Combined Wired and Wireless Communications with Field Devices in a Process Control Environment

• US 20080274766A1
• Filed: 04/10/2008
• Published: 11/06/2008
• Est. Priority Date: 04/13/2007
• Status: Active Grant

• Current Assignee: FieldComm Group, Inc.
• Original Assignee: Hart Communication Foundation (FieldComm Group, Inc.)
• Inventors: Nixon, Mark J., Rotvold, Eric D., Pramanik, Robin S., Lennvall, Tomas P., Pratt, Wallace A.
• Granted Patent: US 8,676,219 B2
• Time in Patent Office: Days
• US Class Current: 455/552.1
• CPC Class Codes: G01D 21/00 Measuring or testing not otherwise provided for
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 56/0015 one node acting as a reference for the others
• CPC Class Codes: H04W 56/002 Mutual synchronization
• CPC Class Codes: H04W 80/00 Wireless network protocols or protocol adaptations to wireless operation

Abstract

A method of providing a wireless extension to a plant automation network connected to a plurality of wired devices, each wired device performing a process control function, includes connecting a plurality of wireless devices to the plant automation network, each of the plurality of wireless devices adapted to communicate with at least another one of the plurality of wireless devices via at least one respective wireless connection; and providing access to each of the plurality of wireless devices from a host disposed in the plant automation network, such that the host accesses the plurality of wired devices and the plurality of wireless devices using a common communication scheme.

Claims

1. A method of providing a wireless extension to a plant automation network connected to a plurality of wired devices, each wired device performing a process control function, the method comprising:

connecting a plurality of wireless devices to the plant automation network, each of the plurality of wireless devices adapted to communicate with at least another one of the plurality of wireless devices via at least one respective wireless connection; and

providing access to each of the plurality of wireless devices from a host disposed in the plant automation network, wherein the host accesses the plurality of wired devices and the plurality of wireless devices using a common communication scheme.

2. The method of claim 1, wherein providing access to each of the plurality of wireless devices includes:

assigning a substantially unique address compatible with a network addressing scheme to each of the plurality of wireless devices;

wherein each of the plurality of wired devices has a substantially unique address compatible with the network addressing scheme.

3. The method of claim 2, wherein the network addressing scheme is consistent with the Highway Addressable Remote Transducer (HARTS protocol.

4. The method of claim 1, wherein each of the plurality of wired devices communicates using a wired communication protocol;

wherein each of the plurality of wireless devices communicates using a wireless communication protocol; and

wherein providing access to each of the plurality of wireless devices from a host disposed in the plant automation network includes;

receiving a command from the host compatible with the wired communication protocol;

determining whether the command is associated with one of the plurality of wired devices or one of the plurality of wireless devices; and

translating the command to the wireless communication protocol if the command is associated with one of the plurality of wireless devices.

5. The method of claim 1, wherein providing access to each of the plurality of wireless devices includes providing a gateway device connected to at least one of the plurality of wireless devices via a wireless connection and to the automation network via a wired connection.

6. The method of claim 5, wherein connecting a plurality of wireless devices to the plant automation network includes generating a mesh multi-node network including each of the plurality of wireless devices as a respective node and the gateway device as another node.

7. The method of claim 5, wherein providing a gateway device includes translating between a first protocol and a second protocol at the gateway device;

wherein the first protocol supports wired communications in the plant automation network and the wherein the second protocol supports wireless communications between the gateway device and each of the plurality of wireless devices.

8. The method of claim 5, further comprising providing wireless access to each of the plurality of wireless devices from a handheld device bypassing the gateway device when the handheld device is physically proximate to at least one of the plurality of wireless devices.

9. The method of claim 8, wherein providing wireless access to each of the plurality of wireless devices from the handheld device includes:

activating a scheduling resource reserved for the handheld device; and

allowing the handheld device to directly communicate with at most one of the wireless devices and only within a time period associated with the scheduling resource reserved for the handheld device.

10. The method of claim 5, further comprising:

caching at least one of process data, alarm data, or device data as a cache data related to one of the plurality of wireless devices at the gateway device; and

wherein

providing access to each of the plurality of wireless devices from a host disposed in the plant automation network includes;

receiving a change notification request from the host specifying a subset of the plurality of wired devices; and

reporting the cached data to the host if the one of the plurality of wireless devices is associated with the subset.

11. The method of claim 10, wherein caching process data includes receiving an unsolicited burst mode data report from the one of the plurality of wireless devices at the gateway device.

12. The method of claim 10, wherein caching alarm data includes:

receiving, at the gateway device, an alarm from the one of the plurality of wireless devices;

generating an acknowledgement corresponding to the alarm;

generating a timestamp associated with a time of arrival of the alarm; and

caching the alarm in a memory of the gateway device for reporting to a requesting entity associated with the host.

13. The method of claim 10, wherein at least one of reporting the cached data and receiving a change notification request is associated with a real-time delivery mode and the other one of reporting the cached data and receiving a change notification request is associated with a non-real-time delivery mode.

14. The method of claim 1, wherein each of the plurality of wired devices communicates using a wired communication protocol having at least a first physical layer and an application layer layered over the first physical layer and zero or more intermediate layers;

and wherein each of the plurality of wireless devices communicates using a wireless communication protocol having at least a second physical layer and the application layer layered over the second physical layer and zero or more intermediate layers.

15. The method of claim 14, wherein the application layer is consistent with the HART®

communication protocol.

16. The method of claim 1, wherein connecting a plurality of wireless devices to the plant automation network includes generating a mesh multi-node network wherein each of the plurality of wireless devices is a respective node of the mesh multi-node network;

the method further comprising;

operatively coupling at least one adapter device to one of the plurality of wired devices to enable the one of the plurality of wired devices to operate in the mesh multi-node network as another node of the mesh multi-node network.

17. The method of claim 1, wherein connecting a plurality of wireless devices to the plant automation network includes generating a mesh multi-node network including each of the plurality of wireless devices as a respective node;

the method further comprising;

accepting a request from a new wireless device not included in the plurality of wireless device to join the mesh multi-node network; and

allowing the host to access the new wireless device without restarting the mesh multi-node network.

18. A method of forming a combined wired and wireless network operating in a process control environment by extending a wired network having a plurality of wired field devices, the method comprising:

connecting a wireless gateway to the wired network via a first wired connection;

adding a first wireless device to the combined wired and wireless network, including;

wirelessly connecting the first wireless device to a wireless gateway; and

forming an independently operable wireless network having the first wireless device and the wireless gateway;

adding a first one of the plurality of wired field devices to the wireless network, including;

connecting the first one of the plurality of wired field devices to a wireless adapter via a second wired connection; and

connecting the wireless adapter to the wireless network via a wireless connection.

19. The method of claim 18, wherein adding a first one of the plurality of wired field devices to the wireless network includes leaving an original wired connection of one of the plurality of wired field devices intact.

20. The method of claim 18, wherein connecting a wireless gateway to the wired network via a first wired connection includes connecting the wireless gateway to a Distributed Control System (DCS).

21. The method of claim 18, further comprising adding a second one of the plurality of wired field devices to the wireless network, including connecting the second one of the plurality of field devices to the wireless adapter.

22. The method of claim 21, wherein the connecting the second one of the plurality of field devices to the wireless adapter includes associating the wireless adapter with a single address in the wireless network;

and wherein adding the first one of the plurality of wired field devices and the second one of the plurality of wired field devices to the wireless network includes tunneling data between the wired network and each of the first one of the plurality of wired field devices and the second one of the plurality of wired field devices via the wireless gateway.

23. A method of forming a combined wired and wireless network operating in a process control environment by extending a wired network having a plurality of wired field devices, the method comprising:

connecting a plurality of wireless network access points to the wired network via a respective wired connection;

adding a plurality of wireless devices to the combined wired and wireless network, including;

wirelessly connecting each of the plurality of wireless devices to at least one of the wireless plurality of wireless network access points;

forming an independently operable wireless network including the plurality of wireless devices and the plurality of wireless network access points; and

connecting each of the plurality of wireless network access points to a virtual gateway operating outside the wireless network and outside the wired network;

wherein the virtual gateway is a software module running on a processor.

24. The method of claim 23, wherein wirelessly connecting each of the plurality of wireless devices to at least one of the wireless plurality of wireless network access points includes automatically reconnecting each of the plurality of wireless devices previously connected to a first one of the plurality of wireless network access points to a second one of the plurality of wireless network access points in response to detecting a failure of the first one of the plurality of wireless network access points.

25. The method of claim 23, further comprising:

adding a first one of the plurality of wired field devices to the wireless network, including;

connecting the first one of the plurality of wired field devices to a wireless adapter via a second wired connection; and

connecting the wireless adapter to the wireless network via a wireless connection.