Automatic Configuration of Synchronous Block Execution for Control Modules Run in Fieldbus Networks

• US 20080249641A1
• Filed: 12/31/2007
• Published: 10/09/2008
• Est. Priority Date: 09/29/2006
• Status: Active Grant

• Current Assignee: Fisher-Rosemount Systems Incorporated (Emerson Electric Company)
• Original Assignee: Fisher-Rosemount Systems Incorporated (Emerson Electric Company)
• Inventors: Lucas, John M., Enver, Alper T., Ramachandran, Ram, Tanyous, Ebtesam S., Krivoshein, Kenneth D., Christensen, Daniel Dean
• Granted Patent: US 8,005,553 B2
• Time in Patent Office: Days
• US Class Current: 700/9
• CPC Class Codes: G05B 19/042 using digital processors G05B19/05 takes precedence
• CPC Class Codes: G05B 19/4185 characterised by the network communication
• CPC Class Codes: G05B 2219/1134 Fieldbus
• CPC Class Codes: G05B 2219/25229 Partition control software among distributed controllers
• CPC Class Codes: G05B 2219/25232 DCS, distributed control system, decentralised control unit
• CPC Class Codes: G05B 2219/31121 Fielddevice, field controller, interface connected to fieldbus
• CPC Class Codes: G05B 2219/32248 Create schedule from elementary operations from database
• CPC Class Codes: Y02P 90/02 Total factory control, e.g. smart factories, flexible manufacturing systems [FMS] or integrated manufacturing systems [IMS]

Abstract

A method or apparatus automatically configures a control module for synchronous execution on a Fieldbus segment of a process control network by determining if all of the critical function blocks of a particular control module can be assigned to FOUNDATION® Fieldbus field devices or to the I/O device associated with a particular Fieldbus segment. If so, the method or apparatus automatically assigns the function blocks of the control module, which would otherwise be scheduled to execute in a controller, to the I/O device for the Fieldbus segment. This technique enables all of the critical or necessary function blocks within the control module to execute in one macrocycle of the Fieldbus segment, thereby executing synchronously on a Fieldbus segment. This operation, in turn, increases the overall execution rate of the control module with respect to control modules that have function blocks split between a controller and field devices on a Fieldbus segment, which has been the traditional manner of configuring control modules implemented using devices on a Fieldbus segment.

Claims

1. A system operable on a processor for automatically assigning function blocks of a control module to be executed in devices within a process control network, the process control network having a process controller communicatively coupled to an input/output device which is connected to one or more field devices via a data bus, the system comprising:

a computer-readable memory;

a routine stored on the computer-readable memory for execution on the processor, wherein the routine, when executed on the processor;

determines a set of function blocks disposed on a forward flow path of the control module, the set of function blocks including an input function block, an output function block and one or more intermediate function blocks;

determines if each of the input function block and the output function block on the forward flow path of the control module is assigned to execute in the one or more field devices on the data bus; and

assigns the one or more intermediate function blocks on the forward flow path of the control module to execute in the input/output device if both the input function block and the output function block on the forward flow path of the control module are assigned to execute in the one or more field devices on the data bus.

2. The system of claim 1, wherein the routine, when executed on the processor, assigns each of the one or more intermediate function blocks on the forward flow path of the control module to execute in the process controller if one or more of the input function block and the output function block on the forward flow path of the control module is not assigned to execute in any of the one or more field devices on the data bus.

3. The system of claim 1, wherein communications occur over the data bus according to a pre-established communication schedule, and wherein the routine, when executed on the processor, further schedules each of the input function block, the output function block and the one or more intermediate function blocks to operate synchronously within the pre-established communication schedule.

4. The system of claim 3, wherein the pre-established communication schedule includes a repeating macrocycle, and wherein the routine, when executed on the processor, schedules each of the input function block, the output function block and the one or more intermediate function blocks within the pre-established communication schedule by creating a macrocycle for the data bus in which each of the input function block, the output function block and the one or more intermediate function blocks is scheduled to communicate over the data bus at least once during each macrocycle.

5. The system of claim 3, wherein the routine, when executed on the processor, schedules one of the input function block, the output function block and the one or more intermediate function blocks to execute at a faster rate than another one of the input function block, the output function block and the one or more intermediate function blocks.

6. The system of claim 5, wherein the routine, when executed on the processor, further creates a macrocycle for the pre-established communication schedule in which the one of the input function block, the output function block and the one or more intermediate function blocks is scheduled to operate more times during the macrocycle than the another one of the input function block, the output function block and the one or more intermediate function blocks.

7. The system of claim 5, further including an indicator for at least one of the function blocks of the control module that specifies a multiplier, the multiplier indicating a relative rate of execution for the at least one of the function blocks of the control module, and wherein the routine, when executed on the processor, uses the indictor to schedule the one of the input function block, the output function block and the one or more intermediate function blocks to execute at a faster rate than the another one of the input function block, the output function block and the one or more intermediate function blocks.

8. The system of claim 1, further including a user-settable property associated with the control module indicating whether the function blocks of the control module can be assigned to the input/output device, and wherein the routine, when executed on the processor, assigns the one or more intermediate function blocks on the forward flow path of the control module to execute in the process controller if the user-settable property of the control module indicates that function blocks of the control module should be not be assigned to the input/output device, even if both the input function block and the output function block on the forward flow path of the control module are assigned to execute in the one or more field devices on the data bus.

9. The system of claim 1, further including a user-settable property associated with the input/output device indicating whether function blocks of any control module can be assigned to the input/output device, and wherein the routine, when executed on the processor, assigns the one or more intermediate function blocks on the forward flow path of the control module to execute in the process controller if the user-settable property of the input/output device indicates that function blocks should be not be assigned to the input/output device, even if both the input function block and the output function block on the forward flow path of the control module are assigned to execute in the one or more field devices on the data bus.

10. The system of claim 1, wherein the routine, when executed on the processor, checks to determine whether the input/output device supports each of the one or more intermediate function blocks on the forward flow path of the control module, and assigns each of the one or more intermediate function blocks on the forward flow path of the control module to execute in the process controller if the input/output device does not support any one of the one or more intermediate function blocks, even if both the input function block and the output function block on the forward flow path of the control module are assigned to execute in the one or more field devices on the data bus.

11. The system of claim 1, wherein the routine, when executed on the processor, checks to determine whether the input/output device has sufficient capacity to execute every one of the one or more intermediate function blocks on the forward flow path of the control module, and assigns the one or more intermediate function blocks on the forward flow path of the control module to execute in the process controller if the input/output device does not have sufficient capacity to execute every one of the one or more intermediate function blocks, even if both the input function block and the output function block on the forward flow path of the control module are assigned to execute in the one or more field devices on the data bus.

12. The system of claim 1, wherein the routine, when executed on the processor, notifies a user if the routine does not assign the one or more intermediate function blocks on the forward flow path of the control module to execute in the input/output device.

13. A method of assigning function blocks of a control module to devices for execution within a process control network, the process control network having a process controller communicatively coupled to an input/output device which is connected to one or more field devices via a data bus, the method comprising:

determining a set of function blocks disposed on a forward flow path of the control module, the set of function blocks including an input function block, an output function block and one or more intermediate function blocks;

determining if each of the input function block and the output function block on the forward flow path of the control module is assigned to execute in the one or more field devices on the data bus; and

assigning at least one of the one or more intermediate function blocks on the forward flow path of the control module to execute in the input/output device if both the input function block and the output function block on the forward flow path of the control module are assigned to execute in the one or more field devices on the data bus.

14. The method of assigning function blocks of a control module of claim 13, further including assigning each of the one or more intermediate function block on the forward flow path of the control module to execute in the process controller if one or more of the input function block and the output function block on the forward flow path of the control module is not assigned to execute in the one or more field devices on the data bus.

15. The method of assigning function blocks of a control module of claim 13, wherein assigning at least one of the one or more intermediate function blocks on the forward flow path of the control module to execute in the input/output device includes assigning each of the one or more intermediate function blocks on the forward flow path of the control module to execute in the input/output device.

16. The method of assigning function blocks of a control module of claim 13, wherein communications occur over the data bus according to a pre-established communication schedule, and further including scheduling each of the input function block, the output function block and the at least one of the one or more intermediate function blocks to operate synchronously within the pre-established communication schedule.

17. The method of assigning function blocks of a control module of claim 16, wherein the pre-established communication schedule includes a repeating macrocycle, and wherein scheduling each of the input function block, the output function block and the at least one of the one or more intermediate function blocks includes creating a macrocycle in which each of the input function block, the output function block and the at least one of the one or more intermediate function blocks is scheduled to communicate over the data bus at least once during the macrocycle.

18. The method of assigning function blocks of a control module of claim 16, wherein scheduling each of the input function block, the output function block and the at least one of the one or more intermediate function blocks includes scheduling one of the input function block, the output function block and the one or more intermediate function blocks to execute at a faster rate than another one of the input function block, the output function block and the one or more intermediate function blocks.

19. The method of assigning function blocks of a control module of claim 18, further including creating a macrocycle for the pre-established communication schedule in which the one of the input function block, the output function block and the one or more intermediate function blocks is scheduled to operate more times during the macrocycle than the another one of the input function block, the output function block and the one or more intermediate function blocks.

20. The method of assigning function blocks of a control module of claim 18, further including allowing a user to specify a multiplier for one or more of the input function block, the output function block and the one or more intermediate function blocks, the multiplier indicating a relative rate of execution for an associated function block.

21. The method of assigning function blocks of a control module of claim 13, further including checking a user-settable property of the control module indicating whether the function blocks of the control module can be assigned to the input/output device and assigning the at least one of the one or more intermediate function blocks on the forward flow path of the control module to execute in the process controller if the user-settable property of the control module indicates that function blocks of the control module should be not be assigned to the input/output device, even if both the input function block and the output function block on the forward flow path of the control module are assigned to execute in the one or more field devices on the data bus.

22. The method of assigning function blocks of a control module of claim 13, further including checking a user-settable property of the input/output device indicating whether function blocks of any control module can be assigned to the input/output device, and assigning the at least one of the one or more intermediate function blocks on the forward flow path of the control module to execute in the process controller if the user-settable property of the input/output device indicates that function blocks should be not be assigned to the input/output device, even if both the input function block and the output function block on the forward flow path of the control module are assigned to execute in the one or more field devices on the data bus.

23. The method of assigning function blocks of a control module of claim 13, further including checking to determine whether the input/output device supports the at least one of the one or more intermediate function blocks on the forward flow path of the control module, and assigning the at least one of the one or more intermediate function blocks on the forward flow path of the control module to execute in the process controller if the input/output device does not support the at least one of the one or more intermediate function blocks, even if both the input function block and the output function block on the forward flow path of the control module are assigned to execute in the one or more field devices on the data bus.

24. The method of assigning function blocks of a control module of claim 13, further including checking to determine whether the input/output device has sufficient capacity to execute the at least one of the one or more intermediate function blocks on the forward flow path of the control module, and assigning the at least one of the one or more intermediate function blocks on the forward flow path of the control module to execute in the process controller if the input/output device does not have sufficient capacity to execute the at least one of the one or more intermediate function blocks, even if both the input function block and the output function block on the forward flow path of the control module are assigned to execute in the one or more field devices on the data bus.

25. A process control network, comprising:

a user interface device;

a process controller communicatively coupled to the user interface device via a first communication network;

a Fieldbus segment including a data bus and one or more Fieldbus field devices communicatively connected to the data bus, wherein the one or more Fieldbus field devices communicate over the data bus using a pre-established communication schedule;

an input/output device directly connected to the data bus and communicatively connected between the process controller and the data bus; and

a control module having plurality of communicatively linked function blocks which operate together to perform a process control loop, wherein the plurality of communicatively linked function blocks includes an input function block, an output function block and at least one intermediate function block, wherein the input function block and the output function block are located in the one or more Fieldbus field devices and the at least one intermediate function block is located in the input/output device and wherein each of the input function block, the output function block and the at least one intermediate function block communicates over the data bus using the pre-established communication schedule.

26. The process control network of claim 25, further including a processor, a computer-readable memory and a routine stored in the computer readable memory, wherein the routine executes on the processor to automatically assign the function blocks of the control module for execution in specific devices within the process control network;

wherein the routine;

determines a set of function blocks disposed on a forward flow path of the control module, the set of function blocks including the input function block, the output function block and the at least one intermediate function block;

determines if each of the input function block and the output function block on the forward flow path of the control module is assigned to execute in the one or more Fieldbus field devices on the data bus; and

assigns the at least one intermediate function block on the forward flow path of the control module to execute in the input/output device if both the input function block and the output function block on the forward flow path of the control module are assigned to execute in the one or more Fieldbus field devices on the data bus.

28. The process control network of claim 25, further including a processor, a computer-readable memory and a routine stored in the computer readable memory, wherein the routine executes on the processor to automatically schedule each of the input function block, the output function block and the at least one intermediate function block to operate synchronously within the pre-established communication schedule on the data bus.

29. The process control network of claim 28, wherein the routine, when executed on the processor, schedules one of the input function block, the output function block and the at least one intermediate function block to execute at a faster rate on the data bus than another one of the input function block, the output function block and the at least one intermediate function block.

30. The process control network of claim 25, further including a user-settable property associated with the control module indicating whether the function blocks of the control module can be assigned to the input/output device.

31. The process control network of claim 25, further including a user-settable property associated with the input/output device indicating whether function blocks of any control module can be assigned to the input/output device.

27. The process control network of 26, wherein the routine, when executed on the processor, assigns at least one intermediate function block on a forward flow path of a second control module to execute in the process controller if one or more of an input function block and an output function block on the forward flow path of the second control module is not assigned to execute in the one or more Fieldbus field devices on the data bus.