A method for measuring the centimeter-level positioning of the safety distance of an electrically charged special-purpose vehicle

Abstract

The application relates to the technical field of special operation vehicle safety distance measurement, and discloses a centimeter-level positioning and measurement method for the safety distance of a live body of a special operation vehicle, which comprises the following steps: collecting vehicle body reference coordinates and arm support sensor data, constructing a joint coordinate chain table to recursively solve the spatial coordinates of an end execution mechanism, constructing an arm support space envelope convex polyhedron and calculating the real-time spatial distance from the live body, dynamically adjusting the safety distance threshold value according to the arm support movement rate and comparing and outputting an alarm; the application is coupled with a convex hull through a multi-source sensor chain, eliminates the spatial representation deviation of the single-point positioning of the vehicle body and the dynamic structure of the arm support, ensures the working space at low speed without compression and the time efficiency of high-speed early warning, and realizes centimeter-level positioning and adaptive safety early warning.

Description

Technical Field

[0001] This invention relates to the field of safety distance measurement technology for special operation vehicles, and in particular to a centimeter-level positioning measurement method for the safety distance of live parts of special operation vehicles. Background Technology

[0002] In substation maintenance sites, RTK (Real-Time Kinematic) positioning terminals are typically used to monitor the spatial distance between special operation vehicles and live conductors to ensure the safety of live-line work. This technology obtains the three-dimensional coordinates of the terminal installation point through satellite positioning, combines it with preset live conductor position parameters, calculates the height difference and straight-line distance between the two, and triggers an alarm when the distance is less than a set threshold. Its advantages include high positioning accuracy and fast response speed; however, the measurement results only reflect the spatial position of the fixed point of the positioning terminal itself and cannot directly express the dynamic spatial shape of the vehicle's moving parts.

[0003] In actual operations, when the boom of a crane or other special vehicle performs extension, rotation, or luffing movements, safety warnings often fail to reflect the actual approach of the boom's end to a live conductor. For example, in a substation maintenance scenario, the crane's RTK positioning terminal is fixedly installed on the top of the driver's cab. The system calculates and displays the current distance in real time based on the terminal's coordinates and the preset location of the live conductor. When the crane chassis remains stationary and the boom slowly extends upwards towards the live conductor above, the height difference displayed on the system interface observed by the operator remains unchanged, and there are no alarm prompts. However, it is visible to the naked eye that the metal component at the end of the boom has clearly penetrated into the space below the live conductor, and the gap between them continues to narrow. This delayed warning prevents operators from recognizing the true danger through system feedback, potentially leading them to continue operating the boom deeper into the hazardous area. Once the boom's end intrudes into the safe distance, there is a direct risk of mechanical impact with live equipment or causing a flashover, resulting in equipment damage, circuit breaker tripping, or even personal injury. Therefore, how to solve the problem of inaccurate safety space warnings during the dynamic operation of substation maintenance robotic arms is an urgent problem to be solved in this field. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the present invention aims to provide a centimeter-level positioning measurement method for the safe distance to charged bodies of special operation vehicles. This method uses a BeiDou network RTK positioning terminal with strong magnetic adsorption to collect the vehicle's reference coordinates and simultaneously collect the boom's attitude parameters. Based on the attitude parameters, a joint coordinate chain is constructed to recursively calculate the end-effector position. Furthermore, a spatial envelope convex polyhedron is constructed based on the end-effector position sequence to calculate the real-time distance to the charged body. Simultaneously, the safety threshold is dynamically adjusted according to the movement speed, achieving a safety early warning effect with centimeter-level accuracy.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] In a first aspect, the present invention provides a centimeter-level positioning measurement method for the safe distance of a charged body on a special operation vehicle, comprising: acquiring the vehicle body reference coordinates through a Beidou network RTK positioning terminal strongly magnetically adsorbed onto the vehicle body; simultaneously acquiring the rotation angle value, amplitude angle value, and telescopic joint length value through sensors installed on the boom slewing mechanism, amplitude mechanism, and telescopic mechanism to generate a set of robotic arm posture parameters; based on the set of robotic arm posture parameters, constructing a joint coordinate chain list according to the hinge sequence of each section of the boom and recursively calculating along the chain list to obtain the spatial coordinates of the end effector; arranging the spatial coordinates of the end effector at continuously acquired times to generate a sequence of spatial coordinates of the end effector; constructing a boom spatial envelope convex polyhedron based on the sequence of spatial coordinates of the end effector; calculating the distance between the surface of the boom spatial envelope convex polyhedron and the preset position coordinates of the charged body to obtain a real-time spatial distance value; determining a dynamic safe distance threshold based on the rate of change of the telescopic joint length value and the amplitude angle value in the set of robotic arm posture parameters; comparing the real-time spatial distance value with the dynamic safe distance threshold; and outputting an alarm control command and displaying an alarm status on the screen.

[0007] Preferably, the acquisition of vehicle body reference coordinates includes: receiving satellite carrier phase observation values ​​and differential correction values ​​sent by the reference station through the Beidou network RTK positioning terminal; fusing sensor signals to complete mode switching; and calculating the vehicle body reference coordinates, which include longitude, latitude and geodetic elevation values.

[0008] Preferably, the synchronous acquisition of slewing angle, luffing angle, and telescopic joint length values ​​by sensors installed on the boom slewing mechanism, luffing mechanism, and telescopic mechanism includes: acquiring the slewing angle value by an angle encoder installed on the boom slewing mechanism; acquiring the luffing angle value by an tilt sensor installed on the luffing mechanism; and acquiring the telescopic joint length value by a displacement sensor installed on the telescopic mechanism.

[0009] Further, the generation of the robotic arm posture parameter set includes: aligning the vehicle body reference coordinates, the rotation angle value, the amplitude angle value, and the telescopic joint length value according to their respective acquisition timestamps to generate the robotic arm posture parameter set; wherein, the data structure of the robotic arm posture parameter set is a time sequence arranged according to the calculation time, and each element in the sequence is a quintuple, the quintuple containing the calculation time, the vehicle body reference coordinates, the rotation angle value, the amplitude angle value, and the telescopic joint length value.

[0010] Furthermore, the construction of the joint coordinate linked list includes: using the vehicle body reference coordinates as the coordinates of the first node of the joint coordinate linked list; and determining the projection direction of the bottom section of the boom in the horizontal plane based on the fixed length values ​​of each boom section in the boom structure parameters and in combination with the rotation angle values.

[0011] Furthermore, the step of using the vehicle body reference coordinates as the coordinates of the first node of the joint coordinate chain includes: converting the longitude, latitude, and geodetic elevation values ​​of the vehicle body reference coordinates into geocentric rectangular coordinates using a standard conversion formula; and outputting the coordinates of the first node of the joint coordinate chain after converting the preset station center point of the reference station into station center horizontal rectangular coordinates through translation and rotation, with the preset station center point as the origin.

[0012] Further, the step-by-step recursive calculation along the linked list to obtain the spatial coordinates of the end effector includes: recursively calculating along the joint coordinate linked list, taking the coordinates of the previous node as the starting point for each adjacent node pair in the joint coordinate linked list; determining the direction angle of the spatial displacement component using the amplitude angle value, and determining the magnitude of the spatial displacement component using the telescopic joint length value; converting the spatial displacement component into a three-dimensional coordinate increment and then superimposing it onto the coordinates of the previous node to obtain the coordinates of the current node; repeating the recursive process until the end node of the joint coordinate linked list is reached to obtain the spatial coordinates of the end effector.

[0013] Further, the construction of the boom spatial envelope convex polyhedron includes: extracting the boundary coordinate points of each boom section hinge point during continuous operation from the spatial coordinate sequence of the end effector, and eliminating redundant coordinate points inside; sequentially comparing the relative positional relationship between the spatial coordinates of the end effector and each boundary coordinate point at adjacent acquisition times, and determining whether the current coordinate point is located outside the area enclosed by the existing vertex set; if the current coordinate point is located outside the area enclosed by the existing vertex set, then adding the current coordinate point to the vertex set of the boom spatial envelope convex polyhedron; if it is located inside, discarding the current coordinate point, and obtaining the boom spatial envelope convex polyhedron after processing each point.

[0014] Further, the step of calculating the distance between the surface of the boom spatial envelope convex polyhedron and the preset position coordinates of the charged body to obtain the real-time spatial distance value includes: calculating the vertical distance between each surface of the boom spatial envelope convex polyhedron and the preset position coordinates of the charged body; and selecting the vertical distance with the smallest value from the vertical distances corresponding to each surface as the real-time spatial distance value.

[0015] Further, determining the dynamic safety distance threshold based on the rate of change of the telescopic joint length value and the amplitude angle value in the robotic arm posture parameter group includes: performing a difference operation on the telescopic joint length value and the amplitude angle value at two consecutive acquisition times and dividing by the acquisition time interval to obtain the telescopic speed value and the amplitude angular velocity value; setting a motion rate threshold and a preset basic safety distance; converting the amplitude angular velocity value into an end-effector amplitude linear velocity and then performing an orthogonal vector synthesis with the telescopic speed value to obtain the maximum end-effector linear velocity; when the maximum end-effector linear velocity is greater than the motion rate threshold, calculating an advance compensation amount according to the product relationship between the maximum end-effector linear velocity and the preset basic safety distance, and adding the preset basic safety distance and the advance compensation amount to obtain the dynamic safety distance threshold; when the maximum end-effector linear velocity is less than or equal to the motion rate threshold, directly using the preset basic safety distance as the dynamic safety distance threshold.

[0016] Furthermore, the step of comparing the real-time spatial distance value with the dynamic safety distance threshold and outputting alarm control commands and display alarm status includes: comparing the real-time spatial distance value with the dynamic safety distance threshold; when the real-time spatial distance value is less than the dynamic safety distance threshold, generating an alarm trigger command, controlling the alarm to emit an alarm sound and switching the current distance value on the host display to a red alarm state; when the real-time spatial distance value is greater than or equal to the dynamic safety distance threshold, generating a normal operation mark and maintaining the current display state of the host display.

[0017] Secondly, the present invention provides a centimeter-level positioning and measurement system for the safe distance of charged parts of special operation vehicles. The system includes: a robotic arm posture parameter set generation module, used to collect the vehicle's reference coordinates via a Beidou network RTK positioning terminal strongly magnetically attached to the vehicle body, and simultaneously collect rotation angle values, amplitude angle values, and telescopic joint length values ​​via sensors installed on the boom's slewing mechanism, luffing mechanism, and telescopic mechanism to generate a robotic arm posture parameter set; and an end effector spatial coordinate sequence generation module, used to construct a joint coordinate chain list according to the robotic arm posture parameter set and recursively calculate the spatial coordinates of the end effector section by section along the chain list. The spatial coordinates of the end effector at any given time are arranged to generate a spatial coordinate sequence of the end effector; the real-time spatial distance value calculation module is used to construct a boom spatial envelope convex polyhedron based on the spatial coordinate sequence of the end effector, calculate the distance between the surface of the boom spatial envelope convex polyhedron and the position coordinates of the preset charged body, and obtain the real-time spatial distance value; the dynamic safety distance threshold determination and alarm module is used to determine the dynamic safety distance threshold based on the rate of change of the telescopic joint length value and the amplitude angle value in the robotic arm posture parameter group, compare the real-time spatial distance value with the dynamic safety distance threshold, and output alarm control commands and alarm status on the display screen.

[0018] Compared to existing technologies, the advantages of this invention are as follows: By constructing a set of robotic arm posture parameters, this invention aligns the vehicle body reference coordinates with the rotation angle, amplitude angle, and telescopic joint length values ​​according to a unified time reference, and recursively calculates the spatial coordinate sequence of the end effector along the joint coordinate chain. This achieves spatial geometric mapping between the fixed-installation RTK positioning terminal and the multi-degree-of-freedom boom dynamic structure, eliminating the representational deviation at the physical level where the single-point coordinates of the vehicle body cannot reflect the actual spatial position of the end effector. The boom spatial envelope convex polyhedron constructed based on the end effector spatial coordinate sequence uses the envelope surface of continuous motion trajectories instead of a single instantaneous point as the distance calculation object, covering the space swept by the boom within the sampling interval and avoiding missed detection of end effector intrusions. Furthermore, the dynamic safety distance threshold is determined based on the rate of change of the telescopic joint length and amplitude angle values. During high-speed boom movement, the safety judgment boundary is adaptively expanded to ensure timely warnings; during low-speed fine-tuning, the threshold reverts to the base value to retain operable space, resolving the contradiction between warning lag and limited space under a fixed threshold. This invention forms a closed loop from multi-source synchronous calculation and spatial envelope to threshold adaptation, providing an accurate safety distance measurement and alarm scheme for special vehicles with moving mechanisms. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a flowchart of a centimeter-level positioning method for the safe distance of a live conductor on a special operation vehicle, as described in this invention.

[0021] Figure 2 This is a schematic diagram of the system hardware and sensor deployment in an embodiment of the present invention;

[0022] Figure 3 This is a schematic diagram of the robotic arm posture parameter group in an embodiment of the present invention;

[0023] Figure 4 This is a schematic diagram of the station-center horizontal rectangular coordinate system in an embodiment of the present invention;

[0024] Figure 5 This is a schematic diagram of the joint coordinate chain list being recursively deduced in an embodiment of the present invention;

[0025] Figure 6 This is a schematic diagram of chord height deviation encryption in an embodiment of the present invention;

[0026] Figure 7 This is a schematic diagram of the construction of the boom space envelope convex polyhedron in an embodiment of the present invention;

[0027] Figure 8 This is a schematic diagram illustrating the calculation of real-time spatial distance values ​​in an embodiment of the present invention;

[0028] Figure 9 This is a schematic diagram of the dynamic safety distance threshold in an embodiment of the present invention;

[0029] Figure 10 This is a functional block diagram of a centimeter-level positioning system for the safe distance of charged parts of special operation vehicles in this invention. Detailed Implementation

[0030] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] Example 1:

[0032] Please see Figure 1 As shown, this embodiment provides a centimeter-level method for determining the safe distance to live conductors of special operation vehicles, including:

[0033] This embodiment uses crane operation at a 220kV substation maintenance site as a specific application scenario. The crane includes a vehicle body, a boom slewing mechanism mounted on the vehicle body, a boom luffing mechanism connected to the boom slewing mechanism, and a boom telescopic mechanism arranged along the boom axis. A hook, serving as the end effector, is installed at the end of the boom. During substation maintenance, the crane chassis remains stationary, while the boom can rotate, luff, and telescopically move in three-dimensional space under the drive of the boom slewing mechanism, boom luffing mechanism, and boom telescopic mechanism, causing the spatial position of the end effector to continuously change. The system hardware includes: a Beidou network RTK positioning terminal mounted on the top of the vehicle cab via a strong magnetic adsorption base; an angle encoder mounted on the boom slewing mechanism; an angle sensor mounted on the boom luffing mechanism; a displacement sensor mounted on the boom telescopic joint; a base station host that presets the position coordinates and safety distance of charged bodies and performs calculations; an alarm; and a host display screen. The station-center horizontal rectangular coordinate system described in this embodiment refers to a right-hand rectangular coordinate system with the preset station center point of the base station as the origin, the X-axis pointing due east, the Y-axis pointing due north, and the Z-axis pointing towards the zenith.

[0034] S1: The Beidou network RTK positioning terminal, which is strongly magnetically attached to the vehicle body, collects the vehicle body's reference coordinates. Simultaneously, the sensors installed on the boom slewing mechanism, luffing mechanism, and telescopic mechanism collect the slewing angle value, luffing angle value, and telescopic joint length value to generate a set of robotic arm posture parameters.

[0035] In substation maintenance operations, where the crane chassis is stationary while the boom moves with multiple degrees of freedom, the three-dimensional coordinates of the fixed installation point of the BeiDou network RTK positioning terminal alone cannot reflect the actual spatial position of the end effector. To reconstruct the true spatial coordinates of the end effector in subsequent steps, this step requires simultaneously acquiring the sensor outputs representing the boom's rotation, luffing, and telescopic motion states while collecting the vehicle's reference coordinates. The vehicle's single-point positioning data and the boom's multi-degree-of-freedom sensor outputs are then grouped together according to a unified time reference to form a robotic arm attitude parameter set, providing a physical layer synchronous input for subsequent coordinate calculations. This robotic arm attitude parameter set refers to a sequence of time-series parameters organized by aligning the vehicle's reference coordinates with the rotation angle, luffing angle, and telescopic joint length values ​​at the same calculation time.

[0036] Further, step S1 includes:

[0037] S11: Receives satellite carrier phase observations and differential corrections from the base station via the BeiDou network RTK positioning terminal, fuses sensor signals to complete mode switching, and calculates the vehicle's reference coordinates, which include longitude, latitude, and geodetic elevation.

[0038] Substations contain a large number of metal structures and electrical equipment, and satellite signals are susceptible to blockage and multipath interference, resulting in short-term loss of lock. If only satellite observations are used for calculation, the vehicle reference coordinates will jump or be missing during the signal loss period, which cannot meet the centimeter-level continuous positioning requirements. Therefore, this step adopts a calculation method that fuses satellite carrier phase observations with inertial measurement unit signals.

[0039] Specifically, the BeiDou network RTK positioning terminal receives carrier phase observations from BeiDou satellites via an antenna, and simultaneously receives differential correction values ​​from the base station via a network data link. These differential correction values ​​are carrier phase error corrections calculated by the base station based on its known coordinates and synchronous satellite observations.

[0040] The Beidou network RTK positioning terminal has a built-in inertial measurement unit, which includes a three-axis accelerometer and a three-axis gyroscope, and outputs the vehicle's three-axis acceleration and three-axis angular velocity.

[0041] The fusion processing employs an extended Kalman filter, using the position calculated from the carrier phase differential as the observation and the position calculated from the integral of acceleration and angular velocity output by the inertial measurement unit as the state prediction. The two are weighted and fused in the extended Kalman filter, which accelerates the convergence of the Kalman filter for integer ambiguity and completes the switch from pseudorange single-point positioning mode to carrier phase differential fixed solution mode, enabling the positioning system to enter a centimeter-level high-precision mode within one minute.

[0042] The criteria for determining the completion of mode switching are: the differential status field in the $GNGGA positioning data message output by the Beidou network RTK positioning terminal according to the NMEA0183 standard protocol is 4, which means the carrier phase differential fixed solution status.

[0043] The solution outputs the vehicle body reference coordinates, which include longitude, latitude, and geodetic elevation values, referencing the CGCS2000 geodetic coordinate system. For example, the vehicle body reference coordinates are longitude 116.35000 degrees, latitude 39.90000 degrees, and geodetic elevation 53.000 meters.

[0044] S12: The slewing angle value is collected by the angle encoder installed on the boom slewing mechanism, the luffing angle value is collected by the tilt sensor installed on the boom luffing mechanism, and the length value of the telescopic joint is collected by the displacement sensor installed on the boom telescopic joint.

[0045] The subsequent step S2 requires the rotation angle, amplitude angle and telescopic joint length as quantization inputs for the motion state of each degree of freedom of the boom to complete the coordinate recursion. However, the Beidou network RTK positioning terminal can only provide the coordinates of the fixed installation point on the vehicle body and cannot sense the attitude change of the boom relative to the vehicle body. Therefore, this step deploys corresponding sensors on the three motion mechanisms of the boom to quantize the motion of the three degrees of freedom of the boom into values ​​that can be calculated.

[0046] Specifically, the angle encoder is installed at the slewing bearing of the boom slewing mechanism to collect the slewing angle value. The slewing angle value is defined as the angle between the boom's unfolded orientation in the horizontal plane and the due north direction, with due north as 0 degrees and clockwise as positive. The value range is from 0 degrees to 360 degrees. The angle encoder is an absolute encoder with a resolution of 0.01 degrees.

[0047] The tilt sensor is installed at the base of the boom of the boom luffing mechanism to collect the luffing angle value. The luffing angle value is defined as the elevation angle between the boom axis and the horizontal plane, and the value ranges from 0 degrees to 90 degrees. The tilt sensor has a resolution of 0.01 degrees.

[0048] A displacement sensor is installed on the boom telescopic joint to collect the joint length value. The telescopic joint length value is defined as the total length of the telescopic boom joint after it has actually extended relative to the basic boom joint. The displacement sensor is a wire-type displacement sensor with a resolution of 1 mm. See also Figure 2 This is a schematic diagram of the system hardware and sensor deployment provided in an embodiment of this application. Figure 2 As shown, a cab is mounted on the crane body, and a Beidou network RTK positioning terminal is fixed to the top of the cab via a strong magnetic adsorption base. An angle encoder is installed at the boom slewing mechanism, an inclination sensor is installed at the boom luffing mechanism, and a displacement sensor is installed at the boom telescopic joint. A hook, serving as the end effector, is installed at the end of the boom. The diagram illustrates that the Beidou network RTK positioning terminal can only provide the coordinates of the fixed mounting point on the crane body. The angle encoder, inclination sensor, and displacement sensor respectively collect the slewing angle, luffing angle, and telescopic joint length values, quantifying the motion states of the boom's three degrees of freedom (slewing, luffing, and telescopic) into calculable values. These are collected synchronously at the physical level, providing the hardware foundation for subsequently merging the single-point positioning data of the crane body and the outputs of the boom's multi-degree-of-freedom sensors into a unified time reference for the robotic arm's attitude parameter group. This allows the spatial positional changes of the end effector to be characterized.

[0049] The angle encoder, tilt sensor, and displacement sensor are each appended with a system clock timestamp during each sampling. The system clock is calibrated by the second pulse signal output by the BeiDou network RTK positioning terminal. For example, at a certain sampling moment, the rotation angle is 0.00 degrees, the amplitude angle is 60.00 degrees, and the expansion joint length is 7.125 meters.

[0050] S13: Align the vehicle body reference coordinates, rotation angle value, amplitude angle value, and telescopic joint length value according to their respective collection timestamps to generate a set of robotic arm posture parameters.

[0051] The vehicle body reference coordinates are output by the Beidou network RTK positioning terminal at a fixed sampling frequency. The rotation angle value, amplitude angle value, and telescopic joint length value are output by three types of sensors at their own independent sampling frequencies. The sampling times of the four types of data do not overlap. If the four types of data are not time-aligned and directly substituted into the coordinate calculation, the vehicle body position and boom attitude used in the same calculation will belong to different physical times, resulting in a misalignment of the spatial coordinates of the end effector that is proportional to the sampling time difference.

[0052] Specifically, the UTC time field in the $GNGGA positioning data message output by the BeiDou network RTK positioning terminal is used as the master clock reference.

[0053] The system clock timestamps attached to the data collected by each sensor are synchronized with UTC time via the second pulse signal of the BeiDou network RTK positioning terminal, with a synchronization error of less than 1 millisecond.

[0054] A unified solution time sequence is set, with the time when the vehicle body reference coordinates are output by the Beidou network RTK positioning terminal as the node.

[0055] For each solution time in the unified solution time sequence, the slewing angle value, amplitude angle value, and expansion joint length value are aligned to that solution time through linear interpolation. The linear interpolation method is as follows: take the collection values ​​and collection timestamps of two adjacent sensor sampling points before and after the solution time, and linearly weight the two collection values ​​according to the time ratio of the solution time to the two collection timestamps before and after, to obtain the slewing angle value, amplitude angle value, and expansion joint length value corresponding to the solution time.

[0056] Generate the robotic arm attitude parameter set. The data structure of the robotic arm attitude parameter set is a time sequence arranged according to the calculation time. Each element in the sequence is a quintuple, which contains the calculation time, vehicle reference coordinates, rotation angle value, amplitude angle value, and telescopic joint length value. See also Figure 3 This is a schematic diagram of the robotic arm posture parameter group provided in an embodiment of this application. For example... Figure 3As shown, the vehicle body reference coordinates, rotation angle value, amplitude angle value, and telescopic joint length value are collected along their respective time axes at independent sampling frequencies. The original sampling points on the four time axes are aligned to each solution time node in the unified solution time sequence through linear interpolation, and finally organized into a data frame of robotic arm posture parameters. The data frame is arranged according to the solution time, vehicle body reference coordinates, rotation angle value, amplitude angle value, and telescopic joint length value. This figure illustrates the process of merging the vehicle body single-point positioning data and the output of the boom multi-degree-of-freedom sensors according to a unified time reference, so that each input quantity participating in the same recursive solution corresponds to the true posture of the boom at the same solution time, eliminating the misalignment components introduced into the spatial coordinates of the end effector due to the non-overlapping of multi-source sampling times from the data source.

[0057] The robotic arm posture parameter group unifies the single-point positioning coordinates of the vehicle body and the output quantities of the boom's three-degree-of-freedom sensors to the same calculation time. This ensures that the vehicle body reference coordinates, rotation angle values, luffing angle values, and telescopic joint length values ​​substituted into the recursive calculation in S2 correspond to the actual boom posture at the same physical moment. Under the working conditions of rapid boom luffing or telescopic movement, the product of the original sampling time difference of the four types of data and the linear velocity of the boom end effector constitutes the misalignment of the spatial coordinates of the end effector. For every deviation of the sampling time difference from one sampling cycle, the spatial coordinates of the end effector will shift along the direction of motion proportional to the linear velocity of the boom end effector. After aligning with the UTC time reference and the second pulse signal, the physical time difference of each input quantity participating in the same recursive calculation is compressed to within the second pulse synchronization error range. This eliminates the misalignment component introduced into the spatial coordinates of the end effector due to the non-overlapping sampling times of multiple sources from the data source, ensuring the consistency of the boom posture on the time axis based on the S2 recursive calculation.

[0058] S2: Based on the robotic arm posture parameter set, construct a joint coordinate chain list according to the hinge sequence of each section of the arm and recursively calculate along the chain list to obtain the spatial coordinates of the end effector. Arrange the spatial coordinates of the end effector at continuously collected times to generate a spatial coordinate sequence of the end effector.

[0059] In the robotic arm attitude parameter set output in the preceding step S1, the vehicle body reference coordinates only represent the position of the fixed installation point of the Beidou network RTK positioning terminal, while the rotation angle, luffing angle, and telescopic joint length values ​​only represent the motion state of each mechanism of the boom. These two types of information have not yet been established in spatial geometry. If the vehicle body reference coordinates are directly used as the basis for calculating the distance between the crane and the live conductor, the vehicle body reference coordinates will remain unchanged during boom extension, rotation, or luffing, failing to reflect the actual process of the end effector approaching the live conductor, resulting in a failure where the distance value remains unchanged but the end effector has already exceeded its limits. This step constructs a joint coordinate linked list and recursively calculates along the linked list section by section, coupling the single-point coordinates of the vehicle body with the multi-degree-of-freedom attitude of the boom into the true spatial coordinates of the end effector. The joint coordinate linked list refers to an ordered sequence of nodes arranged sequentially from the root to the end of the boom, with each boom section's hinge point as a node and the boom segments between adjacent hinge points as links.

[0060] Further, step S2 includes:

[0061] S21: Using the vehicle body reference coordinates as the coordinates of the first node of the joint coordinate chain, determine the projection direction of the bottom section of the boom in the horizontal plane based on the fixed length values ​​of each boom section in the boom structure parameters and the rotation angle values.

[0062] In the robotic arm attitude parameter set output in the preceding step S13, the vehicle reference coordinates are represented by longitude, latitude, and geodetic elevation values. These are geodetic coordinates, and the dimensions of each component are inconsistent, making direct three-dimensional vector superposition impossible. To ensure that the subsequent recursive coordinate increments can be accumulated in rectangular coordinates, this step must first convert the vehicle reference coordinates into station-centered horizontal rectangular coordinates as the coordinates of the first node in the joint coordinate chain list, and determine the deployment direction of the boom in the horizontal plane based on the rotation angle value.

[0063] Specifically, the coordinate transformation process is as follows: the longitude, latitude, and geodetic elevation values ​​of the vehicle's reference coordinates are first converted to geodetic rectangular coordinates using the standard conversion formula from geodetic coordinates to geocentric rectangular coordinates. Then, using the preset station center point as the origin, the values ​​are converted to station-centered geodetic rectangular coordinates through translation and rotation. Finally, the coordinates of the first node of the joint coordinate chain list are output. ,in, This represents the eastward offset component of the vehicle's reference coordinates relative to the station center point. This represents the offset component of the vehicle's reference coordinates relative to the station center point in the due north direction. This represents the component of the geodetic elevation relative to the station center in the zenith direction. For example, the vehicle body reference coordinates are transformed to obtain the coordinates of the first node of the joint coordinate chain list. The unit is meters.

[0064] The boom structure parameters include the fixed length values ​​of each boom section. These fixed length values ​​are obtained by measuring the physical length of each boom section with a steel tape measure during system installation and stored in the base station. For example, the boom consists of two sections: a basic boom section and a telescopic boom section. The fixed length value of the basic boom section... rice.

[0065] The structural offset vector is a fixed three-dimensional offset of the boom rotation center relative to the installation point of the BeiDou network RTK positioning terminal. It is obtained by measuring the relative position between the center of the strong magnetic adsorption base on the vehicle body and the center of the slewing bearing during system installation, and is denoted as . For example, the structure offset vector is The unit is meters, from which the coordinates of the center node of rotation are obtained. .

[0066] The projection direction of the boom bottom section in the horizontal plane is determined by the rotation angle value. It is determined that the projection direction is the unit direction vector within the horizontal plane. For example, the rotation angle value. Projection direction in degrees That is, the boom extends in a due north direction. See also Figure 4 This is a schematic diagram of the station-center horizontal rectangular coordinate system provided in the embodiments of this application. For example... Figure 4 As shown, the coordinate system has its origin at the preset center point of the base station, with the X-axis pointing due east, the Y-axis pointing due north, and the Z-axis pointing towards the zenith. The figure marks the coordinates of the first node of the joint coordinate chain and the projection direction determined by the rotation angle value. The projection direction is a unit direction vector in the horizontal plane, and the included arc corresponding to the rotation angle value is also shown. This figure demonstrates how the coordinates of the first node of the joint coordinate chain are obtained by converting the vehicle's reference coordinates to geodetic coordinates, then to geocentric rectangular coordinates, and finally to station-centered horizontal rectangular coordinates. The deployment direction of the boom bottom section in the horizontal plane is determined based on the rotation angle value, allowing the vehicle's single-point positioning coordinates and the output of the boom attitude sensor to be vector-superimposed in the same rectangular coordinate system, providing a unified coordinate system reference for the recursive progression of each section.

[0067] S22: Proceed recursively along the joint coordinate chain, substituting the amplitude angle value and the expansion joint length value into the calculation of the spatial displacement components of the adjacent nodes, and accumulating the spatial displacement components to the coordinates of the previous node to obtain the coordinates of the current node.

[0068] In the joint coordinate chain, the spatial orientation of boom segments between adjacent nodes is determined by the amplitude angle value, and the segment length is determined by the fixed length value of each boom segment and the length value of the telescopic joint. Since the position of the end effector is the sum of the vectors of each boom segment, any change in the direction or length of any segment will be transmitted to the end effector. Therefore, this step must proceed recursively from the root node to the end node along the joint coordinate chain, accumulating the spatial displacement components of each segment sequentially.

[0069] Specifically, step S22 includes: for each pair of adjacent nodes in the joint coordinate chain, starting from the coordinates of the previous node, determining the direction angle of the spatial displacement component using the amplitude angle value, determining the modulus of the spatial displacement component using the length of the expansion joint, converting the direction angle and modulus into three-dimensional coordinate increments and then superimposing them onto the coordinates of the previous node to obtain the coordinates of the current node.

[0070] For the first boom segment, segment length The elevation angle of this boom section is determined by its fixed length, while for telescopic boom sections it is determined by the telescopic section length; the elevation angle of this section is determined by its amplitude angle. It is determined that the horizontal orientation is determined by the projection direction defined by S21. The three-dimensional coordinate increments of the spatial displacement components are:

[0071]

[0072] Current node coordinates are See also Figure 5 This is a schematic diagram illustrating the step-by-step recursion of the joint coordinate chain provided in the embodiments of this application. For example... Figure 5 As shown, starting from the coordinates of the previous node, the boom segment extends to the current node coordinates. The segment length and amplitude angle determine the elevation angle and modulus of the boom segment. The projection components of the segment length in the horizontal and zenith directions together constitute the spatial displacement component. This figure illustrates a recursive method where the amplitude angle determines the direction angle of the spatial displacement component, the segment length determines the modulus of the spatial displacement component, and the direction angle and modulus are converted into three-dimensional coordinate increments and superimposed on the coordinates of the previous node to obtain the coordinates of the current node. This makes the position of the end effector the cumulative result of the vectors of each boom segment. Any change in the direction or length of any segment is transmitted to the end effector, realizing a recursive coordinate coupling from the root node to the end node.

[0073] The design principle of the above three-dimensional coordinate increment expression is as follows: This is the projection factor of the boom segment length in the horizontal plane. The projection factor of the boom segment length in the zenith direction is the sum of the two factors for the segment modulus. The amplitude angle value is decomposed into horizontal and vertical components; and The horizontal component is further decomposed into east and north directions based on the rotation angle value. (Amplitude angle value) When it increases Increase The reduction corresponds to the physical law that the boom's end rises vertically while its horizontal extension is shorter during lifting. For a straight boom telescopic crane with the same luffing angle in each section, each section... Use the same luffing angle value; for folding boom trucks with different luffing angle values ​​for each section, each section... The luffing angle value of the corresponding section is taken respectively, and the recursive expression is uniformly applicable to both types of boom structures.

[0074] For example, rotation angle value Degree, basic boom segment fixed length value Meters, amplitude angle value At degree, the spatial displacement component of the first boom segment is , rice, Meters, accumulated to the coordinates of the center node of rotation. Obtain the coordinates of the hinge point at the end of the first boom section. .

[0075] Then, by recursively applying this formula to the telescopic boom section, the length value of the telescopic boom section is obtained. Meters, amplitude angle value At degree, the spatial displacement component of the second boom segment is , rice, Meters, accumulated to the coordinates of the hinge point at the end of the first boom section. Obtain the coordinates of the end node of the second boom section. .

[0076] S23: Repeat step S22 until the end node of the joint coordinate chain is reached to obtain the spatial coordinates of the end effector; arrange the spatial coordinates of the end effector corresponding to multiple acquisition times in chronological order to generate the spatial coordinate sequence of the end effector.

[0077] The recursive processing in step S22 targets a single pair of adjacent nodes in the joint coordinate chain. However, the boom is composed of multiple boom segments connected in series, so the recursive processing needs to be extended to the last node to obtain the spatial coordinates of the end effector. At the same time, the subsequent step S3 must use the spatial occupancy range during continuous motion as the distance calculation object. The spatial coordinates of the end effector at a single acquisition moment cannot reflect the boom motion trajectory. Therefore, after completing the recursive processing at the last node, this step further organizes the spatial coordinates of the end effector at multiple acquisition moments into a sequence in chronological order.

[0078] Specifically, starting from the coordinates of the rotation center node, the recursive processing of step S22 is repeated. Each time, the current node coordinate obtained is used as the coordinate of the previous node in the next recursion, until the end node of the joint coordinate chain is reached. The coordinates of the end node are then used as the spatial coordinates of the end effector. For example, the second boom section is the end section, and the spatial coordinates of the end effector are the coordinates of the end node. The unit is meters, meaning the end effector is currently located at a height of 13.000 meters in the zenith direction of the station's center-of-ground rectangular coordinate system.

[0079] The above recursive process is repeated for each solution time in the timing sequence of the robotic arm's attitude parameters to obtain the spatial coordinates of the end effector corresponding to each solution time. These spatial coordinates are then arranged chronologically to generate a sequence of end effector spatial coordinates. The data structure of the end effector spatial coordinate sequence is an ordered sequence arranged chronologically by solution time. Each element in the sequence is a tuple containing the solution time and the corresponding spatial coordinates of the end effector. For example, the sequence of end effector spatial coordinates corresponding to three consecutive solution times is as follows: Solution Time correspond Solution time correspond Solution time correspond The unit is meters, which reflects the continuous luffing and extension of the boom accompanied by slight rotation during the continuous calculation time.

[0080] The coordinate recursion link in this step links the absolute coordinates of a single point on the vehicle body output by the BeiDou network RTK positioning terminal with the relative attitude values ​​of the boom output by the angle encoder, tilt sensor, and displacement sensor on the joint coordinate chain. Both types of information sources are indispensable in the calculation of the spatial coordinates of the end effector. The vehicle body reference coordinates provided by the BeiDou network RTK positioning terminal determine the absolute position of the first node coordinate of the joint coordinate chain in the station-centered geocentric rectangular coordinate system, but do not contain any geometric information of the boom relative to the vehicle body. The rotation angle value, amplitude angle value, and telescopic joint length value provided by the angle encoder, tilt sensor, and displacement sensor determine the spatial displacement components of each boom segment relative to the previous node, but these are all relative quantities. Without the coordinates of the first node of the joint coordinate chain, the boom cannot be positioned in the station-centered geocentric rectangular coordinate system. If only the vehicle body reference coordinates are available but the boom's three-degree-of-freedom sensor outputs are missing, the segment-by-segment recursion cannot be initiated, and the solution degenerates into the coordinates of the vehicle body's fixed mounting point, resulting in a failure mode where the boom extends but the distance remains unchanged. If only the boom's three-degree-of-freedom sensor outputs are available but the vehicle body reference coordinates are missing, the spatial displacement components of each boom segment lack an absolute reference origin, making it impossible to compare them with the preset charged body position coordinates in the same coordinate system. The end effector spatial coordinates obtained by the segment-by-segment recursion coupling of these two types of information sources through the joint coordinate linked list are mathematically inseparable from the output of any single information source. Absolute positioning capability and relative attitude perception capability are nested within each other in the recursive expression; the absence of either one renders the end effector spatial coordinates meaningless. Furthermore, the joint coordinate linked list expresses the boom structure using a general formula of the number of nodes and the spatial displacement components of adjacent nodes. This general formula for segment-by-segment recursion does not depend on the specific number of boom segments. For telescopic or folding booms with different numbers of segments, only the number of nodes in the joint coordinate linked list and the source of each segment's amplitude angle value need to be adjusted to reuse the same recursive logic. The spatial coordinate sequence of the end effector output in this step provides a set of candidate vertices covering the continuous motion trajectory for S3 to construct the boom spatial envelope convex polyhedron. The coupling accuracy of the two types of information sources directly determines the positional accuracy of the vertices of the convex polyhedron in the station-centered geocentric Cartesian coordinate system.

[0081] In this embodiment, the hoisting rope length between the boom end section hinge point and the end effector (hook) remains relatively fixed during maintenance operations, or its variation is much less than the accuracy required for determining the safe distance. Therefore, the coordinates of the boom end section hinge point are approximated as the spatial coordinates of the end effector. For operation scenarios where the real-time variation of the hoisting rope length has a significant impact, an additional node with the hoisting rope length as the displacement component and the direction vertically downward can be added to the end of the joint coordinate chain. The recursive method described in S22 is reused to calculate the spatial coordinates of the end effector. This extension does not change the structure of the recursive formula in S22, and the remaining steps remain unchanged.

[0082] S3: Construct a boom spatial envelope convex polyhedron based on the spatial coordinate sequence of the end effector, calculate the distance between the surface of the boom spatial envelope convex polyhedron and the preset position coordinates of the charged body, and obtain the real-time spatial distance value.

[0083] The spatial coordinate sequence of the end effector output in step S23 is composed of coordinate points at discrete solution times. There is a sampling interval between two adjacent solution times. If only the spatial coordinates of the end effector at a single solution time are used as the distance calculation object, the space occupied by the instantaneous movement of the boom within the sampling interval will not be represented, and there may be missed detections where the end effector instantaneously intrudes into the safety range of a live conductor within the sampling interval. This step condenses the spatial coordinate sequence of the end effector into a spatially occupied region, using the surface of the region rather than a single point as the distance calculation object. The boom spatial envelope convex polyhedron refers to the smallest convex polyhedron formed by taking the convex hull of the spatial coordinate point set formed by the coordinates of the hinge points of each boom section and the spatial coordinates of the end effector during continuous movement. The boom spatial envelope convex polyhedron completely encompasses the space swept and occupied by the boom during the continuous movement period under the condition of chord height deviation encryption described in S311.

[0084] Further, step S3 includes:

[0085] S31: Extract the boundary coordinates of each articulation point of the boom section during continuous motion from the spatial coordinate sequence of the end effector, remove redundant coordinates inside, and construct the vertex set of the boom spatial envelope convex polyhedron.

[0086] The spatial coordinate sequence of the end effector and the set of spatial coordinate points formed by the articulation points of each boom section during continuous operation contain a large number of coordinate points located within the occupied spatial area. These internal coordinate points do not constitute the boundary of the occupied spatial area. Retaining all of them would increase the computational workload of subsequent convex polyhedron surface distance calculations without changing the distance results. This step requires selecting the coordinate points located at the boundary from the set of spatial coordinate points as vertices of the boom's spatial envelope convex polyhedron, and eliminating redundant internal coordinate points, thereby using as few vertices as possible to completely represent the boundary of the boom's occupied spatial area.

[0087] Further, step S31 includes:

[0088] S311: Compare the relative positional relationship between the spatial coordinates of the end effector and the coordinates of the hinge points of each section of the boom at adjacent acquisition times, and determine whether the current coordinate point is located outside the area enclosed by the existing set of vertices.

[0089] The construction of the boom's spatial envelope convex polyhedron adopts a point-by-point incremental approach. For each coordinate point to be determined, its positional relationship relative to the existing vertex set within the convex polyhedron must be assessed before deciding whether to include it in the vertex set. This step involves determining whether each coordinate point to be determined is located outside the area enclosed by the existing vertex set, based on the spatial coordinate sequence of the end effector and the coordinates of each hinge point of the boom section.

[0090] Specifically, the coordinates of the hinge points of each section of the boom are the coordinates of each intermediate node obtained in the step-by-step recursion process of step S22, together with the spatial coordinates of the end effector, forming a set of hinge point coordinates at each solution time; the hinge point coordinates corresponding to all solution times of the end effector spatial coordinate sequence are collected into a set of coordinate points to be determined.

[0091] To ensure that the set of coordinate points to be determined can sufficiently approximate the actual sweep trajectory of the boom's continuous movement, in cases where the deviation of the arc chord height exceeds a preset chord height threshold (preferably 5 mm) due to a large rotational or amplitude-changing angular velocity between two adjacent calculation moments, following the same recursive method described in S22, the rotational angle value, amplitude-changing angle value, and telescopic joint length value are interpolated between two adjacent calculation moments to generate one or more intermediate moments' coordinates of the boom's hinge points. These coordinates are then included in the set of coordinate points to be determined, and subsequent point-by-point judgment and convex hull construction are performed. This ensures that the candidate point set upon which the convex hull construction is based can cover the actual trajectory range of the arc motion convex outward relative to the chord line. See also Figure 6 This is a schematic diagram of chord height deviation encryption provided in an embodiment of this application. Figure 6 As shown, the spatial coordinates of the end effector at two adjacent solution moments are represented by solid endpoints. The actual motion trajectory between them is an arc. There is a chord height deviation between the arc and the chord connecting the two endpoints. Hollow dots mark the intermediate moment coordinate points to be determined due to the chord height deviation exceeding the preset chord height threshold. This figure illustrates the situation where the arc chord height deviation exceeds the preset chord height threshold due to a large rotational or amplitude angular velocity between two adjacent solution moments. The coordinates of the hinge points of each section of the boom at the intermediate moment are interpolated using the same recursive method and included in the set of coordinate points to be determined. This ensures that the candidate point set on which the convex hull structure is based can cover the actual trajectory range of the arc motion convex outward relative to the chord.

[0092] Initialize the existing vertex set: Select four non-coplanar coordinate points from the set of coordinate points to be determined to form an initial tetrahedron as the existing vertex set. In order to avoid the hinge points of the boom being approximately collinear at a single solution time, the four coordinate points are taken from different solution times to ensure that the four coordinate points are not coplanar.

[0093] For each triangular surface of a convex polyhedron bounded by the existing set of vertices, determine the plane equation using the three vertices of that surface. normal vector Normalize and take the direction pointing to the outside of the convex polyhedron as the positive direction.

[0094] Substitute the coordinates of the point to be determined into the equations of each surface plane, and calculate the signed distance of the point to be determined relative to each surface. The signed distance is equal to the value obtained by substituting the coordinates of the point to be determined into the left-hand side of the normalized plane equation. The determination rule is as follows: if the signed distance of the point to be determined relative to at least one surface is greater than 0, that is, the point to be determined is located outside the surface, then the point to be determined is determined to be located outside the region enclosed by the existing set of vertices; if the signed distance of the point to be determined relative to all surfaces is less than or equal to 0, then the point to be determined is determined to be located inside the region enclosed by the existing set of vertices.

[0095] For example, suppose a certain triangular surface of a convex polyhedron bounded by an existing set of vertices is formed by the vertices... , , It is confirmed that the x-coordinates of the three vertices are all 10.000, and the corresponding plane equation is: The interior of the convex polyhedron lies on the side with an x-coordinate less than 10.000, therefore the unit outward normal vector of this surface is... Coordinates to be determined Substituting the values, we get the signed distance as If the value is greater than 0, determine the coordinates of the point to be determined. Located outside the region enclosed by the existing set of vertices; coordinates to be determined Substituting the values, we get the signed distance as: If the distance is less than 0, the point is located inside the surface and must be compared with other surfaces. If the distance to the sign of all surfaces is less than or equal to 0, then the coordinate point to be determined is determined. It is located inside the area enclosed by the existing set of vertices.

[0096] S312: If the current coordinate point is located outside the region enclosed by the existing vertex set, add the current coordinate point to the vertex set of the boom space envelope convex polyhedron; if it is located inside, discard the current coordinate point, and after processing each point, obtain the boom space envelope convex polyhedron.

[0097] The positional relationship determination result output in step S311 needs to be transformed into an actual update operation on the vertex set in order to gradually expand the convex polyhedron of the boom space envelope. Therefore, this step determines whether to include the coordinate point to be determined in the vertex set or discard it based on the determination result of the inner and outer sides of the region enclosed by the existing vertex set relative to the coordinate point to be determined.

[0098] Specifically, if the coordinate point to be determined is located outside the region enclosed by the existing vertex set, then the coordinate point to be determined is added to the vertex set, all visible surfaces on the existing convex polyhedron with a sign distance greater than 0 from the coordinate point to be determined are deleted, and several new triangular surfaces are reconstructed using the coordinate point to be determined as the vertex and the boundary edges of the deleted visible surfaces as the bases. The vertex set and surface set of the convex polyhedron are then updated. See also... Figure 7 This is a schematic diagram of the construction of the boom spatial envelope convex polyhedron provided in an embodiment of this application. For example... Figure 7 As shown, the region enclosed by the existing vertex set consists of a mesh outline formed by several triangular surfaces. The figure shows that coordinate points to be determined located inside this region are marked as discarded, and coordinate points to be determined located outside this region are connected to the deleted visible triangular surfaces by dashed lines to represent the reconstruction process. This figure illustrates that if the coordinate point to be determined is located outside the region enclosed by the existing vertex set, it is added to the vertex set, all visible surfaces on the existing convex polyhedron with a signed distance greater than 0 are deleted, and several new triangular surfaces are reconstructed using the coordinate point to be determined as the vertex and the boundary edges of the deleted visible surfaces as the bases. If it is located inside, the point is discarded. After processing each point, the convex polyhedron enclosing the boom space is obtained.

[0099] If the coordinate point to be determined is located inside the area enclosed by the existing vertex set, then the coordinate point to be determined is discarded, and the existing vertex set and surface set remain unchanged.

[0100] After traversing all the coordinate points to be determined in the set of coordinate points to be determined according to the above rules, the boom spatial envelope convex polyhedron is obtained. The data structure of the boom spatial envelope convex polyhedron is a combination of a vertex set and a surface set. The vertex set is a list of coordinate points that constitute the vertices of the convex polyhedron, and the surface set is a number of triangular surfaces. Each triangular surface records the indices of three vertices and the coefficients of the normalized plane equation.

[0101] For example, the coordinates of the point to be determined in S311 Since it is located outside the region enclosed by the existing vertex set, it is added to the vertex set and the relevant triangle surface is reconstructed; the coordinates of the point to be determined... If the vertex is ultimately determined to be inside, it is discarded, and the vertex set remains unchanged.

[0102] S32: Calculate the vertical distance between each surface of the boom spatial envelope convex polyhedron and the preset position coordinates of the charged body, and select the vertical distance with the smallest value from the vertical distances corresponding to each surface as the real-time spatial distance value.

[0103] The boom spatial envelope convex polyhedron output in step S312 represents the spatial occupancy range of continuous boom movement in the form of a set of vertices and a set of surfaces. Subsequent step S4 uses the closest distance from the boom's spatial occupancy range to the charged body as the basis for safety judgment. This step calculates the perpendicular distance from each surface of the boom spatial envelope convex polyhedron to the preset charged body position coordinates and takes the minimum value, quantifying the closest approximation between the spatial occupancy range and the charged body as a real-time spatial distance value.

[0104] Specifically, the preset coordinates of the energized body positions are determined by the base station. The method for determining these coordinates is as follows: During system setup, a BeiDou network RTK positioning terminal is used to perform on-site measurements of the energized parts of the energized body. The measurement results are then converted to the station-center horizontal rectangular coordinates using the same coordinate transformation as S21. For energized parts that cannot be directly measured, the height and planar position of the energized body in the substation's energized body design drawings are converted to the station-center horizontal rectangular coordinates. The preset energized body position coordinates are marked as follows: For example, the preset coordinates of the charged body's position are... The unit is meters, corresponding to a charged body height of 15,000 meters.

[0105] For each triangular surface in the set of convex polyhedral surfaces enclosing the boom space, take the equation of the normalized plane of that surface. ,in Surface index, normal vector Normalized. Preset charged body position coordinates. To the The perpendicular distance to the surface is equal to the absolute value of the value obtained by substituting the coordinates of the pre-defined charged body position into the left-hand side of the equation for the normalized plane of the surface, i.e. .

[0106] To reduce the computational power consumption of real-time calculation in embedded systems and avoid complex 3D point-to-polygon internal projection determination, this step uses the perpendicular distance from the point to the infinite plane containing the surface for approximate calculation. The minimum perpendicular distance is selected from the perpendicular distances corresponding to each surface of the boom space envelope convex polyhedron as the real-time spatial distance value. Since the perpendicular distance from a point to a plane is mathematically always less than or equal to the actual spatial distance from the point to a polygonal facet on that plane, the minimum perpendicular distance of each surface is taken as the real-time spatial distance value. This makes the real-time spatial distance value a conservative lower bound estimate of the distance from the preset charged body position coordinates to the boom space occupied area; that is, the real-time spatial distance value is not greater than the actual closest distance from the preset charged body position coordinates to the boom space occupied area, numerically biased towards a safer side. See also... Figure 8 This is a schematic diagram illustrating the calculation of real-time spatial distance values ​​provided in an embodiment of this application. For example... Figure 8As shown, the preset charged body position coordinates are represented by a star-shaped marker. The boom space envelope convex polyhedron is composed of multiple triangular surfaces. Two dashed lines in the figure indicate the vertical distances from the preset charged body position coordinates to the left and right triangular surfaces, respectively, with the smallest vertical distance highlighted by a thick solid line in the middle. This figure demonstrates that the vertical distance from the preset charged body position coordinates to each triangular surface in the boom space envelope convex polyhedron surface set is calculated, and the smallest vertical distance is selected from the corresponding vertical distances of each surface as the real-time spatial distance value. This real-time spatial distance value serves as a conservative lower bound estimate of the range of the boom space occupied by the preset charged body position coordinates.

[0107] For example, the boom spatial envelope convex polyhedron has a horizontal top surface on the side near the end effector, and the plane containing the top surface is... The unit outward normal vector is Preset charged body position coordinates Substituting the values, we get the vertical distance as The vertical distances from the remaining sides and bottom of the convex polyhedron to the preset charged body position coordinates are all greater than 2.000 meters. Therefore, the minimum value selected from the vertical distances of each surface is 2.000 meters, and the real-time spatial distance value is 2.000 meters. In contrast, if the method of calculating the height difference using only the vehicle body reference coordinates is used, the height difference would be the charged body height of 15.000 meters minus the height of the Beidou network RTK positioning terminal on the roof of the vehicle of 3.000 meters, which is 12.000 meters. This cannot reflect the actual situation where the end effector has approached 2.000 meters.

[0108] The real-time spatial distance value uses the surface of the boom spatial envelope convex polyhedron, rather than a single instantaneous coordinate point, as the distance calculation object, so that the distance calculation covers the space occupied by the end effector's motion trajectory throughout the entire acquisition period. During rapid boom luffing operations, the end effector sweeps across a space along an arc between two adjacent calculation moments. If the distance is calculated using the spatial coordinates of the end effector at a single calculation moment, the intermediate position on this arc segment that is closer to the preset charged body position coordinates will fall between two samples and will not be calculated, resulting in a missed detection within the sampling interval. After condensing the boundary coordinate points on the continuous motion trajectory (including the intermediate coordinate points inserted by the chord height deviation densification mentioned in S311) into a boom spatial envelope convex polyhedron, the surface of the boom spatial envelope convex polyhedron already encompasses the space occupied by the arc segment. The minimum vertical distance from the preset charged body position coordinates to the surface of the boom spatial envelope convex polyhedron will necessarily not be greater than the distance from the preset charged body position coordinates to any discrete sampling point, making the real-time spatial distance value the lower bound of the closest approximation distance for the entire motion trajectory. This avoids the missed detection of instantaneous intrusions within the sampling interval from the perspective of the spatial completeness of the calculation object.

[0109] S4: Determine the dynamic safety distance threshold based on the rate of change of the telescopic joint length value and the amplitude angle value in the robotic arm posture parameter group, compare the real-time spatial distance value with the dynamic safety distance threshold, and output the alarm control command and the alarm status on the display screen.

[0110] The real-time spatial distance value output in step S32 reflects the closest distance from the boom's spatial occupancy area to the preset coordinates of the energized body at the current calculation moment. However, there is a system response delay and a personnel reaction delay between the real-time spatial distance value touching the safety boundary and the alarm sounding and the operator making a braking response. Under high-speed boom operation, the end effector will continue to approach the energized body within the response delay. If a fixed safety distance threshold is used for comparison, the alarm timing will lag behind the actual approaching process of the end effector. This step dynamically corrects the safety distance threshold based on the rate of change of the telescopic joint length and the luffing angle, so that the safety distance threshold is adaptively adjusted with the boom's movement speed. The dynamic safety distance threshold refers to the safety distance judgment boundary obtained by superimposing an advance compensation amount related to the boom's movement speed on the preset basic safety distance.

[0111] Further, step S4 includes:

[0112] S41: Perform differential operations on the expansion joint length value and amplitude angle value at two consecutive acquisition times, and divide by the acquisition time interval to obtain the expansion speed value and amplitude angular velocity value.

[0113] The subsequent step S42 requires the boom movement rate as the basis for correcting the dynamic safety distance threshold. However, the robotic arm posture parameter group directly records position and angle quantities such as the telescopic joint length value and the amplitude angle value, but does not yet include rate information. Therefore, this step performs a differential operation on the telescopic joint length value and amplitude angle value at two consecutive acquisition times to convert the position and angle quantities into rate quantities.

[0114] Specifically, two consecutive acquisition times are taken from the time series of the robotic arm's posture parameters. and Collection time interval It is obtained by subtracting the UTC timestamps of the two acquisition times.

[0115] The telescopic speed value is equal to the difference between the telescopic joint length values ​​at two acquisition times divided by the acquisition time interval, i.e. The unit is meters per second.

[0116] The amplitude angular velocity value is equal to the difference between the amplitude angle values ​​at two acquisition times divided by the acquisition time interval, i.e. The unit is degrees per second.

[0117] For example, the data collection time interval Second, The instantaneous amplitude angle is 59.50 degrees. The amplitude angle at any given moment is 60.00 degrees, and the length of the expansion joint is 7.125 meters at both acquisition times. Therefore, the amplitude angular velocity value... Degrees per second, scaling speed value meters per second.

[0118] S42: Set the motion rate threshold and preset basic safety distance; convert the variable amplitude angular velocity value into the end-effector variable amplitude linear velocity and perform orthogonal vector synthesis with the extension speed value to obtain the end-effector maximum linear velocity. When the end-effector maximum linear velocity is greater than the motion rate threshold, calculate the advance compensation amount according to the product relationship between the end-effector maximum linear velocity and the preset basic safety distance. Add the preset basic safety distance and the advance compensation amount to obtain the dynamic safety distance threshold. When the end-effector maximum linear velocity is less than or equal to the motion rate threshold, directly use the preset basic safety distance as the dynamic safety distance threshold.

[0119] The telescopic speed is measured in meters per second, while the luffing angular velocity is measured in degrees per second. Because these two dimensions are inconsistent, they cannot be directly compared to determine the larger value, nor can they be directly multiplied by the preset basic safety distance measured in meters. Furthermore, the linear velocity at the boom end due to the luffing motion depends on the product of the luffing angular velocity and the boom length. This step requires first converting the luffing angular velocity into the end-effector linear velocity, unifying it with the telescopic speed in meters per second before combining and calculating the advance compensation.

[0120] Specifically, a preset basic safety distance is required. The safety distance is determined based on the voltage level of the energized conductor, and the value is determined according to the minimum safety distance corresponding to different voltage levels in the electrical safety work regulations. For example, a 220 kV voltage level corresponds to a preset basic safety distance. rice.

[0121] Converting the amplitude angular velocity value to the terminal amplitude linear velocity ,in Convert degrees per second to radians per second. The current total length of the boom is equal to the sum of the fixed lengths of each boom section plus the length of the telescopic joint, and is obtained jointly from the boom structural parameters and the robot arm attitude parameters. For example, rice.

[0122] Considering that the telescopic motion is along the boom axis and the luffing motion is perpendicular to the boom axis, and that the two are orthogonal to each other in space, the telescopic velocity value and the end-effector luffing linear velocity are orthogonally vector-synthesized, and the combined modulus length is taken as the maximum end-effector linear velocity. The unit is meters per second.

[0123] Motion speed threshold To distinguish between low-speed fine-tuning operations and high-speed maneuvers, the method for determining the motion rate threshold is as follows: the upper quartile of the maximum linear velocity sample at the end of the boom during the fine-tuning and alignment operation period is used as the motion rate threshold. For example, the motion rate threshold... meters per second.

[0124] When the maximum linear velocity at the end of the trajectory exceeds the motion speed threshold, the advance compensation amount is calculated using the following formula:

[0125]

[0126] Among them, the preset compensation ratio coefficient The method for determining is as follows , The preset response time is equal to the sum of the system response delay of the alarm sounding and the worker's braking reaction time, determined by adding the measured value of the alarm sounding delay to the statistical value of the worker's average braking reaction time. For example, Seconds, substitute into .

[0127] The design principle of the above advance compensation expression is as follows: The term is a multiple of the maximum linear velocity relative motion rate threshold at the end of the boom, dimensionless, reflecting the intensity of the boom's movement. It is expressed as a ratio so that the advance compensation increases linearly with the maximum linear velocity at the end of the boom; multiplied by the preset basic safety distance. The advance compensation amount is correlated with the scene hazard level; the higher the voltage level, the larger the preset basic safety distance and the greater the advance compensation amount obtained at the same movement speed; a preset compensation ratio coefficient is also included. The advance compensation amount is calibrated to the displacement of the end along the approximation direction within the response delay. Substituting into the expression, we get In other words, the advance compensation is numerically equal to the product of the maximum end-effector linear velocity and the preset response time, and physically corresponds to the displacement of the boom as it continues to approach the live conductor before the alarm response is completed. The motion rate threshold acts as a threshold trigger in the expression: when the maximum end-effector linear velocity is lower than or equal to the motion rate threshold, the advance compensation is zero, and the dynamic safety distance threshold equals the preset basic safety distance, without additional compression of the workable space; when the maximum end-effector linear velocity exceeds the motion rate threshold, the advance compensation increases linearly with the increase of the maximum end-effector linear velocity. Together, these two constitute a threshold-triggered piecewise linear compensation mechanism with the motion rate threshold as the segment point, rather than a continuous linear change across the entire velocity range. The overall design goal of the expression is: the larger the maximum end-effector linear velocity, the larger the dynamic safety distance threshold and the earlier the alarm is triggered; when the maximum end-effector linear velocity does not exceed the motion rate threshold, the advance compensation is not added.

[0128] The dynamic safety distance threshold is obtained by adding the preset basic safety distance to the advance compensation amount. When the maximum linear velocity at the end point is less than or equal to the motion rate threshold, the preset basic safety distance is directly used as the dynamic safety distance threshold, i.e. See also Figure 9 This is a schematic diagram of the dynamic safety distance threshold provided in the embodiments of this application. Figure 9 As shown, the left side uses a right-angled triangle to represent the orthogonal vector composition relationship where the extension / retraction speed is the base, the terminal amplitude-variable linear velocity is the vertical side, and the terminal maximum linear velocity is the hypotenuse. The right side uses two adjacent rectangles to represent the preset basic safety distance and the advance compensation amount, with the sum of the two indicated by curly braces below as the dynamic safety distance threshold. This diagram illustrates the calculation process of converting the amplitude-variable angular velocity value into the terminal amplitude-variable linear velocity, performing orthogonal vector composition with the extension / retraction speed value to obtain the terminal maximum linear velocity, calculating the advance compensation amount based on the terminal maximum linear velocity, and finally adding the preset basic safety distance and the advance compensation amount to obtain the dynamic safety distance threshold.

[0129] For example, the scaling speed value Variable amplitude angular velocity value Degrees per second, current total length of boom meters, then the terminal amplitude linear velocity meters per second, maximum linear velocity at the end The maximum linear velocity at the end of the trajectory is 1.058 meters per second, which is greater than the velocity threshold of 0.300 meters per second. Therefore, the advance compensation amount is calculated. meters, dynamic safe distance threshold rice.

[0130] S43: Compare the real-time spatial distance value with the dynamic safety distance threshold. When the real-time spatial distance value is less than the dynamic safety distance threshold, generate an alarm trigger command, control the alarm to sound an alarm, and switch the current distance value on the host display to the red alarm state. When the real-time spatial distance value is greater than or equal to the dynamic safety distance threshold, generate a normal operation mark and maintain the current display state of the host display.

[0131] The real-time spatial distance value output in step S32 and the dynamic safety distance threshold output in step S42 are both measured in meters and are within the same station-centric Cartesian coordinate system, providing a basis for direct comparison. This step compares the real-time spatial distance value with the dynamic safety distance threshold and transforms the comparison result into specific control actions for the alarm and the host display screen, forming a closed loop from distance quantification to on-site audible and visual alarms.

[0132] Specifically, the real-time spatial distance value output in step S32 is compared with the dynamic safety distance threshold output in step S42.

[0133] When the real-time spatial distance value is less than the dynamic safe distance threshold, an alarm trigger command is generated. The alarm trigger command is sent to the alarm device via the serial communication module at RS232 level, which controls the alarm device to emit an alarm sound. At the same time, the host display screen switches the current distance value to the red alarm state.

[0134] When the real-time spatial distance value is greater than or equal to the dynamic safety distance threshold, a normal operation mark is generated, the alarm does not sound, and the host display screen maintains the current display status and normal display color.

[0135] For example, if the real-time spatial distance is 2.000 meters and the dynamic safety distance threshold is 4.587 meters, an alarm trigger command is generated because 2.000 meters is less than 4.587 meters. The alarm sounds, and the current distance value on the host display switches to a red alarm state. In contrast, if a fixed preset safety distance of 3.000 meters is used as the threshold, the alarm will only trigger when the real-time spatial distance drops to 3.000 meters. However, with the dynamic safety distance threshold of 4.587 meters, the alarm will trigger as soon as the real-time spatial distance drops to 4.587 meters, which is 1.587 meters earlier than the fixed threshold. Furthermore, if the method of calculating the height difference of 12.000 meters based solely on the vehicle's reference coordinates is used, no alarm will be triggered because 12.000 meters is greater than 3.000 meters, resulting in the failure in the example scenario where the boom crosses the boundary but the system does not alarm.

[0136] The dynamic safety distance threshold used in this step is obtained by adding a preset basic safety distance to an advance compensation amount. The advance compensation amount increases linearly with the maximum linear velocity at the end of the boom when it exceeds the motion rate threshold, and becomes zero when it does not exceed the motion rate threshold. The two form a threshold-triggered piecewise linear relationship with the motion rate threshold as the dividing point. The original design goal of the dynamic safety distance threshold was to solve the problem of delayed alarm intrusion caused by system response delay and personnel reaction delay during high-speed boom operation, that is, to trigger the alarm earlier by expanding the safety distance judgment boundary when the boom rapidly approaches a live conductor. However, the mathematical structure of the advance compensation amount being proportional to the maximum linear velocity at the end of the boom and having the motion rate threshold as the trigger lower bound naturally causes the advance compensation amount to become zero under low-speed fine-tuning operation conditions of the boom. The dynamic safety distance threshold degenerates into the preset basic safety distance without occupying additional working space. In substation maintenance, low-speed boom fine-tuning and alignment operations are common, and the available working space and the timeliness of safety warnings are inherently contradictory: a larger safety distance threshold results in more timely warnings but compresses the available working space, while a smaller threshold provides more working space but leads to delayed warnings at high speeds. The motion rate threshold triggering structure ensures that the dynamic safety distance threshold matches the fixed preset safety distance at low speeds without compressing the working space, and automatically expands with the maximum linear velocity at the end point at high speeds to guarantee timely warnings. This ability to simultaneously meet the needs of both types of operations without adding extra sensors or judgment modules is not the original design goal of advance compensation, but rather a mathematically inherent characteristic of the motion rate threshold triggering structure and the linear compensation structure. It overcomes the inherent limitation that a fixed safety distance threshold cannot simultaneously compress the working space at low speeds and delay warnings at high speeds.

[0137] In summary, this embodiment is based on the chain coupling of the vehicle body reference coordinates with the boom rotation angle, luffing angle, and telescopic joint length. Through multi-source data synchronization in step S1, step S2 recursively extrapolating the joint coordinate chain, step S3 constructing the boom spatial envelope convex polyhedron and calculating the minimum vertical distance, and step S4 correcting the motion rate coupling threshold and outputting audible and visual alarms, the physical coordinates of a single Beidou network RTK positioning terminal fixedly installed on the vehicle body are converted layer by layer into the real spatial coordinate sequence of the end effector. This is then condensed into the boom spatial occupancy area and outputs the real-time spatial distance value. Finally, the alarm and host display are driven by a dynamic safety distance threshold that adapts to the maximum linear velocity of the end effector. This forms a complete closed loop from coordinate calculation and envelope construction to threshold adaptation and on-site alarms, eliminating the spatial representation deviation between the single-point positioning of the vehicle body and the multi-degree-of-freedom dynamic mechanical structure of the boom at the physical level.

[0138] Example 2:

[0139] This embodiment, based on Embodiment 1, provides a centimeter-level system for determining the safe distance of live conductors on special operation vehicles, such as... Figure 10 As shown, it includes:

[0140] The robotic arm posture parameter group generation module is used to collect the vehicle body reference coordinates through the Beidou network RTK positioning terminal strongly magnetically attached to the vehicle body, and simultaneously collect the rotation angle value, amplitude angle value and telescopic joint length value through sensors installed on the boom rotation mechanism, luffing mechanism and telescopic mechanism to generate the robotic arm posture parameter group;

[0141] The end effector spatial coordinate sequence generation module is used to construct a joint coordinate chain list according to the hinge sequence of each section of the arm based on the robotic arm posture parameter group, and recursively calculate the end effector spatial coordinates section by section along the chain list to obtain the end effector spatial coordinates, and arrange the end effector spatial coordinates at continuously collected times to generate an end effector spatial coordinate sequence.

[0142] The real-time spatial distance value calculation module is used to construct a boom spatial envelope convex polyhedron based on the spatial coordinate sequence of the end effector, calculate the distance between the surface of the boom spatial envelope convex polyhedron and the preset position coordinates of the charged body, and obtain the real-time spatial distance value.

[0143] The dynamic safety distance threshold determination and alarm module is used to determine the dynamic safety distance threshold based on the rate of change of the telescopic joint length value and the amplitude angle value in the robotic arm posture parameter group, compare the real-time spatial distance value with the dynamic safety distance threshold, and output alarm control commands and alarm status on the display screen.

Claims

1. A centimeter-level positioning measurement method for the safe distance of live conductors on special operation vehicles, characterized in that, include: The vehicle's reference coordinates are collected by a Beidou network RTK positioning terminal that is strongly magnetically attached to the vehicle body. Simultaneously, the rotation angle, amplitude angle, and telescopic joint length values ​​are collected by sensors installed on the boom rotation mechanism, luffing mechanism, and telescopic mechanism to generate a set of robotic arm posture parameters. Based on the robotic arm posture parameter set, a joint coordinate chain is constructed according to the hinge sequence of each section of the arm, and the solution is recursively calculated section by section along the chain to obtain the spatial coordinates of the end effector. The spatial coordinates of the end effector at continuously collected times are arranged to generate a spatial coordinate sequence of the end effector. A boom spatial envelope convex polyhedron is constructed based on the spatial coordinate sequence of the end effector. The distance between the surface of the boom spatial envelope convex polyhedron and the position coordinates of the preset charged body is calculated to obtain the real-time spatial distance value. The dynamic safety distance threshold is determined based on the rate of change of the telescopic joint length value and the amplitude angle value in the robotic arm posture parameter group. The real-time spatial distance value is compared with the dynamic safety distance threshold, and an alarm control command and an alarm status display are output.

2. The centimeter-level positioning measurement method for the safe distance of a live conductor on a special operation vehicle according to claim 1, characterized in that, The vehicle body reference coordinates collected include: The BeiDou network RTK positioning terminal receives satellite carrier phase observations and differential corrections issued by the base station. Mode switching is accomplished by fusing sensor signals; The vehicle body reference coordinates are obtained by calculation, and the vehicle body reference coordinates include longitude, latitude and geodetic elevation values.

3. The centimeter-level positioning measurement method for the safe distance of a live conductor on a special operation vehicle according to claim 1, characterized in that, The synchronous acquisition of slewing angle, luffing angle, and telescopic joint length values ​​by sensors installed on the boom slewing mechanism, luffing mechanism, and telescopic mechanism includes: The slewing angle value is acquired by an angle encoder installed on the boom slewing mechanism; The amplitude angle value is acquired by an angle sensor installed on the amplitude mechanism; The length value of the expansion joint is collected by a displacement sensor installed on the expansion mechanism.

4. The centimeter-level positioning measurement method for the safe distance of a live conductor on a special operation vehicle according to claim 1, characterized in that, The generated robotic arm posture parameter set includes: Align the vehicle body reference coordinates, the rotation angle value, the amplitude angle value, and the telescopic joint length value according to their respective acquisition timestamps to generate the robotic arm posture parameter group; The data structure of the robotic arm posture parameter group is a time sequence arranged according to the calculation time. Each element in the sequence is a quintuple, which includes the calculation time, the vehicle body reference coordinates, the rotation angle value, the amplitude angle value, and the telescopic joint length value.

5. The centimeter-level positioning measurement method for the safe distance of a live conductor on a special operation vehicle according to claim 1, characterized in that, The construction of the joint coordinate linked list includes: The vehicle body reference coordinates are used as the coordinates of the first node in the joint coordinate chain; Based on the fixed length values ​​of each boom section in the boom structure parameters and in combination with the slewing angle value, the projection direction of the bottom boom section in the horizontal plane is determined.

6. A centimeter-level positioning measurement method for the safe distance of a live conductor on a special operation vehicle according to claim 5, characterized in that, The phrase "using the vehicle body reference coordinates as the coordinates of the first node of the joint coordinate linked list" includes: The longitude, latitude, and geodetic elevation values ​​of the vehicle body reference coordinates are converted into geocentric rectangular coordinates using a standard conversion formula. Using the preset center point of the base station as the origin, the coordinates of the first node of the joint coordinate chain are output after being converted into the horizontal rectangular coordinates of the center point through translation and rotation.

7. The centimeter-level positioning measurement method for the safe distance of a live conductor on a special operation vehicle according to claim 1, characterized in that, The recursive calculation along the linked list section by section yields the spatial coordinates of the end effector, including: The process proceeds sequentially along the joint coordinate chain, starting from the coordinates of the previous node for each pair of adjacent nodes in the joint coordinate chain. The direction angle of the spatial displacement component is determined by the amplitude angle value, and the modulus of the spatial displacement component is determined by the expansion joint length value. The spatial displacement components are converted into three-dimensional coordinate increments and then superimposed onto the coordinates of the previous node to obtain the coordinates of the current node. The recursive process is repeated until the end node of the joint coordinate chain is reached to obtain the spatial coordinates of the end effector.

8. A centimeter-level positioning measurement method for the safe distance of a live conductor on a special operation vehicle according to claim 1, characterized in that, The constructed boom spatial envelope convex polyhedron includes: Extract the boundary coordinates of each articulation point of the boom section during continuous operation from the spatial coordinate sequence of the end effector, and remove redundant coordinates inside. By sequentially comparing the relative positional relationship between the spatial coordinates of the end effector and each boundary coordinate point at adjacent acquisition times, it is determined whether the current coordinate point is located outside the area enclosed by the existing set of vertices. If the current coordinate point is located outside the area enclosed by the existing vertex set, then the current coordinate point is added to the vertex set of the boom space envelope convex polyhedron. If it is located on the inside, discard the current coordinate point, and after processing each point, obtain the boom space envelope convex polyhedron.

9. A centimeter-level positioning measurement method for the safe distance of a live conductor on a special operation vehicle according to claim 1, characterized in that, The calculation of the distance between the surface of the boom spatial envelope convex polyhedron and the preset position coordinates of the charged body, to obtain the real-time spatial distance value, includes: Calculate the vertical distance between each surface of the boom spatial envelope convex polyhedron and the preset position coordinates of the charged body; The vertical distance with the smallest value is selected from the vertical distances corresponding to each surface as the real-time spatial distance value.

10. A centimeter-level positioning measurement method for the safe distance of a live conductor on a special operation vehicle according to claim 1, characterized in that, Determining the dynamic safety distance threshold based on the rate of change of the telescopic joint length value and the amplitude angle value in the robotic arm posture parameter group includes: The telescopic joint length value and the amplitude angle value at two consecutive acquisition times are differentially calculated and divided by the acquisition time interval to obtain the telescopic speed value and the amplitude angular velocity value. Set the movement rate threshold and preset basic safety distance; After converting the variable amplitude angular velocity value into the terminal variable amplitude linear velocity, it is orthogonally vector-synthesized with the extension and contraction velocity value to obtain the terminal maximum linear velocity. When the maximum linear velocity at the end is greater than the motion rate threshold, the advance compensation amount is calculated according to the product relationship between the maximum linear velocity at the end and the preset basic safety distance, and the preset basic safety distance and the advance compensation amount are added to obtain the dynamic safety distance threshold. When the maximum linear velocity at the end point is less than or equal to the motion rate threshold, the preset basic safety distance is directly used as the dynamic safety distance threshold.

11. A centimeter-level positioning measurement method for the safe distance of a live conductor on a special operation vehicle according to claim 1, characterized in that, The step of comparing the real-time spatial distance value with the dynamic safety distance threshold and outputting alarm control commands and display alarm status includes: The real-time spatial distance value is compared numerically with the dynamic safety distance threshold; When the real-time spatial distance value is less than the dynamic safety distance threshold, an alarm trigger command is generated to control the alarm to sound an alarm and switch the current distance value on the host display to a red alarm state. When the real-time spatial distance value is greater than or equal to the dynamic safety distance threshold, a normal operation mark is generated, and the current display state of the host screen is maintained.

12. A centimeter-level positioning and measurement system for the safe distance of a live conductor on a special operation vehicle, used to implement the centimeter-level positioning and measurement method for the safe distance of a live conductor on a special operation vehicle as described in any one of claims 1 to 11, characterized in that, The system includes: The robotic arm posture parameter group generation module is used to collect the vehicle body reference coordinates through the Beidou network RTK positioning terminal strongly magnetically attached to the vehicle body, and simultaneously collect the rotation angle value, amplitude angle value and telescopic joint length value through sensors installed on the boom rotation mechanism, luffing mechanism and telescopic mechanism to generate the robotic arm posture parameter group; The end effector spatial coordinate sequence generation module is used to construct a joint coordinate chain list according to the hinge sequence of each section of the arm based on the robotic arm posture parameter group, and recursively calculate the end effector spatial coordinates section by section along the chain list to obtain the end effector spatial coordinates, and arrange the end effector spatial coordinates at continuously collected times to generate an end effector spatial coordinate sequence. The real-time spatial distance value calculation module is used to construct a boom spatial envelope convex polyhedron based on the spatial coordinate sequence of the end effector, calculate the distance between the surface of the boom spatial envelope convex polyhedron and the preset position coordinates of the charged body, and obtain the real-time spatial distance value. The dynamic safety distance threshold determination and alarm module is used to determine the dynamic safety distance threshold based on the rate of change of the telescopic joint length value and the amplitude angle value in the robotic arm posture parameter group, compare the real-time spatial distance value with the dynamic safety distance threshold, and output alarm control commands and alarm status on the display screen.

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