Method for adjusting laser power in long-distance foreign matter removing process of power transmission line

Abstract

This specification discloses a method for adjusting laser power during remote foreign object removal from power transmission lines. The method includes: acquiring real-time images of the laser operation area and forming a continuous video stream; identifying and classifying multiple objects within the area covered by the real-time images; for each identified object, associating a maximum tolerable laser power based on its material properties, wherein the maximum tolerable laser power is determined based on the material damage energy threshold, the laser irradiation time on the object, and the laser spot area; determining a collimator neighborhood region centered on the current laser emission point, and analyzing the power tolerance of different objects within this region based on the associated maximum tolerable laser power; calculating the maximum permissible safe output power at the current moment based on the laser's current motion direction, tracking speed, and the local safe power distribution; and dynamically adjusting the laser's output power in real time based on the maximum safe output power.

Description

Technical Field

[0001] This application relates to the field of intelligent operation and maintenance technology for power transmission lines, and in particular to a method for adjusting laser power during remote foreign object removal from power transmission lines. Background Technology

[0002] In the field of intelligent operation and maintenance of power transmission lines, the use of laser technology for remote removal of foreign objects is increasingly being applied to drone or fixed platform operations due to its advantages of being non-contact and highly efficient. To improve removal efficiency, the system often integrates automatic tracking functionality, enabling the laser beam to continuously target targets that sway with the wind or whose position changes.

[0003] However, during dynamic tracking of the laser beam, its emission point constantly moves, and its path inevitably briefly passes over non-target objects such as the conductor itself, insulators, and hardware, or sweeps across background elements like trees, tower components, or even occasionally, people or animals that enter the field of view. Existing technologies typically employ a fixed power output strategy during this dynamic process, or only cut off the beam when it directly contacts a high-risk target. This approach has significant limitations: a high-power laser may sweep across sensitive non-target areas for an extremely short time, potentially causing irreversible damage even if it doesn't linger for an extended period. Summary of the Invention

[0004] This specification provides an embodiment of a method for adjusting laser power during remote foreign object removal from power transmission lines, in order to solve at least one of the technical problems mentioned above.

[0005] To solve the above-mentioned technical problems, the embodiments in this specification are implemented as follows: This specification provides an embodiment of a method for adjusting laser power during remote foreign object removal from power transmission lines, including: Acquire real-time images of the laser operation area and generate a continuous video stream; Based on the real-time image, multiple objects within the area covered by the real-time image are identified and classified, and the multiple objects include at least target foreign objects, wires, and insulators; For each type of identified object, a maximum tolerable laser power is associated with its material properties, wherein the maximum tolerable laser power is determined based on the material damage energy threshold, the laser irradiation time on the object, and the laser spot area. A collimator neighborhood region is determined with the current laser emission point as the center, and the power tolerance of different objects in the region is analyzed based on the associated maximum tolerable laser power to form a local safe power distribution for constraining laser power. Based on the laser's current direction of motion, tracking speed, and the local safe power distribution, the maximum safe output power allowed at the current moment is calculated. Based on the maximum safe output power, the output power of the laser is dynamically adjusted in real time.

[0006] In some alternative implementations, the maximum withstandable laser power Calculated using the following formula: in, The energy threshold for material damage. The time it takes for the laser spot to remain on the object. The laser spot area is denoted as .

[0007] In some alternative implementations, the method for determining the crosshair neighborhood region is one of the following: In the image pixel coordinate system, using the laser spot pixel coordinates Centered on A circular region with a radius of pixels: In the physical space coordinate system, the spatial position of the laser emission point Centered on A spherical region with a radius of meters: .

[0008] In some alternative implementations, forming a local safe power distribution for constraining laser power specifically involves: Construct the power constraint distribution function within the neighborhood of the quasi-star : in, The first in the neighborhood of the crosshair The maximum laser power that an object can withstand. This is the preset safe power limit for the background area.

[0009] In some optional implementations, the calculation of the maximum safe output power allowed at the current moment specifically includes: Based on the current position of the laser Unit vector of direction of motion and tracking speed Predict its future prediction time interval Internal movement path: Extract the region traversed by the predicted path and the neighborhood region of the crosshair. Calculate the power limit value by finding the minimum maximum power that all objects within the enclosure can withstand. : Combined with the minimum power required to remove the target foreign object Determine the current maximum safe output power. : .

[0010] In some optional implementations, the real-time dynamic adjustment of the laser's output power further includes adjusting the maximum safe output power based on the following formula. Smoothing is performed to obtain the final output power. : in, For smoothing coefficients, , The sampling time interval; Wherein, the smoothing coefficient Based on the power limit value, the following formula is used. With the power required for cleaning The proximity level is dynamically adjusted: in, and These are the minimum and maximum values ​​of the smoothing coefficient, respectively. For the standard Sigmoid function, These are the sensitivity adjustment parameters.

[0011] In some optional implementations, the real-time dynamic adjustment further includes a constraint step based on a power change rate limit, specifically including: Calculate power adjustment amount ; Based on the preset maximum power rise rate and maximum rate of descent The final output power is determined according to the following rules. : .

[0012] In some alternative implementations, the power limit value is calculated... At that time, for the neighborhood region of the crosshair Maximum power that different objects inside can withstand Apply dynamic weights based on spatial distance and relative velocity, and calculate using a weighted minimum value: Among them, the weighting coefficient From objects To the current laser emission point normalized distance and its relative velocity with the laser spot The decision is made jointly, and the following formula is used for calculation: In the formula, and These are the characteristic distance constant and the characteristic velocity constant, respectively.

[0013] In some alternative implementations, the prediction time interval Based on the current tracking speed of the laser and the complexity of environmental goals Perform adaptive adjustments: in, As the baseline prediction time, For reference tracking speed, This is the complexity impact coefficient. This is an environmental complexity index calculated based on the number of different types of objects identified within the neighborhood of the crosshair and their distribution dispersion.

[0014] In some alternative implementations, for those with known reflectivity and thermal diffusivity The object, associated with the maximum withstandable laser power A safety reduction needs to be applied based on its optical and thermal properties to obtain the corrected safe power limit. : Among them, the reduction factor Calculated by the following formula, and : In the formula, Positive weighting coefficients are used to adjust the degree of influence of reflectivity and thermal diffusivity, respectively. The reference thermal diffusivity is used.

[0015] One embodiment of this specification can achieve at least the following beneficial effects: In this technical solution, when remotely removing foreign objects from transmission lines using lasers, the traditional post-operation shutdown protection method is not relied upon. Instead, dynamic safety control is achieved through the following process: First, various objects within the field of view are identified in real time, and their maximum tolerable laser power is correlated based on their material properties. Then, a neighborhood is defined centered on the real-time laser emission point, and a local power distribution reflecting the instantaneous safety limit of this area is formed based on the aforementioned power constraints. Next, the distribution is analyzed proactively in conjunction with the real-time direction and speed of the laser, and the maximum permissible safe output power at the current moment is dynamically calculated. Finally, the laser output power is adjusted in real time based on the calculation results. Because this technical solution limits the output power in advance based on the power distribution constraints ahead of the laser beam's path before it reaches the sensitive object, safety control can shift from post-operation response to pre-operation constraints and dynamic tracking. This effectively avoids the instantaneous damage that may be caused when a high-power laser beam briefly sweeps across non-target objects such as conductors and insulators in complex dynamic tracking scenarios, improving the safety of the operation while ensuring removal efficiency. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments or prior art of this specification, the drawings used in the description of the embodiments or prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a flowchart illustrating a method for adjusting laser power during remote foreign object removal from power transmission lines, as provided in the embodiments of this specification. Figure 2 For corresponding Figure 1 A schematic diagram of a laser power adjustment device used in the remote foreign object removal process of a power transmission line. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of one or more embodiments of this specification clearer, the technical solutions of one or more embodiments of this specification will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this specification, and not all of them. Based on the embodiments in this specification, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of one or more embodiments of this specification.

[0019] It should be understood that although the terms first, second, third, etc., may be used in this application to describe various information, this information should not be limited to these terms. These terms are only used to distinguish information of the same type from one another.

[0020] Figure 1 This is a flowchart illustrating a method for adjusting laser power during remote foreign object removal from power transmission lines, as provided in the embodiments of this specification. Figure 2 For corresponding Figure 1 A schematic diagram of a laser power adjustment device used in the remote foreign object removal process of a power transmission line.

[0021] This application provides a method for adjusting laser power during remote foreign object removal from power transmission lines. In the scenario of automatic tracking and removal of foreign objects remotely from power transmission lines, this method can proactively predict risks and impose fine-grained power constraints based on environmental differences, thus ensuring operational efficiency while eliminating the risk of accidental damage during the dynamic process. Figure 1 As shown, the method may include: Step 102: Acquire real-time images of the laser operation area and generate a continuous video stream.

[0022] In the embodiments described in this specification, an optical imaging device deployed on the laser removal device can continuously and synchronously capture visual information of the transmission line section and its surrounding environment targeted by the current laser operation, thereby obtaining a series of temporally coherent image sequences reflecting the instantaneous state of the area. Specifically, the imaging device can be a high-resolution visible light camera, which can be fixed to the operating platform or mounted on a mobile carrier such as a drone. Its field of view must cover the range where the laser spot may move, as well as the relevant line equipment and background environment. The acquired real-time image sequence continuously constitutes a video stream in the time dimension, and its frame rate and resolution must meet the requirements of subsequent real-time processing.

[0023] Step 104: Based on the real-time image, identify and classify multiple objects within the area covered by the real-time image, wherein the multiple objects include at least target foreign objects, wires, and insulators.

[0024] In the embodiments of this specification, image processing and artificial intelligence recognition algorithms can be used to analyze each frame of the continuous video stream obtained in step 102, thereby detecting each independent object in the image and classifying these objects into predefined semantic categories based on their visual features, morphological structure and contextual scene information.

[0025] Specifically, the identification and classification process requires distinguishing at least the following key object categories: target foreign objects, conductors, and insulators. Target foreign objects can refer to non-equipment objects suspended, wrapped around, or attached to transmission lines, such as plastic film, kite strings, balloons, and other foreign objects that may affect the safe operation of the line. Conductors refer to the physical metal lines that transmit electrical energy, while insulators are devices used to support and fix conductors and ensure electrical isolation.

[0026] Step 106: For each type of identified object, associate a maximum tolerable laser power with its material properties, wherein the maximum tolerable laser power is determined based on the material damage energy threshold, the laser irradiation time on the object, and the laser spot area.

[0027] In the embodiments of this specification, after object identification and classification are completed, a corresponding safe upper limit value for laser power is assigned to each type of object based on the physical and chemical properties of its constituent materials. This value represents the maximum laser irradiation power that the surface of this type of object can withstand without causing damage, serving as one of the bases for subsequent safe power constraints. Specifically, the determination of this maximum tolerable laser power can be based on three parameters: the material damage energy threshold, the laser irradiation time on the object, and the laser spot area. The material damage energy threshold reflects the minimum energy required for irreversible damage to the object's material under laser irradiation; the irradiation time relates to the duration the laser spot may remain on the object; and the spot area is related to the energy density distribution. By integrating these parameters in this step, differentiated safe power thresholds can be established for different types of objects such as wires, insulators, and target foreign objects.

[0028] Step 108: Determine a collimator neighborhood region centered on the current laser emission point, and analyze the power tolerance of different objects in the region based on the associated maximum tolerable laser power, so as to form a local safe power distribution for constraining laser power.

[0029] In the embodiments of this specification, a reticle neighborhood is defined centered on the current laser emission point. This can refer to dynamically defining a pre-defined perimeter range during real-time operation, using the current laser beam illumination point as a spatial reference center. This range is the reticle neighborhood. This neighborhood can be defined based on image pixel coordinates or mapped to an actual physical spatial scale. Its purpose is to focus on the space near the instantaneous position of the laser spot, defining a clear geographical range for the upcoming local safety analysis. Based on the associated maximum tolerable laser power, the power tolerance of different objects within this area is analyzed to form a local safe power distribution for constraining laser power. This can refer to querying the pre-associated safe power upper limit values ​​of all identified objects within the defined reticle neighborhood. By collecting and comparing these values, the overall environmental tolerance to laser power within the neighborhood can be assessed, and a distribution map reflecting the safe power upper limit of each point (or object) in space can be generated. This local safe power distribution can serve as the constraint basis for calculating the real-time allowable output power in subsequent steps.

[0030] Step 110: Calculate the maximum safe output power allowed at the current moment based on the laser's current direction of motion, tracking speed, and the local safe power distribution.

[0031] In the embodiments of this specification, after acquiring the real-time motion state of the laser spot and the safe power constraint information of the local area, a specific decision algorithm can be used to comprehensively calculate the highest power value that the laser is allowed to output at the current moment without causing damage to objects in the vicinity. The purpose of this calculation process is to achieve proactive safety control during dynamic tracking. In this calculation process, considering dynamic factors, the current motion direction of the laser determines the spatial trajectory that its spot will sweep across; the tracking speed can be used to correlate the speed at which the spot moves along this trajectory, affecting its possible dwell time on sensitive objects; and the local safe power distribution can provide the upper limit of power tolerance at each point in space through which the trajectory passes. By fusing this information, this step can predict the most stringent power constraints that the laser beam may encounter on its short-term future path, and accordingly limit the output power to a safe range in advance at the current moment, thereby avoiding the risk of "damage upon sweep," and thus realizing the extension from static area constraints to dynamic path constraints.

[0032] Step 112: Based on the maximum safe output power, dynamically adjust the output power of the laser in real time.

[0033] In the embodiments of this specification, the maximum safe output power allowed at the current moment calculated in step 110 is used as an instantaneous control reference value. Based on this, a corresponding drive command is generated and sent to the power control unit of the laser, thereby rapidly and continuously adjusting the actual beam power emitted by the laser to ensure that the laser output does not exceed the safe upper limit allowed on its trajectory at any time, while maintaining the effective removal capability of the target foreign object as much as possible.

[0034] It should be noted that the above adjustment process can be closed-loop and real-time, that is, it can continuously compare the safe power reference with the current output of the laser, and dynamically correct the output power through a feedback control mechanism, so as to transform the theoretical value of the safety constraint calculated in the aforementioned steps into the actual control action of the laser hardware device.

[0035] In this technical solution, when remotely removing foreign objects from transmission lines using lasers, the traditional post-operation shutdown protection method is not relied upon. Instead, dynamic safety control is achieved through the following process: First, various objects within the field of view are identified in real time, and their maximum tolerable laser power is correlated based on their material properties. Then, a neighborhood is defined centered on the real-time laser emission point, and a local power distribution reflecting the instantaneous safety limit of this area is formed based on the aforementioned power constraints. Next, the distribution is analyzed proactively in conjunction with the real-time direction and speed of the laser, and the maximum permissible safe output power at the current moment is dynamically calculated. Finally, the laser output power is adjusted in real time based on the calculation results. Because this technical solution limits the output power in advance based on the power distribution constraints ahead of the laser beam's path before it reaches the sensitive object, safety control can shift from post-operation response to pre-operation constraints and dynamic tracking. This effectively avoids the instantaneous damage that may be caused when a high-power laser beam briefly sweeps across non-target objects such as conductors and insulators in complex dynamic tracking scenarios, improving the safety of the operation while ensuring removal efficiency.

[0036] Based on the technical solutions described above, this specification also provides some specific implementation schemes, which are described below.

[0037] In an optional embodiment, the maximum withstandable laser power Calculated using the following formula: in, The energy threshold for material damage. The time it takes for the laser spot to remain on the object. The laser spot area is denoted as .

[0038] This embodiment provides a method for determining the maximum tolerable laser power for each type of object to be identified. The physical model is specifically derived from the formula. Given. In this formula The energy threshold for material damage refers to the minimum energy required to cause irreversible damage (such as melting, ablation, or performance failure) to a unit area of ​​a material under a specific laser wavelength and irradiation method. This value depends on the material's absorptivity, heat capacity, melting point, and other properties. This represents the possible dwell time of the laser spot at a certain position on the surface of an object. In dynamic tracking scenarios, this is closely related to the scanning speed of the laser and the relative motion between the laser spot and the object. The area of ​​the laser beam irradiated on the surface of an object determines the spatial distribution range of the energy input. In practical applications of this formula, different types of objects, such as wires (e.g., aluminum, steel), insulators (e.g., ceramics, composite polymers), and target foreign objects (e.g., plastics, fabrics), can be assigned corresponding properties by consulting a pre-set material property database or based on experimental data. value. The prediction can be made based on the dynamic tracking performance parameters of the laser system (such as maximum angular velocity and acceleration) and the working distance. Usually, a conservative value that is sufficient to cover the possible dwell time of the laser spot can be selected. Determined by the laser's optical parameters and operating distance, it is a calculable or calibrable known quantity. Using this formula, the technical solution of this embodiment can calculate differentiated values ​​for various objects with drastically different tolerances. Values, for example, metal wires have high melting points and high thermal conductivity. The value is relatively large, and the calculated value is... Relatively high; while polymer insulators or plastic foreign objects, their The value is low, corresponding to Then it will decrease significantly.

[0039] In optional embodiments, the method for determining the reticle neighborhood region can be one of the following: In the image pixel coordinate system, using the laser spot pixel coordinates Centered on A circular region with a radius of pixels: In the physical space coordinate system, the spatial position of the laser emission point Centered on A spherical region with a radius of meters: .

[0040] This embodiment provides two methods for determining the neighborhood region of the crosshair. In the first method, the pixel coordinates of the laser spot in the current real-time image frame can be obtained first. Using this coordinate as the center, a radius of The circular area of ​​a pixel is defined as the pixel-level crosshair neighborhood. Its mathematical expression is This scheme operates directly on the image data level, facilitating efficient, pixel-aligned spatial relationship calculations with AI recognition and classification results based on the same image source. For example, when the system's imaging resolution is known, the radius... The covered pixel range can be converted into an approximate physical distance (e.g., 0.5 to 1 meter), thus linking the analysis of the image space with the security assessment of the physical space.

[0041] Another definition method is to perform the definition directly in the physical space coordinate system, which is closer to the actual three-dimensional space in which the laser operates. Specifically, the actual position coordinates of the laser emission point in three-dimensional space can be determined through information such as laser ranging and pose sensors. Centered on this point, a radius of... A spherical region of 0.05 meters (e.g., 0.05 meters) is defined as the physical space quasi-spot neighborhood. Its mathematical description is This method bypasses the intermediate conversion of image pixels and can directly define the neighborhood of the laser spot in the real world.

[0042] In an optional embodiment, the formation of a local safe power distribution for constraining laser power can specifically be: Construct the power constraint distribution function within the neighborhood of the quasi-star : in, The first in the neighborhood of the crosshair The maximum laser power that an object can withstand. This is the preset safe power limit for the background area.

[0043] In this embodiment, each spatial location within the vicinity is associated with a specific safe upper limit for laser power, thereby forming a spatially continuous or discrete power constraint mapping, i.e., constructing a local safe power distribution for constraining laser power. This vicinity typically includes identified and classified objects (such as wires, insulators, target foreign objects, etc.) and background areas not identified as specific objects. For each identified object, a maximum tolerable laser power determined based on material properties has been associated with it in previous steps. For the background area, a general safe power limit can be preset. This value can be set based on the most conservative safety criteria to avoid potential damage to unknown or unidentified objects.

[0044] In the specific construction process, the range of the crosshair's neighborhood can be determined first, based on image pixel coordinates or physical space coordinates. Then, a point-by-point or region-by-region classification is performed within the neighborhood. This classification process is expressed mathematically as follows: In this process, the boundary region of an object can be determined using mask or contour information output by image segmentation or object detection algorithms, while the background region is the remaining part of the neighborhood excluding the object boundary. This process is accomplished by spatially mapping the geometric boundaries of the recognition results, ensuring that each point in the neighborhood has a clear upper limit of power.

[0045] In this embodiment, the power constraint distribution function generated in the above manner This essentially constitutes a dynamically updated safe power "map," which directly reflects the differences in the tolerance of different spatial locations within the reticle's neighborhood to laser power. Specifically, at locations containing sensitive equipment such as wires and insulators, the value is lower, with stricter constraints, while the value may be higher in areas with foreign objects or stronger background tolerance. In subsequent dynamic power adjustment, this distribution function, as one of the inputs, can be used to calculate the minimum power constraints on the real-time laser emission point and its predicted path, thereby ensuring that the laser output power is always limited to a range that the local environment can safely withstand.

[0046] In an optional embodiment, the calculation of the maximum safe output power allowed at the current moment may specifically include: Based on the current position of the laser Unit vector of direction of motion and tracking speed Predict its future prediction time interval Internal movement path: Extract the region traversed by the predicted path and the neighborhood region of the crosshair. Calculate the power limit value by finding the minimum maximum power that all objects within the enclosure can withstand. : Combined with the minimum power required to remove the target foreign object Determine the current maximum safe output power. : .

[0047] In this embodiment, the calculation of the maximum permissible safe output power at the current moment integrates spatial safety constraints and motion state prediction; this calculation is a dynamic decision-making process. Specifically, this process begins with the prediction of the short-term future motion path of the laser spot, i.e., after obtaining the current position of the laser. Unit vector representing the direction of motion and the current tracking speed Based on the assumption of uniform motion, the laser beam will... (The sentence is incomplete and requires more context to translate accurately.) The predicted path within is given by the formula The description states that this prediction extends security assessments from the current static neighborhood to a dynamic, forward-looking spatial corridor, thus providing a window of opportunity to mitigate risks in advance.

[0048] After determining the prediction path, the technical solution of this embodiment simultaneously performs power tolerance analysis on two regions: one is the crosshair neighborhood region calculated in real time. Secondly, the spatial area covered by the predicted path. Specifically, the maximum tolerable laser power values ​​of all identified objects within these two areas are extracted. And find their respective minimum values. Power limit values The value is determined by the smaller of these two minimum values, and its calculation expression is: This step ensures the global and forward-looking nature of safety constraints, meaning that it must meet both the immediate safety constraints of the current environment surrounding the laser spot and the safety constraints of the area the laser spot is about to sweep across, thereby fundamentally preventing damage to sensitive objects caused by the movement of the laser in an instant.

[0049] Ultimately, the maximum safe output power allowed at the current moment. The determination of the power limit value involves a trade-off between safety constraints and operational efficiency, namely, the power limit value calculated above. The minimum power required to effectively remove the target foreign object Compare them and take the smaller value, that is This logic ensures that the output power simultaneously meets two boundaries: on the one hand, it will not exceed the absolute safety limit determined by the safety tolerance of the environment and objects; on the other hand, when the safety limit is higher than the minimum power required for removal, the power will be constrained to a level that is just enough to complete the removal task, thereby avoiding unnecessary energy output and further improving the precision and safety of the operation process. This value is the instantaneous safety benchmark used to adjust the laser output power in real time.

[0050] In an optional embodiment, the real-time dynamic adjustment of the laser's output power may further include adjusting the maximum safe output power based on the following formula. Smoothing is performed to obtain the final output power. : in, For smoothing coefficients, , The sampling time interval; Wherein, the smoothing coefficient Based on the power limit value, the following formula is used. With the power required for cleaning The proximity level is dynamically adjusted: in, and These are the minimum and maximum values ​​of the smoothing coefficient, respectively. For the standard Sigmoid function, These are the sensitivity adjustment parameters.

[0051] In this embodiment, considering the real-time dynamic adjustment of laser power, if the calculated maximum safe output power is used... Instantaneous setting can cause a step jump in laser output power, meaning the laser output power changes abruptly from one value to another within two adjacent control cycles without any transition or gradual change, similar to a step function in mathematics. This jump not only negatively impacts the laser's operational stability and lifespan but can also affect the continuous and stable removal of target foreign objects due to drastic power fluctuations. Therefore, this embodiment introduces a smoothing mechanism, specifically, which uses a first-order recursive filtering formula. To calculate the final output power command .in, This is a smoothing coefficient, and its value ranges from 0 to 1. This is the system sampling and control cycle. The smoothing mechanism performs low-pass filtering on the power command over time; the new output power value is a weighted average of the current safe power reference and the actual output power at the previous moment. When... When the value is large, the system responds quickly and can track rapidly. Changes, when When the value is small, the system response is smooth, the output power changes smoothly, and short-term fluctuations can be effectively suppressed.

[0052] Meanwhile, to further optimize the smoothing effect and adapt it to dynamic operation scenarios, the smoothing coefficient in this scheme... It is not a fixed value, but can be dynamically adjusted based on real-time safety conditions, and the adjustment is based on the power limit value. Minimum power required to remove the target foreign object The degree of similarity. Specifically, it is determined by the formula. Implementation. Among them, and These are the preset minimum and maximum values ​​of the smoothing coefficient. For the standard Sigmoid function, This is the sensitivity adjustment parameter. The physical meaning of this dynamic adjustment strategy is that when... Much larger When this value is reached, it indicates that the current and predicted path environment is very safe, allowing the power to approach the value required for clearance. At this point, the Sigmoid function output approaches 1. Take the larger value (close to) The system responds quickly, prioritizing efficient cleanup. When Close to or even smaller When this condition occurs, it indicates the presence of sensitive objects or high-risk areas in the environment, and safety constraints are extremely strict. In this case, the output of the Sigmoid function approaches 0. Take the smaller value (close to) The system response slows down, and the output power changes extremely smoothly. This design ensures that even under high-risk scenarios, the safe power reference remains intact. A sharp decline due to sudden environmental changes, through a smaller The value can also enable the actual power command. The gradual decrease in power minimizes any uncertainty caused by sudden power command changes. Meanwhile, for the tracking control system that controls the spatial direction of the laser beam (usually composed of servo motors, galvanometers, and other actuators and their controllers), the laser itself is a dynamic load that needs to be carried and worked in coordination. Due to the drastic power fluctuations of the laser, its internal thermal state, optical performance, and even mechanical vibration characteristics may change rapidly. This mechanism in the technical solution of this embodiment can provide a stable load for the tracking control system.

[0053] In an optional embodiment, the real-time dynamic adjustment further includes a constraint step based on a power change rate limit, which may specifically include: Calculate power adjustment amount ; Based on the preset maximum power rise rate and maximum rate of descent The final output power is determined according to the following rules. : .

[0054] In this embodiment, considering that during real-time dynamic adjustment of laser power, in addition to considering the instantaneous safe power value, it is also necessary to take into account the physical response characteristics of the laser hardware and the overall control stability of the system, the output power of the laser cannot achieve a truly instantaneous jump. Excessively rapid power changes may exceed the physical capabilities of its driving circuit, leading to control failure, increased device stress, or even damage. Therefore, this embodiment introduces a constraint step based on a power change rate limit. This step first calculates the theoretical power adjustment requirement, i.e., the safe power reference at the current moment. Compared with the actual output power of the previous control cycle The difference: The difference The sign and magnitude of the value can directly reflect the trend and magnitude of the expected power change.

[0055] To ensure that power adjustment is performed smoothly within the physical limits allowed by the laser, this embodiment of the technical solution presets two parameters: the maximum power rise rate. and maximum rate of descent (Units are power / time), final output power Not directly equal to Instead, it is determined according to the following rules described above: This rule constructs a "safe change corridor" starting from the current output power and with the maximum permissible rate of change as the slope, i.e., when the theoretical adjustment amount... If the absolute value does not exceed the corresponding rate limit, adjust as needed. ;when When the positive rate of increase exceeds the maximum rate of increase, power is only allowed to increase at the maximum rate of increase during the current control cycle; conversely, when... When the negative rate exceeds the maximum decrease rate, the power is only allowed to decrease at the maximum decrease rate. This mechanism strictly limits the instantaneous slope of power change within a preset safety boundary. That is, it transforms the safety power command calculated by the upper layer, which may fluctuate drastically, into a power setpoint that the laser drive circuit can smoothly track and change. This can prevent problems such as control oscillation, optical mode degradation, or thermal management imbalance caused by sudden changes in commands, and ensure the reliability and stability of the laser removal system in long-term operation while adhering to safety constraints.

[0056] In an optional embodiment, the power limit value is calculated... At that time, for the neighborhood region of the crosshair Maximum power that different objects inside can withstand Applying dynamic weights based on spatial distance and relative velocity can be achieved using a weighted minimum calculation: Among them, the weighting coefficient From objects To the current laser emission point normalized distance and its relative velocity with the laser spot The decision is made jointly, and the following formula is used for calculation: In the formula, and These are the characteristic distance constant and the characteristic velocity constant, respectively.

[0057] In this implementation solution, the power regulation method includes a power limit value. The calculation is further refined by introducing a dynamic weighting mechanism to more accurately assess the immediate risk level posed by different objects to the current laser spot. Specifically, instead of assigning equal importance to all identified objects, a weighted evaluation is performed based on the real-time spatial and motion relationships between the objects and the laser spot. Weighting coefficients Two key factors can be considered comprehensively: one is the object. To the current laser emission point normalized distance This can reflect the urgency of potential damage, and secondly, the relative speed of motion between the object and the laser spot. This reflects the dynamic possibility of accidental intersections. In this embodiment, objects closer to the laser spot or undergoing rapid relative motion with it are assigned a higher risk weight in safety decisions, thus having a more significant limiting effect on the final allowable power limit.

[0058] This dynamic weighting mechanism is mathematically implemented as follows: weighting coefficients. The formula described above The calculation yielded the following result. and These are pre-defined positive constants, called the characteristic distance constant and the characteristic velocity constant, respectively. Their function is to normalize and scale the distance and velocity to determine the strength of their respective influence on the weight attenuation. Under this formula, when the object's distance... Smaller or relative speed The larger the value, the smaller the absolute value of the negative values ​​within the exponent, and the higher the calculated weight. The closer it is to 1, the greater the maximum power that the object can withstand. The less the weight is reduced in the calculation, the more fully the safety constraints will be reflected. Conversely, objects that are far away or have low relative speeds will have their weight significantly reduced, and their influence on the overall power limit will also weaken. Ultimately, the power limit value... The minimum value of the weighted power value sequence is obtained by calculating the following formula described above: This method allows the safety power constraint to no longer be static and homogeneous, but to become a field that dynamically adjusts with spatial distance and motion state. It can respond more sensitively and reasonably to the rapidly changing risk conditions in complex working environments, and provide a better decision baseline for power regulation while ensuring safety.

[0059] In an optional embodiment, the prediction time interval... Based on the current tracking speed of the laser and the complexity of environmental goals Perform adaptive adjustments: in, As the baseline prediction time, For reference tracking speed, This is the complexity impact coefficient. This is an environmental complexity index calculated based on the number of different types of objects identified within the neighborhood of the crosshair and their distribution dispersion.

[0060] In the technical solution of this embodiment, the predicted time interval is... It is not a fixed value, but a parameter that is adaptively adjusted according to the dynamic characteristics of the work scenario. In other words, it is the prediction duration used for forward-looking safety assessments, and needs to be matched with the laser's moving speed and the complexity of the work environment. The current tracking speed of the laser. The speed directly impacts the accuracy of predictions. Higher speeds result in greater uncertainty regarding the position of the light spot per unit time. Excessively long prediction times will lead to path estimations that deviate significantly from reality, rendering them meaningless. Simultaneously, the complexity of the environmental target... This reflects the mixed and unpredictable nature of the types, quantities, and spatial distribution of objects within the reticle's neighborhood. Higher complexity means a greater probability that the laser will encounter different types of sensitive objects at short distances, necessitating a shorter prediction field of view to focus on more pressing and certain near-end risks. Therefore, the technical solution in this embodiment... The purpose of adaptive adjustment is to achieve a dynamic balance between depth and reliability in the system's "foresight" capability.

[0061] Specifically, this adaptive adjustment process is based on the formula described above. Describe the formula. The baseline prediction time... It provides the basic order of magnitude of the time scale, the exponential term. Used for adjustment based on speed, where For reference tracking speed, when the actual speed As the value increases, the value of the exponential term decreases, thus shortening the time. ; reciprocal term Used to adjust according to environmental complexity, among which These are positive constants used to adjust the strength of the impact on complexity. The hyperbolic tangent function has a complexity index of [missing information]. Mapped to The interval ensures that the term remains positive and changes smoothly. When the complexity... When increasing, Increasing the value of the denominator leads to an increase in the value of the reciprocal term, which in turn decreases the value of the entire reciprocal term, thus shortening the fraction. Environmental complexity index The calculation is based on the number of different categories of objects identified within the reticle's neighborhood and the dispersion of their spatial distribution. The more categories of objects there are and the more dispersed and disordered their distribution, the higher the calculated value. The larger the value, the more flexible the prediction time can be in response to the operational status. In scenarios where the laser moves at low speed and the environment is simple, a longer prediction interval can be used to achieve more forward-looking protection. In scenarios where the laser moves at high speed or the environment is complex and chaotic, the prediction interval will be automatically shortened to ensure the timeliness and accuracy of risk assessment.

[0062] In optional embodiments, for those with known reflectivity... and thermal diffusivity The object, associated with the maximum withstandable laser power A safety reduction can be applied based on its optical and thermal properties to obtain the corrected safety power limit. : Among them, the reduction factor Calculated by the following formula, and : In the formula, Positive weighting coefficients are used to adjust the degree of influence of reflectivity and thermal diffusivity, respectively. The reference thermal diffusivity is used.

[0063] In this embodiment, the setting of the maximum laser power that an identified object can withstand can be further considered by taking into account the object's own optical and thermal physical properties, so as to refine the upper limit of its safe power. The principle of this correction is as follows: although basic parameters such as the material damage energy threshold can define the damage threshold under ideal conditions, in actual laser irradiation, the surface reflectivity and internal heat diffusion capacity of the object will significantly affect its actual energy coupling and heat accumulation process. Specifically, reflectivity... Taller objects reflect a greater portion of the incident laser energy, thus reducing the energy absorbed and the instantaneous heat load. The thermal diffusivity... Taller objects transfer heat more quickly and experience slower local temperature rises, making them less prone to reaching the damage threshold due to heat accumulation. Therefore, in this embodiment, to more accurately assess the object's true risk tolerance, the maximum tolerable power derived from a general model is determined based on these attributes. Perform a safety reduction.

[0064] Specifically, this safety reduction is achieved through a correction factor. To achieve this, the revised safe power limit is: The reduction factor From the formula The calculation yields the result. In this formula, and These are two pre-set positive weighting coefficients, used to adjust the relative influence of reflectivity and thermal diffusivity factors in the reduction calculation; It is a reference thermal diffusivity used to normalize the thermal diffusivity of different objects. The formula is designed to... The value of is between 0 and 1. When the object's reflectivity... At lower (i.e., high absorption rate), the item An increase in the value of leads to an increase in the denominator. Decrease; when the thermal diffusivity of the object decreases. At lower levels (i.e., poor heat dissipation), the item Increasing the value of also leads to an increase in the denominator and This means that for objects with low reflectivity (high absorption) or low thermal diffusivity (slow heat dissipation), the allowable safe power limit will be reduced to a greater extent, which is entirely consistent with their physical characteristics of being more susceptible to damage under laser irradiation. By introducing this correction, the technical solution of this embodiment can combine the basic thermal damage parameters of the object material with its surface and interface optical properties and internal heat transfer properties, thereby dynamically generating safe power constraint values ​​that are closer to physical reality and more targeted.

[0065] It should be understood that in the methods described in one or more embodiments of this specification, the order of some steps may be adjusted according to actual needs, or some steps may be omitted.

[0066] Based on the foregoing technical solutions, this invention also provides a laser power adjustment device for remote foreign object removal in power transmission lines, such as... Figure 2 As shown, the device, from a macroscopic perspective, may include the following modules: Image acquisition module 202 is used to acquire real-time images of the laser operation area and form a continuous video stream; The image recognition and classification module 204 is used to identify and classify multiple objects within the area covered by the real-time image based on the real-time image, wherein the multiple objects include at least target foreign objects, wires and insulators; The safety power parameter association module 206 is used to associate a maximum tolerable laser power with each type of identified object based on its material properties. The maximum tolerable laser power is determined based on the material damage energy threshold, the laser irradiation time on the object, and the laser spot area. The local safe power distribution generation module 208 is used to determine a reticle neighborhood region centered on the current laser emission point, and analyze the power tolerance of different objects in the region based on the associated maximum tolerable laser power, so as to form a local safe power distribution for constraining laser power. The maximum safe output power calculation module 210 is used to calculate the maximum safe output power allowed at the current moment based on the current motion direction of the laser, the tracking speed, and the local safe power distribution. The laser power real-time adjustment module 212 is used to dynamically adjust the output power of the laser in real time based on the maximum safe output power.

[0067] Those skilled in the art will understand that the modules in the apparatus of the foregoing embodiments can be distributed in the apparatus of the embodiments as described in the embodiments, or they can be located in one or more devices different from this embodiment with corresponding changes. The modules of the above embodiments can be combined into one module, or they can be further divided into multiple sub-modules, that is, the module division can be flexibly performed to implement the method embodiments described above.

[0068] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for regulating laser power in a remote foreign object removal process for power lines, characterized in that, The method comprises the following steps: collecting real-time images of a laser operation area and forming a continuous video stream; identifying and classifying a plurality of objects in the area covered by the real-time images based on the real-time images, the plurality of objects including at least a target foreign object, a conductor and an insulator; for each identified object, associating a maximum tolerable laser power according to its material properties, wherein the maximum tolerable laser power is determined according to a material damage energy threshold, a laser irradiation time on the object and a laser spot area; determining a crosshair neighborhood area centered on a current laser light emitting point, and analyzing the power tolerance of different objects in the area based on the associated maximum tolerable laser power to form a local safety power distribution for constraining the laser power; calculating a maximum safety output power allowed at the current time according to a current motion direction, a tracking speed of the laser and the local safety power distribution; and real-time dynamically adjusting the light emitting power of the laser based on the maximum safety output power.

2. The method of claim 1, wherein the laser power is adjusted based on the sensed temperature of the transmission line. the maximum tolerable laser power calculated by the following equation: wherein, is the material damage energy threshold, is the laser spot dwell time on the object, is the laser spot area.

3. The method of claim 2, wherein the laser power is adjusted by, The crosshair neighborhood area is determined in one of the following ways: In the image pixel coordinate system, the laser spot pixel coordinates are centered on the pixel coordinates of the laser spot center, the pixel radius of the circular area. In the physical space coordinate system, the spatial position of the laser light emitting point is centered on the center of the laser light emitting point, a spherical region with a radius of 1 meter: 。 4. The method of claim 3, wherein the laser power is adjusted by, The local safety power distribution for constraining the laser power is formed in the following way: constructing a power-constrained distribution function within the field of view of the aiming device : wherein, is the maximum laser power that the i-th object in the vicinity of the aiming point can withstand, is the maximum laser power that the i-th object in the vicinity of the aiming point can withstand, is the maximum laser power that the i-th object in the vicinity of the aiming point can withstand, 5. The method of claim 4, wherein the laser power is adjusted by, The maximum safety output power allowed at the current time is calculated in the following way: According to the current position of the laser , the unit vector of the direction of movement and the tracking speed , the movement path of the laser is predicted for a future prediction time interval : extracting the predicted path through region and the aiming dot neighborhood region the minimum of the maximum tolerable power of all objects inside, calculating the power limit value : Minimum power required to clear a target foreign object , determining a current maximum safe output power : 。 6. The method of claim 5, wherein the laser power is adjusted by, The real-time dynamic adjustment of the light output power of the laser further comprises adjusting the maximum safe output power of the laser based on the following formula : Pmax = P0 + K * (Pmax - P0) : Pmax = P0 + K * (Pmax - P0) wherein is a smoothing coefficient, , is a sampling time interval; wherein the smoothing factor based on the power limit value the proximity to the required power of the clearing wherein, and are the minimum and maximum values of the smoothing coefficient, respectively, is a standard Sigmoid function, is a sensitivity adjustment parameter.

7. The method of claim 6, wherein the laser power is adjusted by, The real-time dynamic adjustment further comprises a constraint step based on a power change rate limit, which comprises: Computing a power adjustment amount ; According to a predetermined maximum rate of power increase and maximum rate of decrease , the final output power is determined according to the following rules : 。 8. The method of claim 5, wherein the laser power is adjusted by, When calculating the power limit value a maximum tolerable power of different objects within the crosshair neighborhood region a maximum tolerable power of different objects within the crosshair neighborhood region a dynamic weight based on spatial distance and relative velocity is applied, and a weighted minimum value calculation is adopted: wherein the weight coefficient is determined by the normalized distance of the object to the current light exit point of the laser and the relative speed of movement of the object with respect to the laser spot, calculated as follows: ; wherein and are characteristic distance constant and characteristic velocity constant, respectively.

9. The method of claim 5, wherein the laser power is adjusted by, the predicted time interval in accordance with the current tracking speed of the laser and the complexity of the environmental target adaptive adjustment is made: wherein, is a reference prediction time, is a reference tracking speed, is a complexity influence coefficient, is an environmental complexity index calculated based on the number of different categories of objects identified in the crosshair neighborhood region and the distribution dispersion thereof.

10. The method of claim 4, wherein the laser power is adjusted during the process of the remote foreign object removal of the power transmission line, and the laser power is adjusted based on the distance between the laser and the foreign object. For an object with known reflectivity and thermal diffusivity its associated maximum tolerable laser power needs to be safety reduced according to its optical and thermal properties to get a revised upper power limit : wherein the reduction factor is calculated from the formula : wherein are positive weight factors, respectively, for adjusting the degree of influence of the reflectivity and the thermal diffusion characteristics, is a reference thermal diffusion coefficient.

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