Nonconductive wire stringer

Abstract

Systems and methods are described herein for a tension monitoring system for operation using an unmanned aerial vehicle (UAV). The tension monitoring system may include a first connector configured to connect to a first line (e.g., a lead line) and a second connector configured to connect to a second line (e.g., a non-conductive line). The second line may be a non-conductive insulated line that is configured to connect to a UAV. The tension monitoring system may include an adjustable spring system configured to measure a tension between the first line and the second line.

Description

Attorney Docket No.: 106652-00038WO_BEIRD9PCTNONCONDUCTIVE WIRE STRINGERCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to United States Provisional Application Serial No. 63 / 743,969, filed January 10, 2025, the contents of which are incorporated herein by reference in its entirety.TECHNICAL FIELD

[0002] The present disclosure relates to electric power transmission and distribution operations, and more particularly to systems and methods for stringing lines with unmanned aerial vehicles (UAVs) and for monitoring linear tension between a UAV-carried nonconductive line and a ground-managed lead line.BACKGROUND

[0003] Lead line stringing for conductor installation traditionally relies on bucket trucks or manned helicopters, which are costly, equipment-intensive, and impose environmental, noise, and safety burdens. UAV-based approaches can lower cost and impact, but known methods either mount lines directly to the aircraft without tension monitoring or rely on ground-based tension spools coordinated with the pilot — leaving the aircraft vulnerable to overloads from excessive tension and complicating field operations.

[0004] In industry practice, a lightweight rope is flown through a stringing block at a structure top and then used to pull progressively heavier lines and ultimately the conductor. Maintaining sufficient tension to keep the line aloft while avoiding overloads beyond the UAV’s payload capability is crucial for flight stability and safety. Prior approaches that infer risk from angular thresholds may not alert in vertical or near-vertical pulls and may not correlate accurately to linear tension; furthermore, UAV systems in the field often lack a UAV-side linear tension monitoring and alerting mechanism set to the aircraft’s safe operating limit.SUMMARY

[0005] Disclosed are systems and methods to string a lead line using a UAV coupled via a nonconductive line to a tension monitoring system that measures linear tension between the UAV side and the lead line and provides visual and / or electronic alerts upon reaching a preset threshold, enabling the pilot to avoid exceeding the aircraft’s payloadAttorney Docket No.: 106652-00038WO_BEIR09PCTcapacity. The tension monitoring system may be adjustable mechanically or electronically to match the aircraft model and mission profile. The system may optionally include line markers, ballast for airframe clearance, and wireless signaling to a controller or assistant device to convey tension status.

[0006] In various embodiments, the tension monitoring device is positioned in-line between a UAV-connected nonconductive line and the lead line, with housings that translate under load against a biasing mechanism to trigger an alert at a setpoint; alternative embodiments include spring-compression geometries and highly simplified elastic / indicator-line arrangements that give unmistakable visual indication of tension state.

[0007] The invention facilitates low-cost, easily deployable lead line stringing, reduces or eliminates the need for large ground spools or manned aircraft, and improves safety by preventing overload-induced loss of control while maintaining sufficient tension to keep the line clear of obstacles.

[0008] In an embodiment of the invention, a tension monitoring device includes a first connector configured to connect to a first line, a second connector configured to connect to a second line, wherein the second line is configured to connect to an unmanned aerial vehicle (UAV), and a controller configured to measure linear tension between the first line and the second line based on an adjustable biasing system.

[0009] These and other embodiments can each optionally include one or more of the following features.

[0010] In some embodiments of the invention, in response to the linear tension exceeding a tension threshold, the controller is configured to provide an alert. In some embodiments of the invention, the alert includes a high-intensity LED. In some embodiments of the invention, the alert includes a wireless transmitter configured to send a notification to a UAV controller or handheld device.

[0011] In some embodiments of the invention, the adjustable biasing system includes a coil spring disposed between first and second housings that translate relative to one another under tensile load to actuate a switch at a preset tension. In some embodiments of the invention, the tension monitoring device further includes a screw-adjustable spring seat configured to alter a spring preload to change a tension threshold. In some embodiments of the invention, the adjustable biasing system includes a spring compression assembly arranged such that increasing separation of the first and second connectors compresses the spring along a device axis.Attorney Docket No.: 106652-00038WO_BEIR09PCT

[0012] In some embodiments of the invention, the tension monitoring device further includes an elastic line and an indicator line arranged in parallel to provide a visual alignment cue indicating achievement of a preset tension.

[0013] In some embodiments of the invention, the second line includes a ballast weight proximate the tension monitoring to maintain clearance from UAV landing gear and rotors.

[0014] In some embodiments of the invention, the controller is configured to support multiple UAV payload profiles by storing or receiving a setpoint associated with a selected UAV model.

[0015] In some embodiments of the invention, the first and second connectors include carabiners or rings rated to exceed the device’s maximum threshold tension by a safety factor.

[0016] In some embodiments of the invention, the adjustable biasing system includes a housing that includes at least two sections. In some embodiments of the invention, the adjustable biasing system includes a polymeric enclosure with a linear guide slot constraining relative translation between the at least two sections of the housing.

[0017] In some embodiments of the invention, the adjustable biasing system filters transient loads and requires a dwell time above a threshold before triggering an alert. In some embodiments of the invention, the second line is a non-conductive insulated line.

[0018] In an embodiment of the invention, a method includes the actions of: attaching a first line to an unmanned aerial vehicle (UAV) via an attachment device, attaching the first line to a tension monitoring system, attaching a second line to the tension monitoring system, piloting the UAV to a first position adjacent to and at an altitude that is higher than an energized electrical power line and / or a splice on the energized electrical power line upon which it is desired to attach the second line at an installation location, and piloting the UAV to a second position from the first position based on receiving an alert notification from the tension monitoring system, wherein the alert notification is associated with a particular measured tension measured by the tension monitoring system between the first line and the second line.

[0019] These and other embodiments can each optionally include one or more of the following features.

[0020] In some embodiments of the invention, the method further includes the actions of setting a tension threshold in the tension monitoring system that is lower than the UAV’s maximum continuous payload to account for gusts and transients. In some embodiments of the invention, the method further includes the actions of observing a visual alert on the device within a live video feed from the UAV and reducing pull when the alert is activated.Attorney Docket No.: 106652-00038WO_BEIR09PCT

[0021] In some embodiments of the invention, the method further includes the actions of receiving, at a handheld or UAV controller, a wireless alert generated by the tension monitoring system upon reaching the threshold. In some embodiments of the invention, the method further includes the actions of affixing a marker ball to the second line as a distance and alignment indicator to facilitate placement into a stringing block.

[0022] In some embodiments of the invention, the method further includes the actions of maintaining slight tension sufficient to hold the second line clear of ground obstacles while avoiding activation of the threshold alert. In some embodiments of the invention, the method further includes the actions of logging alert events for post-mission review to refine thresholds for subsequent missions using different UAV models.

[0023] This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used in isolation as an aid in determining the scope of the claimed subject matter.BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate various embodiments of the present invention and, together with the general description of the invention given above, and the detailed description of the embodiments given below, serve to explain the embodiments of the invention. In the drawings, like reference numerals are used to indicate like parts in the various views.

[0025] FIG. 1A is a perspective operational view showing a unmanned aerial vehicle (UAV), a UAV operator, and an assistant with a device aligning a lead line on a stringing block onto a powerline using a tension monitoring system, in accordance with embodiments of the present invention.

[0026] FIG. 1 B is a perspective operational view similar to FIG. 1 A, where the operator uses a controller live view to visually confirm tension indicators on a tension monitoring system from the UAV’s onboard camera, in accordance with embodiments of the present invention.

[0027] FIG. 2 illustrates an example tension monitoring system, in accordance with embodiments of the present invention.

[0028] FIG. 3A illustrates an example tension monitoring system that includes a compression spring system, in accordance with embodiments of the present invention.

[0029] FIG. 3B illustrates a perspective view of a portion of the compression spring system of FIG. 3A, in accordance with embodiments of the present invention.Attorney Docket No.: 106652-00038WO_BEIR09PCT

[0030] FIGS. 4A and 4B illustrate an example tension monitoring system, in accordance with embodiments of the present invention.

[0031] FIGS. 5A and 5B illustrate an example tension monitoring system utilizing a solid-state load cell, in accordance with embodiments of the present invention.DETAILED DESCRIPTION

[0032] Certain terminology is used in the following description for convenience only and is not limiting. The words “lower,” “bottom,” “upper,” and “top” designate directions in the drawings to which reference is made. The words “inwardly,” “outwardly,” “upwardly” and “downwardly” refer to directions toward and away from, respectively, the geometric center of the device, and designated parts thereof, in accordance with the present disclosure. Unless specifically set forth herein, the terms “a,” “an” and “the” are not limited to one element, but instead should be read as meaning “at least one.” The terminology includes the words noted above, derivatives thereof and words of similar import.

[0033] This invention is used in the electrical utility industry to assist with conductor stringing operations in the installation of new electrical conductors to pole or tower infrastructure during construction or repairs. It is used with an unmanned aerial system to pull a thin rope line into a target stringing block located near the top of a pole or tower, with the lead line being used afterward to pull subsequent larger lines and eventually conductors. The stringing of the lead line is traditionally done with helicopters or bucket trucks, with unmanned aerial systems offering a lower cost and lower impact method. Existing state of the art drone-based solutions exist, with some using complex ground based tensioning spools to release the stringing line. The tensioning spool is adjusted in coordination with the aircraft pilot to maintain the proper amount of tension and not exceed the aircraft’s capabilities. This invention’s tension monitor will monitor tension from the aircraft side rather than the ground side.

[0034] The present invention relates to a device, and methods for using the device, to be used for monitoring tension between two lines using a unmanned aerial system (e.g., a UAV). This disclosure offers a simplified method for pulling the lead line into a stringing block with an unmanned aerial system and lightweight easily transportable equipment. The system can be carried by the aircraft from a landing zone quickly through the air to set a lead line into a stringing block, and then released from the aircraft afterward to crew on the ground or in the tower. This invention and method is low cost, lightweight, low profile, and does not require additional heavy equipment to operate. It enables stringing of a lead line without requiring manned aircraft or manned bucket truck, and thus lower emissions and environmental and noise impact.Attorney Docket No.: 106652-00038WG_BEIR09PCT

[0035] FIG. 1A and FIG. 1B provide a tension monitoring system 100 for UAV-assisted lead line stringing includes: a UAV 10; a nonconductive line 50 selectively attached to the UAV 10; a tension monitoring system 20 coupled in-line; a lead line 30; a UAV operator 70 with controller 80; and optionally an assistant 60 with a device 65 to stage and align the lead line near a stringing block 40 on an electrical power pole or tower (e.g., electrical powerline system 45).

[0036] In FIG. 1 A, the assistant 60 may observe a visible alert (e.g., an LED) on the tension monitoring system 20 and communicate with the operator 70, who controls the UAV 10 via controller 85, to prevent further tension increases. In FIG. 1B, the operator 70 may observe the alert via the controller’s live view 85 from the UAV camera, enabling single-operator workflows.

[0037] In some embodiments, the nonconductive line 50 may incorporate a ballast weight near the lower end to keep line systems clear of landing gear and rotors. The lead line 30 may optionally include a marker ball as a distance / tension proxy to aid alignment into the stringing block.

[0038] In some embodiments, the nonconductive line is preferably dielectric and terminated with loops for quick coupling at the UAV side and at the tension monitor. A ballast weight at the nonconductive line may maintain safe separation from landing gear and rotors during maneuvering. The lead line is a lightweight rope on a ground spool, optionally bearing a marker ball as a distance / tension proxy for alignment into the stringing block.

[0039] The tension monitor (tension monitoring system 20) is a mechanical and electronic device that connects between a nonconductive line 50 (connected to a UAV) and a thin lead line 30. The tension monitoring system 20 may provide a visual alert to an aircraft pilot when the line tension exceeds the aircraft’s payload capacity (which can lead to loss of control). A monitor, with connection points on either end of its enclosure, pulls apart under tension and activates an LED light (e.g., an alert notification) when a predetermined amount of tension is applied (e.g., greater than seven pounds of pressure). The tension monitoring system 20 is adjustable depending on the payload capacity and can be set at a desired threshold as a warning that the aircraft is close to its maximum payload. When the light activates (e.g., an alert notification) the pilot can see from the ground or through the aircraft’s camera that the aircraft’s payload capacity limit is being approached.

[0040] In some embodiments, the nonconductive insulated line 50 includes a desired length terminated with loops at both ends to connect to the aircraft at one end and the rest of the system at the other end. In some embodiments, the tension monitoring systemAttorney Docket No.: 106652-00038WO_BEIR09PCTalerts the pilot of the aircraft to excess tension on the aircraft. Exceeding the aircraft’s payload capacity is possible with excess tension from the pulled line and can result in loss of control of the aircraft. In some embodiments, a ballast weight may be used (e.g., added to an end of the nonconductive line 50) to keep the system away from the landing gear and props of the aircraft. In some embodiments, a thin lightweight rope lead line 30 is connected to the rest of the system at the aircraft side and to a spool on the ground at the other end. In some embodiments, an optional marker ball may be attached to the lead line as a visual indicator of distance from the aircraft to assist with lining up the lead line into the stringing block.

[0041] In some embodiments, the alert notification may include any light component that alerts an end user or operative of the UAV. Additionally, or alternatively, in some embodiments, the alert notification may include a wireless signal to an operating device which in turn may alert the user, or the alert notification may include an audible cue to the end user regarding the tension.

[0042] In some embodiments, a tension monitoring system described herein may support a multi-modal alert strategy: high-intensity LEDs visible in daylight; audible beepers for nearby assistants; and wireless signaling to operator handsets or UAV GCS / controller interfaces. The live video feed (controller 80 live view 85) allows singleoperator flights to observe device state and adjust flight path or speed to maintain tension within limits.

[0043] In some embodiments, a bystander assistant equipped with a device 65 can provide immediate voice or radio feedback when visual alerts are observed, which is useful in settings where the operator and assistant are separated by terrain or structures.

[0044] Unlike angle-triggered releases, the disclosed systems measure linear tension regardless of relative angle, providing alerts even in vertical ascent or descent where angular thresholds would not actuate, thereby avoiding miscorrelation between angle and actual aircraft load. This allows maintaining minimal but adequate tension to keep the line off the ground while warning at the configured limit to protect aircraft control authority. Unlike angle-triggered releases, the disclosed systems measure linear tension regardless of relative angle, providing alerts even in vertical ascent or descent where angular thresholds would not actuate, thereby avoiding miscorrelation between angle and actual aircraft load. This allows maintaining minimal but adequate tension to keep the line off the ground while warning at the configured limit to protect aircraft control authority.

[0045] FIG. 2 illustrates an example tension monitoring system 200, in accordance with embodiments of the present invention. The tension monitoring system 200 includes a first connector 202 for the lead line, a second connector 204 for the nonconductive line, aAttorney Docket No.: 106652-00038WO_BEIR09PCTtwo-part housing 210, 212 that translates under tensile load, a spring or equivalent biasing element 240 with an adjustable mounting / screw 250 to set a tension threshold, a switch or sensor, a controller, and an alert component 230 (e.g., LED light, audible indicator, or electronic telemetry to a handset or UAV controller). The housing 212 houses the adjustment screw 260 and spring 265, and the one or more control components (e.g., battery 285, switch 270, controller 280).

[0046] In an exemplary implementation, tuning of the endpoint is not dependent on the spring attachment 250. In other words, the spring attachment 250 is a structural bar to keep the spring assembly in place and travel along the movement slot as the two ends (connector-1 202 and connector-2204) are pulled apart. The adjustment screw 260 tunes the endpoint specifically by adjusting the amount of force needed on the spring 265 to activate the switch 270. The slot for movement is for housing translation and not necessarily for spring travel.

[0047] The housings 210, 212 are configured to slide relative to each other along a guided path when line tension increases, compressing or extending the spring mechanism (e.g., spring 265) until a preset threshold actuates the alert. The threshold may be field-adjustable (e.g., 7 Ibf for a particular UAV) to accommodate different UAV payload capabilities and mission requirements.

[0048] An alert component (e.g, tension alert component 230) can be configured for high-visibility recognition on the ground and in the UAV’s down-looking video feed.Alternatively, or additionally, in some embodiments, short-range wireless signaling (e.g., RF signals, and the like) may be used to notify the operator device or the UAV controller 80 when the threshold is reached. The alert component (e.g., tension alert component 230, i.e. and LED light) may be communicatively coupled to the controller 280, such that when the switch 270 is activated, the controller 280 may activate a light component (and / or audio component) of the tension alert component 230.

[0049] FIG. 3A illustrates an example tension monitoring system 300, in accordance with embodiments of the present invention. The tension monitoring system 300 includes the connectors 302, 304 which are coupled via members that, under increasing line separation, compress a compression spring system 340 axially to a threshold that actuates a tension alert component 330. The resulting geometry provides a compact, robust arrangement with the same alerting modalities described above. In some embodiments, the electronic or mechanical setpoint can be tailored to the UAV’s allowable tension window so that the aircraft maintains sufficient line lift without exceeding stability and payload margins.Attorney Docket No.: 106652-00038WG_BEIR09PCT

[0050] FIG. 3B illustrates a perspective view of a portion of the compression spring system 340 of FIG. 3A, in accordance with embodiments of the present invention. In particular, FIG. 3B illustrates an example adjustment screw 510 associated with the compression spring system 340 of the tension monitoring system 300 of FIG. 3A. For example, FIG. 3B depicts the adjustment screw 310, a switch 325, and a spring 320.

[0051] FIG. 4A and FIG. 4B illustrate an example tension monitoring system 400, in accordance with embodiments of the present invention. The tension monitoring system 400 includes an elastic line 410 runs in parallel with an indicator line 420; when under low tension, the indicator line remains slack or offset, while at a threshold the two lines align tautly in a clearly visible configuration— readable by an assistant or operator via onboard camera — signaling that further increase would exceed the safe limit. This embodiment provides a low-complexity field solution, requiring no electronics, and may be used as a backup or as a primary device for operators preferring purely visual cues.

[0052] FIG. 5A and FIG. 5B illustrates an example tension monitoring system 500 utilizing a solid-state load cell 550, in accordance with embodiments of the present invention. In particular, FIG. 5A illustrates an outer view of the tension monitoring system 500, and includes an outer case 510, a display screen 502 (e.g., an Organic Light-Emitting Diode (OLED) or the like), and menu buttons 504, that allow an operator to change one or more settings via the controller board 540 (e.g., tension threshold, alert settings, etc.). The outer case is coupled to the connectors 502, 504.

[0053] FIG. 5B illustrates an inside view of the tension monitoring system 500, and includes an inner case 520, a battery 530, controller board 540, and a solid-state load cell 550. For the alarm system, the tension monitoring system 500 includes a speaker 560, and one or more LED lights 570, which are communicatively coupled to the controller board 540 for operation. The tension monitoring system 500 includes the connectors 502, 504 which are coupled via members that, under increasing line separation, apply a force axially to a threshold that actuates a solid-state load cell 550. In an exemplary embodiment, the solid-state load cell 550 is an advanced force sensorthat uses semiconductor technology to measure weight or force by detecting changes in frequency, offering higher precision, stability, and digital output compared to traditional strain gauge cells, effectively eliminating interference and providing direct digital readings for accurate industrial weighing and monitoring. The resulting geometry provides a compact, robust arrangement with the same alerting modalities described above. In some embodiments, the electronic setpoint can be tailored to the UAV’s allowable tension window so that the aircraft maintains sufficient line lift without exceeding stability and payload margins.Attorney Docket No.: 106652-00038WO_BEIRD9PCT

[0054] An exemplary embodiment for a method of operation using one or more of the tension monitoring systems described herein may include one or more of the following actions. The actions may include attaching a nonconductive line to the UAV, couple the tension monitoring system in-line, and attach a lead line to the distal connector. The actions may further include configuring the device’s tension threshold to the UAV’s payload margin for the operation. The actions may further include piloting the UAV to position and altitude appropriate to thread the lead line into a stringing block; maintain sufficient forward speed and trajectory to keep line aloft while observing visual or electronic alerts. The actions may further include, upon alert, reduce pulling force or adjust flight path to remain within safe limits; once set in the block, release the line system to ground crews.

[0055] In some embodiments of the invention, the method further includes the actions of setting a tension threshold in the tension monitoring system that is lower than the UAV’s maximum continuous payload to account for gusts and transients. In some embodiments of the invention, the method further includes the actions of observing a visual alert on the device within a live video feed from the UAV and reducing pull when the alert is activated.

[0056] In some embodiments of the invention, the method further includes the actions of receiving, at a handheld or UAV controller, a wireless alert generated by the tension monitoring system upon reaching the threshold. In some embodiments of the invention, the method further includes the actions of affixing a marker ball to the second line as a distance and alignment indicator to facilitate placement into a stringing block.

[0057] In some embodiments of the invention, the method further includes the actions of maintaining slight tension sufficient to hold the second line clear of ground obstacles while avoiding activation of the threshold alert. In some embodiments of the invention, the method further includes the actions of logging alert events for post-mission review to refine thresholds for subsequent missions using different UAV models.

[0058] In some embodiments, device housings may be machined or molded polymeric enclosures with integral slide guides; connectors may be stainless rings or carabiners rated above device thresholds; springs or elastomeric elements are selected for stability across temperature and humidity ranges encountered in field operations; and lights are high-intensity LEDs with diffusers positioned for visibility in the UAV camera frame. In some embodiments, nonconductive lines are dielectric ropes with end loops; ballast may be nonferrous.

[0059] In some embodiments, setting the alert threshold below the UAV’s maximum steady payload margin is recommended to account for gusts, pilot inputs, and transient loads; the operator should confirm visibility of the alert device in the live view duringAttorney Docket No.: 106652-00038WO_BEIR09PCTpreflight; and assistant communication protocols should be established to arrest tension increases on first alert. In proximity to energized lines, maintain approach distances per applicable codes, leveraging practices and frames disclosed in related filings.

[0060] The disclosed systems enable rapid, low-cost, and lower-risk lead line stringing for electric utilities and contractors, with portability for field crews, and alerting that preserves UAV control while maintaining adequate line lift. The technology is applicable to distribution and transmission environments and can be integrated with existing UAV platforms without truck-mounted tensioners.

[0061] The embodiments described in connection with FIGS. 1A-5 and the associated structures and methods support and enable the claimed subject matter. Variations, including alternative sensors, mechanical configurations, wireless protocols, and visual schemes, fall within the scope of these teachings.

[0062] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and / or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0063] The corresponding structures, materials, acts, and equivalents of all means or step plus function elements in the claims below are intended to include any structure, material, or act for performing the function in combination with other claimed elements as specifically claimed. The description of the present invention has been presented for purposes of illustration and description, but is not intended to be exhaustive or limited to the invention in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the invention. The embodiment was chosen and described in order to best explain the principles of the invention and the practical application, and to enable others of ordinary skill in the art to understand the invention for various embodiments with various modifications as are suited to the particular use contemplated.

Claims

Attorney Docket No.: 106652-00038WO_BEIR09PCTCLAIMSWhat is claimed is:

1. A tension monitoring device comprising:a first connector configured to connect to a first line;a second connector configured to connect to a second line, wherein the second line is configured to connect to an unmanned aerial vehicle (UAV); anda controller configured to measure linear tension between the first line and the second line based on an adjustable biasing system.

2. The device of claim 1 , wherein, in response to the linear tension exceeding a tension threshold, the controller is configured to provide an alert.

3. The device of claim 2, wherein the alert comprises a high-intensity LED.

4. The device of claim 2, wherein the alert comprises a wireless transmitter configured to send a notification to a UAV controller or handheld device.

5. The device of claim 1 , wherein the adjustable biasing system comprises a coil spring disposed between first and second housings that translate relative to one another under tensile load to actuate a switch at a preset tension.

6. The device of claim 5, further comprising a screw-adjustable spring seat configured to alter a spring preload to change a tension threshold.

7. The device of claim 5, wherein the adjustable biasing system comprises a spring compression assembly arranged such that increasing separation of the first and second connectors compresses the spring along a device axis.

8. The device of claim 1 , further comprising an elastic line and an indicator line arranged in parallel to provide a visual alignment cue indicating achievement of a preset tension.

9. The device of claim 1 , wherein the second line includes a ballast weight proximate the tension monitoring to maintain clearance from UAV landing gear and rotors.Attorney Docket No.: 106652-00038WO_BEIR09PCT10. The device of claim 1 , wherein the controller is configured to support multiple UAV payload profiles by storing or receiving a setpoint associated with a selected UAV model.

11. The device of claim 1 , wherein the first and second connectors comprise carabiners or rings rated to exceed a maximum threshold tension by a safety factor.

12. The device of claim 1 , wherein the adjustable biasing system comprises a housing that comprises at least two sections.

13. The device of claim 12, wherein the adjustable biasing system comprises a polymeric enclosure with a linear guide slot constraining relative translation between the at least two sections of the housing.

14. The device of claim 1 , wherein the adjustable biasing system filters transient loads and requires a dwell time above a threshold before triggering an alert.

15. The device of claim 1 , wherein the second line is a non-conductive insulated line.

16. A method comprising:attaching a first line to an unmanned aerial vehicle (UAV) via an attachment device;attaching the first line to a tension monitoring system;attaching a second line to the tension monitoring system;piloting the UAV to a first position adjacent to and at an altitude that is higher than an energized electrical power line and / or a splice on the energized electrical power line upon which it is desired to attach the second line at an installation location; and piloting the UAV to a second position from the first position based on receiving an alert notification from the tension monitoring system, wherein the alert notification is associated with a particular measured tension measured by the tension monitoring system between the first line and the second line.Attorney Docket No.: 106652-00038WO_BEIR09PCT17. The method of claim 16, further comprising setting a tension threshold in the tension monitoring system that is lower than the UAV’s maximum continuous payload to account for gusts and transients.

18. The method of claim 16, further comprising observing a visual alert on the device within a live video feed from the UAV and reducing pull when the alert is activated.

19. The method of claim 16, further comprising receiving, at a handheld or UAV controller, a wireless alert generated by the tension monitoring system upon reaching a threshold.

20. The method of claim 16, further comprising affixing a marker ball to the second line as a distance and alignment indicator to facilitate placement into a stringing block.

21. The method of claim 16, further comprising maintaining slight tension sufficient to hold the second line clear of ground obstacles while avoiding activation of a threshold alert.

22. The method of claim 16, further comprising logging alert events for postmission review to refine thresholds for subsequent missions using different UAV models.

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