Electric cable management for a mobile machine

A method of managing movement of an electric cable that is configured to provide power to a mobile machine. The method includes determining an initial boundary of an isolation zone in which the cable lies, for a first location of the machine. The initial boundary is divided into a first static boundary and a first dynamic boundary. The first static boundary surrounds a static isolation sub-zone of the isolation zone, and the first dynamic boundary surrounds a dynamic isolation sub-zone of the isolation zone. A second dynamic boundary surrounding the dynamic isolation sub-zone is determined, based on a second location of the machine when the machine moves from the first location to the second location, such that the cable lies within the second dynamic boundary. The first static boundary is maintained when the machine is in the second location.

TECHNICAL FIELD

The present disclosure is directed to electric cable management for a mobile machine, and more particularly to electric cable management between movements of the machine.

BACKGROUND

A moving or mobile machine, such as an earthmoving machine, an excavation-type machine, a mining machine, or the like, may be employed for mining or another earthmoving operation. The machine may employ large earthmoving, excavating, drilling, or mining equipment, such as an electric mining shovel, configured to dig and/or load earthen material from a worksite, such as an open-pit mine, to one or more large off-road haulage units, such as off-highway trucks that may be driven by a driver or autonomously or semi-autonomously controlled. The shovel may be electrically powered and may receive power from a high-voltage cable that is tethered to the rear of the machine. The electric cable may lie across the ground of the worksite during operation of the shovel. When the shovel swings between a digging location and a loading location where the shovel loads a mobile vehicle (such as an off-highway truck), the cable may be dragged across the ground and the location of the cable may change relative to the ground. Similarly, the cable may move when the shovel moves, such as when the shovel moves from one digging location to a subsequent digging location.

Off-highway trucks may navigate to and from the location of the shovel in order to transport the earthen material from the worksite. A driver of the off-highway truck must avoid contact with the electric cable so as to prevent damage to both the electric cable and the truck. For similar reasons, an autonomous truck must avoid contact with the electric cable. However, mobility and navigation around the electric cable may be difficult because the driver of the truck may be unable to see the ground, and thus may be unable to locate the electric cable near the truck. In the case of the autonomous truck, the location of the cable must be determined since there is no driver.

FIGS. 1A and 1Bshow examples of related systems in which the location of the electric cable is managed. As shown inFIG. 1A, when electric mining shovel110is located at digging location A, the boundary of isolation zone120in which electric cable130lies on the ground is determined. Specifically, the boundary of isolation zone120extends from adjacent the high-voltage power source140, to which one end of electric cable130is connected, to shovel110, to which the other end of electric cable130is connected. The boundary of isolation zone120may be marked with visual markers (e.g., safety cones, fencing, etc.), and/or the coordinate locations of the boundary of isolation zone120may be determined (e.g., with global position system coordinates, sensors, etc.), so that a driver-operated and/or autonomous vehicle (e.g., a truck loaded with earthen material removed by shovel110) may be prevented from driving over electric cable130.

As shown inFIG. 1B, when electric mining shovel110is moved to another, adjacent digging location, such as from digging location A to digging location B, the boundary of a different isolation zone140, in which electric cable130now lies on the ground, must be determined. Thus, every time shovel110moves to a different digging location, the boundary of another isolation zone in which electric cable130lies on the ground must be determined. This boundary determination is a time-consuming and labor intensive procedure, and operation of driver-operated and autonomous vehicles around shovel110must be halted until the boundary of the isolation zone is determined, to ensure that electric cable130is not run over by any of the vehicles operating in the vicinity of shovel110.

SUMMARY

One disclosed embodiment relates to a method of managing movement of an electric cable that is configured to provide power to a mobile machine. The method includes determining an initial boundary of an isolation zone in which the cable lies, for a first location of the machine. The initial boundary is divided into a first static boundary and a first dynamic boundary. The first static boundary surrounds a static isolation sub-zone of the isolation zone, and the first dynamic boundary surrounds a dynamic isolation sub-zone of the isolation zone. A second dynamic boundary surrounding the dynamic isolation sub-zone is determined, based on a second location of the machine when the machine moves from the first location to the second location, such that the cable lies within the second dynamic boundary. The first static boundary is maintained when the machine is in the second location.

Another embodiment relates to a method of managing movement of an electric cable that is configured to provide power to a mobile machine. A boundary of a power-side isolation zone in which the cable extends from a power source to a first pole, is determined. A boundary of a machine-side isolation zone in which the cable extends from a second pole to the machine, is determined. A location of an anchor line that divides the boundary of the machine-side isolation zone into a first static boundary and a first dynamic boundary, is determined. The first static boundary surrounds a static isolation sub-zone of the isolation zone, and the first dynamic boundary surrounds a dynamic isolation sub-zone of the isolation zone. A second dynamic boundary surrounding the dynamic isolation sub-zone is determined, based on the location on the anchor line and on a second location of the machine when the machine moves to the second location, such that the cable lies within the second dynamic boundary. The first static boundary is maintained when the machine is in the second location.

A further disclosed embodiment relates to a tangible, computer-readable storage medium storing a program that, when executed by a processor of a computer, performs a method of managing movement of an electric cable that is configured to provide power to a mobile machine. The method includes determining an initial boundary of an isolation zone in which the cable lies, for a first location of the machine. A location of an anchor line that divides the initial boundary into a first static boundary and a first dynamic boundary is determined. The first static boundary surrounds a static isolation sub-zone of the isolation zone, and the first dynamic boundary surrounds a dynamic isolation sub-zone of the isolation zone. A second dynamic boundary surrounding the dynamic isolation sub-zone is determined, based on the location on the anchor line and on a second location of the machine when the machine moves from the first location to the second location, such that the cable lies within the second dynamic boundary. The first static boundary is maintained when the machine is in the second location.

DETAILED DESCRIPTION

FIGS. 2A-2Care diagrammatic illustrations of electric cable location management when a moving or mobile machine210operating on a worksite300moves among first, second, and third locations on worksite300. Machine210may be any type of machine capable of excavating earth, such as an excavator machine, a drilling machine, an electric mining shovel machine, or the like. As shown in the figures, machine210may be self-propelled and include a rotatable car body230connected to an undercarriage240. Machine210may also include a boom250, a stick260, and an earthmoving tool270. Boom250may be pivotally mounted on machine210by a boom pivot pin. Stick260may be pivotally connected to the free end of boom250at a stick pivot pin. Earthmoving tool270may be a power shovel, a bucket, or the like, and may be pivotally attached to stick260at a bucket pivot pin and configured to dig, scoop, and/or load material, such as but not limited to ore, coal, or other minerals. A cable400, e.g., a set of high-voltage cables, may be engaged with and tethered from one or more large electric motors (not shown) on the rear of machine210. Cable400may be configured to provide electricity from a central high-voltage power source (not shown) to machine210so as to power the operation of machine210and earthmoving tool270. Machine210may be configured to travel along worksite300, such as, for example, an open-pit mine. Car body230may rotate so that earthmoving tool270may excavate and load material from various locations of worksite300along the path of rotation. Earthmoving tool270may be configured to unload material to worksite equipment, such as a vehicle500, so that vehicle500may transport material from worksite300.

FIG. 2Ashows machine210at a first digging or working location on worksite300. As shown in the figure, worksite300may include one or more isolation zones or areas in which cable400lies on the ground. Vehicles, such as vehicle500, may be kept out of the isolation zones, so that vehicle500does not run over cable400. Running over cable400may result in damage to cable400and/or vehicle500. Once boundaries are determined for the isolation zones, the boundaries may be marked by visual markers (e.g., safety cones, fencing, etc.) in order to provide one or more visual cues to the driver of vehicle500to stay outside of the isolation zones. Alternately, or in conjunction with the visual markers, coordinate locations of the boundaries defining the isolation zones may be determined. These coordinate locations may be provided to driver-controlled and/or autonomous vehicles. When the driver-controlled vehicle drives into the isolation zone, an audible, a visual, or another type of alarm may be activated, alerting the driver that the vehicle is within the isolation zone. Or, the autonomous vehicle may receive these coordinate locations and be prohibited from driving into the isolation zones.

The boundary of a first isolation zone (power-side isolation zone)610may encompass cable400where it lies on the ground between a power source and a support pole. Specifically, the boundary of first zone610may extend from the high-voltage power source (not shown), to which one end of cable400is connected, to a nonshovel-side pole620that supports a portion of cable400off the ground. Vehicles, such as vehicle500, should remain outside first zone610to prevent damage to cable400and/or vehicle500. First zone610may be provided as a static isolation zone, since movement of machine210between different digging or working positions on worksite300does not result in a change of location of cable400within first zone610and does not result in cable400being moved outside of the original boundary of first zone610. Thus, the boundary of first zone610does not change as a result of movement of machine210between different digging locations.

The boundary of second isolation zone630(machine-side isolation zone) may encompass cable400where it lies on the ground between another support pole and machine210. Specifically, the boundary of second zone630may extend from machine210, to which the other end of electric cable400is connected, to a shovel-side pole640that supports another portion of cable400off the ground. Similar to first zone610, vehicles including vehicle500should remain outside of the boundary of second zone630to prevent damage to cable400and/or vehicle500. Second zone630may be provided as a dynamic isolation zone, since movement of machine210to another digging location on worksite300does, in fact, result in a change of location of cable400within at least some portion of second zone630, as well as result in cable400moving outside of at least a portion of the original boundary of second zone630. Thus, to at least some extent, the boundary of second zone630must change as a result of movement of machine210between digging locations.

Second zone630is divided into sub-zone650and sub-zone660. The boundary of sub-zone650may encompass cable400where it lies on the ground from shovel-side pole640to a location where movement of machine210does not result in movement of cable400outside of sub-zone650. In other words, sub-zone650may be provided as a static isolation zone, since movement of machine210to another digging location on worksite300does not result in movement of cable400outside of the original boundary of second zone630or outside of the original boundary of sub-zone650. As a result, during movement of machine210between digging locations on worksite300, the boundary of sub-zone650does not change, and does not need to be redetermined.

As shown in the figures, sub-zone650may extend from shovel-side pole640to an anchor line670, which is an imaginary line on worksite300. Anchor line670may be defined by two anchor points, a line through which forms an end of sub-zone650farthest from shovel-side pole640. These two points, and thus the location of anchor line670, may be chosen such that an area of sub-zone650, which is a static isolation zone, is maximized, while the area of sub-zone660that is a dynamic isolation zone (as described in more detail below) is minimized.

The boundary of sub-zone660may encompass cable400where it lies on the ground from machine210to the location where movement of machine210to another digging location (such as a relatively near digging location) does, in fact, result in movement of cable400outside of the original boundary of sub-zone660. In other words, sub-zone660may be provided as a dynamic isolation zone, since movement of machine210to another, adjacent digging location on worksite300does result in cable400moving outside of the original boundary of sub-zone660, and therefore the boundary of sub-zone660does change as a result of movement of machine210between adjacent digging locations.

In order to permit vehicles, such as vehicle500, to travel between first and second isolation zones610and630, the first and second isolation zones610and630may be separated a sufficient distance from one another. Thus, nonshovel-side pole620and shovel-side pole640, each of which supports cable400off of the ground, may be disposed far enough apart to permit vehicles, such as vehicle500, to pass therebetween.

FIG. 2Bshows machine210having moved from the first digging location to the second digging or working location on worksite300. Even as a result of movement of machine210on worksite300, the boundary of first zone610, which is a static isolation zone, need not be redetermined. Further, the boundary of sub-zone650(that is a static isolation zone) of second zone630need not be redetermined. Only the new boundary of sub-zone660(that is a dynamic isolation zone), in which the location of cable400moves outside of the original boundary of the sub-zone, needs to be determined. As discussed above, the area of sub-zone660is minimized as the result of the area of sub-zone650being maximized.

FIG. 2Cshows machine210having moved from the second digging location to a third digging or working location on worksite300. When machine210moves a sufficient distance from a prior digging or working location to a subsequent location, it may eventually become necessary or desirable to relocate or redetermine the boundary of sub-zone650of second isolation zone630, since cable400may no longer lie within sub-zone650.

As shown in the figure, even as a result of movement of machine210on worksite300, the boundary of first zone610, which is a static isolation zone, still need not be redetermined. But, the boundary of sub-zone650of second zone630does need to be redetermined, as cable400is moved outside of the original boundary of sub-zone650. Sub-zone650still remains a static isolation zone because after the new boundary of sub-zone650is determined, cable400does not move outside of the new boundary of sub-zone650even when machine210moves to another subsequent digging or working location that is adjacent to the third location. Sub-zone660, however, remains a dynamic isolation zone, since cable400is expected to move outside of the new boundary of sub-zone660when machine210does move from the third location shown inFIG. 2Cto the another subsequent digging location.

INDUSTRIAL APPLICABILITY

As discussed above, the disclosure describes multiple isolation zones, separated from one another, in which electric cable400lies on the ground to provide power from the power source (not shown) to machine210. First isolation zone610may be a static isolation zone, in which cable400does not move as a result of movement of machine210from a first to a second working or digging location on worksite300. Thus, even when machine210moves between adjacent digging locations on worksite300, the boundary of first zone610does not change. As a result, visual markers indicating the boundary of first zone610, in which cable400lies on the ground, do not need to be moved or repositioned. Coordinate locations indicating the boundary of first zone610also need not be redetermined, so that no updated information needs to be provided to either a driver-controlled vehicle, such as to operate an alarm if the driver drives into the first zone610, and no updated information needs to be provided to an autonomously-controlled vehicle, such as to keep the vehicle from driving into first zone610.

Second isolation zone630, in contrast, may be at least in part a dynamic isolation zone, since movement of machine210from the first digging location to the second digging location on worksite300results in a movement of cable400outside of at least a portion of the original boundary of second zone630. Thus, at least a portion of the boundary of second zone630must change in order for second zone630to continue to define an isolation zone that completely encompasses cable400between shovel-side pole640and machine210. Because second zone630is a zone separate from first zone610, as discussed above the boundary of first zone610need not be redetermined even when machine210moves between adjacent or relatively near digging locations.

In order to reduce costs, labor requirement, time delays, and other disadvantages associated with determining an entire boundary of second zone630when machine210moves on worksite300, second zone630may be further divided into both a static isolation zone as well as a dynamic isolation zone. Sub-zone650may be a static isolation zone, defined between shovel-side pole640and anchor line670, with anchor line670being defined so that movement of machine210from the first digging location to the second digging location on worksite300does not result in cable400moving outside of the boundary of sub-zone650. Further, the location of anchor line670may be chosen so that the area of sub-zone650is maximized. Thus, visual markers indicating the boundary of sub-zone650, in which cable400lies on the ground, do not need to be moved or repositioned, and coordinate locations indicating the boundary also need not be redetermined, so that no updated information needs to be provided to either a driver-controlled vehicle to operate an alarm if the driver drives into sub-zone650, or to an autonomously-controlled vehicle to keep the vehicle from driving into sub-zone650. Thus, one or more of the above-discussed disadvantages of related cable management systems are avoided.

Sub-zone660may be a dynamic isolation zone defined between anchor line670and machine210. The aforementioned isolation zones and sub-zones may be arranged such that sub-zone660is the only zone outside of which cable400moves when machine210moves from the first digging location to the second digging location in worksite300. Further, because the location of anchor line670is chosen to maximize the area of static isolation sub-zone650, the area of dynamic isolation sub-zone660is minimized. Thus, the area of sub-zone660, for which the boundary must be redetermined when machine210moves between adjacent digging locations on worksite300, is minimized. The extent to which visual markers must be relocated and to which coordinate information must be redetermined is therefore also minimized.

In accordance with the disclosure, the location of electric cable400on worksite300, and thus the determination of the boundaries of zones610and630, may be managed as follows.

Nonshovel-side pole620and shovel-side pole640may be placed on worksite300. Nonshovel-side pole620is placed nearer the power source (i.e., on a “nonshovel side” of the worksite300), while shovel-side pole640is placed nearer machine210(i.e., on a “shovel side” of the worksite300). Poles620and640may be disposed a sufficient distance from one another to permit worksite vehicles, such as vehicle500, to pass therebetween. Absolute or relative positions of poles620and640may be determined and recorded, such as by using global positioning system coordinates, or by another method.

Cable400is run on the ground from the power source to nonshovel-side pole620, and nonshovel-side pole620holds a portion of cable400off of the ground. The portion of cable400that is held off the ground is connected to shovel-side pole640, such that cable400does not lay on the ground between poles620and640. Cable400lies on the ground and is run from shovel-side pole640to machine210, which is in a first digging or working location, such as is shown inFIG. 2A.

Visual markers, such as safety cones, fencing, etc., may be placed adjacent or around cable400from the power source to nonshovel-side pole620, and from shovel-side pole640to machine210.

The boundary is determined for each of first area610and second area630. Absolute or relative positions of the boundaries may be determined, such as by using global positioning system coordinates, or any other method. For example, the boundary may be manually determined, for example by driving a vehicle around cable400and/or around the visual markers, and noting the location of the vehicle at set time or distance intervals, and/or in response to operations of a driver. Alternately or in conjunction with this procedure, the location of cable400may be determined in accordance with the disclosure of U.S. Pat. No. 7,793,442, which is incorporated by reference herein in its entirety. It is to be understood that either or both of first zone610and second zone630need not define a closed area. For example, especially in the case of first zone610, the boundary of first zone610need not necessarily extend to the power source, which may be sufficiently far away from any expected digging locations of machine210such that any danger of a vehicle driving over cable400adjacent the power source is minimal.

The location of anchor line670is determined so that, based on the expected movement of cable400when machine210moves from its current digging location to an adjacent digging location (such as from the first digging location shown inFIG. 2Ato the second digging location shown inFIG. 2B), the boundary of sub-zone650does not need to be redetermined while at the same time the area of sub-zone660is prevented from being too large and impeding efficient use of worksite300, such as by taking up too much area of worksite300with the isolation zones. As discussed above, the location of anchor line670is determined so that the area of sub-zone650, which is a static isolation zone, is maximized, and the area of sub-zone660, which is a dynamic isolation zone, is minimized.

In accordance with the disclosure, the location of the two anchor points through which anchor line670runs may be determined by the operator of machine210. Specifically, the operator of machine210may survey the two anchor points, which create the anchor line670that defines the ends of sub-zones650and660. Surveying of one or both anchor points may be done by the operator of machine210relative to any point or points either on- or off-board machine210, such as but not limited to one or more points at which earthmoving tool270is placed. After anchor line670is determined, based on the location of anchor line670and the location of machine210, at least the area of the dynamic isolation sub-zone660may be determined by a computer on- or off-board of machine210, which includes a processor, memory, and other hardware, running an algorithm. Specifically, the algorithm may determine an expected path of movement for cable400based on a location of a portion of cable400adjacent anchor line670and an expected movement of machine210, and define an appropriately-sized area around this expected path of cable movement. By this process, the boundary of dynamic isolation sub-zone660may be automatically generated based on the location of machine210and the location of anchor line670, while the boundaries of static first isolation zone610and static isolation sub-zone650of second isolation zone630may have been manually determined.

The algorithm may use one or more parameters or inputs to automatically generate the boundary or boundaries of one or more of the zones610or630, or sub-zones650or660, based on, for example, an expected path of cable400. It is to be understood, however, that the specific use and implementation of the algorithm will be within the purview of one of ordinary skill in the art. By way of specific, non-limiting examples, the algorithm may use one or more of the following parameters or inputs: location of machine210; expected subsequent location of machine210; location of anchor line670; expected subsequent location of anchor line670; location(s) of one or both anchor points; expected subsequent location of one or both anchor points; overall length of cable400; length of cable400within sub-zone660; length of cable within second isolation zone630; location of a portion of cable400relative to one or more anchor points and/or anchor line670; expected subsequent location of a portion of cable400relative to one or more anchor points and/or anchor line670; current and/or expected subsequent tautness of cable400, at current and/or expected subsequent location of machine210; expected movement of cable400when machine210moves from current location to expected subsequent location; and/or another characteristic of cable400. It is to be understood, however, that one or more other parameters or inputs, with or without one or more of the above-presented exemplary parameters or inputs, may be used by the algorithm to automatically generate the boundary or boundaries of one or more of the zones610or630, or sub-zones650or660. It is to be further understood that one or more other parameters or inputs, with or without one or more of the above-presented exemplary parameters or inputs, may be used to automatically generate an expected envelope in which cable400is expected to move when machine210moves from a current location to an expected subsequent location. The expected envelope may then be enlarged to provide an additional factor of safety, thereby automatically generating the boundary or boundaries of one or more of the zones610or630, or sub-zones650or660.

When machine210moves from one digging location to another digging location, such as from the first position inFIG. 2Ato the second position inFIG. 2B, only the boundary of dynamic isolation sub-zone660may need to be redetermined. The boundaries of first zone610and sub-zone650of second zone630may not need to be redetermined. Absolute or relative positions of the new location of the boundary of sub-zone660may be determined, such as by using global positioning system coordinates, or any other method. For example, the boundary of dynamic isolation sub-zone660may be manually determined by driving a vehicle around cable400and the location of the vehicle may be noted at set time or distance intervals, and/or the location of the vehicle may be noted in response to operations of a driver.

In accordance with the disclosure, the boundary of dynamic isolation sub-zone660may be automatically generated. The location of the two anchor points through which anchor line670runs, as determined by the operator of machine210when machine210was in the first position shown inFIG. 2A, may still be used to define the ends of sub-zones650and660. Based on the unchanged-location of anchor line670and the new location of machine210, the area of the dynamic isolation sub-zone660may be redetermined, such as by the computer on- or off-board of machine210. The boundaries of static first isolation zone610and static isolation sub-zone650of second isolation zone630may not change and may not need to be redetermined.

When machine210moves from the second digging location, such as is shown inFIG. 2B, to the third digging location, such as shown inFIG. 2C, it may be necessary or desirable to relocate or redetermine the boundary of sub-zone650of second isolation zone630, even though the boundary of first zone610need not be redetermined. It may also be necessary or desirable to relocate or redetermine the boundary of sub-zone660of second isolation zone630. Absolute or relative positions of the new locations of the boundaries of either or both of static sub-zone650and dynamic sub-zone660may be determined, such as by using global positioning system coordinates, or any other method. For example, the boundary of sub-zones650and/or660may be manually determined by driving a vehicle around cable400and the location of the vehicle may be noted at set time or distance intervals, and/or the location of the vehicle may be noted in response to operations of a driver.

In accordance with the disclosure, the boundaries of either or both of static isolation sub-zone650and dynamic isolation sub-zone660may also be automatically generated. The location of shovel-side pole620may still be used to define the end of sub-zone650. Further, the new location for the two anchor points through which anchor line670runs may be determined by the operator of machine210. Specifically, the operator of machine210may survey the two new anchor points, which create the new location for anchor line670that defines the ends of sub-zones650and660. Based on both the determination of the new position of anchor line670and the unchanged location of shovel-side pole620, the new boundary of the static isolation sub-zone650may be determined by the computer on- or off-board of machine210. Further, or in the alternative, the new location of anchor line670and the new location of machine210may be used to determine the new boundary of the dynamic isolation sub-zone660. By this process, the boundary of static isolation sub-zone650and the boundary of dynamic isolation sub-zone660may be automatically generated or redetermined, such as by the use of the above-discussed algorithm, while the boundary of static first isolation zone610may remain the same and may not need to be redetermined. Upon subsequent movement of machine210to an adjacent position, the boundaries of first zone610and static sub-zone650may not change and may not need to be redetermined, but only the boundary of dynamic sub-zone660may change and may need to be redetermined.

Aspects of the disclosure, such as the above-discussed determination of boundaries of isolation zone630and/or sub-zones650or660, may be stored on a tangible, computer-readable storage medium. The medium may store a program that when executed by a processor of a computer, such as a computer on- or off-board of machine210, manages locations of cable400between or among movements of machine210.