Distributed object-oriented building automation system with reliable asynchronous communication

• US 6,167,316 A
• Filed: 04/03/1998
• Issued: 12/26/2000
• Est. Priority Date: 04/03/1998
• Status: Expired due to Term

• Current Assignee: Johnson Controls Technology Company (Johnson Controls International plc)
• Original Assignee: Johnson Controls Technology Company (Johnson Controls International plc)
• Inventors: Rasmussen, David E., Gottschalk, Donald A., Gloudeman, Jeffrey J., Wagner, Michael E.
• Primary Examiner(s): Grant, William
• Assistant Examiner(s): RODRIGUEZ, PAUL L
• Application Number:
  US09/054,647
• Time in Patent Office: 998 Days
• Field of Search: 700/275, 700/276, 700/277, 700/299, 700/2, 700/79, 707/103, 709/223
• US Class Current: 700/2
• CPC Class Codes: G05B 2219/2642 Domotique, domestic, home control, automation, smart house
• CPC Class Codes: G05B 2219/36035 Special language, task programming, oop object oriented programming
• CPC Class Codes: G06F 9/465 Distributed object oriented systems remote method invocation [RMI] G06F9/548

Abstract

A computer-implemented building automation system is provided with an asynchronous communication architecture for supporting object-oriented applications that interact with distributed building automation devices. Standard application objects which need to be informed of changes to the value of another object'"'"'s attributes use a connection object to establish an asynchronous link between standard objects. A source object has a control attribute that changes based upon the execution of this object'"'"'s control method which in turn is linked to a second control attribute of a destination object. By linking these attributes, a connection object is defined to manage information being passed between these two objects. Upon instantiation of the connection object, it registers the second control attribute with the source object to receive "significant" changes in the value of its control attribute. A "significant" change is defined by a change sensitivity property associated with the control attribute, such that a message containing the value of the control attribute is transmitted to the connection object when the change in the value of the control attribute exceeds the value of the change sensitivity property. The connection object in turn writes the attribute'"'"'s value from the source object to the second control attribute of the destination object. Thus, execution of the connection object happens independently from the destination object. This communication architecture also implements a reliability data structure to improve asychronous communication when the building automation system is distributed across various building automation devices.

Claims

1. A computer-implemented building automation system for supporting interaction with building automation devices, comprising:

a common object superclass stored in a computer readable memory that defines a plurality of common objects through instantiation such that said common objects have attributes for storing data and have methods for processing stored data;

a source common object for performing a first control method, having a first control attribute that may change based on said first control method and a reporting method for transmitting a message containing the value of said first control attribute in response to a change in the value of said first control attribute;

a destination common object for performing a second control method, having a second control attribute for use by said second control method whose value is connected to said first control attribute; and

a connection common object for establishing a connection between said source object and said destination object, having a linking method for registering said second control attribute of said destination object with said source object, and a writing method for providing the value of said first control attribute to said second control attribute of said destination object in response to receiving said message from said source object, wherein said connection object comprises a mapping data structure for storing a source object identifier, a source attribute identifier, a destination object identifier, a destination attribute identifier and an attribute value.

2. The computer-implemented building automation system of claim 1 whereby said connection object executing said writing method is independent from said destination object executing said second control method.

3. The computer-implemented building automation system of claim 1 wherein said first control attribute is further defined as having a change sensitivity property, whereby said reporting method executes when said change in the value of said first control attribute exceeds said change sensitivity property.

4. The computer-implemented building automation system of claim 1 wherein said first control attribute is further defined as having a display precision property, whereby a computer-human interface displays said first control attribute based on said display precision property.

5. The computer-implemented building automation system of claim 1 wherein said source object further comprises a reliability attribute indicative of the dependability of said source object, whereby said reliability attribute being used to prevent propagation of unreliable attribute values in the building automation system.

6. The computer-implemented building automation system of claim 5 wherein said writing method detects an unreliable state for said source object using said reliability attribute, thereby preventing transmission of unreliable attribute values to said destination object.

7. The computer-implemented building automation system of claim 5 wherein said reporting method detects an unreliable state for said source object using said reliability attribute and transmits said message containing a default value for said first control attribute.

8. The computer-implemented building automation system of claim 5 wherein said reporting method detects an unreliable state for said source object using said reliability attribute, and transmits said message containing a last reliable value for said first control attribute.

9. The computer-implemented building automation system of claim 5 wherein said reporting method detects an unreliable state for said source object using said reliability attribute, computes a reliable value for said first control attribute, and transmits said message containing said computed reliable value.

10. The computer-implemented building automation system of claim 5 wherein said message includes the value of said reliability attribute and said writing method providing the value of said reliability attribute to said destination object, whereby said second control method detects an unreliable state for said source object using the value of said reliability attribute and uses a default value of said first control attribute.

11. The computer-implemented building automation system of claim 5 wherein said message includes the value of said reliability attribute and said writing method providing the value of said reliability attribute to said destination object, whereby said second control method detects an unreliable state for said source object using the value of said reliability attribute and uses a last reliable value of said first control attribute.

12. The computer-implemented building automation system of claim 5 wherein said message includes the value of said reliability attribute and said writing method providing the value of said reliability attribute to said destination object, whereby said second control method detects an unreliable state for said source object using the value of said reliability attribute, computes a reliable value of said first control attribute, and uses said computed reliable value.

13. The computer-implemented building automation system of claim 5 further comprises a computer-human interface for displaying said reliability attribute of said source object.

14. The computer-implemented building automation system of claim 5 wherein said first control attribute is further defined as having a reliability property indicative of the reliability of said first control attribute when said reliability attribute indicates an unreliable state for said source object.

15. The computer-implemented building automation system of claim 14 wherein said reporting method transmits a message containing the value of said first control attribute when said reliability property indicates a reliable state for said first control attribute and said reliability attribute indicates an unreliable state for said source object.

16. The computer-implemented building automation system of claim 14 wherein said message includes the value of said reliability property and said writing method provides the value of said reliability property to said destination object, when said reliability property indicates an unreliable state for said first control attribute and said reliability attribute indicates an unreliable state for said source object, whereby said second control method detects an unreliable state of said first control attribute using the value of said reliability property and uses a default value of said first control attribute.

17. The computer-implemented building automation system of claim 14 wherein said message includes the value of said reliability property and said writing method provides the value of said reliability property to said destination object, when said reliability property indicates an unreliable state for said first control attribute and said reliability attribute indicates an unreliable state for said source object, whereby said second control method detects an unreliable state for said first control attribute using the value of said reliability property and uses a last reliable value of said first control attribute.

18. The computer-implemented building automation system of claim 14 wherein said message includes the value of said reliability property and said writing method provides the value of said reliability property to said destination object, when said reliability property indicates an unreliable state for said first control attribute and said reliability attribute indicates an unreliable state for said source object, whereby said second control method detects an unreliable state for said first control attribute using the value of said reliability property, computes a reliable value of said first control attribute, and uses said computed reliable value.

19. An asynchronous communication method for supporting applications in a computer-implemented building automation system, comprising:

defining a plurality of common objects in a computer readable memory through instantiation such that said common objects have attributes for storing data and have methods for processing stored data;

defining a communication connection between a first control attribute of a source common object and a second control attribute of a destination common object;

performing a first control method of said source object, such that a first control attribute being changed based on said first control method;

registering said second control attribute with said source object upon instantiation of a connection common object, such that a communication connection being established between said source object and said destination object, wherein said connection object comprises a mapping data structure for storing a source object identifier, a destination object identifier, an attribute identifier, and an attribute value;

transmitting a message containing the value of said first control attribute from said source object to said connection object, wherein the transmission of said message is based on a change in the value of said first control attribute; and

writing the value of said first control attribute to said second control attribute of said destination object by said connection object in response to said message, whereby said destination object performs a second control method using said second control attribute.

20. The asynchronous communication method of claim 19 further comprising a detector for monitoring changes in the value of said first control attribute, wherein said first control attribute is further defined as having a change sensitivity property such that transmitting said message occurs when the change in the value of said first control attribute exceeds said change sensitivity property.

21. The asynchronous communication method of claim 19 wherein said source object further comprises a reliability attribute indicative of the dependability of said source object, whereby said reliability attribute being used to prevent propagation of unreliable attribute values in the building automation system.

22. The asynchronous communication method of claim 21 wherein said connection object detects an unreliable state for said source object using said reliability attribute, thereby preventing transmission of unreliable value for said first control attribute to said destination object.

23. The asynchronous communication method of claim 21 wherein said message includes the value of said reliability attribute and said connection object providing the value of said reliability attribute to said destination object, whereby said second control method detects an unreliable state for said source object using the value of said reliability attribute and uses a default value for said first control attribute.

24. The asynchronous communication method of claim 21 wherein said message includes the value of said reliability attribute and said connection object providing the value of said reliability attribute to said destination object, whereby said second control method detects an unreliable state for said source object using the value of said reliability attribute and uses a last reliable value of said first control attribute.

25. The asynchronous communication method of claim 21 wherein said message includes the value of said reliability attribute and said connection object providing the value of said reliability attribute to said destination object, whereby said second control method detects an unreliable state for said source object using the value of said reliability attribute, computes a reliable value of said first control attribute, and uses said computed reliable value.

26. The asynchronous communication method of claim 21 wherein said first control attribute is further defined as having a reliability property indicative of the reliability of said first control attribute when said reliability attribute indicates an unreliable state for said source object.

27. The asynchronous communication method of claim 21 wherein said message containing the value of said first control attribute is transmitted when said reliability property indicates a reliable state for said first control attribute and said reliability attribute indicates an unreliable state for said source object.

28. A computer-implemented building automation system for supporting interaction with building automation devices, comprising:

a common object superclass stored in a computer readable memory that defines a plurality of common objects through instantiation such that said common objects have attributes for storing data and have methods for processing stored data;

a source common object for performing a first control method, having a first control attribute, a reliability attribute indicative of the dependability of said source object, a reporting method for transmitting a message containing the value of said first control attribute and said reliability attribute; and

a destination common object for performing a second control method, having a second control attribute and a writing method for receiving said message and updating said second control attribute with the value of said first control attribute, whereby said reliability attribute being used by said destination object to prevent propagation of unreliable attribute values in the building automation system.