Abstract:
There is disclosed a locator/control arrangement for locating and controlling underground movement of a boring tool which is operated from a drill rig. An associated method is also disclosed. The boring tool includes means for emitting a locating signal. The locator/control arrangement includes a portable device for generating certain information about the position of the boring tool in response to and using the locating signal. In addition, the portable device includes means for generating command signals in view of the generated certain information and for transmitting the command signals to the drill rig. Means located at the drill rig then receives the command signals whereby the command signals can be used to control the boring tool. In one feature, the means located at the drill rig for receiving the command signals may include means for indicating the command signals to a drill rig operator. In another feature, the means located at the drill rig for receiving the command signals may include means for automatically executing the command signals at the drill rig in a way which eliminates the need for a drill rig operator. Drill rig monitoring means may be provided for monitoring particular operational parameters of the drill rig. Such monitoring is particularly useful when a drill rig operator is not needed.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    The present invention relates generally to underground boring tool guidance and, more particularly, to a remote walk over locator/controller configured for determining the underground location of a boring tool and for remotely issuing control commands to a drill rig which is operating the boring tool.  
           [0002]    Installing underground utility cable using a steerable boring tool is well known in the art. Various examples are described in U.S. Pat. Nos. 5,155,442, 5,337,002, 5,444,382 and 5,633,589 as issued to Mercer et al (collectively referred to herein as the Mercer Patents), all of which are incorporated herein by reference. An example of the prior art Mercer technique is best illustrated in FIG. 1 herein which corresponds to FIG. 2 in the Mercer Patents. For purposes of clarity, the reference numerals used in the Mercer Patents have been retained herein for like components.  
           [0003]    As seen in FIG. 1, an overall boring machine  24  is positioned within a starting pit  22  and includes a length of drill pipe  10 , the front end of which is connected to the back end of a steerable boring head or tool  28 . As described in the Mercer Patents, the boring tool includes a transmitter for emitting a dipole magnetic field  12  which radiates in front of, behind and around the boring tool, as illustrated in part in FIG. 1. A first operator  20  positioned at the starting pit  22  is responsible for operating the boring machine  24 ; that is, he or she causes the machine to let out the drill pipe, causing it to push the boring tool forward. At the same time, operator  20  is responsible for steering the boring tool through the ground. A second locator/monitor operator  26  is responsible for locating boring tool  28  using a locator or receiver  36 . The boring tool is shown in FIG. I being guided beneath an obstacle  30 . The locator/monitor operator  26  holds locator  36  and uses it to locate a surface position above tool head  28 . Once operator  26  finds this position, the locator  36  is used to determine the depth of tool head  28 . Using the particular locator of the present invention, operator  26  can also determine roll orientation and other information such as yaw and pitch. This information is passed on to operator  20  who then may use it to steer the boring tool to its target. Unfortunately, this arrangement requires at least two operators in order to manage the drilling operation, as will be discussed further.  
           [0004]    Still referring to FIG. 1, current operation of horizontal directional drilling (HDD) with a walkover locating system requires a minimum of two skilled operators to perform the drilling operation. As described, one operator runs the drill rig and the other operator tracks the progress of the boring tool and determines the commands necessary to keep the drill on a planned course. In the past, communication between the two operators has been accomplished using walkie-talkies. Sometimes hand signals are used on the shorter drill runs. However, in either instance, there is often confusion. Because an operating drill rig is typically quite noisy, the rig noise can make it difficult, if not impossible, to hear the voice communications provided via walkie-talkie. Moreover, both the walkie-talkie and the hand signals are awkward since the operator of the drill rig at many times has both of his hands engaged in operation of the drill rig. Confused steering direction can result in the drill being misdirected, sometimes with disastrous results.  
           [0005]    The present invention provides a highly advantageous boring tool control arrangement in which an operator uses a walk-over locator unit that is configured for remotely issuing control commands to a drill rig. In this way, problems associated with reliable communications between two operators are eliminated. In addition, other advantages are provided, as will be described hereinafter.  
         SUMMARY OF THE INVENTION  
         [0006]    As will be described in more detail hereinafter, there is disclosed herein a locator/control arrangement for locating and controlling underground movement of a boring tool which is operated from a drill rig. An associated method is also disclosed. The boring tool includes means for emitting a locating signal. In accordance with the present invention, the locator/control arrangement includes a portable device for generating certain information about the position of the boring tool in response to and using the locating signal. In addition to this means for generating certain information about the position of the boring tool, the portable device also includes means for generating command signals in view of this certain information and for transmitting the command signals to the drill rig. Means located at the drill rig then receives the command signals whereby the command signals can be used to control the boring tool.  
           [0007]    In accordance with one aspect of the present invention, the means located at the drill rig for receiving the command signals may include means for indicating the command signals to a drill rig operator.  
           [0008]    In accordance with another aspect of the present invention, the means located at the drill rig for receiving the command signals may include means for automatically executing the command signals at the drill rig in a way which eliminates the need for a drill rig operator.  
           [0009]    In accordance with still another aspect of the present invention, drill rig monitoring means may be provided for monitoring particular operational parameters of the drill rig. In response to the particular operational parameters, certain data may be generated which may include a warning that one of the parameters has violated an acceptable operating value for that parameter. In one feature, the certain data regarding the operational parameters may be displayed at the drill rig. In another feature, the certain data regarding the operational parameters may be displayed on the portable device. The latter feature is highly advantageous in embodiments of the invention which contemplate elimination of the need for a drill rig operator. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]    The present invention may be understood by reference to the following detailed description taken in conjunction with the drawings, in which:  
         [0011]    [0011]FIG. 1 is a partially broken away elevational and perspective view of a boring operation described in the previously recited Mercer Patents.  
         [0012]    [0012]FIG. 2 is an elevational view of a boring operation being performed in accordance with the present invention in which a portable locator/controller is used.  
         [0013]    [0013]FIG. 3 is a diagrammatic perspective view of the portable locator/controller which is used in the boring operation of FIG. 2, shown here to illustrate details of its construction.  
         [0014]    [0014]FIG. 4 is a partial block diagram illustrating details relating to the configuration and operation of the portable locator/controller of FIG. 3.  
         [0015]    [0015]FIG. 5 is a partial block diagram illustrating details relating to the configuration and operation of one arrangement of components located at the drill rig for receiving command signals transmitted from the portable locator/controller of the present invention.  
         [0016]    [0016]FIG. 6 is a partial block diagram illustrating details relating to the configuration and operation of another arrangement of components located at the drill rig for receiving command signals transmitted from the portable locator/controller and for, thereafter, executing the commands signals so as to eliminate the need for a drill rig operator. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0017]    Turning again to the drawings, attention is immediately directed to FIG. 2 which illustrates a horizontal boring operation being performed using a boring/drilling system generally indicated by the reference numeral  70 . The drilling operation is performed in a region of ground  72  including a boulder  74 . The surface of the ground is indicated by reference numeral  76 .  
         [0018]    System  70  includes a drill rig  78  having a carriage  80  received for movement along the length of an opposing pair of rails  82  which are, in turn, mounted on a frame  84 . A conventional arrangement (not shown) is provided for moving carriage  80  along rails  82 . During drilling, carriage  80  pushes a drill string  86  into the ground and, further, is configured for rotating the drill string while pushing, as will be described. The drill string is made up of a series of individual drill string sections or pipes  88 , each of which includes a suitable length such as, for example, ten feet. Therefore, during drilling, sections  88  must be added to the drill string as it is extended or removed from the drill string as it is retracted. In this regard, drill rig  78  may be configured for automatically adding or removing the drill string sections as needed during the drilling operation. Underground bending of the drill string sections enables steering, but has been exaggerated for illustrative purposes.  
         [0019]    Still referring to FIG. 2, a boring tool  90  includes an asymmetric face  92  and is attached to the end of drill string  86 . Steering of the boring tool is accomplished by orienting face  92  of the boring tool (using the drill string) such that the boring tool is deflected in the desired direction. Boring tool  90  includes a mono-axial antenna such as a dipole antenna  94  which is driven by a transmitter  96  so that a magnetic locating signal  98  is emanated from antenna  94 . Power may be supplied to transmitter  96  from a set of batteries  100  via a power supply  102 . A control console  104  is provided for use in controlling and/or monitoring the drill rig. The control console includes a drill rig telemetry transceiver  106  connected with a telemetry receiving antenna  108 , a display screen  110 , an input device such as a keyboard  112 , a processor  114 , and a plurality of control levers  116  which, for example, hydraulically control movement of carriage  80  along with other relevant functions of drill rig operation.  
         [0020]    Still referring to FIG. 2, in accordance with the present invention, drilling system  70  includes a portable locator/controller  140  held by an operator  141 . With exceptions to be noted, locator  140  may be essentially identical to locator  36 , as described in the Mercer Patents.  
         [0021]    Turning to FIG. 3 in conjunction with FIG. 2, the same reference numerals used to describe locator  36  in the Mercer Patents have been used to designate corresponding components in locator/controller  140 . In order to understand and appreciate the present invention, the only particular components of locator  36  that form part of locator  140  and that are important to note here are the antenna receiver arrangement comprised of orthogonal antennas  122  and  124  and associated processing circuitry for measuring and suitably processing the field intensity at each antenna and roll/pitch antenna  126  and associated processing circuitry  128  for measuring the pitch and roll of the boring tool. Inasmuch as the Mercer patents fully describe the process by which locator  140  is used to find the position of boring tool  90 , the reader is referred to the patents for a detailed description of the locating method.  
         [0022]    Referring to FIGS.  2 - 4 , in accordance with the present invention, locator/controller  140  includes a CPU  144 , interfaced with a remote telemetry transceiver  146 , a joystick  148  and a display  150 . Remote transceiver  146  is configured for two-way communication with drill rig transceiver  106  via an antenna  152 . Joystick  148  is positioned in a convenient location for actuation by operator  141 . In accordance with one highly advantageous feature of the present invention, operator  141  is able to remotely issue control commands to drill rig  78  by actuating joystick  148 . Commands which may be issued to the drill rig by the operator include, but are not limited to (1) roll orientation for steering direction purposes, (2) “advance ”and (3) “retract.” It should be appreciated that the ability to issue these commands from locator/controller  140 , in essence, provides for complete boring tool locating and control capability from locator/controller  140 . A locator/controller command is implemented using CPU  144  to read operator actuations of the joystick, interpret these actuations to establish the operator&#39;s intended command, and then transfer the command to remote transceiver  146  for transmission to the command drill rig telemetry transceiver  106  at the drill rig, as will be described immediately hereinafter.  
         [0023]    Still referring FIGS.  2 - 4 , control commands are entered by using display  150  in conjunction with joystick  148 . Display  150  includes an enhanced roll orientation/steering display  154  having a clock face  156  which shows clock positions  1  through  12 . These clock positions represent the possible steering directions in which boring tool  90  may be set to travel. That is, the axis of the boring tool is assumed to extend through a center position  158  of the clock display and perpendicular to the plane of the figure. The desired roll orientation is established by moving joystick  148  either to the left or right. As the joystick is moved, a desired roll orientation pointer  160  incrementally and sequentially moves between the clock positions. For instance, if the desired roll pointer was initially located at the 12 o&#39;clock position (not shown), the locator/controller operator may begin moving it to the 3 o&#39;clock position by moving and holding the joystick to the right. CPU  144  detects the position of the joystick and incrementally moves the desired roll pointer to the 1 o&#39;clock, then 2 o&#39;clock, and finally the 3 o&#39;clock position. At this point, the operator releases the joystick. Of course, at the 3 o&#39;clock position, the command established is to steer the boring tool to the right. Similarly, the 6 o&#39;clock position corresponds to steering downward, the 9 o&#39;clock position corresponds to steering to the left and the 12 o&#39;clock position corresponds to steering upward. As mentioned previously, steering is accomplished by setting face  92  of the boring tool in an appropriate position in accordance with the desired roll of the boring tool. With regard to boring tool steering, it is to be understood that boring tool steering has been implemented using concepts other than that of roll orientation and that the present invention is readily adaptable to any steering method either used in the prior art or to be developed.  
         [0024]    Having established a desired steering direction, operator  141  monitors an actual roll orientation indicator  162 . As described in the Mercer patents, roll orientation may be measured within the boring tool by a roll sensor (not shown). The measured roll orientation may then be encoded or impressed upon locating signal  90  and received by locator/controller  140  using antenna  126 . This information is input to CPU  144  as part of the “Locator Signal Data” indicated in FIG. 4. CPU  144  then causes the measured/actual roll orientation to be displayed by actual roll orientation indicator  162 . In the present example, operator  141  can see that the actual roll orientation is at the 2 o&#39;clock position. Once the desired roll orientation matches the actual roll orientation, the operator will issue an advance command by moving joystick  148  forward. Advancement or retraction commands for the boring tool can only be maintained by continuously holding the joystick in the fore or aft positions. That is, a stop command is issued when joystick  148  is returned to its center position. If the locating receiver were accidentally dropped, the joystick would be released and drilling would be halted. This auto-stop feature will be further described in conjunction with a description of components which are located at the drill rig.  
         [0025]    Still referring to FIGS.  2 - 4 , a drill string status display  164  indicates whether the drill rig is pushing on the drill string, retracting it or applying no force at all. Information for presentation of drill string status display  164  along with other information to be described is transmitted from transceiver  106  at the drill rig and to transceiver  146  in the locator/controller. Once the boring tool is headed in a direction which is along a desired path, operator  141  can command the boring tool to proceed straight. As previously described, for straight drilling, the drill string rotates. In the present example, after having turned the boring tool sufficiently to the right, the operator may issue a drill straight command by moving joystick  148  to the left and, thereafter, immediately back to the right. These actuations are monitored by CPU  144 . In this regard, it should be appreciated that CPU  144  may respond to any suitable and recognizable gesture for purposes of issuance of the drill straight command or, for that matter, CPU  144  may respond to other gestures to be associated with other desired commands. In response to recognition of the drill straight gesture, CPU  144  issues a command to be transmitted to the drill rig which causes the drill string to rotate during advancement. At the same time, CPU  144  extinguishes desired roll orientation indicator  160  and actual roll orientation indicator  162 . In place of the roll orientation indicators, a straight ahead indication  170  is presented at the center of the clock display which rotates in a direction indicated by an arrow  172 . It is noted that the straight ahead indication is not displayed in the presence of steering operations which utilize the desired or actual roll orientation indicators. Alternatively, in order to initiate straight drilling, the locator/controller operator may move the joystick to the left. In response, CPU  144  will sequentially move desired roll indicator  160  from the 3 o&#39;clock position, to the 2 o&#39;clock position and back to the 1 o&#39;clock position. Thereafter, the desired roll indicator is extinguished and straight ahead indication  170  is provided. Should the operator continue to hold the joystick to the left, the 12 o&#39;clock desired roll orientation (i.e., steer upward) would next be presented.  
         [0026]    In addition to the features already described, display  150  on the locator/controller of the present invention may include a drill rig status display  174  which presents certain information transmitted via telemetry from the drill rig to the locator/controller. The drill rig status display and its purpose will be described at an appropriate point below. For the moment, it should be appreciated that commands transmitted to drill rig  78  from locator/controller  140  may be utilized in several different ways at the drill rig, as will be described immediately hereinafter.  
         [0027]    Attention is now directed to FIGS. 2 and 5. FIG. 5 illustrates a first arrangement of components which are located at the drill rig in accordance with the present invention. As described, two-way communications are established by the telemetry link formed between transceiver  106  at the drill rig and transceiver  146  at locator/controller  140 . In this first component arrangement, display  110  at the drill rig displays the aforedescribed commands issued from locator/controller  140  such that a drill rig stationed operator (not shown) may perform the commands. Display  110 , therefore, is essentially identical to display  150  on the locator/controller except that additional indications are shown. Specifically, a push or forward indication  180 , a stop indication  182  and a reverse or retract indication  184  are provided. It is now appropriate to note that implementation of the aforedescribed auto-stop feature should be accomplished in a fail-safe manner. In addition to issuing a stop indication when joystick  148  is returned to its center position, the drill rig may require periodic updates and if the updates were not timely, stop indication  182  may be displayed automatically. Such updates would account for loss of the telemetry link between the locator/controller and the drill rig.  
         [0028]    Still referring to FIGS. 2 and 5, the forward, stop and retract command indications eliminate the need for other forms of communication between the drill rig operator and the locator/controller operator such as the walkie-talkies which were typically used in the prior art. At the same time, it should be appreciated that each time a new command is issued from the locator/controller, an audible signal may be provided to the drill rig operator such that the new command does not go unnoticed. Of course, the drill rig operator must also respond to roll commands according to roll orientation display  154  by setting the roll of the boring tool to the desired setting. In this regard, it should be mentioned that a second arrangement (not shown) of components at the drill rig may be implemented with a transmitter at the locator/controller in place of transceiver  152  and a receiver at the drill rig in place of transceiver  106  so as to establish a one-way telemetry link from the boring tool to the drill rig. However, in this instance, features such as operations status display  174  and drill string status display  164  cannot be provided at the locator/controller.  
         [0029]    It should be appreciated that the first and second component arrangements described with regard to FIG. 5 contemplate that the drill rig operator may perform tasks including adding or removing drill pipe sections  88  from the drill string and monitoring certain operational aspects of the operation of the drill rig. For example, the drill rig operator should insure that drilling mud (not shown) is continuously supplied to the boring tool so that the boring tool does not overheat whereby the electronics packaged housed therein would be damaged. Drilling mud may be monitored by the drill rig operator using a pressure gauge or a flow gauge. As another example, the drill rig operator may monitor the push force being applied to the drill string by the drill rig. In the past, push force was monitored by “feel” (i e., reaction of the drill rig upon pushing). However, push force may be directly measured, for instance, using a pressure or force gauge. If push force becomes excessive as a result of encountering an underground obstacle, the boring tool or drill string may be damaged. As a final example, the drill rig operator may monitor any parameters impressed upon locating signal  98  such as, for instance, boring tool temperature, battery status, roll, pitch and proximity to an underground utility. In this latter regard, the reader is referred to U.S. application Ser. No. 08/643,209 entitled A SYSTEM INCLUDING AN ARRANGEMENT FOR TRACKING THE POSITIONAL RELATIONSHIP BETWEEN A BORING TOOL AND ONE OR MORE BURIED LINES AND METHOD which is incorporated herein by reference.  
         [0030]    Referring to FIG. 5, another feature may be incorporated in the first and second component arrangements which is not requirement, but which nonetheless is highly advantageous with regard to drill rig status monitoring performed by the drill rig operator. Specifically, a rig monitor section  190  may be included for monitoring the aforementioned operational parameters such as drilling mud, push force and any other parameters of interest As previously described, proper monitoring of these parameters is critical since catastrophic equipment failures or damage to underground utilities can occur when these parameters are out of range. In accordance with this feature, processor  114  receives the status of the various parameters being monitored by the rig monitor section and may provide for visual and/or aural indications of each parameter. Visual display occurs on operations status display  174 . The display may provide real time indications of the status of each parameter such as “OK”, as shown for drilling mud and push force, or an actual reading may be shown as indicated for the “Boring Tool Temperature”. Of course, visual warnings in place of “OK” may be provided such as, for example, when excessive push force is detected. Audio warning may be provided by an alarm  192  in the event that threshold limits of any of the monitored parameters are violated. In fact, the audio alarm may vary in character depending upon the particular warning being provided. It should be mentioned that with the two-way telemetry link between the drill rig and locator/controller according to the aforedescribed first component arrangement, displays  164  and  174  may advantageously form part of overall display  150  on locator/controller  140 , as shown in FIG. 4. However, such operational status displays on the locator/controller are considered as optional in this instance since the relevant parameters may be monitored by the drill rig operator. The full advantages of rig monitor section  190  and associated operations status display  174  will come to light in conjunction with a description of a fully automated arrangement to be described immediately hereinafter.  
         [0031]    Referring to FIGS. 2 and 6, in accordance with a third, fully automated arrangement of the present invention, a drill rig control module  200  is provided at drill rig  78 . Drill rig control module  200  is interfaced with processor  114 . In response to commands received from locator/controller  140 , processor  114  provides command signals to the drill rig control module. The latter is, in turn, interfaced with drill rig controls  116  such that all required functions may be actuated by the drill rig control module. Any suitable type of actuator (not shown) may be utilized for actuation of the drill rig controls. In fact, manual levers may be eliminated altogether in favor of actuators. Moreover, the actuators may be distributed on the drill rig to the positions at which they interface with the drill rig mechanism. For reasons which will become apparent, this third arrangement requires two-way telemetry between the drill rig and locator/controller such that drill string status display  164  and operations status display  174  are provided as part of display  150  on the locator/controller. At the same time, these status displays are optional on display  110  at the drill rig.  
         [0032]    Still referring to FIGS. 2 and 6, in accordance with the present invention, using locator/controller  140 , operator  141  is able to issue control commands which are executed by the arrangement of FIG. 6 at the drill rig. Concurrent with locating and controlling the boring tool, operator  141  is able to monitor the status of the drill rig using display  150  on the locator/controller. In this regard, display  174  on the locator/controller also apprises the operator of automated drill rod loading or unloading with indications such as, for example, “Adding Drill Pipe.” In this manner, the operator is informed of reasons for normal delays associated with drill string operations. Since push force applied by the drill rig to the drill string is a quite critical parameter, the present invention contemplates a feature (not shown) in which push force is measured at the drill rig and, thereafter, used to provide push force feedback to the operator via joystick  148  for ease in monitoring this critical parameter. The present invention contemplates that this force feedback feature may be implemented by one of ordinary skill in the art in view of the teaching provided herein. Still other parameters may be monitored at the drill rig and transmitted to locator/controller  140 . In fact, virtually anything computed or measured at the drill rig may be transmitted to the locator/controller. For example, locator/controller  140  may display (not shown) deviation from a desired path. Path deviation data may be obtained, for example, as set forth in U.S. Pat. No. 5,698,981 entitled BORING TECHNIQUE which is incorporated herein by reference. Alternatively, path deviation data may be obtained by using a magnetometer (not shown) positioned in the boring tool in combination with measuring extension of the drill string. With data concerning the actual path taken by the boring tool, the actual path can be examined for conformance with minimum bend radius requirements including those of the drill string or those of the utility line which, ultimately, is to be pulled through the completed bore. That is, the drill string or utility line can be bent too sharply and may, consequently, suffer damage. If minimum bend radius requirements for either the drill string or utility are about to be violated, an appropriate warning may be transmitted to locator/controller  140 . It should be appreciated that with the addition of the drill rig control module, complete remote operation capability has been provided. In and by itself, it is submitted that integrated locating capability and remote control of a boring tool has not been seen heretofore and is highly advantageous. When coupled with remote drill rig status monitoring capability, the present invention provides remarkable advantages over prior art horizontal directional drilling systems.  
         [0033]    The advantages of the fully automated embodiment of the present invention essentially eliminate the need for a skilled drill rig operator. In this regard, it should be appreciated that the operator of a walkover locator is, in most cases, knowledgeable with respect to all aspects of drill rig operations. That is, most walkover locator operators have been trained as drill rig operators and then advance to the position of operating walkover locating devices. Therefore, such walkover locator operators are well versed in drill rig operation and welcome the capabilities provided by the present invention.  
         [0034]    It should be understood that an arrangement for remotely controlling and tracking an underground boring tool may be embodied in many other specific forms and produced by other methods without departing from the spirit or scope of the present invention. Therefore, the present examples are to be considered as illustrative and not restrictive, and the invention is not to be limited to the details given herein, but may be modified within the scope of the appended claims.