System and method for implementing safety instrumented systems in a fieldbus architecture

• US 7,167,762 B2
• Filed: 09/30/2005
• Issued: 01/23/2007
• Est. Priority Date: 08/21/1997
• Status: Expired due to Fees

• Current Assignee: FieldComm Group, Inc.
• Original Assignee: Fieldbus Foundation (FieldComm Group, Inc.)
• Inventors: Ramachandran, Ram, Gabler, John Carl, Duffy, Joseph D., Glanzer, David A., Mitschke, Stephen B., Berge, L Jonas F.
• Primary Examiner(s): PATEL, RAMESH B
• Application Number:
  US11/240,939
• Publication Number:
  US 20060025872A1
• Time in Patent Office: 480 Days
• Field of Search: 700 2- 4, 700/7, 700 12- 19, 700 24- 37, 700/79, 700 83- 87, 702/122, 702/182, 702/186, 709223-227, 709/217, 709/245, 709/250, 709/201, 719/328, 719/329, 719/332, 710/21, 710 67- 72, 710/75, 710/105, 710/109, 713/170, 713/172, 713/176
• US Class Current: 700/79
• CPC Class Codes: G05B 11/01 electric
• CPC Class Codes: G05B 15/02 electric
• CPC Class Codes: G05B 19/042 using digital processors G05B19/05 takes precedence
• CPC Class Codes: G05B 2219/13127 Hybrid sfc for description of sequence, ladder diagram for conditions, interlock
• CPC Class Codes: G05B 2219/15068 SBC single board computer, UCM universal control module
• CPC Class Codes: G05B 2219/23256 Hybrid programming, part sequence, part continuous
• CPC Class Codes: G05B 2219/25085 Several function expansion units for master, main unit, universal system
• CPC Class Codes: G05B 2219/25428 Field device
• CPC Class Codes: G05B 2219/31118 Universal interface between asi and fieldbus, for any fielddevice
• CPC Class Codes: G05B 9/02 electric
• CPC Class Codes: H04L 67/125 involving control of end-device applications over a network
• CPC Class Codes: H04L 67/62 Establishing a time schedule for servicing the requests
• CPC Class Codes: H04L 69/08 Protocols for interworking; Protocol conversion

Abstract

An apparatus, system and process is provided for communicating safety-related data, over an open system, from a sender to a receiver. Safety-related components, including function blocks, flexible function blocks, resource blocks and transducer blocks, as well as, safety-related objects are provided. Also, an extended safety-related protocol provides for authenticating communications between safety-related components over an existing black channel, such as one using a fieldbus Architecture.

Claims

1. An apparatus for operating in a block-oriented safety related open control system comprising:

a memory, which includes at least one safety related component;

a processor, operably connected to the memory, wherein the processor executes the safety related component based on a system schedule;

a medium attachment unit, which translates input messages and output messages between the processor and a transmission medium using an extended safety-related protocol; and

wherein the processor manages the system schedule, instructs a second apparatus when it can execute a second safety related component, and passes a token to the second apparatus when a time arises for executing the second safety related component.

2. The apparatus of claim 1, wherein the apparatus is operably connected to a high speed Ethernet bus.

3. The apparatus of claim 1, wherein the memory includes at least one non-safety related component.

4. A process for communicating safety related data obtained by a first device to a second device comprising:

obtaining, using a first device, information useful ingenerating a first data sequence;

generating the first data sequence using the obtained information;

generating a first authenticator for the first data sequence;

combining the first data sequence and the first authenticator; and

communicating the combination to the second device.

5. The process of claim 4, wherein the first device is a publisher and the second device is a subscriber in a publisher-subscriber communications architecture.

6. The process of claim 4, wherein the first device is a client and the second device is a server in a client-server communications architecture.

7. A process for authenticating a received message, wherein the received message includes information pertaining to a safety related component, comprising:

receiving a first data sequence;

receiving a first authenticator related to the first data sequence;

generating a second data sequence based upon the first data sequence;

calculating a second authenticator based upon the second data sequence;

comparing the first authenticator and the second authenticator;

when the first authenticator and the second authenticator are not the same, rejecting the received message; and

when the first authenticator and the second authenticator are the same,

receiving a sequence number related to the first data sequence;

obtaining an expected sequence number; and

comparing the received sequence number to the expected sequence number;

when the received sequence number and the expected sequence number are not the same, rejecting the message; and

when the received sequence number and the expected sequence number are the same, accepting the message.

8. The process of claim 7, wherein the process is used to authenticate a message communicated to a safety related component in a block-oriented safety related open control system.

9. The process of claim 7, wherein the process is executed by a client in a client-server architecture.

10. The process of claim 9, wherein the process comprises communicating a request to read a parameter related to a safety related component to a server and the first data sequence contains a response, communicated by the server, to the request.

11. The process of claim 7, wherein the process is executed by a subscriber in a publisher-subscriber architecture.

12. The process of claim 7, wherein the first data sequence includes data relating to a safety related component used by a device in an open control system.

13. The process of claim 12, wherein the open control system utilizes a fieidbus architecture.

14. The process of claim 12, wherein the first data sequence further includes at least one of a sequence number, an object index and a connection key.

15. The process of claim 12, wherein the first data sequence further includes at least one of a sequence number, an object index and a connection key.

16. The process of claim 7, wherein the first data sequence includes the first authenticator.

17. The process of claim 7, wherein the first data sequence includes the sequence number.

18. The process of claim 7, wherein the first data sequence includes at least one of an object index and a connection key.

19. The process of claim 7, wherein the second data sequence comprises an expected connection key, a received sequence number, and an expected object index, wherein the received sequence number is received in the first data sequence.

20. The process of claim 14, wherein the first data sequence comprises a sub-index.