# Patent

## Title
Handheld field maintenance tool with improved functionality

## Abstract

A handheld field maintenance tool with improved functionality is provided. The handheld field maintenance tool includes a keypad, a display, a short-range wireless transceiver and a processor. The processor is coupled to the keypad, the display and the short-range wireless transceiver. The processor is also coupled to memory having a plurality of instructions stored therein, which instructions, when executed by the processor, cause the processor to perform at least one of remote wireless display; remote wireless keypress injection; and wireless printing.

## Background
CROSS-REFERENCE TO RELATED APPLICATION
The present application is based on and claims the benefit of U.S. provisional patent application Ser. No. 61/178,751 filed May 15, 2009, the content of which is hereby incorporated by reference in its entirety.


BACKGROUND
Handheld field maintenance tools are known. Such tools are highly useful in the process control and measurement industry to allow operators to conveniently communicate with and/or interrogate field devices in a given process installation. Examples of such process installations include petroleum, pharmaceutical, chemical, pulp, and other fluid processing installations. In such installations, the process control and measurement network may include tens or even hundreds of various field devices which periodically require maintenance to ensure that such devices are functioning properly and/or calibrated. Moreover, when one or more errors in the process control and measurement installation are detected, the use of a handheld field maintenance tool allows a technician to quickly diagnose such errors in the field. Handheld field maintenance tools are generally used to configure, calibrate, and diagnose problems relative to intelligent field devices using digital process communication protocols.
Since at least some process installations may involve highly volatile, or even explosive, environments, it is often beneficial, or even required, for field devices and the handheld field maintenance tools used with such field devices to comply with intrinsic safety requirements. These requirements help ensure that compliant electrical devices will not generate a source of ignition even under fault conditions. One example of Intrinsic Safety requirements is set forth in: APPROVAL STANDARD INTRINSICALLY SAFE APPARATUS AND ASSOCIATED APPARATUS FOR USE IN CLASS I, II and III, DIVISION NUMBER 1 HAZARDOUS (CLASSIFIED) LOCATIONS, CLASS NUMBER 3610, promulgated by Factory Mutual Research October, 1998. An example of a handheld field maintenance tool that complies with intrinsic safety requirements includes that sold under trade designation Model 475 Field Communicator, available from Emerson Process Management of Austin, Tex.
Given the unique environmental considerations for field devices, communication signaling has traditionally been carefully controlled. Examples of industrial process communication protocols include the Highway Addressable Remote Transducer (HART®) Protocol, and the FOUNDATIONTM Fieldbus Protocol. Both of these protocols are considered wired protocols in that a physical wire connection is made to each field device.
SUMMARY
A handheld field maintenance tool with improved functionality is provided. The handheld field maintenance tool includes a keypad, a display, a short-range wireless transceiver and a processor. The processor is coupled to the keypad, the display and the short-range wireless transceiver. The processor is also coupled to memory having a plurality of instructions stored therein, which instructions, when executed by the processor, cause the processor to perform at least one of remote wireless display; remote wireless keypress injection; and wireless printing.



BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A and 1B are diagrammatic views of a handheld field maintenance tool coupled to a field device in accordance with the prior art.
FIG. 2 is a diagrammatic view of a handheld field maintenance tool with which embodiments of the present invention are particularly useful.
FIG. 3 is a system block diagram of a handheld field maintenance tool with which embodiments of the present invention are particularly useful.
FIG. 4 is a flow diagram of a method of printing field device configuration data from a handheld field maintenance tool directly to a printer in accordance with an embodiment of the present invention.
FIG. 5 is a diagrammatic view of a system for remotely displaying information from a handheld field maintenance tool using wireless communication in accordance with an embodiment of the present invention.



DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS
FIGS. 1A and 1B are diagrammatic views of a handheld field maintenance tool 22 coupled to field devices in accordance with the prior art. As shown in FIG. 1A, handheld field maintenance tool 22 includes a pair of terminals 25, 27 that couple to test leads 30, 32, respectively, which are then coupled to terminals 24 of field device 20. Terminals 24 may be dedicated terminals to allow such a handheld field maintenance tool to couple to device 20 and interact with device 20.
FIG. 1B shows an alternate arrangement where handheld field maintenance tool 22 couples directly to the process control loop 34 to which field device 23 is coupled. In either case, the wired connection between the handheld field maintenance tool and the field device allows the handheld field maintenance tool to interact with the desired field device 20, 23.
FIG. 2 is a diagrammatic view of a handheld field maintenance tool interacting with a field device in accordance with an embodiment of the present invention. System 100 includes handheld field maintenance tool 102 communicating with field device 104.
Handheld field maintenance tool 102 is communicatively coupled to field device 104 via communication link 114. Communication link 114 can take any suitable form including wired connections as shown in FIGS. 1A and 1B, as well as wireless communication techniques that are currently being used or being developed. Handheld field maintenance tool 102 allows a technician to interact with field device 104 to configure, calibrate, and/or diagnose problems with respect to field device 104 using a digital process communication protocol such as FOUNDATIONTM Fieldbus and/or the HART® protocol. Handheld field maintenance tools, such as tool 102 can be used to save configuration data from field devices, such as field device 104. Field device 104 may be any device that senses a variable in the process and transmits information related to the variable over a process communication loop; such as a pressure or temperature transmitter. Field device 104 may also be a device that receives information from a process communication loop and sets a physical parameter, such as a valve closure, based on the information. Field device 104 is depicted as an industrial process fluid pressure transmitter having a pressure manifold 106 coupled thereto, and an electronics enclosure 108. Field device 104 is provided for illustrative purposes only. In reality, field device 104 may be any industrial device, such as a process fluid temperature transmitter, process fluid level transmitter, process fluid flow transmitter, valve controller, or any other device that is useful in the measurement and/or control of industrial processes.
For the various field devices, configuration data can be transferred to a suitable device that may employ application software to organize, format, and/or print such configuration data in an easily readable form.
Handheld field maintenance tool 102 generally includes a user interface that comprises a display 120 as well as a number of user input buttons 122. Display 120 may be any suitable display such as an active-matrix liquid crystal display, or any other suitable display that is able to provide useful information. Buttons 122 may comprise any suitable arrangement of buttons relative to any number of functions to which the handheld field maintenance tool may be directed. Buttons 122 may comprise a numeric keypad, an alphanumeric keypad, any suitable number of custom functions and/or navigation buttons, or any combination thereof. Due to handheld field maintenance tool 102 being sized to be carried by a technician for extended periods of time and to be held in the hand during use, display 120 and keys 122 are generally relatively small. This is typically not a problem when handheld field maintenance tool 102 is held in the hand, but it does create difficulties if the technician is trying to illustrate use of the handheld field maintenance tool to others that must view display 120 and keys 122 from a relative distance.
Embodiments of the present invention generally provide improved functionality for a handheld field maintenance tool by taking advantage of a relatively short-range wireless communication transceiver utilized by the handheld field maintenance tool. One example of such a relatively short-range radio frequency transceiver is that in accordance with a known Bluetooth specification, such as Bluetooth Specification 2.1 rated at Power Class 2.
FIG. 3 is a block diagram of handheld field maintenance tool 102 with which embodiments of the present invention are particularly applicable. Tool 102 includes a field device interface 150 operably coupled to controller 152 which is preferably a microprocessor. Field device interface 150 can take any suitable form. For example, in embodiments where the handheld field maintenance tool couples to field devices via a wired connection, field device interface 150 may include one or more wired process communication modules. Examples include a process communication module that allows communication in accordance with the HART® protocol, or a process communication module that allows communication in accordance with the FOUNDATIONTM Fieldbus protocol. In other embodiments, field device interface 150 may include wireless process communication circuitry, such as the more recently-developed WirelessHART communication. Additionally, new wired or wireless process communication techniques and protocols can be used in accordance with embodiments of the present invention.
Controller 152 preferably includes, or is coupled to, memory 154 that stores data used by and/or acquired by handheld field maintenance tool 102 during operation. Additionally, memory 154 preferably includes software instructions that, when executed by processor 152, cause processor 152 to execute a number of improved functions. Examples of these improved functions will be provided in greater detail later in the specification.
Handheld field maintenance tool 102 includes user interface 156 operably coupled to controller 152. User interface 156 may include an output 158 in the form of a display and an input 160 in the form of one or more keys or buttons. While embodiments of the present invention are generally described with respect to the user input being the form of keys or buttons, any suitable input can be received from the user or technician. Other examples include dials, knobs, thumbwheels, switches, audio input, cursor control input, et cetera.
Handheld field maintenance tool 102 also includes short-range wireless transceiver 162 coupled to controller 152. In a preferred embodiment, transceiver 162 is a Bluetooth communication module that allows communication in accordance with a known Bluetooth specification, such as Bluetooth Specification 2.1 rated at Power Class 2. However, alternate protocols, such as Wi-Fi wireless networking technologies (IEEE 802.11(b), IEEE 802.11(g) wireless networking devices built by Linksys of Irvine, Calif.).
As set forth above, one of the functions of handheld field maintenance tools is the configuration and commissioning of field devices, such as process fluid pressure or temperature measuring devices. These handheld field maintenance tools can be used to save configuration data from such field devices. The configuration data is acquired by the handheld field maintenance tool 102 via its field device interface module 150. This information is preferably stored in memory within handheld field maintenance tool 102, such as memory 154. Memory 154 can be volatile memory, such as RAM, non-volatile memory, such as ROM, or flash memory or any combination thereof. Typically, in order to print or otherwise use the configuration information, the handheld field maintenance tool must be coupled to a computer via a suitable interface, such as a serial connection, or infrared communication connection to upload the configuration information to the computer. Thereafter, the information is formatted as desired by the computer and printed, stored, or otherwise employed.
In accordance with an embodiment of the present invention, the short-range wireless communication module is employed in conjunction with instructions executed by processor 152 to allow the handheld field maintenance tool to automatically discover and/or pair with a wirelessly-communicating printing device, such as a Bluetooth-enabled printer. Once a device is discovered and available, controller 152 is able to format configuration data for direct printing by the printer. Accordingly, no computer or other such computing device is required in that the configuration information can be printed directly from the wirelessly-communicating printer based upon wireless information transmitted from the handheld field maintenance tool directly to the printer. This is important because a computer is not generally considered very portable and even laptop computers are generally not considered safe enough to be carried into potentially explosive environments. Accordingly, such computers have generally been prohibited from highly explosive or flammable environments. In contrast, the provision of a low-power intrinsically safe printer could be carried with the technician into such environments. Further still, even if such printers were not intrinsically safe, the wireless communication could span a physical barrier where the tool itself is in an explosive environment, but the printing occurs in a safe environment.
FIG. 4 is a flow diagram of a method of printing configuration data from a handheld field maintenance tool in accordance with an embodiment of the present invention. Method 200 begins at block 202 where a handheld field maintenance tool, such as tool 102, discovers the communicative proximity of a short-range wireless-compatible printer. Communicative proximity is intended to mean that the handheld field maintenance tool is within the wireless transmission range of both the short-range wireless transceiver 162 and the transceiver of the printing device. Once the device is discovered, method 200 continues at block 204 where the handheld field maintenance tool pairs, couples, or otherwise establishes suitable handshakes to generate a session or job with the printing device. At block 206, the configuration information stored within memory, such as memory 154, is formatted based upon the printer. For example, if the printer reveals that it has a print width of 40 characters, the formatting at block 206 can be adjusted accordingly. Next, at block 208, the formatted configuration information is transmitted wirelessly, via a short-range wireless transceiver such as transceiver 162, to the printer. Then, at block 210, the printer prints the received formatted configuration information
Another important function provided by embodiments of the present invention is the facilitation of training, or otherwise showing others, the interactions that a technician or user is generating with the handheld field maintenance tool. Typically, handheld field maintenance tools have a relatively small screen and small numeric or alphanumeric keypad. Since the screens on handheld field maintenance tools are small, it is difficult to view them from a distance. This becomes a problem in a training situation where the user might want to view the handheld field maintenance tool screen on a personal computer and, in turn, project it on a screen. It is possible to connect handheld field maintenance tools to personal computers using hard-wired cables employing, for example, the Ethernet protocol so that the display can be communicated from the handheld field maintenance tool to the personal computer. However, there are some drawbacks to this approach. First, the handheld field maintenance tool must have an Ethernet interface (such as an RJ-45 socket) on the handheld field maintenance tool itself in order to accept the cable. The presence of such a connector would make it difficult, if not impossible, to comply with intrinsic safety requirements for a handheld field maintenance tool. Additionally, the wired interface can make it difficult to move the handheld field maintenance tool around or to locate it a distance from the personal computer. Finally, the wired interface requires the personal computer to also have an Ethernet connector that is available to plug in the cable from the handheld field maintenance tool. While virtually all personal computers generally have an Ethernet connector, the connector is generally consumed by an Ethernet connection to the network so that the computer can interact with other servers or devices. It is somewhat rare for a computer to have an unused Ethernet connector.
In accordance with another embodiment of the present invention, a controller, such as controller 152 of a handheld field maintenance tool, uses a relatively short-range wireless transceiver, such as transceiver 162, to communicate graphical information displayed on a display of the handheld field maintenance tool to a third device, such as a personal computer, for display on the personal computer. Additionally, the transceiver can also be used to show key presses and keystrokes or other forms of user input received by the handheld field maintenance tool on the personal computer or external display device. The system can also work in the reverse in that, when suitably configured, the handheld field maintenance tool can receive keystrokes from the personal computer and/or display information from the personal computer. This may be particularly useful in situations where the handheld field maintenance tool is coupled directly to a field device located in an inconvenient location where the requisite position of the handheld field maintenance tool is not conducive to user input. In such an instance, the technician could return to a computer, potentially disposed at a safe and/or convenient location, and interact with the handheld field maintenance tool using the short-range wireless transceiver.
FIG. 5 is a diagrammatic view of a system for mirroring interaction on a handheld field maintenance tool via wireless communication in accordance with an embodiment of the present invention. System 300 includes operating system software 302 being executed by controller 152 in a handheld field maintenance tool, such as tool 102. Operating system 302 includes an input/output module 304 that facilitates interaction with physical devices, such as output display 120, keys 122, and short-range wireless transceiver 162 (shown in FIG. 3). Application software 306 runs on top of operating system 302 and provides an improved mirroring function for the handheld field maintenance tool in an embodiment of the present invention.
In accordance with an embodiment of the present invention shown in FIG. 5, keystrokes and/or display outputs from keys 122, and display 120, respectively, can be mirrored to computing device 310 via wireless communication 312. Wireless communication is particularly advantageous in that the handheld field maintenance tool may be disposed in a potentially hazardous or inconvenient location or in a location that is simply not very accessible to a technician. However, computing device 310 is located in a safe, convenient location and generally has a screen or other suitable display 314 that can be viewed by a number of people. In some situations where a large number of people must view the screen, an optional external screen such as an overhead projector 316 can be coupled to computer 310, either directly or indirectly, and can display the output from the handheld field maintenance tool in substantially real-time. Additionally, individual key presses can be viewed or otherwise displayed on screens 314 and/or 316 in any suitable manner. While communication from the handheld field maintenance tool to computing device 310 facilitates training or other interactions where a relatively large number of people who may wish to view the interaction, communication from the computing device 310 to the handheld field maintenance tool is also useful. Particularly, communication from computing device 310 to the handheld field maintenance tool is useful in situations where the handheld field maintenance tool is physically coupled to a field device in a position that is relatively inaccessible. Thus, instead of the technician coupling the handheld field maintenance tool to a field device and interacting with the device while precariously balanced on a ladder, for example, the technician can simply return to computing device 310 and perform interactions with the field device via the handheld field maintenance tool in the safe location of computing device 310 with relative ease.
Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.

## Claims

1. A method of interacting with a field device located in a relatively inaccessible location using an intrinsically-safe handheld field maintenance tool, the method comprising:
physically coupling the intrinsically-safe handheld field maintenance tool to the field device via a field device interface that comprises a plurality of wired process communication modules;
providing an operating system having an I/O module, wherein the intrinsically-safe handheld field maintenance tool has a local display that is driven, at least in part, by the I/O module;
providing wireless communication information from the intrinsically-safe handheld field maintenance tool to a remote device, the wireless communication information being indicative, at least, of alphanumeric display information;
receiving the wireless communication information at the remote device and rendering at least an alphanumeric display by the remote device based on the wireless communication information;
wherein the intrinsically-safe handheld field maintenance tool is physically coupled to the field device; and
receiving the wireless communication information from the remote device and causing the I/O module to inject at least one keystroke based on the received wireless communication information.

2. The method of claim 1, wherein the wireless communication information is in accordance with a Bluetooth specification.

3. The method of claim 1, wherein the intrinsically-safe handheld field maintenance tool is located in a hazardous location.

4. The method of claim 1, wherein the display rendered by the remote device is larger than the local display.

5. The method of claim 1, wherein the local display of the handheld field maintenance tool is mirrored to the display rendered by the remote device.

6. The method of claim 5, wherein the mirroring is done in real-time.

7. The method of claim 1, wherein individual keystrokes on the intrinsically-safe handheld field maintenance tool are rendered on the display of the remote device.