, non-working days, and/or weekends.
It is an object of the invention to alleviate the manner in which an automation system may be scheduled to perform an automated process. Thus, to provide an industrial system that may be scheduled in a more simple and direct manner.
According to the invention, this object is achieved by providing a system for scheduling an automation process controlling a machine, the system including a parser module for parsing calendar data, the calendar data comprising calendar events including clock data and task data. The system further including a clock module for monitoring time instances and triggering the parser module to parse the calendar data to retrieve the task data of a calendar event that is identified by clock data corresponding to a time instance; and a task module for processing the task data of the calendar event to obtain machine control data for execution on a machine.
In another aspect, the invention relates to a computer implemented method for scheduling an automation process controlling a machine, the method including: exchanging calendar data between a client device and a machine, parsing the calendar data to retrieve calendar events defined by clock data and associated task data, monitoring time instances and for clock data of a calendar event matching a time instance processing the associated task data of the calendar event to obtain machine control data, and transmitting the machine control data for execution on the machine.
The system and method as disclosed allows a first operator using client device 7 to have credentials to only be allowed to interact with the calendar data of a first control device, whereas a second operator or supervisor using client device may have credentials to be allowed to interact with the calendar data of both the first and a second control device. Other ways of differentiating user rights, as known with regard to calendar management, such as delegation or read-only permission, may be set up using the invention as disclosed.
IEC standard RFC5545 and its'"'"' update versions 5546/6868/7529 describe a format for representing and exchanging calendar data across platforms independent of any particular calendar service or protocol, also known as iCalendar. The calendar data may include calendaring and scheduling information such as events, to-do'"'"'s, journal entries, and free/busy information. The iCalendar format may be advantageously used in a system as disclosed herein.
Further aspects, effects and details of the invention are described in the following detailed description of a number of exemplary embodiments, with reference to the drawings.
By way of example only, the embodiments of the present disclosure will be described with reference to the accompanying drawing, wherein:
As one possible example of a format for calendar data the Event Title may define the automation task to be performed and the Event Body may define a recipe, parameters, and other necessary details. A recipe herein refers to a combination of partial tasks i.e. steps and parameters to be used for each step.
The clock module 3 is configured for monitoring time instances i.e. keeping time. The clock module 3 is further configured to periodically check the parser module 2 for calendar events of which the clock data corresponds to specific time instances and keep track of any identified time instances. The clock module 3 is further configured to trigger, at a particular identified time instance, the parser module 2 to parse the calendar data of the calendar event that is identified by the clock data of the corresponding time instance. The parsing of calendar data serves to retrieve the task data of the calendar event.
In this example, the clock module is arranged for keeping an internal time independently by means of, for example, an internal oscillator generating a periodic clock signal. In other examples, the clock module may retrieve time indications from an external time indicator provider, such as for example a periodic clock signal from an external source or a time value from an external clock. In yet another example, the clock module may be synchronizing the internal time with an external time signal.
The task module 4 is configured for receiving the task data of the calendar event, processing the task data, and transmitting machine control data such as signals and/or messages in accordance with the task data. For example, the task data may be taken from the header of the calendar event “turn on watering” which then needs to be translated into the required machine operations. The machine control data is transmitted to a control device 5 performing control of the automation process, in this example a Programmable Logic Controller PLC.
The system 1 of
An operator of the automation process may interact with the system 1 via a calendar application 6 on a client device 7. The system 1 is arranged for exchanging calendar data with the client device 7. This may be set up and managed through the parser module 2 or it may be mediated directly by allowing the calendar application 7 direct access to the storage module 8. The client device 7 may be any kind of device capable of providing a machine-user interface, such as SCADA or HMI, and/or a smartphone, tablet or personal computer. The calendar application may take the form of any suitable program, such as a website or webpage, an MS Outlook/Exchange calendar, a calendar application based on Android, Linux or other operating system, a mobile phone calendar application or even just an HTML based web application. Basically, the calendar application may be any program employing a calendar protocol, and more preferably the iCalendar protocol.
Furthermore, the calendar data may contain a calendar event containing task data that triggers the system to retrieve new calendar data from an external server, cloud infrastructure or other remote source. Thus, instead of an operator interacting directly with the storage module pushing new data, the system itself may initiate updating the calendar data.
In addition, the scheduling system may be arranged for sending calendar updates to an operator or user by means of SMS, eMail or any other suitable messaging platform.
In another example, shown in
One way for implementing authentication policies is by means of a key infrastructure using public and private keys; though other means may be considered. In case of machine-to-machine i.e. PLC-to-PLC communication, a first machine may access and amend calendar data of a second machine directly if it promptly authenticates itself. Or the first machine may provide an entry for calendar data as part of an email to the second machine being the owner of the calendar data.
Furthermore, the system 1 may be arranged for scheduling an additional automation process controlled via a second control device 9. The system 1 may be configured to allow presentation of the calendar data of the two distinct automation processes as separate calendars. This may be achieved via the storage module 8 storing the calendar data of two or more automation processes separately. Or it may be achieved by the credentials module 10, the storage module storing all calendar data jointly, and the credentials module 10 separating or splitting the calendar data according to the user and/or service credentials. In addition, the calendar application 6 of the client device 7 may identify and handle the calendar data as separate calendars, allowing to show the calendars individually, next to one another, in overlay or any other suitable known manner for displaying calendar information.
In another example, shown in
The systems 1, 11 may be implemented on a server, which then connects to control devices 5 and/or 9. The systems 1, 11 may also be implemented as part of such control devices, thus within the PLC 5, 9 or a Real Time Operating System RTOS. The system 1, 11 may further be implemented as stand alone, only allowing access on local premises or it may be implemented using a cloud infrastructure. Furthermore, the various modules of the system may also be distributed as various firmware modules or hardware components.
As an alternative, or even in addition to the client device interacting with one of the scheduling systems, one of the PLCs may also be set up to interact with the scheduling system of the other PLC. As shown in the example in
An example of a distributed system is shown in
For sake of completion, in this example it is shown that as a final step the machine control data is executed 106 on the machine that is controlled by the automation process.
In some embodiments, the moment of transmitting 105 the machine control data may follow directly on finishing the processing 104 of the task data, in which case the time monitoring will trigger the processing the task data of a calendar event at the exact time of the matched clock data. In other embodiments, the moment of transmitting the machine control data may be the time instance that matches the clock data of the calendar event, in which case the task data is fetched for processing ahead of the time instance that matches the clock data.
The method may be implemented on a server, which then connects to control devices of a machine. The method may also be implemented as part of such control devices, thus within e.g. a PLC. Or it may be executed as program on a Real Time Operating System RTOS running on a PLC or a desktop PC being connected to a machine. The method may be implemented as stand alone, only allowing access on local premises or it may be implemented using a cloud infrastructure. Furthermore, the various modules of the system may also be implemented as software objects and distributed over various hardware components as mentioned above.
For programming of sequential controls systems, such as PLC devices and systems based thereon, various IEC standardized languages are available such as Ladder Logic, Structured Text and Instruction List. Also Sequential Function Charts SFC have been established as an adequate instrument for design and implementation of process flow control. Programming standard IEC 61131-3 for example describes a graphical implementation of Sequential Function Charts for programming PLCs. In the following example, it will be described how the disclosed system and method allow to convert an SFC into calendar data and vice versa, thus providing a direct link between calendar data and the control program of a PLC.
In the calendar, the event showing the result may have a certain color as an indication of success or failure; a familiar color coding would e.g. include green and red. More in general, any event shown in the calendar may be shown in a particular color as a visual indication to the user.
In order to perform the actions of the automation process according to the schedule stored in the calendar data, and as visualized by the calendar representation of
The SFC starts at Step Check next Event 20, which checks for a next event in the calendar data. If no event is recognized, the value EventDetected=NoEvent, as indicated by transition 21. Together with the value for Watering, which may be OFF or On, NoEvent forms a condition set for a further three possible transitions 22, 23, 24. In case of NoEvent and Watering=OFF, the next Step is Wait 25. From Wait 25 the only possible transition 26 depends on the condition of a time lapse of 1 second, on the expiration of which Step Check next Event 20 is activated again.
In case of NoEvent and Watering=ON, two transitions 23, 24 are possible, depending on a third condition indicating whether a problem occurred, thus status=Problem or NoProblem. If no problem occurred during watering for 2.5 hours i.e. 9000 seconds, transition 23 leads to Step Add success Result 27. This step will turn off the watering and will add a calendar event to the calendar data indicating the amount used for watering the crop field and an indication to show that result in e.g. green. If a problem does occur, for example due to a lack of water supply, the system will generate an alert indicating the occurrence of that problem. Then the condition set NoEvent, Watering=ON, and Problem of transition 24 leads to Step Add fail Result 28. Step Add fail Result 28 will also turn off the watering and will add a calendar event to the calendar data indicating the amount used for watering the crop field and an indication to show that result in e.g. red, indicating the failure. From both Step 27 and 28 the system will move via transition 29 back to Step Check next Event 20.
At Step Check next Event 20, in case an event is recognized, the EventDetected=yes fulfills the condition of transition 30 leading to Step Analyze event Data 31.
The recognized event may be the weather forecast retrieved at 02:00 AM forecasting a sunny day or a rainy day. Thus, depending on the event title being Weather.Sunny or Weather.Rainy, the system will move via transition 32 to Step enable Watering 33 or via transition 34 to Step disable Watering 35; which steps will respectively enable or disable the watering system.
The recognized event may also be the event Watering intended to start at 03:00 AM and to continue for 2.5 hours till 05:30 AM. In that case the event title watering will fulfill the condition of transition 36 and result in Step Turn watering ON 37.
Finally, from each Step 33, 35, and 37 the system will move via transition 29 back again to Step check next Event 20.
In the above example for watering a crop field, it is shown how the same calendar data may both be visualized as a calendar representation and be processed into machine control data for providing the required actions, parameters and values to be executed by the automation process controlling the machine.
As can be seen in the SFC example, the Step Check next Event 20 is a cyclic task that periodically checks for new events in the calendar data. Accordingly, the clock module 3 of the disclosed system for scheduling an automation process not only keeps time and monitors the time instances, but also orchestrates the time dependent behavior of the system by triggering the parser module 2 to retrieve the scheduled actions at the appropriate time instance. Similar considerations apply to the disclosed method.
Accordingly, the scheduling system preferably has the parser module and the task module running as individual processes. As this allows to exchange the calendar data as an autonomous repetitive process in parallel to the task module processing a current calendar event.
Thus far, the system and method for scheduling an automation process controlling a machine have mainly been described as in operation during run time. Prior to this, during a phase commonly referred to as build time, the system is prepared in order to be able to set up and configure the system and machine for operation. Accordingly, in build time an interface is available to configure the calendar, the user accounts and user rights. This will also set which automation actions to perform in response to the calendar events managed. Furthermore, this will set which dedicated calendar function blocks are to be included in the automation application in order to perform various functions. These function blocks may include:
- Synchronize: to synchronize calendar data between client device and scheduling system or between scheduling systems
- Add Event: to add an event to calendar data
- Get Event (Free): retrieve event of specified date and time
- Import Holidays: retrieve holiday events from an external source of calendar data
- Export Calendar: provide the system calendar data to client devices or other systems
- Get Action List: retrieve list of available tasks that may be scheduled as calendar event
- Look next event to do: look up the calendar event first up
- Send event per eMail/SMS: exchange calendar data or event by means of eMail or SMS
The examples of system and method as described thus far, may take advantage of the platform independency of the iCalendar protocol for exchanging calendar data. Accordingly, different PLCs running different Operating Systems or even a single PLC running multiple different Operating Systems, e.g. having multiple cores or within a Virtual Machine environment, can easily exchange calendar data across these platforms.
Thereto, the task data of a calendar event includes a script, such as e.g. a Node-Red script, which will instruct the scheduling system 51 to load the script onto an embedded webserver 60 and execute. Execution of the script then retrieves the application program from a remote and secure storage 61, such as a local on-premise server, and deploys the retrieved application program on the PLC 55.
Thus, when the parser module 52 is triggered by the clock 53 to parse the calendar data into task data, the task module 54 continues by processing instructions present in the task data. The instructions indicating to load the script onto the appropriate embedded webserver 60. And the webserver 60 by executing the script retrieves the application program for the PLC 55 from database 61. In this example, the webserver 60 is presented as embedded within the scheduling system. In other examples, it may be embedded independently on the same device as the scheduling system.
So, in this example the task data does not merely contain instructions to be converted by the task module into process automation data, as in previous examples. Moreover, the task data may include only This enables to reduce the amount of conversion required and thereby relieves the scheduling system of processing part, or even all, of the calendar data into a sequential programming language. Furthermore, it allows to dispatch PLC application programs in a timely fashion to a particular PLC.
In particular, when manufacturing machines or other devices containing PLCs that are to be customized for different uses, a controller, such as an edge controller, including the scheduling system is enabled to deploy different application programs to different PLCs. As for the manufacturing process it may be known which machine and associated PLC is produced at which moment. Thus, synchronization of the manufacturing process of the machine with the deployment of the intended PLC application program becomes possible.
Although the present invention has been described above with reference to specific embodiments, it is not intended to be limited to the specific form set forth herein. Rather, the invention is limited only by the accompanying claims and, other embodiments than the specific above are equally possible within the scope of these appended claims. For example, a laundry shop exploiting various washing machines may equip a scheduling system as described to indicate which washing machines are in use or unused. A customer may than remotely reserve a time slot for a particular washing machine. When the laundry is loaded in the washing machine, the customer may leave and will be informed via the calendar application of his smart phone when the laundry washing program will be ready.
Furthermore, although exemplary embodiments have been described above in some exemplary combination of components and/or functions, it should be appreciated that, alternative embodiments may be provided by different combinations of members and/or functions without departing from the scope of the present disclosure. In addition, it is specifically contemplated that a particular feature described, either individually or as part of an embodiment, can be combined with other individually described features, or parts of other embodiments.