Systems, methods and apparatuses for controlling work machine to avoid overhead power line

Abstract

Preventing a work machine 100 from contacting overhead power lines 109 using sensors 120 to determine if the magnitude or strength of the electric field output by the overhead power line exceeds a pre

Description

The present disclosure pertains to systems, methods, and apparatuses for controlling a work machine to avoid an overhead power line or overhead power lines. Background Work machines, such as excavators, may have extensions, arms, or the like that may reach the height of overhead power lines. Hence, a risk exists of the extensions, arms, or the like of the work machine striking the overhead power line. Thus, operation of a work machine in the vicinity of an overhead power line can pose dangerous risk to the operator of the work machine, the work machine, and the area surrounding the work machine. U.S. Patent No. 11,313,106 (“the ‘106 patent”) describes an electrical protection apparatus to protect mobile machinery operating near electrical conductors such as buried electrical cables or overhead power lines. According to the ‘106 patent, an indicator indicates when a signal indicative of electromagnetic induction from electricity of the electrical conductor reaches an alarm condition, where such indicator may be a graded indication of the alarm condition. The ‘ 106 patent also describes monitoring the signal and i) recording a log of movement commands executed by the control system; ii) if the signal reaches a predetermined threshold, overriding the control system so that the portion of the machinery is only maneuverable to reduce the signal below the predetermined threshold; iii) if the signal exceeds the predetermined threshold, overriding the control system and execute the most recent movement commands in reverse to automatically maneuver the portion of the machinery away from the conductor; and iv) if the signal reaches and / or exceeds the predetermined threshold, activate the indicator. However, the electrical protection apparatus to protect mobile machinery according to the ‘106 patent may be subject to hysteresis upon the signal reaching the predetermined threshold. Summary An aspect of the present disclosure a method or system for controlling a work machine relative to an overhead power line can comprise: with the work machine performing machine movement relative to the overhead power line, receiving, from each of one or more electric field sensors, signaling indicative of a magnitude of an electric field output by the overhead power line; determining, using a processor, whether the magnitude of the electric field reaches or exceeds a first predetermined magnitude threshold; outputting control signaling, using the processor, to stop the machine movement responsive to the magnitude of the electric field reaching or exceeding the first predetermined magnitude threshold; and performing in reverse, using the processor, some or all of the machine movement from the stopped position of the work machine until signaling from all of the one or more electric field sensors indicates that the magnitude of the electric field is at or below a third predetermined magnitude threshold less than the first predetermined magnitude threshold for a predetermined amount of time. According to another aspect of the present disclosure, a system or method for determining preventing a work machine from contacting an overhead power line at a worksite, the work machine having a lower traveling body and an upper body operatively coupled to the lower traveling body, and a front linkage having a first end operatively coupled to the upper body, wherein the front linkage is selectively controllable to be at heights entirely above the upper body, can comprise: a plurality of electric field sensors each to measure electric field around the work machine; a non-transitory computer-readable storage medium; and circuitry operatively coupled with the non-transitory computer-readable storage medium and configured to: with the work machine performing machine movement relative to the overhead power line, continuously determine, in real-time, based on outputs from the plurality of electric field sensors, whether a strength of the electric field around the work machine exceeds a first predetermined strength threshold, responsive to one or more of the outputs from the plurality of electric field sensors indicating that the strength of the electric field has reached the first predetermined strength threshold, stop the machine movement of the work machine, and perform in reverse the machine movement from the stopped position until the strength of the electric field sensed by all of the electric field sensors is at or below a third predetermined strength threshold less than the first predetermined strength threshold. Brief Description of Drawings FIG. 1 shows an exemplary work machine, according to one or more embodiments of the present disclosure, in the vicinity of an overhead power line system. FIG. 2 is a diagram of an example environment in which systems, methods, and / or apparatuses may be implemented, in accordance with one or more embodiments of the present disclosure. FIG. 3 is a diagram of example components of a device or system according to one or more embodiments of the present disclosure. FIG. 4 is a chart showing exemplary minimum clearance distances relative to power line voltage, according to one or more embodiments of the present disclosure. FIG. 5 shows an example of a table of stored historical machine movement data according to one or more embodiments of the present disclosure. FIGs. 6-8 show exemplary operator displays according to one or more embodiments of the present disclosure. FIG. 9 is a flow chart of a method according to one or more embodiments of the present disclosure. FIG. 10 is a graph showing exemplary work machine control according to one or more embodiments of the present disclosure. FIG. 11 is a graph showing exemplary work machine control according to one or more embodiments of the present disclosure. Detailed Description Embodiments of the present disclosure may be regarded as pertaining to systems, methods, and apparatuses for controlling a work machine relative to a power line, particularly an overhead power line. An overhead power line can be regarded as a structure used in electric power transmission and distribution to transmit electrical energy along large distances. In general, the overhead power line structure can be comprised of one or more electrical conductors (commonly multiples of three) suspended by towers or poles. FIG. 1 shows an exemplary work machine 100 according to one or more embodiments of the present disclosure, in the vicinity of an overhead power line system 109. The work machine 100 in FIG. 1 is an excavator, though embodiments of the present disclosure are not limited to either the particular excavator shown or excavators in general. For example, the work machine may be a haul truck, a dozer, a loader, a backhoe, a motor grader, a wheel tractor scraper, or some other earth moving machine. The work machine 100 can include a frame 102 supporting an engine 104. The frame 102, which can include an operator cab, can be supported by ground-engaging elements 106 (e.g., shown as tracks in FIG. 1). Although the ground-engaging elements 106 are shown as being tracks in FIG. 1, the ground-engaging elements 106 may be any suitable ground-engaging elements (e.g., wheels, among other examples). The ground-engagement elements 106 can be regarded as a lower traveling body, and the frame 102 can be regarded as an upper body. According to one or more embodiments, the frame 102 can be rotated relative to the ground-engaging elements 106 about a connection interface between the frame 102 and the ground-engaging elements 106. As such, the upper body may be regarded as an upper swiveling body, and such upper swiveling body can be regarded as being operatively coupled to the lower traveling body. The work machine 100 can include a work tool assembly 108, which may be regarded as an extension, an arm, a front linkage, or the like, such as the work tool assembly 108 shown in FIG. 1 that can include a boom 110, a stick 112, and a bucket 114 controllable, for instance, via hydraulic lines 116 of a hydraulic system 118 of the work machine 100). According to one or more embodiments, the work tool assembly 108 may be regarded as a front linkage. A first end of the work tool assembly 108, particularly a lower end of the boom 110, can be rotatably operatively coupled to the frame 102, such as shown in FIG. 1. Movement of the work tool assembly 108 about the interface with the frame 102 can cause certain portions of the work tool assembly 108 to be at heights entirely above the frame 102, particularly to at or above an overhead power line of the overhead power line system 109 or some other overhead hazard that carries electricity or is otherwise electrified or has the potential of being electrified. Such portions of the work tool assembly 108 (e.g., the bucket 114, the stick 112, the other end of the boom 110) can be regarded as portions that are prone to hitting or potentially hitting an overhead power line of the overhead power line system 109. Although the work tool assembly 108 is shown in FIG. 1 as including the boom 110, the stick 112, and the bucket 114 as the work tool or implement, the work tool assembly 108 according to embodiments of the present disclosure may include any suitable component as a work tool or implement (e.g., a hydraulic thumb, an auger, a hammer, a compactor, a shear attachment, and / or a rock saw, among other examples) or as part of the work tool assembly 108 (e.g., additional or alternative components, such as a foreboom, an offset boom, a quick coupler, a coupler, tilt rotator, etc.). The work tool assembly 108 may be used to perform work operations, such as operations at a worksite (e.g., shown as a worksite including the overhead power line system 109 in FIG. 1). The work machine 100, according to one or more embodiments of the present disclosure, can include one or more electric field sensing devices 120, which may also be referred to herein singularly as electric field sensing device 120; one or more position and / or movement sensing devices 122; a controller 124 (e.g., an electronic control module ECM, among other examples); and a power source 126 (e.g., a battery, among other examples). The electric field sensing device 120 may be referred to or regarded as an electric field sensor or sensing circuitry. Likewise, the position and / or movement sensing device 122 may be regarded as a position and / or movement sensor or sensing circuitry. The power source 126 can be operatively coupled to electric field sensing device(s) 120, the position and / or movement sensing device 122, and / or the controller 124. In this way, the power source 126 may provide electrical power to each electric field sensing device 120, each position and / or movement sensing device 122, and / or the controller 124. Referring now to FIG. 2, FIG. 2 is a diagram of an example environment 200 m which systems, methods, and / or apparatuses in accordance with one or more embodiments of the present disclosure may be implemented. In some cases, the environment 200 may be regarded as a system. The environment 200 can include at least one electric field sensing device 202 (e.g., which may correspond to the electric field sensing device 120), at least one position and / or movement sensing device 204, a controller 206 (e.g., which may correspond to the controller 124), a power source 208 (e.g., which may correspond to the power source 126), and a network 210. In some implementations, the electric field sensing device 202 may be separate from the position and / or movement sensing device 204 and / or the controller 206. In some other implementations, the position and / or movement sensing device 204 and / or the controller 206 can be integrated into the electric field sensing device 202 enabling the electric field sensing device 202. The electric field sensing device 202 may be any suitable electric field sensing device. As an example, the electric field sensing device 202 may be a voltage proximity alarm (e.g., a high-voltage proximity alarm), an electric field meter, a capacitive proximity sensors, an electric field imaging sensor (e.g., associated with an electric field imaging sensor system), an electric field strength detector, a dielectric spectroscopy sensor, an electric field antenna, an electric field strength monitor, and / or an electric field probe, among other examples. The power source 208 may be an electric power source, such as a battery, among other examples. The power source 208 can provide electric power (e.g., via an electric power output) to the electric field sensing device 202, the position and / or movement sensing device 204, and / or the controller 206 (e.g., the power source 208 may provide a stable and controlled electrical voltage to the electric field sensing device 202, the position and / or movement sensing device 204, and / or the controller 206). In some implementations, the power source 208 may be a battery equipped on a work machine (e.g., the work machine 100 of FIG. 1) and / or an external power source, such as an external generator, powerline, and / or power grid, among other examples, electrically coupled to the machine (e.g., the work machine 100 may be a tethered machine). The electric power may be distributed through a circuit or electric system to provide the electrical power output to the electric field sensing device 202, the position and / or movement sensing device 204, and / or the controller 206 (e.g., the circuit or electric system may include switches, relays, and / or control circuits, among other examples, to manage a flow of electricity from the power source 208 to the electric field sensing device 202, the position and / or movement sensing device 204, and / or the controller 206). The controller 206 may be communicatively coupled to the electric field sensing device 202 and / or the position and / or movement sensing device 204 via a wired or wireless network, such as the network 210. The electric field sensing device 202 may also detect and / or measure electric field strength of the overhead power line system 109, including when the electric field sensing device 202 is moving vis-a-vis machine movement of the work machine 100. The network 210 may include one or more wired and / or wireless networks. For example, the network 210 may include a wireless wide area network (e.g., a cellular network or a public land mobile network), a local area network (e.g., a wired local area network or a wireless local area network (WLAN), such as a Wi-Fi network), a personal area network (e.g., a Bluetooth network), a near-field communication network, a telephone network, a private network, the Internet, and / or a combination of these or other types of networks. The network 210 can enable communication among the devices of the environment 200, such as those shown in FIG. 1. The number and arrangement of components and network shown in FIG. 2 are provided as an example. In practice, there may be additional components and / or networks, fewer devices and / or networks, different devices and / or networks, or differently arranged devices and / or networks than those shown in FIG. 2. Furthermore, two or more of the components shown in FIG. 2 may be implemented within a single device, or a single component shown in FIG. 2 may be implemented as multiple, distributed devices. Additionally, or alternatively, a set of devices (e.g., one or more devices) of the environment 200 may perform one or more functions described as being performed by another set of devices of environment 200. FIG. 3 is a diagram of example components of a device (or apparatus) or system 300 according to one or more embodiments of the present disclosure. The device or system 300 may correspond to a controller (e.g., the controller 124 and / or the controller 206), at the very least. As shown in FIG. 3, the device or system 300 may include, for example, a bus 310, a processor 320, a memory 330, an input component 340, an output component 350, and / or a communication component 360. The bus 310 may include one or more components that enable wired and / or wireless communication among the components of the device or system 300. The bus 310 may couple together two or more components of FIG. 3, such as via operative coupling, communicative coupling, electronic coupling, and / or electric coupling. For example, the bus 310 may include an electrical connection (e.g., a wire, a trace, and / or a lead) and / or a wireless bus. The processor 320, which may be implemented in the controller (e.g., the controller 124 and / or the controller 206) may include a central processing unit, a graphics processing unit, a microprocessor, a controller, a microcontroller, a digital signal processor, a field-programmable gate array, an application-specific integrated circuit, and / or another type of processing component. The processor 320 may be implemented in hardware, firmware, or a combination of hardware and software. In some implementations, the processor 320 may include one or more processors capable of being programmed to perform one or more operations or processes described elsewhere herein. The memory 330 may include volatile and / or nonvolatile memory. For example, the memory 330 may include random access memory (RAM), read only memory (ROM), a hard disk drive, and / or another type of memory (e.g., a flash memory, a magnetic memory, and / or an optical memory). The memory 330 may include internal memory (e.g., RAM, ROM, or a hard disk drive) and / or removable memory (e.g., removable via a universal serial bus connection). The memory 330 may be a non-transitory computer-readable medium. The memory 330 may store information, one or more instructions, and / or software (e.g., one or more software applications) related to the operation of the device 300. In some implementations, the memory 330 may include one or more memories that are coupled (e.g., communicatively coupled) to one or more processors (e.g., processor 320), such as via the bus 310. Communicative coupling between the processor 320 and the memory 330 may enable the processor 320 to read and / or process information stored in the memory 330 and / or to store information in the memory 330. The input component 340 may enable the device or system 300 to receive input, such as user input and / or sensed input. For example, the input component 340 may include a touch screen, a keyboard, a keypad, a mouse, a button, a microphone, a switch, a sensor, a global positioning system sensor, an accelerometer, a gyroscope, and / or an actuator. The output component 350 may enable the device or system 300 to provide output, such as via a display, a speaker, and / or a lightemitting diode. The communication component 360 may enable the device or system 300 to communicate with other devices via a wired connection and / or a wireless connection. For example, the communication component 360 may include a receiver, a transmitter, a transceiver, a modem, a network interface card, and / or an antenna. The device or system 300 may perform one or more operations or processes described herein. For example, a non-transitory computer-readable medium (e g., memory 330) may store a set of instructions (e.g., one or more instructions or code) for execution by the processor 320. The processor 320 may execute the set of instructions to perform one or more operations or processes described herein. In some implementations, execution of the set of instructions, by one or more processors 320, causes the one or more processors 320 and / or the device or system 300 to perform one or more operations or processes described herein. In some implementations, hardwired circuitry may be used instead of or in combination with the instructions to perform one or more operations or processes described herein. Additionally, or alternatively, the processor 320 may be configured to perform one or more operations or processes described herein. Thus, implementations described herein are not limited to any specific combination of hardware circuitry and software. The number and arrangement of components shown in FIG. 3 are provided as an example. The device or system 300 may include additional components, fewer components, different components, or differently arranged components than those shown in FIG. 3. Additionally, or alternatively, a set of components (e.g., one or more components) of the device or system 300 may perform one or more functions described as being performed by another set of components of the device or system 300. Referring again to FIG. 1, one or more electric field sensing devices 120 can be mounted or otherwise provided at various locations of the work machine 100, particularly those that may be prone to hitting or potentially hitting an overhead power line of the overhead power line system 109. As examples, as noted above, portions of the work tool assembly 108 that are controllable to reach heights entirely above the frame 102, particularly to at or above the height of an overhead power line of the overhead power line system 109 or some other overhead hazard that carries electricity or is otherwise electrified or has the potential of being electrified, can be regarded as portions that are prone to hitting or potentially hitting an overhead power line of the overhead power line system 109. The one or more position and / or movement sensing devices 122, each of which can be an inertial measurement unit (IMU) or the like, can also be mounted or otherwise provided at various locations of the work machine 100, particularly those that may be prone to hitting or potentially hitting an overhead power line of the overhead power line system 109. According to one or more embodiments of the present disclosure, the one or more position and / or movement sensing devices 122 may be respectively provided in proximity to the one or more electric field sensing devices 120. Optionally, the one or more position and / or movement sensing devices 120 may be provided at least in one-to-one correspondence with respective ones of the one or more electric field sensing devices 120. Hence the readings of the position and / or movement sensing device 122, which can include velocity or speed of machine movement of the corresponding portion of the work machine 100, can be associated with the electric field magnitude or strength readings of the electric field sensing device 120. Optionally, the one or more position and / or movement sensing devices 122 may be integral with the one or more electric field sensing devices 120. Alternatively, the one or more position and / or movement sensing devices 122 may be separate from the one or more electric field sensing devices 120 with or without direct electrical connection between the two components. Each of one or more electric field sensing devices 120, which may be of 1-axis version having primary sensitivity in the normal direction or of 3-axis version having primary sensitivity in all three directions, can detect electric field generation by the overhead power line system 109, the strength of which may be regarded as electric field magnitude of the overhead power line system 109 (e.g., one or more power lines thereof). In that various portions of the work machine 100 such as those discussed above (including the work machine 100 as a whole) can be controlled to move, each electric field sensing device 120 may be used to detect changes in electric field strength surrounding the electric field sensing device 120, such as changes due to machine movement relative to the overhead power line system 109 and / or changes in the strength of the electric field generated by the overhead power line system 109 (e.g., due to a power surge). Electric field strength or magnitude sensed by each electric field sensing device 120 may be indicative of proximity to the overhead power line system 109 (e.g., one or more power lines thereof), particularly proximity of the specific component at which the electric field sensing device 120 is provided to the overhead power line system 109, as discussed above. Data from each electric field sensing device 120 can be used by the controller 124, for instance, to calculate magnitude or strength of the electric field output by the overhead power line system 109 and / or to calculate direction of the electric field output by the overhead power line system 109. Incidentally, the direction of the electric field, as sensed by each of the electric field sensing device 120 and determined by the controller 124, can be regarded as being in a direction that can oscillate toward or away from the overhead power line system 109, where such direction may be regarded as an estimate of the actual direction. According to one or more embodiments, the electric field sensing device 120 may be the sole electric field sensing on the work machine 100 or associated with a particular point or location of the work machine 100. In this regard, select locations on the work machine 100 at which the electric field strength is computed can be void of electric field sensors, which can mean the controller 124 can determine the electric field strength or magnitude at points along the work machine 100 that are void of the electric field sensing devices 120 but based on data from one or more of the electric field sensing devices 120. Proximity or clearance from the overhead power line system 109, according to one or more embodiments of the present disclosure, may be characterized into at least safe and unsafe distances. For instance, FIG. 4 is a chart showing exemplary minimum clearance distances away from a power line at various power line voltages according to one or more embodiments of the present disclosure. Such minimum clearance distances, according to one or more embodiments of the present disclosure, may be based on certain governmental requirements, such as requirements from the Occupational Safety and Health Administration (OSHA). Notably, the minimum clearance distance may be set or defined based on the power line voltage (typically in kV). In general, FIG. 4 shows exemplary minimum clearance distances for power line voltages from less than 50 kV (e.g., 10 ft. / 3.0 m) to 750-1,000 kV (e.g., 45 ft. / l3.7 m). According to one or more embodiments, exceeding the minimum clearance, i.e., within the minimum clearance distance away from the overhead power line system 109, may be regarded as an unsafe distance away from the overhead power line system 109. Electric field strength or magnitude can be regarded as being in correlation with the power line voltage output by the overhead power line system 109 and the distance away from the overhead power line system 109. In general, the closer to the overhead power line system 109 the greater its electric field strength. Accordingly, electric field strength can indicate proximity to the overhead power line system 109. As noted above, each of the one or more electric field sensing devices 120 can sense electric field strength or magnitude. Accordingly, measured or sensed electric field strength by the electric field sensing device 120 can indicate proximity of the portion of the work machine 100 associated with the electric field sensing device 120 relative to the overhead power line system 109. According to one or more embodiments, one or more predetermined strength thresholds may be set, for instance, by or using the controller 124, for comparison against the magnitude of electric field(s) from the overhead power line system 109 sensed by the electric field sensing device 120. The predetermined strength threshold, according to one or more embodiments, can be based on a predetermined distance, proximity, or clearance away from the overhead power line system 109. As an example, such predetermined strength threshold can be based on the electric field strength corresponding to an unsafe distance to the overhead power line system 109, for instance, corresponding to a minimum clearance away from the particular overhead power line system 109 such as discussed above. Such exemplary predetermined strength threshold can be regarded as a first predetermined strength threshold. As alluded to above, the work machine 100, according to one or more embodiments of the present disclosure, can be controlled, using or under control of the controller 124, to move forward or in reverse according to a direction or orientation of the ground-engaging elements 106; the frame 102 can be controlled, using or under control of the controller 124, to swivel or rotate in an overhead plan view of the work machine 100 based on opposite movement of opposite groundengaging elements 106 and / or relative to the ground-engaging elements 106; and the work tool assembly 108 can be controlled, using or under control of the controller 124, to rotate relative to the frame 102. Further, in that the work tool assembly 108 can be segmented into jointed movable components (e.g., the boom 110, the stick 112, and the bucket 114), one or more portions of the work tool assembly 108 may be individually movable using or under control of the controller 124. The work machine 100 can be controlled according to only one of the foregoing occurring at one time (i.e., only one being performed at the same time) or according to some of the foregoing occurring at one time (e.g., two or more of the foregoing occurring at the same time). Thus, the work machine 100 can be regarded as being able to be controlled to move according to the foregoing three machine movement axes or vectors, individually or in combination and at the same time. And movement of the work machine 100 forward or backward via control of the groundengaging elements 106 along a surface of the worksite may cause the work machine 100 as a whole to rise, to fall, or to remain at the same height, depending upon the contour of the surface and movement of the work machine 100 about the surface. Movement of the work machine 100 in terms of rising or falling as the work machine 100 traverses the surface may be regarded as movement in a fourth axis or vector. Incidentally, the foregoing movements of the work machine 100 and / or portions thereof may be regarded as kinematic variables. Hence, according to one or more embodiments, machine movement may be regarded as involving one, some, or all of the foregoing four kinematic variables of the work machine 100 and / or one or more additional kinematic variables of the work machine 100, for instance, depending upon the type of work machine 100, the type of work assembly or linkage 108, etc. Incidentally, according to one or more embodiments of the present disclosure, control of the different machine movements can be such that the speed or velocity of one or some (including all) of such machine movements is different from the speed or velocity of at least other of such machine movements, whether such machine movements occur individually or at the same time (e.g., movement of the ground-engaging elements 106 may be slower than the rotation of the work tool assembly 108 relative to the frame 102). The one or more electric field sensing devices 120 may send, and the controller 124 may receive, electric field information (e.g., one or more electric field parameters such as sensed e-field strength or magnitude and / or direction) related to the electric field generated by the overhead power line system 109. Thus, the electric field sensing device 120 can send, and the controller 124 can receive, the output signal generated by each electric field sensing device 120. Such output signaling can include or indicate voltage variations, changes in capacitance, and / or one or more other measurable parameters that reflect detected electric field strength. The controller 124 can process the information, as described in more detail elsewhere herein. Such outputting and processing may be regarded as being performed in real time. In that the work machine 100 (as a whole and / or one or more different portions thereof) can be controlled to move (e.g., in one or more dimensions or axes) relative to the overhead power line system 109, m that certain portions of the work machine 100 may be at risk of being controlled to come into contact with the overhead power line system 109, and in that such portions of the work machine 100 may have associated therewith one or more electric field sensing devices 120, the controller 124 can track electric field strength or magnitude values sensed by the electric field sensing device(s) 120 as the work machine 100 moves relative to the overhead power line system 109. And in the case of the work machine 100 moving relative to the overhead power line system 109, the controller 124 can determine direction of the electric field relative to the moving portion(s) of the work machine 100. Here, according to one or more embodiments, the controller 124 can calculate the spatial gradient of the electric field magnitude and / or the direction in which the electric field is changing the most to determine the direction of the electric field and hence the direction toward the overhead power line system 109. The controller 124 can determine, for instance, continuously and in real-time, whether the electric field strength of the overhead power line system 109, as sensed by each of the one or more electric field sensing devices 120, reaches one or more of the predetermined strength thresholds. Optionally, the controller 124 can take into consideration a determined direction of the electric field to determine or confirm whether the work machine 100 as a whole or portion thereof is moving toward the overhead power line system 109 when the electric field strength sensed by one or more of the electric field sensing devices 120 at least reaches one of the one or more predetermined strength thresholds. As noted above, sensed electric field strength can be an indicator of proximity or distance of the work machine 100 as a whole or portion thereof away from the overhead power line system 109. Under a condition where the electric field strength sensed by one or more of the electric field sensing devices 120 at least reaches one of the one or more predetermined strength thresholds, the controller 124 may take further action in response to reaching such condition. According to one or more embodiments, the condition can be met when any one of the electric field sensing devices 120 senses electric field reaching one of the one or more predetermined strength thresholds. Further, optionally, the condition can be met when any one of the electric field sensing devices 120 senses electric field reaching one of the one or more predetermined strength thresholds being at or above the one or more predetermined strength thresholds for a predetermined period of time (e.g., 1 to 3 seconds). Alternatively, the condition can be met when any two or more of the electric field sensed by the electric field sensing devices 120 reaches one of the one or more predetermined strength thresholds, for instance, as a double check or confirmation of the strength of the sensed electric field relative to the location of the work machine 100. Optionally, the controller 124 can determine a direction of the sensed electric field and as noted above, can take such determined direction into account to determine or confirm whether the work machine 100 as a whole and / or portion thereof is moving toward the overhead power line system 109 and may risk contacting the overhead power line system 109. According to one or more embodiments, multiple predetermined strength thresholds can be implemented. As an example, as noted above, the first predetermined strength threshold can be set to an electric field strength value corresponding to the work machine 100 being at the predetermined minimum clearance distance from the overhead power line system 109, and a second predetermined strength threshold can be set to an electric field strength value corresponding to a situation where no portion of the work machine 100 is within the predetermined minimum clearance distance from the overhead power line system 109 (i.e., not unsafely close to). The second predetermined strength threshold can be a percentage of the first predetermined strength threshold (e.g., 70%-80%). One or more additional predetermined strength thresholds can be set for a situation or situations where the work machine 100 is located outside of the predetermined minimum clearance distance from the overhead power line system 109. Such one or more additional predetermined strength thresholds may also be a percentage of the first predetermined strength threshold. Reaching the second predetermined strength threshold can cause the controller 124 to output one or more alerts 354 or the like to an operator that the work machine 100 has been determined to be close enough to the overhead power line system 109 that the controller 124 may be called upon to further control the work machine 100 so the work machine 100 does not come into contact with the overhead power line system 109 should the first predetermined strength threshold be reached. The alert(s) 354 or the like to the operator can be output via the output component 350 of the work machine 100. FIG. 7 shows exemplary alerts 354, according to one or more embodiments, on a display 352 of the output component 350, which may be regarded as an operator display. For instance, reaching the second predetermined strength condition can cause the display 352 to transition from the images shown in FIG. 6 to the images shown in FIG. 7. The right side of the display 352 of FIG. 7 also shows the direction of the electric field relative to the work machine 100, for instance, as part of one of the alerts 354. Such direction of the electric field on the display 352, which may be shown at all times and not necessarily just as part of one of the alerts 354, may be regarded as an electric field compass. Optionally, according to one or more embodiments, reaching the second predetermined strength threshold can cause the controller 124 to begin recording machine movement of the work machine 100, for instance, machine movement associated with movement of the one or more electric field sensors 120 of the work machine 100 relative to the overhead power line system 109. Alternatively, according to one or more embodiments of the present disclosure, for machine movement of the work machine 100 toward the overhead power line system 109, only the first predetermined strength threshold may be implemented and not the second predetermined strength threshold. Machine movement data can be recorded and stored in the memory 330 and accessed by the processor 302 of the controller 124 for further movement control of the work machine 100 should the first predetermined threshold also be reached. Alternatively, machine movement can be tracked prior to (and after) reaching the second predetermined strength threshold and stored in the memory 330 for further movement control of the work machine 100 should the first predetermined threshold also be reached. Such recorded machine movement data may be regarded as historical machine movement data. FIG. 5 shows an example of a table or database of stored historical machine movement data according to one or more embodiments of the present disclosure. The table of FIG. 5 may be regarded as a simplified view of stored historical machine movement data to illustrate the aspect of machine movement reversal, which is discussed in more detail below. The time t may be regarded as the current time, while the times t-1..4-n can represent previous or historical times associated with movement of the work machine 100. More specifically, the time can be correlated with machine movement, thus keeping a history of machine movements for the work machine 100 as the work machine 100 moves relative to the overhead power line system 109. The table, such as shown in FIG. 5, may also have an electric field value as sensed by the one or more electric field sensing devices 120 in correspondence with the time t and the machine movement. The electric field values in the table of FIG. 5, according to one or more embodiments of the present disclosure, can be regarded in terms of a percentage of the first predetermined strength threshold, i.e., electric field strength value corresponding to the work machine 100 at the predetermined minimum clearance distance from the overhead power line system 109. Thus, in a sense, the percentage of the electric field strength can be regarded as proximity of the work machine 100 to the overhead power line system 109. The electric field values from each of the electric field sensing devices 120 can be stored per unit of time. Machine movement per increment of time can be in terms of one or a combination of the work machine 100 moving forward or in reverse according to a direction or orientation of the ground-engaging elements 106, the frame 102 (and optionally the work tool assembly 108) rotating in an overhead plan view of the work machine 100 based on opposite movement of opposite ground-engaging elements 106, the frame (and the work tool assembly 108) swiveling relative to the ground-engaging elements 106 in the overhead plan view of the work machine 100, and / or rotation or pivoting of one or more portions of the work tool assembly 108. Thus, machine movement column in FIG. 5 can include only one of the foregoing machine movements or a combination of two or more of the foregoing machine movements. The foregoing machine movements can result in corresponding movement of the associated electric field sensing device(s) 120. As but one example, the work machine 100 can be moving straight toward the overhead power line system 109. As the work machine 100 approaches the overhead power line system 109 at some point one or more of the electric field sensing devices 120 can sense the electric field generated by the overhead power line system 109. Here, movement of the work machine 100 forward and amount of movement can be regarded as the machine movement per unit of time. Thus, the controller 124 can receive feedback from the work machine 100 indicating the machine movement and record such movement in the memory 330, such as shown in the table of FIG. 5. The electric field of the overhead power line system 109, as sensed by the electric field sensing device(s) 120, can be recorded in the memory 300 in correspondence with the time and the particular machine movement, such as shown in the table of FIG. 5. The machine movement information and the electric field values can be recorded prior to reaching the first predetermined strength threshold, such as described above. Under a condition where the electric field strength sensed by one or more of the electric field sensing devices 120 reaches the first predetermined strength threshold, the controller 124 can output control signaling to stop some or all of the machine movement of the work machine 100. At the very least the controller 124 can output control signaling to stop machine movement associated with the electric field sensing device(s) 120 that have detected electric field strength reaching the first predetermined strength threshold. According to one or more embodiments, the controller 124 can stop all machine movement in response to determining that the detected electric field strength from at least one of the electric field sensing devices 120 has reached the first predetermined strength threshold. Optionally, under the condition where the electric field strength sensed by one or more of the electric field sensing devices 120 reaches the first predetermined strength threshold, the controller 124 can set the work machine 100 to a derated performance mode. Such derated performance mode can involve derating outputs for some or all of the machine movement. In general, derating can be regarded as putting one or more limitations on machine movement of the work machine 100 (e.g., limit or cap on velocity of movement for the work machine 100 and / or the work assembly 108, range or rotation of the work assembly 108, range of rotation or swivel of the frame 102, etc.). The work machine 100 can be placed in derated performance mode upon reaching the first predetermined strength threshold or upon stopping of the work machine 100 as a whole and / or portions thereof, to the extent that there is a lag between the two. Reaching the first predetermined strength threshold may also cause the controller 124 to output one or more warnings 356 or the like (e.g., audio, visual, and / or haptic) to an operator that the work machine 100 has been determined to be an unsafe distance away from the overhead power line system 109 and the controller 124 has therefore stopped some or all of the machine movement of the work machine 100. The warning(s) 356 or the like to the operator can be output via the output component 350 of the work machine 100. FIG. 8 shows exemplary warnings 356, according to one or more embodiments, on the display 352 of the output component 350. For instance, reaching the first predetermined strength condition can cause the display 352 to transition from the images shown in FIG. 7 to the images shown in FIG. 8. The right side of the display 352 of FIG. 8 also shows the direction of the electric field relative to the work machine 100, for instance, as part of one of the warnings 356. Such direction of the electric field on the display 352 may be shown at all times and not necessarily just as part of one of the warnings 356. Optionally, the controller 124 can output information regarding proximity of the work machine 100 relative to the overhead power line system 109 based on reaching the first predetermine strength threshold to a back office, fleet management system, and / or one or more other work machines. Such information may be indicative of or otherwise used to define a safe boundary or electric-fence a predetermined safe distance away from the overhead power line system 109, for instance, using location information (e.g., from a GPS system onboard the work machine 100) to identify the location of the work machine 100 upon reaching the first predetermined strength threshold. According to one or more embodiments, a site map of the worksite may be updated with the specific location of the unsafe positioning, for instance, for later use by the work machine 100 or one or more other work machines at the worksite. Once machine movement of the work machine 100 has stopped, the machine movements up to the point of the work machine 100 stopping can be performed in reverse to move the work machine 100 away from the overhead power line system 109. Here, the controller 124 can access the machine movements saved in the memory 330 and control the work machine 100 to perform the machine movements in reverse order. Optionally, the operator may be provided with the ability to override reversal of some or all of the machine movements performed in reverse, for instance, if such machine movements would also be unsafe for the work machine 100. According to one or more embodiments of the present disclosure, such override option may not, however, allow the operator to control the work machine 100 to move closer to the overhead power line system 109, for instance, than as the work machine 100 was at the initial stop position. As one example, the history of machine movements can be performed in reverse until the electric field value sensed by each of the electric field sensing devices 120 is below a predetermined strength threshold. Optionally, the history of machine movements can be performed in reverse until the electric field value sensed by each of the electric field sensing devices 120 is below the predetermined strength threshold for a predetermined amount of time (e.g., 2 to 5 seconds). Though the machine movements were performed at certain speeds in the forward direction, in the reverse direction some or all of the machine movements may be performed at different speeds compared to the forward direction, for instance, at lower speeds. Thus, machine movements associated with all of the electric field sensing devices 120 can be stored in the memory 330 and accessed by the controller 124, even though some of the electric field sensing devices 120 may not have sensed electric field strength above the first predetermined threshold. Such predetermined strength threshold may be the above-discussed second predetermined strength threshold or another predetermined strength threshold, which may be regarded as a third predetermined strength threshold. Like the second predetermined strength threshold, the third predetermined strength threshold may be a percentage of the first predetermined strength threshold (e.g., 75%, 70%. etc.). In general, this predetermined strength threshold may be regarded as corresponding to the work machine 100 being a suitable safe distance away from the overhead power line system 109. Upon or after a predetermined time upon reaching the reaching the predetermined strength threshold corresponding to the work machine 100 being a suitable safe distance away from the overhead power line system 109, the controller 124 can allow the operator to regain control the work machine 100 such that the work machine 100 remains a safe distance away from the overhead power line system 109. Such regaining of control may be regarded as gaining full control of the machine movement of the work machine 100. Optionally, the display 352 can output a safe direction indicator (e.g., an arrow) showing the operator a safe direction away from the overhead power line system 109, such as shown in FIG. 8. Such safe direction indicator may be based on the controller 124 calculating the spatial gradient of the electric field magnitude, where the direction in which the electric field is changing the most can indicate the direction of the overhead power line system 109. Hence, the safe direction indicator can be the opposite of the direction in which the electric field is changing the most. Industrial Applicability As noted above, the present disclosure may be regarded as being directed to systems, methods, and apparatuses for controlling a work machine relative to a power line, particularly an overhead power line. Such control can prevent or minimize certain parts of the work machine from contacting the overhead power line. FIG. 9 is a flow chart of a method 400 according to one or more embodiments of the present disclosure. Some or all of the method 400 can be performed via a non-transitory computer-readable storage medium (or media) having stored thereon instructions that, when executed by one or more processors, such as processor 320, causes the one or more processors to perform some or all of the method 400. According to one or more embodiments, the method 400 may be referred to or characterized as a method for machine control for overhead powerline avoidance. Further, such control may be characterized or referred to as stopping the work machine and moving the work machine away safely from the overhead power line. Additionally or alternatively, the method 400 can be characterized or referred to as methods for machine stop and control to avoid collision with and move away to a safe distance from overhead power lines. Operation 410 of method 400 can involve movement of one or more portions of the work machine 100. Such movement of the work machine 100 can be under control of the operator of the work machine 100 and relative to the overhead power line system 109. The method 400, at optional operation 420, can sense electric field magnitude of the overhead power line system 109 using the one or more electric field sensing device(s) 120 as the work machine 100 performs machine movement relative to the overhead power line system 109. Optional operation 420 can also involve comparing, using the controller 124, for instance, the sensed strength of the electric field with a second predetermined strength threshold. The second predetermined strength threshold can be set to an electric field strength value corresponding to a situation where no portion of the work machine 100 is within the predetermined minimum clearance distance from the overhead power line system 109 (i.e., not unsafely close to). Under a condition where one or more of the electric field sensing devices 120 senses electric field magnitude from the overhead power line system 109 at least reaching the second predetermined strength threshold at operation 420, the method 400, at optional operation 430, can output one or more alerts 354 or the like, such as shown in FIG. 7, to the operator of the work machine 100 indicating that the work machine 100 has been determined to be close enough to the overhead power line system 109 that further machine control may be required so the work machine 100 does not come into contact with the overhead power line system 109 should a first predetermined strength threshold greater than the second predetermined strength threshold be reached. Under the condition where one or more of the electric field sensing devices 120 senses electric field magnitude from the overhead power line system 109 at least reaching the second predetermined strength threshold at operation 420, the method 400, at optional operation 440, can begin recording machine movement of the work machine 100, for instance, machine movement associated with movement of the one or more electric field sensors 120 of the work machine 100 relative to the overhead power line system 109. As noted above, alternatively, can be tracked prior to (and after) reaching the second predetermined strength threshold at 420. Machine movement data can be recorded and stored in the memory 330 and accessed by the processor 302 of the controller 124 for further movement control of the work machine 100 should the first predetermined strength threshold also be reached after reaching the second predetermined strength threshold. The method 400, at operation 450, can determine, using the controller 124, for instance, whether the electric field strength sensed by one or more of the electric field sensing devices 120 reaches a first predetermined strength threshold. The first predetermined strength threshold can, as an example, be set to an electric field strength value corresponding to the work machine 100 being at the predetermined minimum clearance distance from the overhead power line system 109. Under a condition where the electric field strength sensed by one or more of the electric field sensing devices 120 reaches the first predetermined strength threshold, at operation 460 the method 400 can involve stopping some or all of the machine movement of the work machine 100. As an example, according to one or more embodiments, at the very least the controller 124 can output control signaling to stop machine movement associated with the electric field sensing device(s) 120 that have detected electric field strength reaching the first predetermined strength threshold. According to one or more embodiments, the controller 124 can stop all machine movement in response to determining that the detected electric field strength from at least one of the electric field sensing devices 120 has reached the first predetermined strength threshold. Reaching the first predetermined strength threshold may also cause the controller 124 to output one or more warnings 356 or the like (e.g., audio, visual, and / or haptic) to the operator that the work machine 100 has been determined to be an unsafe distance away from the overhead power line system 109 and machine movement of the work machine 100 has been stopped, such as shown in FIG. 8. Optionally, information regarding proximity of the work machine 100 relative to the overhead power line system 109 based on reaching the first predetermine strength threshold can be output to a back office, a fleet management system, and / or one or more other work machines. Such information may be indicative of or otherwise used to define a safe boundary or electricfence a predetermined safe distance away from the overhead power line system 109, for instance, using location information (e.g., from a GPS system onboard the work machine 100) to identify the location of the work machine 100 upon reaching the first predetermined strength threshold. At operation 470, the method 400 can optionally involve, under the condition where the electric field strength sensed by one or more of the electric field sensing devices 120 reaches the first predetermined strength threshold, setting the work machine 100 to a derated performance mode. Such derated performance mode can involve derating outputs for some or all of the machine movement. In general, derating can be regarded as putting one or more limitations on machine movement of the work machine 100 (e.g., limit or cap on velocity of movement for the work machine 100 and / or the work assembly 108, range or rotation of the work assembly 108, range of rotation or swivel of the frame 102, etc.). Placing the working machine 100 in the derated mode can avoid jerky motion and sudden movements that could be risky. At operation 480 the method 400 can involve, once machine movement of the work machine 100 has stopped, performing in reverse the machine movements up to the point of the work machine 100 stopping to move the work machine 100 away from the overhead power line system 109. The controller 124 can access the machine movements saved in the memory 330 and control the work machine 100 to perform the machine movements in reverse order. Optionally, the operator may be provided with the ability to override reversal of some or all of the machine movements performed in reverse, for instance, if such machine movements would also be unsafe for the work machine 100. At 490 the method 400 can involve performing in reverse the machine movements until the electric field value sensed by each of the electric field sensing devices 120 is below a predetermined strength threshold. Optionally, the history of machine movements can be performed in reverse until the electric field value sensed by each of the electric field sensing devices 120 is below the predetermined strength threshold for a predetermined amount of time (e.g., 2 to 5 seconds). Such predetermined strength threshold may be the above-discussed second predetermined strength threshold or another predetermined strength threshold, which may be regarded as a third predetermined strength threshold. Like the second predetermined strength threshold, the third predetermined strength threshold may be a percentage of the first predetermined strength threshold (e.g., 75%, 70%. etc.). In general, this predetermined strength threshold may be regarded as corresponding to the work machine 100 being a suitable safe distance away from the overhead power line system 109. By implementing this predetermined strength threshold and the optional time requirement for all sensed electric fields being below this predetermined strength threshold, the method 400 (and corresponding system) can avoid hysteresis due to the work machine 100 crossing reaching and receding from the first predetermined strength threshold. At 500 the method 400 can, upon or after a predetermined time upon reaching the reaching the predetermined strength threshold corresponding to the work machine 100 being a suitable safe distance away from the overhead power line system 109, give the operator control again over the work machine 100. Turning now to FIG. 10 and FIG. 11, these figures show graphs of exemplary work machine control according to one or more embodiments of the present disclosure. FIG. 10 shows individual motion tracking for various portions of the work machine 100, where the x-axis can constitute time and the y-axis can represent machine movement for four different aspects of the work machine 100. Notably, FIG. 10 shows individual machine movement for each of the swing angle (e.g., in degrees), the stick angle (e.g., in degrees), the boom angle (e.g., in degrees), and the track / ground-engaging element motion or overall movement of the work machine 100 (e.g., in inches or millimeters). Here, the vertical block indicates stoppage of the individual components due to electric field sensing devices 120 detecting electric field strength from the overhead power line system 109 reaching the first predetermined threshold, as discussed above. The shaded portion to the left of the vertical block indicates the reverse movement of the individual components such that the work machine 100 is safely far enough away from the overhead power line system 109. FIG. 11 shows the first predetermined strength threshold as the trigger threshold and the reverse threshold as the predetermined strength threshold corresponding to the work machine 100 being a suitable safe distance away from the overhead power line system 109. The x-axis can constitute time and the y-axis can constitute electric field strength or magnitude (e.g., in V / mm). The detected electric field magnitude can increase past the reverse threshold to reach the trigger threshold due to movement of the work machine 100, whereupon the work machine 100 can be controlled to stop, as discussed above. As will be appreciated by one skilled in the art, aspects of the present disclosure may be embodied as a system, method or computer program product. Accordingly, aspects of the present disclosure may take the form of an entirely hardware embodiment, an entirely software embodiment (including firmware, resident software, micro-code, etc.) or an embodiment combining software and hardware aspects that may all generally be referred to herein as a “circuit,” “module” or “system.” Furthermore, aspects of the present disclosure may take the form of a computer program product embodied in one or more computer readable medium(s) having computer readable program code embodied thereon. The functionality of the elements disclosed herein may be implemented using circuitry or processing circuitry which includes general purpose processors, special purpose processors, integrated circuits, ASICs (“Application Specific Integrated Circuits”), conventional circuitry and / or combinations thereof which are configured or programmed to perform the disclosed functionality. Processors are considered processing circuitry or circuitry as they include transistors and other circuitry therein. The processor may be a programmed processor which executes a program stored in a memory. In the disclosure, the circuitry, units, or means are hardware that carry out or are programmed to perform the recited functionality. The hardware may be any hardware disclosed herein or otherwise known which is programmed or configured to carry out the recited functionality. When the hardware is a processor which may be considered a type of circuitry, the circuitry, means, or units are a combination of hardware and software, the software being used to configure the hardware and / or processor. Further, as used herein, the term “circuitry” can refer to any or all of the following: (a) hardware-only circuit implementations (such as implementations in only analog and / or digital circuitry); (b) to combinations of circuits and software (and / or firmware), such as (as applicable): (i) a combination of processor(s) or (ii) portions of processor(s) / software (including digital signal processor(s)), software and memory(ies) that work together to cause an apparatus, such as a mobile phone or server, to perform various functions); and (c) to circuits, such as a microprocessor(s) or a portion of a microprocessor(s), that require software or firmware for operation, even if the software or firmware is not physically present. This definition of “circuitry” can apply to all uses of this term in this application, including in any claims. As a further example, as used in this application, the term “circuitry” can also cover an implementation of merely a processor (or multiple processors) or portion of a processor and its (or their) accompanying software and / or firmware. Use of the terms “data,” “content,” “information” and similar terms may be used interchangeably, according to some example embodiments of the present disclosure, to refer to data capable of being transmitted, received, operated on, and / or stored. The term “network” may refer to a group of interconnected computers or other computing devices. Within a network, these computers or other computing devices may be interconnected directly or indirectly by various means including via one or more switches, routers, gateways, access points or the like. Aspects of the present disclosure have been described above with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the present disclosure. In this regard, the flowchart and block diagrams in the Figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer program products according to various embodiments of the present disclosure. For instance, each block in the flowchart or block diagrams may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). It should also be noted that, in some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams and / or flowchart illustration, and combinations of blocks in the block diagrams and / or flowchart illustration, can be implemented by special purpose hardware-based systems that perform the specified functions or acts, or combinations of special purpose hardware and computer instructions. It also will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general-purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions / acts specified in the flowchart and / or block diagram block or blocks. These computer program instructions may also be stored in a computer readable medium that can direct a computer, other programmable data processing apparatus, or other devices to function in a particular manner, such that the instructions stored in the computer readable medium produce an article of manufacture including instructions which implement the function / act specified in the flowchart and / or block diagram block or blocks. The computer program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other devices to cause a series of operational steps to be performed on the computer, other programmable apparatus or other devices to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide processes for implementing the functions / acts specified in the flowchart and / or block diagram block or blocks. Embodiments of the disclosed subject matter can also be as set forth according to the following parentheticals. (1) A system for determining preventing a work machine from contacting an overhead power line at a worksite, the work machine having a lower traveling body and an upper body operatively coupled to the lower traveling body, and a front linkage having a first end operatively coupled to the upper body, wherein the front linkage is selectively controllable to be at heights entirely above the upper body, the system comprising: a plurality of electric field sensors each to measure electric field around the work machine; a non-transitory computer-readable storage medium; and circuitry operatively coupled with the non-transitory computer-readable storage medium and configured to: with the work machine performing machine movement relative to the overhead power line, continuously determine, in real-time, based on outputs from the plurality of electric field sensors, whether a strength of the electric field around the work machine exceeds a first predetermined strength threshold, responsive to one or more of the outputs from the plurality of electric field sensors indicating that the strength of the electric field has reached the first predetermined strength threshold, stop the machine movement of the work machine, and perform in reverse the machine movement from the stopped position until the strength of the electric field sensed by all of the electric field sensors is at or below a third predetermined strength threshold less than the first predetermined strength threshold. (2) The system according to (1), wherein the circuitry is configured to: with the work machine performing the machine movement relative to the overhead power line, continuously determine, in real-time, based on outputs from the plurality of electric field sensors, whether the strength of the electric field around the work machine exceeds a second predetermined strength threshold less than the first predetermined threshold, and output one or more alerts responsive to strength of the electric field sensed by one or more of the electric field sensors reaching the second predetermined strength threshold. (3) The system according to (1) or (2), wherein the second predetermined strength threshold is 70%-80% of the first predetermined strength threshold, and wherein the machine movement includes movement of the work machine as a whole and / or movement of one or more portions of the work machine relative to the lower traveling body. (4) The system according to any one of (1) to (3), wherein the second predetermined strength threshold is the same as the third predetermined strength threshold. (5) The system according to any one of (1) to (4), wherein the circuitry is configured to: begin recording the machine movement responsive to the strength of the electric field sensed by one or more of the electric field sensors reaching the second predetermined strength threshold. (6) The system according to any one of (1) to (5), wherein the circuitry is configured to: provide the operator full control over the machine movement of the work machine responsive to the strength of the electric field sensed by all of the electric field sensors being at or below the third predetermined strength threshold for a predetermined amount of time. (7) The system according to any one of (1) to (6), wherein the circuitry is configured to: derate the machine movement of the work machine responsive to one or more of the outputs from the plurality of electric field sensors indicating that the strength of the electric field has reached the first predetermined strength threshold. (8) The system according to any one of (1) to (7), wherein some or all of the machine movement performed in reverse is performed at a second speed slower than a first speed at which the machine movement was performed prior to stopping the work machine. (9) A method for controlling a work machine relative to an overhead power line, the method comprising: with the work machine performing machine movement relative to the overhead power line, receiving, from each of one or more electric field sensors, signaling indicative of a magnitude of an electric field output by the overhead power line; determining, using a processor, whether the magnitude of the electric field reaches or exceeds a first predetermined magnitude threshold; outputting control signaling, using the processor, to stop the machine movement responsive to the magnitude of the electric field reaching or exceeding the first predetermined magnitude threshold; and performing in reverse, using the processor, some or all of the machine movement from the stopped position of the work machine until signaling from all of the one or more electric field sensors indicates that the magnitude of the electric field is at or below a third predetermined magnitude threshold less than the first predetermined magnitude threshold for a predetermined amount of time. (10) The method according to (9), further comprising: responsive to the magnitude of the electric field reaching or exceeding the first predetermined magnitude threshold, setting, using a positioning system of the work machine and the processor, a location of the work machine or portion thereof as a position of an electric fence or boundary indicating an unsafe distance away from the overhead power line. (11) The method according to (9) or (10), further comprising: commencing, using the processor, saving of the machine movement in memory of the work machine accessible by or using the processor in correspondence with the magnitude of the electric field for all of the one or more electric field sensors responsive to the magnitude of the electric field sensed by at least one of the one or more of the sensed electric field magnitudes reaching a second predetermined magnitude threshold less than the first predetermined magnitude threshold and greater than the third predetermined magnitude threshold. (12) The method according to any one of (9) to (11), further comprising, during said performing in reverse, performing one or more operator confirmation operations to continue or override the performing of said some or all of the machine movement in reverse. (13) The method according to any one of (9) to (12), further comprising: enabling, using the processor, non-derated control of the machine movement of the work machine for an operator of the work machine responsive to the magnitude of the electric field sensed by all of the one or more electric field sensors being at or below the third predetermined magnitude threshold for the predetermined amount of time. (14) The method according to any one of (9) to (13), further comprising: derating, using the processor, the machine movement responsive to the magnitude of the electric field reaching or exceeding the first predetermined magnitude threshold sensed by any of the one or more electric field sensors. (15) The method according to any one of (9) to (14), wherein some or all of the machine movement performed in reverse is performed at a second speed slower than a first speed at which the machine movement was performed prior to stopping the work machine, and wherein the machine movement includes movement of the work machine as a whole and / or movement of one or more portions of the work machine associated with the one or more electric field sensors. It must be noted that, as used in the specification and the appended claims, the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. That is, unless clearly specified otherwise, as used herein the words “a” and “an” and the like carry the meaning of “one or more.” The use of the term “at least one” followed by a list of one or more items (for example, “at least one of A and B” or one or more of A and B”) is to be construed to mean one item selected from the listed items (A or B) or any combination of two or more of the listed items (A and B; A, A and B; A, B and B), unless otherwise indicated herein or clearly contradicted by context. Similarly, as used herein, the word "or" refers to any possible permutation of a set of items. For example, the phrase "A, B, or C" refers to at least one of A, B, C, or any combination thereof, such as any of A; B; C; A and B; A and C; B and C; A, B, and C; or multiple of any item such as A and A; B, B, and C; A, A, B, C, and C; etc. Additionally, it is to be understood that terms such as “left,” “right,” “top,” “bottom,” “front,” “rear,” “side,” “height,” “length,” “width,” “upper,” “lower,” “interior,” “exterior,” “inner,” “outer,” and the like that may be used herein, merely describe points of reference and do not necessarily limit embodiments of the disclosed subject matter to any particular orientation or configuration. Furthermore, terms such as “first,” “second,” “third,” etc., merely identify one of a number of portions, components, points of reference, operations and / or functions as described herein, and likewise do not necessarily limit embodiments of the disclosed subject matter to any particular configuration or orientation. While aspects of the present disclosure have been particularly shown and described with reference to the embodiments above, it will be understood by those skilled in the art that various additional embodiments may be contemplated by the modification of the disclosed machines, assemblies, systems, and methods without departing from the spirit and scope of what is disclosed. Such embodiments should be understood to fall within the scope of the present disclosure as determined based upon the claims and any equivalents thereof.

Claims

1. A system for determining preventing a work machine from contacting an overhead power line at a worksite, the work machine having a lower traveling body and an upper body operatively coupled to the lower traveling body, and a front linkage having a first end operatively coupled to the upper body, wherein the front linkage is selectively controllable to be at heights entirely above the upper body, the system comprising:a plurality of electric field sensors each to measure electric field around the work machine;a non-transitory computer-readable storage medium; andcircuitry operatively coupled with the non-transitory computer-readable storage medium and configured to:with the work machine performing machine movement relative to the overhead power line, continuously determine, in real-time, based on outputs from the plurality of electric field sensors, whether a strength of the electric field around the work machine exceeds a first predetermined strength threshold,responsive to one or more of the outputs from the plurality of electric field sensors indicating that the strength of the electric field has reached the first predetermined strength threshold, stop the machine movement of the work machine, andperform in reverse the machine movement from the stopped position until the strength of the electric field sensed by all of the electricfield sensors is at or below a third predetermined strength threshold less than the first predetermined strength threshold.

2. The system according to Claim 1, wherein the circuitry is configured to: with the work machine performing the machine movement relative to the overhead power line, continuously determine, in real-time, based on outputs from the plurality of electric field sensors, whether the strength of the electric field around the work machine exceeds a second predetermined strength threshold less than the first predetermined threshold, andoutput one or more alerts responsive to strength of the electric field sensed by one or more of the electric field sensors reaching the second predetermined strength threshold.

3. The system according to Claim 2,wherein the second predetermined strength threshold is 70%-80% of the first predetermined strength threshold, andwherein the machine movement includes movement of the work machine as a whole and / or movement of one or more portions of the work machine relative to the lower traveling body.

4. The system according to Claim 2, wherein the second predetermined strength threshold is the same as the third predetermined strength threshold.

5. The system according to Claim 2, wherein the circuitry is configured to: begin recording the machine movement responsive to the strength of the electric field sensed by one or more of the electric field sensors reaching the second predetermined strength threshold.

6. The system according to Claim 1, wherein the circuitry is configured to: provide the operator full control over the machine movement of the work machine responsive to the strength of the electric field sensed by all of the electric field sensors being at or below the third predetermined strength threshold for a predetermined amount of time.

7. The system according to Claim 1, wherein the circuitry is configured to: derate the machine movement of the work machine responsive to one or more of the outputs from the plurality of electric field sensors indicating that the strength of the electric field has reached the first predetermined strength threshold.

8. The system according to Claim 1, wherein some or all of the machine movement performed in reverse is performed at a second speed slower than a first speed at which the machine movement was performed prior to stopping the work machine.

9. A method for controlling a work machine relative to an overhead power line, the method comprising:with the work machine performing machine movement relative to the overhead power line, receiving, from each of one or more electric field sensors, signaling indicative of a magnitude of an electric field output by the overhead power line;determining, using a processor, whether the magnitude of the electric field reaches or exceeds a first predetermined magnitude threshold;outputting control signaling, using the processor, to stop the machine movement responsive to the magnitude of the electric field reaching or exceeding the first predetermined magnitude threshold; andperforming in reverse, using the processor, some or all of the machine movement from the stopped position of the work machine until signaling from all of the one or more electric field sensors indicates that the magnitude of the electric field is at or below a third predetermined magnitude threshold less than the first predetermined magnitude threshold for a predetermined amount of time.

10. The method according to Claim 9, further comprising:responsive to the magnitude of the electric field reaching or exceeding the first predetermined magnitude threshold, setting, using a positioning system of the work machine and the processor, a location of the work machine or portion thereof as a position of an electric fence or boundary indicating an unsafe distance away from the overhead power line.

11. The method according to Claim 9, further comprising:commencing, using the processor, saving of the machine movement in memory of the work machine accessible by or using the processor in correspondence with the magnitude of the electric field for all of the one or more electric field sensors responsive to the magnitude of the electric field sensed by at least one of the one or more of the sensed electric field magnitudes reaching a second predetermined magnitude threshold less than the first predetermined magnitude threshold and greater than the third predetermined magnitude threshold.

12. The method according to Claim 9, further comprising, during said performing m reverse, performing one or more operator confirmation operations to continue or override the performing of said some or all of the machine movement in reverse.

13. The method according to Claim 9, further comprising:enabling, using the processor, non-derated control of the machine movement of the work machine for an operator of the work machine responsive to the magnitude of the electric field sensed by all of the one or more electric field sensors being at or below the third predetermined magnitude threshold for the predetermined amount of time.

14. The method according to Claim 9, further comprising:derating, using the processor, the machine movement responsive to the magnitude of the electric field reaching or exceeding the first predetermined magnitude threshold sensed by any of the one or more electric field sensors.

515. The method according to Claim 9,wherein some or all of the machine movement performed in reverse is performed at a second speed slower than a first speed at which the machine movement was performed prior to stopping the work machine, and10 wherein the machine movement includes movement of the work machineas a whole and / or movement of one or more portions of the work machine associated with the one or more electric field sensors.

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