Cylindrical structural member full-circumference detection method and system based on sensor group, and storage medium

Abstract

The invention relates to a sensor group-based full-circumference detection method and system for a cylindrical structural member and a storage medium, and the method comprises the following steps: responding to a trigger signal that the cylindrical structural member reaches a preset measurement point, so as to generate a synchronous collection instruction, and sending the synchronous collection instruction to a sensor group; wherein the sensor group comprises at least three 3D line laser sensors which are annularly arranged in the circumferential direction of the cylindrical structural component; controlling the sensor group to execute the synchronous acquisition instruction, and controlling the sensor group and the cylindrical structural member to move relatively so as to acquire a plurality of groups of three-dimensional point cloud data sets in the movement process; generating a full-circumference three-dimensional point cloud model representing the circumferential surface of the cylindrical structural member according to the plurality of groups of three-dimensional point cloud data sets; and on the basis of the full-circumference three-dimensional point cloud model, calculating full-circumference parameters of the cylindrical structural member so as to judge whether the cylindrical structural member is qualified or not according to the full-circumference parameters.

Description

Technical Field

[0001] This invention relates to the fields of machine vision and cylindrical structural component inspection technology, specifically to a method, system, and storage medium for full circumference inspection of cylindrical structural components based on a sensor array. Background Technology

[0002] With the rapid development of new energy vehicles and energy storage industries, the demand and quality requirements for cylindrical structural components (such as various lithium-ion structural components) are increasing. The consistency of their shell diameter, cylindricity, and other key process parameters directly determine the energy density, safety performance, and assembly accuracy of the structural components in modules. Therefore, achieving high-speed, high-precision, and comprehensive online full inspection has become a core link in ensuring product quality and production efficiency.

[0003] Currently, existing technologies for measuring the outer diameter and cylindricity of cylindrical structural components mainly rely on the following methods, each with significant limitations: First, contact measurement, while achieving high absolute accuracy, suffers from low efficiency, making it difficult to meet production line cycle time requirements. Furthermore, the measuring force applied by the contact probe may cause minute deformations in the thin-walled shell of the structural component, introducing measurement errors. Additionally, the equipment is expensive and requires a strict operating environment, making it unsuitable for integration into high-speed production lines for full inspection. Second, non-contact methods such as single-point laser scanning or two-dimensional visual measurement typically only acquire partial circumferential contours or two-dimensional projection information at a specific axial position of the structural component, failing to simultaneously acquire complete circumferential three-dimensional topographic data. This limits its application to sampling inspection, easily missing minute defects such as localized depressions and protrusions on the surface of the structural component. Moreover, based on finite cross-sections or two-dimensional images, it is difficult to accurately calculate the true cylindricity parameters reflecting the overall shape, resulting in incomplete measurement dimensions and insufficient reliability. Third, while scanning with a single 3D line laser sensor can acquire three-dimensional point clouds, covering the entire circumference of the cylinder typically requires an additional precision rotating mechanism to drive the structural components or the sensor itself for rotational scanning. This not only increases system complexity and cost but also prolongs the measurement cycle due to the introduction of mechanical motion. Furthermore, dynamic errors during rotation (such as radial runout and axial movement) directly affect the stability and accuracy of data acquisition, making it difficult to guarantee the reliability of the measurement results. This also limits its application in high-speed online inspection.

[0004] In addition, although there are existing studies on 3D line laser measurement for rigid parts such as shafts, they are mostly applied to controlled offline inspection environments. The system calibration process is complex (for example, it is necessary to accurately model and compensate for sensor installation eccentricity and workpiece clamping eccentricity), making it difficult to adapt to online measurement scenarios in the battery and structural component industries where models are switched rapidly and the requirements for inspection cycle and stability are extremely high.

[0005] This application relates to the development of a method, system, and storage medium for detecting the full circumference of cylindrical structural components based on a sensor array, in order to solve the aforementioned problems. Summary of the Invention

[0006] In order to achieve the above-mentioned objectives and other advantages of the present invention, a first objective of the present invention is to provide a method for detecting the full circumference of a cylindrical structural component based on a sensor array, comprising the following steps: In response to the trigger signal that the cylindrical structural component reaches the preset measurement point, a synchronous acquisition command is generated and sent to the sensor group; In response to a trigger signal that the cylindrical structural member reaches a preset measurement point, a synchronous acquisition command is generated and sent to the sensor group; wherein, the sensor group includes at least three 3D line laser sensors arranged in a ring around the circumference of the cylindrical structural member; The sensor group is controlled to execute the synchronous acquisition command, and the relative movement between the sensor group and the cylindrical structure is controlled to acquire several sets of three-dimensional point cloud data during the movement. A full-circumference three-dimensional point cloud model representing the circumferential surface of the cylindrical structural component is generated based on the aforementioned sets of three-dimensional point cloud data. Based on the full circumference three-dimensional point cloud model, the full circumference parameters of the cylindrical structural component are calculated, and the qualification of the cylindrical structural component is determined according to the full circumference parameters.

[0007] Furthermore, the total circumference parameter includes the diameter and cylindricity of the cylindrical structural member.

[0008] Furthermore, calculating the diameter of the cylindrical structural member includes the following steps: Point cloud data of multiple cross sections are extracted from the full circumference three-dimensional point cloud model at multiple preset height positions from the bottom of the cylindrical structural member, along the axial direction of the cylindrical structural member. For each of the point cloud data sections, a circular fit is performed to calculate the diameter of the fitted circle corresponding to each cross section. Statistical analysis was performed on all the fitted circle diameters to obtain diameter measurement data including their mean, maximum, minimum and standard deviation; The average value of the fitted circle diameter is used as the diameter measurement result of the cylindrical structure.

[0009] Furthermore, the circular fitting employs the least squares method.

[0010] Furthermore, the plurality of preset height positions include 5mm, 10mm, 15mm, 25mm, 47mm, 70mm, 85mm and 90mm from the bottom of the cylindrical structural member.

[0011] Further, calculating the cylindricity of the cylindrical structural member includes the following steps: A cylindrical surface is fitted to the full-circumference three-dimensional point cloud model to obtain a reference cylindrical surface; Calculate the normal distance from all measurement points in the full-circumference three-dimensional point cloud model to the reference cylindrical surface; Determine the maximum and minimum values ​​among all the stated normal distances; The difference between the maximum value and the minimum value is calculated to obtain the extreme difference in cylindricity of the cylindrical structural component.

[0012] Furthermore, the cylindrical surface fitting employs the least squares method or the minimum region method.

[0013] Furthermore, the line laser planes of the 3D line laser sensor are all perpendicular to the axis of the cylindrical structure.

[0014] Furthermore, prior to the step of generating the synchronous acquisition command, a system calibration step is also included: Fix the polyhedral calibration block at the preset measurement station; The sensor group is controlled to scan the polyhedral calibration block to obtain a calibration point cloud dataset in each sensor coordinate system; Based on the mapping relationship between the polyhedral calibration block and the calibration point cloud dataset, obtain the coordinate transformation matrix from each sensor coordinate system to the global coordinate system; Based on the coordinate transformation matrix, preset system calibration parameters are established.

[0015] Furthermore, the polyhedral calibration block is a high-precision pyramid block with known precise dimensions.

[0016] Furthermore, after generating the full-body 3D point cloud model, a point cloud filtering step is also included: Optical filtering and point cloud post-processing algorithms are used to identify and remove outlier noise points caused by reflection in the full-body 3D point cloud model.

[0017] Furthermore, the step of generating a synchronous acquisition command in response to a trigger signal indicating that the cylindrical structural member has reached a preset measurement point includes the following steps: The position of the cylindrical structural component is monitored in real time by a photoelectric sensor located at the preset measurement point. When the photoelectric sensor determines that the preset reference position of the cylindrical structural component has entered its effective detection area, it generates the trigger signal and transmits it to the main control unit. In response to the trigger signal, the synchronous acquisition command is generated based on the preset measurement timing.

[0018] Furthermore, the synchronous acquisition command is used to control all sensors in the sensor group to be exposed synchronously in order to capture the laser lines on the surface of the cylindrical structure.

[0019] Furthermore, generating a full-circumference three-dimensional point cloud model representing the circumferential surface of the cylindrical structural member includes the following steps: Using the coordinate transformation matrix in the system calibration parameters, the three-dimensional point cloud data sets of each group are transformed to the global coordinate system to complete the initial registration; Based on the geometric features of the overlapping regions of the transformed sets of three-dimensional point cloud data, an iterative nearest point algorithm is used for accurate registration. The several sets of precisely registered 3D point cloud datasets are merged into a single, seamless full-body 3D point cloud model.

[0020] A second objective of this invention is to provide a full circumference detection system for cylindrical structural components based on a sensor array, comprising the following modules: The instruction generation module, in response to a trigger signal that the cylindrical structural component reaches a preset measurement point, generates a synchronous acquisition instruction and sends it to the sensor group; wherein, the sensor group includes at least three 3D line laser sensors arranged in a ring around the circumference of the cylindrical structural component; The data acquisition module is used to control the sensor group to execute the synchronous acquisition command, and at the same time control the relative movement of the sensor group and the cylindrical structure to acquire several sets of three-dimensional point cloud data during the movement. The model generation module is used to generate a full-circumference three-dimensional point cloud model representing the circumferential surface of the cylindrical structural component based on the several sets of three-dimensional point cloud data. The detection module is used to calculate the full circumference parameters of the cylindrical structural component based on the full circumference three-dimensional point cloud model, so as to determine whether the cylindrical structural component is qualified based on the full circumference parameters.

[0021] A third objective of this invention is to provide a readable storage medium having a computer program stored thereon, characterized in that, when the computer program is executed by a processor, it implements a method for detecting the full circumference of a cylindrical structure based on a sensor array.

[0022] Compared with the prior art, the beneficial effects of the present invention are: This invention relates to a method, system, and storage medium for full circumference detection of cylindrical structural components based on a sensor array. By synchronously triggering at least three 3D line laser sensors deployed in a ring, simultaneous, full-coverage 3D data acquisition of the 360° circumferential surface of the structural component's shell is achieved in a single relative motion. Specifically, by unifying multi-view point cloud data to a global coordinate system through preset system calibration parameters, and after registration and fusion processing, a full circumference 3D point cloud model capable of accurately characterizing the complete outer surface morphology of the structural component is generated. This effectively overcomes a series of inherent limitations of traditional contact measurement methods, such as low efficiency and force deformation, as well as the inability of non-contact single-point or single-sensor scanning to acquire complete circumferential information and the introduction of dynamic errors due to mechanical rotation. It can not only calculate the diameter of the structural component and the cylindricity parameters reflecting the overall shape accuracy with high precision and efficiency, but also reliably identify minute defects such as local depressions and protrusions, thereby achieving non-destructive, full inspection of the key geometric dimensions and morphology of cylindrical structural components. This invention significantly improves the cycle time, accuracy, and consistency of online measurement, providing a stable and reliable technical means for closed-loop quality control and process optimization in the production of structural components, and strongly supporting the new energy industry's requirements for high quality and high consistency of structural component products.

[0023] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it according to the contents of the specification, the preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings. Specific embodiments of the present invention are given in detail below with reference to the accompanying drawings. Attached Figure Description

[0024] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings: Figure 1 This is a flowchart of the full circumference detection process for a cylindrical structure based on a sensor array, as described in this application. Figure 2 The flowchart for generating synchronous acquisition instructions is shown in Example 1; Figure 3 The system calibration flowchart is shown in Example 1; Figure 4 The flowchart for generating a full-circumference three-dimensional point cloud model representing the circumferential surface of a cylindrical structural component, as described in Example 1; Figure 5 This is a schematic diagram of the full-circumference three-dimensional point cloud model described in Example 1; Figure 6 This is a flowchart illustrating the calculation of the diameter of the cylindrical structural member as described in Example 1; Figure 7This is a flowchart illustrating the calculation of the cylindricity of the cylindrical structural component as described in Example 1; Figure 8 This is a flowchart illustrating the process of determining whether a cylindrical structural component is qualified based on the total circumference parameter as described in Example 1. Figure 9 This is a schematic diagram of the full circumference detection system for cylindrical structural members based on a sensor array as described in Example 2. Figure 1 ; Figure 10 This is a schematic diagram of the full circumference detection system for cylindrical structural members based on a sensor array as described in Example 2. Figure 2 ; Figure 11 This is a schematic diagram of a computer-readable storage medium in Example 3. Detailed Implementation

[0025] The present invention will now be further described in conjunction with the accompanying drawings and specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0026] In the following description, the use of suffixes such as "module," "part," or "unit" to denote elements is solely for the purpose of illustrative purposes and has no specific meaning in itself. Therefore, "module," "part," or "unit" may be used interchangeably.

[0027] In the mass production of cylindrical structural components, achieving 100% online inspection of key dimensions such as shell diameter and cylindricity is a core aspect of ensuring product consistency and safety. Existing conventional inspection methods, such as contact measurement or single-point scanning, generally suffer from low efficiency or incomplete data. Scanning schemes that rely on the rotation of structural components or sensors, on the other hand, introduce motion mechanisms that restrict cycle time and affect accuracy, making it difficult to meet the requirements of high-speed, high-stability production lines. Furthermore, traditional belt-driven inspection methods are susceptible to vibration and positioning deviations, making it difficult to guarantee measurement repeatability.

[0028] To overcome the aforementioned limitations, this invention proposes an innovative non-contact, full-circumference synchronous measurement scheme. Its core lies in employing a fixed measurement network, or sensor group, composed of multiple 3D line laser sensors arranged in a ring. With a single trigger, it can synchronously capture three-dimensional point cloud data of the entire circumferential surface of a structural component, eliminating the need for any rotational motion and fundamentally avoiding dynamic errors, thus achieving a balance between high efficiency and high precision.

[0029] It should be noted that this invention is designed for high-precision detection environments and can be adapted to, but is not limited to, the following specific implementation scenarios: First, the cylindrical structural component is supported by a dedicated clamping bracket with precise positioning function (e.g., a structure with multi-point support at the bottom) and moves linearly, in which case all sensors in the sensor group are stationary scanning; Second, the structural component remains suspended and stationary at the detection station, and the moving scan is performed by a motion mechanism integrating the sensor group. Both architectures effectively eliminate the vibration and positioning uncertainty caused by traditional conveyor belts, providing an extremely stable and reliable benchmark for the detection system.

[0030] Example 1 This invention provides a method for detecting the full circumference of a cylindrical structural component based on a sensor array, such as... Figure 1 As shown, the specific steps include the following: S101, in response to a trigger signal that the cylindrical structural member reaches a preset measurement point, a synchronous acquisition command is generated and sent to the sensor group; wherein, the sensor group includes at least three 3D line laser sensors arranged in a ring around the circumference of the cylindrical structural member; S102, control the sensor group to execute the synchronous acquisition command, and at the same time control the sensor group to move relative to the cylindrical structure to acquire several sets of three-dimensional point cloud data during the movement. S103, Generate a full-circumference three-dimensional point cloud model representing the circumferential surface of the cylindrical structural component based on the aforementioned sets of three-dimensional point cloud data. S104. Based on the full circumference three-dimensional point cloud model, calculate the full circumference parameters of the cylindrical structural component, and determine whether the cylindrical structural component is qualified based on the full circumference parameters.

[0031] In some embodiments, the step S101, which responds to a trigger signal indicating that the cylindrical structural member has reached a preset measurement point, generates a synchronous acquisition command, such as... Figure 2 As shown, it includes the following steps: S1011, The position of the cylindrical structural component is monitored in real time by a photoelectric sensor located at the preset measurement point; S1012, when the photoelectric sensor determines that the preset reference position of the cylindrical structural component has entered its effective detection area, it generates the trigger signal and transmits it to the main control unit; S1013, the main control unit responds to the trigger signal and generates the synchronous acquisition command based on the preset measurement timing.

[0032] In a preferred embodiment, the preset measurement point refers to a spatial location predefined and calibrated during the detection process, which is set at or before the starting boundary of the optimal scanning field of view of the sensor group. The setting of the preset measurement point is intended to ensure that after the trigger signal is issued, the relative movement between the structural component and the sensor group allows the entire section of the structural component to pass through the scanning area of ​​the sensor group completely and smoothly, thereby ensuring the acquisition of effective point cloud data covering the entire circumference without omissions.

[0033] In a preferred embodiment, the photoelectric sensor described in step S1011 is used to detect the positioning status of the cylindrical structural member in a non-contact manner.

[0034] Specifically, it should be understood that the photoelectric sensor preferably includes a transmitter and a receiver aligned with each other and separately disposed; the transmitter and receiver are installed across both sides of the cylindrical structural member's movement path or suspended position, such that when the preset reference position of the cylindrical structural member (e.g., the end face or a specific edge of the structural member) reaches the precise measurement position, it can instantly block or allow the light beam emitted by the transmitter to the receiver, thereby generating a jump signal as the trigger signal. Alternatively, the photoelectric sensor can also be a reflective photoelectric sensor, with its transmitter and receiver integrated into one unit, generating the trigger signal by detecting changes in light intensity reflected from the surface of the structural member. The photoelectric sensor has extremely high response speed and repeatability accuracy to match high-speed detection cycles and eliminate false triggering that may be caused by vibration or positioning deviation.

[0035] In a preferred embodiment, in step S1013, after receiving the trigger signal from the photoelectric sensor, the main control unit immediately calls the preset measurement timing control logic to generate the synchronous acquisition command.

[0036] Specifically, it should be understood that the logic operates based on a set of preset measurement timing parameters, which include at least: trigger delay time, sensor internal exposure time, and frame interval for continuous acquisition.

[0037] In another preferred embodiment, the synchronous acquisition command can be configured as a single-trigger mode or a continuous-trigger mode. In continuous mode, after issuing the first synchronization pulse, the main control unit will periodically issue subsequent pulses according to a preset frame interval, and perform continuous and equally spaced data acquisition during the relative movement of the structural components until the structural components completely move out of the scanning field of view.

[0038] Specifically, it should be understood that during the data acquisition process, the main control unit can also integrate a compensation mechanism for inherent system delays such as sensor response delay and signal transmission delay, and maintain the consistency of the internal clocks of each sensor through precision clock synchronization technology (such as PTP or a dedicated synchronization controller), thereby ensuring strict synchronization and alignment of all data acquisition points in the time dimension, laying the foundation for the accurate fusion of subsequent point cloud data.

[0039] In a preferred embodiment, the synchronous acquisition command is used to control all 3D line laser sensors in the sensor group to be exposed synchronously in order to capture laser lines on the surface of the cylindrical structure.

[0040] In some embodiments, the line laser plane of the 3D line laser sensor in step S101 is perpendicular to the axis of the cylindrical structure and points towards the axial direction of the cylindrical structure.

[0041] Specifically, it should be understood that upon receiving a synchronous acquisition command, each 3D line laser sensor immediately activates its internal optical scanning and image capture unit, continuously emitting laser lines at a preset fixed frequency to acquire data, thereby discretizing a continuous circumferential contour band on the surface of the structural component into a series of points with three-dimensional coordinates. Since all 3D line laser sensors are strictly triggered synchronously, the data frames they acquire at the same moment constitute a set of three-dimensional point cloud data that are perfectly aligned in time. As the relative motion continues, the sensors will continuously and synchronously output several such sets of data arranged in chronological order. Each set of three-dimensional point cloud datasets completely contains a slice of three-dimensional point cloud covering the entire circumferential surface of the structural component captured by all sensors on the ring at the same sampling moment.

[0042] This application utilizes a ring-shaped layout distributed circumferentially around the structural component. Each 3D line laser sensor projects a laser line perpendicular to the component's axis and irradiates a corresponding arc-shaped outer surface area. This ensures that a single measurement covers the entire circumferential contour of the component without rotating the workpiece or sensor, fundamentally eliminating the dynamic errors, mechanical wear, and speed bottlenecks caused by rotational mechanisms. The measurement cycle time depends only on the speed of the relative linear motion and the scanning frequency of the 3D line laser sensor, achieving a detection efficiency far exceeding that of rotational scanning schemes. Simultaneously, it avoids the adverse effects of vibration and radial runout caused by rotational motion on point cloud accuracy and stability, providing a reliable foundation for high-precision, high-repeatability online full inspection.

[0043] In some embodiments, before step S101, such as Figure 3 As shown, it also includes system calibration steps: S111, Fix the polyhedral calibration block to the preset measurement station; S112, control the sensor group to scan the polyhedral calibration block and obtain the calibration point cloud dataset under each sensor coordinate system; S113, Based on the mapping relationship between the polyhedral calibration block and the calibration point cloud dataset, obtain the coordinate transformation matrix from each sensor coordinate system to the global coordinate system; S114. Based on the coordinate transformation matrix, establish preset system calibration parameters.

[0044] In a preferred embodiment, the polyhedral calibration block in step S111 is a high-precision pyramid block with known precise dimensions.

[0045] This application employs high-precision pyramid blocks as polyhedral calibration blocks for system calibration, providing three-dimensional spatial constraints for each sensor. By scanning these inclined planes once, the coordinate transformation matrices of each 3D line laser sensor can be calculated simultaneously with high precision, greatly simplifying the calibration process, avoiding cumbersome multi-position calibration operations, and significantly improving efficiency and convenience. Its unique geometric structure ensures that an effective measurement surface can be obtained from any 3D line laser sensor perspective. Using high-precision registration with known dimensions and point cloud data, transformation parameters can be calculated directly and objectively, avoiding errors introduced by iterative optimization or manual alignment, thus ensuring the high precision and high reliability of the calibration parameters themselves. The final established preset system calibration parameters unify multi-sensor data into a stable and unique global coordinate system, fundamentally solving the benchmark problem of data fusion, providing a foundation for the subsequent establishment of a full-circumference point cloud model, and is key to ensuring the long-term measurement consistency and reliability of the system.

[0046] In some embodiments, after step S102 and before step S103, there is a step of converting the plurality of sets of three-dimensional point cloud data sets to a unified global coordinate system based on preset system calibration parameters.

[0047] This application unifies the spatial reference of multi-source heterogeneous data by uniformly transforming the data collected by each sensor to the global coordinate system based on preset calibration parameters, laying a solid foundation for subsequent high-precision data fusion in the global coordinate system. At the same time, it solidifies the complex spatial calibration relationship into reusable system parameters, avoiding online real-time calculation and significantly enhancing the system's processing efficiency and operational robustness. While ensuring measurement accuracy, it is adapted to the actual engineering needs of high-speed online detection.

[0048] In some embodiments, step S103 involves generating a full-circumference three-dimensional point cloud model representing the circumferential surface of the cylindrical structural member, such as... Figure 4 Includes the following steps: S1031, using the coordinate transformation matrix in the system calibration parameters, transform each set of three-dimensional point cloud data to the global coordinate system to complete the initial registration; S1032, Based on the geometric features of the overlapping regions of the transformed sets of three-dimensional point cloud data, an iterative nearest point algorithm is used for accurate registration; S1033, merge the several sets of precisely registered 3D point cloud datasets into a single, seamless full-circumference 3D point cloud model.

[0049] Specifically, it should be understood that, such as Figure 5 As shown, Figure 5 (a) Presents discrete, local point cloud fragments of calibration blocks collected by each sensor in an independent coordinate system. Figure 5 (b) A complete and continuous 3D model of the calibration block after the registration and fusion process is presented; Figure 5 (c) Presents a set of three-dimensional point cloud slices (i.e. several discontinuous circumferential arc segments) captured at the same time by multiple 3D line laser sensors in the sensor group, corresponding to a certain cross section of the cylindrical structure. Figure 5 (d) The full-circumference three-dimensional point cloud model of the circumferential surface of the complete enclosing structure generated after registration and fusion processing.

[0050] This application eliminates blind spots and data gaps between multiple sensors through systematic coordinate transformation and precise registration, achieving 360° seamless 3D data fusion. The generated full-circumference point cloud model lays a reliable data foundation for subsequent accurate calculations of parameters such as diameter and cylindricity, avoiding measurement deviations caused by local sampling or missing data. It achieves complete digital reconstruction of the outer surface morphology of structural components, not only improving the accuracy and reliability of dimensional measurements but also providing a directly operable 3D data model for the automatic detection and quantitative analysis of surface defects.

[0051] In some embodiments, the full circumference parameters mentioned in step S104 include the diameter and cylindricity of the cylindrical structural member; wherein, the diameter is set as the average value of the fitted circle diameters of each axial section in the full circumference three-dimensional point cloud model; and the cylindricity is set as the extreme difference between the distances between the reference cylindrical surface fitted by the full circumference three-dimensional point cloud model and each measurement point.

[0052] In a preferred embodiment, the calculation of the diameter of the cylindrical structural member is as follows: Figure 6 As shown, it includes the following steps: S1041, At multiple preset height positions from the bottom of the cylindrical structural member, point cloud data of multiple cross sections are extracted from the full circumference three-dimensional point cloud model along the axial direction of the cylindrical structural member. S1042, Perform circular fitting on the point cloud data of each cross-section, and calculate the diameter of the fitted circle corresponding to each cross-section; S1043, Perform statistical analysis on all the fitted circle diameters to obtain diameter measurement data including their mean, maximum, minimum and standard deviation; S1044, the average value of the fitted circle diameter is taken as the diameter measurement result of the cylindrical structure.

[0053] In a preferred embodiment, the circular fitting employs the least squares method.

[0054] In another preferred embodiment, the plurality of preset height positions include 5mm, 10mm, 15mm, 25mm, 47mm, 70mm, 85mm and 90mm from the bottom of the cylindrical structural member.

[0055] This application achieves high-precision and comprehensive characterization of the diameter features of structural components through multi-level quantitative analysis. Specifically, it first extracts cross-sectional point clouds at multiple key axial locations (e.g., 5mm, 10mm, 15mm, 25mm, 47mm, 70mm, 85mm, and 90mm from the bottom) of the full-circumference 3D point cloud model according to process requirements. Then, it uses the least squares method to perform optimal circular fitting on the point cloud of each cross-section to obtain the theoretical diameter value at each location. Finally, through statistical analysis of all fitted diameters, it not only uses the average value as the basis for determining the overall diameter of the structural component but also simultaneously outputs the maximum, minimum, and standard deviation, thus completing a comprehensive evaluation of diameter size, extreme deviations, and axial consistency in a single measurement. By fully utilizing the completeness advantage of the full-circumference 3D point cloud, it elevates traditional single-dimensional inspection to a deep quantitative diagnosis of manufacturing process consistency, significantly enhancing the accuracy of the inspection results.

[0056] In a preferred embodiment, the calculation of the cylindricity of the cylindrical structural member is as follows: Figure 7 As shown, it includes the following steps: S1141, Perform cylindrical surface fitting on the full-circumference three-dimensional point cloud model to obtain a reference cylindrical surface; S1142, Calculate the normal distance from all measurement points in the full circumference three-dimensional point cloud model to the reference cylindrical surface; S1143, determine the maximum and minimum values ​​among all the stated normal distances; S1144, calculate the difference between the maximum value and the minimum value to obtain the extreme difference in cylindricity of the cylindrical structural member.

[0057] In some embodiments, the cylindrical surface fitting employs the least squares method or the minimum region method.

[0058] This application achieves high-precision, full-surface quantitative evaluation of the overall shape error of cylindrical structural components by fitting the entire cylindrical surface based on a complete three-dimensional point cloud of the full circumference (e.g., using the least squares method or the minimum region method) and calculating the extreme difference of the normal distance from all surface points to the fitting reference surface. This overcomes the inherent limitations of traditional local measurement or two-dimensional cross-sectional roundness evaluation, which cannot characterize axial shape error. The evaluation results are scientific, objective, and traceable. At the same time, the fully automated calculation process can be seamlessly integrated into high-speed production lines, enabling 100% online full inspection of the key geometric tolerance of cylindricity. This provides crucial shape accuracy data support for improving the consistency of structural component manufacturing processes. The fitted reference cylindrical surface is closer to the real situation, and the evaluation results are more accurate.

[0059] In some embodiments, after step S103, the method further includes a step of using an optical filtering algorithm and a point cloud post-processing algorithm to identify and remove outlier noise points caused by reflection in the full-body 3D point cloud model for cloud filtering.

[0060] Specifically, it should be understood that at the hardware acquisition level, the laser emission power of the 3D line laser sensor and the camera exposure time can be dynamically adjusted through optical filtering algorithms to adapt to structural components with different surface reflectivity, thereby suppressing overexposure or signal saturation at the source and improving the quality of the original point cloud signal. At the software processing level, point cloud post-processing algorithms can be further used to purify the constructed full-circumference model. For example, the RANSAC algorithm can be used to robustly fit the point cloud according to the cylindrical geometry model and automatically identify and remove abnormal noise points that do not conform to the cylindrical geometry characteristics and are discretely distributed, caused by residual reflection, dust, or surface attachments. In addition, statistical filtering, radius filtering, and other methods can be combined to remove outliers far from the main point cloud group. This effectively overcomes the measurement fluctuations caused by differences in the surface condition of structural components. This ensures that subsequent calculations of parameters such as diameter and cylindricity are based on high-quality, high-cleanliness point cloud models, thus obtaining stable and accurate measurement results under various actual production conditions (such as structural components of different batches and different surface treatment processes).

[0061] In some embodiments, step S104, which involves determining whether the cylindrical structural component is qualified based on the total circumference parameter, is as follows: Figure 8 As shown, it includes the following steps: S1241, Determine whether the total circumference parameter meets the preset conditions; S1242a, When the total circumference parameter meets the preset conditions, the cylindrical structural component is qualified; S1242b, When the total circumference parameter does not meet the preset conditions, the cylindrical structural component is unqualified.

[0062] In a preferred embodiment, the preset condition is that the diameter measurement result of the cylindrical structural member is within the preset diameter acceptable tolerance range and the extreme difference of the cylindricity of the cylindrical structural member is less than or equal to the preset allowable cylindricity threshold.

[0063] Specifically, it should be understood that the specific values ​​of the preset conditions can be dynamically configured according to the model or specifications of the cylindrical structural component. The cylindrical structural component is deemed "qualified" only when both the diameter measurement result and the extreme difference in cylindricity meet their respective preset conditions. Subsequently, the qualified product flow can be triggered (e.g., green light release, entry to the next workstation), and the unique identifier (e.g., QR code) and all measurement data of the structural component are recorded, forming a traceable quality file. If any parameter does not meet its preset condition, the structural component is deemed "unqualified." At this time, an alarm (audio-visual prompt) can be triggered, and the control actuator (e.g., ejector, sorting arm) can be used to separate it to the non-qualified product area, and the type and value of the out-of-tolerance parameter are recorded in detail, providing direct basis for process diagnosis and equipment maintenance.

[0064] The full circumference detection method for cylindrical structural parts based on sensor arrays provided in this application can be integrated into automated production lines to achieve full automation of measurement, judgment, and data traceability. Through synchronous acquisition, system calibration, and data fusion using multiple 3D line laser sensors arranged in a ring, non-contact high-speed measurement of the outer surface of cylindrical structural parts with no blind spots (360°), fundamentally eliminating the dynamic errors and speed bottlenecks caused by traditional mechanical rotation scanning; by using a complete three-dimensional point cloud model of the full circumference for fitting and calculation, the measurement accuracy and repeatability of diameter and cylindricity are significantly better than local scanning methods, and local surface defects can be reliably identified; multi-sensor synchronization and filtering algorithms effectively suppress on-site vibration and reflection interference.

[0065] Example 2 This invention provides a full circumference detection system for cylindrical structural components based on a sensor array, such as... Figure 9 As shown, it includes the following modules: The instruction generation module, in response to a trigger signal that the cylindrical structural component reaches a preset measurement point, generates a synchronous acquisition instruction and sends it to the sensor group; wherein, the sensor group includes at least three 3D line laser sensors arranged in a ring around the circumference of the cylindrical structural component; The data acquisition module is used to control the sensor group to execute the synchronous acquisition command, and at the same time control the relative movement of the sensor group and the cylindrical structure to acquire several sets of three-dimensional point cloud data during the movement. The model generation module is used to generate a full-circumference three-dimensional point cloud model representing the circumferential surface of the cylindrical structural component based on the several sets of three-dimensional point cloud data. The detection module is used to calculate the full circumference parameters of the cylindrical structural component based on the full circumference three-dimensional point cloud model, so as to determine whether the cylindrical structural component is qualified based on the full circumference parameters.

[0066] In some embodiments, such as Figure 10 As shown, the system also includes the following modules: A calibration module is used to fix a polyhedral calibration block at a preset measurement station; control the sensor group to scan the polyhedral calibration block to obtain calibration point cloud datasets in each sensor coordinate system; obtain the coordinate transformation matrix from each sensor coordinate system to the global coordinate system based on the mapping relationship between the polyhedral calibration block and the calibration point cloud dataset; and establish preset system calibration parameters based on the coordinate transformation matrix. The coordinate transformation module is used to transform the several sets of three-dimensional point cloud data into a unified global coordinate system based on preset system calibration parameters.

[0067] This application discloses a sensor-based full-circumference inspection system for cylindrical structural components. Through the coordinated operation of an instruction generation module, data acquisition module, coordinate transformation module, model generation module, and inspection module, it forms a highly integrated and automated measurement closed loop. With a modular hardware and software architecture, this system achieves full-process automation from precise triggering, multi-source synchronous acquisition, unified data fusion, to intelligent analysis and judgment. It not only ensures the integrity and synchronization of 360° full-circumference 3D point cloud data acquisition but also provides a reliable data foundation for calculating key parameters such as diameter and cylindricity through strict coordinate unification and model fusion. Optimized design and collaboration among the system's modules effectively suppress external interference, significantly improving the repeatability and efficiency of inspection. It can be seamlessly integrated into high-speed production lines, achieving 100% online full inspection while providing a complete digital solution for process optimization and quality traceability, fully meeting the high-precision, high-cycle, and high-reliability inspection needs of the cylindrical structural component manufacturing industry.

[0068] Example 3 This invention also provides a computer-readable storage medium, such as... Figure 11 As shown, it stores program instructions, which, when executed, implement the full circumference detection method for cylindrical structures based on sensor arrays as described in Embodiment 1 above.

[0069] The program instructions are stored in a computer-readable storage medium (such as a CD-ROM, USB flash drive, or portable hard drive) or on a network, and include several computer program instructions to cause a computing device (such as a personal computer, server, or network device) to execute the above-described method according to the embodiments of this application.

[0070] Through the above description of the embodiments, those skilled in the art will readily understand that the exemplary embodiments described herein can be implemented by software or by combining software with necessary hardware. Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention, and other modifications can be easily made by those skilled in the art. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details and examples shown and described herein.

[0071] The apparatus, electronic device, and non-volatile computer storage medium and method provided in the embodiments of this specification are corresponding. Therefore, the apparatus, electronic device, and non-volatile computer storage medium also have similar beneficial technical effects as the corresponding method. Since the beneficial technical effects of the method have been described in detail above, the beneficial technical effects of the corresponding apparatus, electronic device, and non-volatile computer storage medium will not be repeated here.

[0072] Those skilled in the art will also know that, besides implementing the controller in the form of purely computer-readable program code, the same functions can be achieved by logically programming the method steps, making the controller take the form of logic gates, switches, application-specific integrated circuits (ASICs), programmable logic controllers (PLCs), and embedded microcontrollers. Therefore, such a controller can be considered a hardware component, and the devices included within it for implementing various functions can also be considered structures within that hardware component. Alternatively, the devices for implementing various functions can be considered as both software modules implementing the method and structures within a hardware component.

[0073] The systems, devices, modules, or units described in the above embodiments can be implemented by computer chips or entities, or by products with certain functions. A typical implementation device is a computer. Specifically, a computer can be, for example, a personal computer, laptop computer, cellular phone, camera phone, smartphone, personal digital assistant, media player, navigation device, email device, game console, tablet computer, wearable device, or any combination of these devices.

[0074] For ease of description, the above apparatus is described by dividing it into various functional units. Of course, when implementing one or more embodiments of this specification, the functions of each unit can be implemented in one or more software and / or hardware.

[0075] Those skilled in the art will understand that the embodiments of this specification can be provided as methods, systems, or computer program products. Therefore, the embodiments of this specification can take the form of entirely hardware embodiments, entirely software embodiments, or embodiments combining software and hardware aspects.

[0076] This specification is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this specification. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0077] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0078] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0079] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0080] Memory may include non-persistent storage in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0081] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0082] This specification can be described in the general context of computer-executable instructions that are executed by a computer, such as program modules. Generally, program modules include routines, programs, objects, components, data structures, etc., that perform a specific task or implement a specific abstract data type. This specification can also be practiced in distributed computing environments, where tasks are performed by remote processing devices connected via a communication network. In distributed computing environments, program modules can reside on local and remote computer storage media, including storage devices.

[0083] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, the system embodiments are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the descriptions in the method embodiments.

[0084] The above description is merely an embodiment of this specification and is not intended to limit the scope of one or more embodiments of this specification. Various modifications and variations can be made to one or more embodiments of this specification by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principle of one or more embodiments of this specification should be included within the scope of the claims of one or more embodiments of this specification.

Claims

1. A method for detecting the full circumference of a cylindrical structural component based on a sensor array, characterized in that, Specifically, the following steps are included: In response to a trigger signal that the cylindrical structural member reaches a preset measurement point, a synchronous acquisition command is generated and sent to the sensor group; wherein, the sensor group includes at least three 3D line laser sensors arranged in a ring around the circumference of the cylindrical structural member; The sensor group is controlled to execute the synchronous acquisition command, and the relative movement between the sensor group and the cylindrical structure is controlled to acquire several sets of three-dimensional point cloud data during the movement. A full-circumference three-dimensional point cloud model representing the circumferential surface of the cylindrical structural component is generated based on the aforementioned sets of three-dimensional point cloud data. Based on the full circumference three-dimensional point cloud model, the full circumference parameters of the cylindrical structural component are calculated, and the qualification of the cylindrical structural component is determined according to the full circumference parameters.

2. The method for detecting the full circumference of a cylindrical structure based on a sensor array according to claim 1, characterized in that, The total circumference parameters include the diameter and cylindricity of the cylindrical structural component.

3. The method for detecting the full circumference of a cylindrical structure based on a sensor array according to claim 2, characterized in that, Calculating the diameter of the cylindrical structural member includes the following steps: Point cloud data of multiple cross sections are extracted from the full circumference three-dimensional point cloud model at multiple preset height positions from the bottom of the cylindrical structural member, along the axial direction of the cylindrical structural member. For each of the point cloud data sections, a circular fit is performed to calculate the diameter of the fitted circle corresponding to each cross section. Statistical analysis was performed on all the fitted circle diameters to obtain diameter measurement data including their mean, maximum, minimum and standard deviation; The average value of the fitted circle diameter is used as the diameter measurement result of the cylindrical structure.

4. The method for detecting the full circumference of a cylindrical structure based on a sensor array according to claim 2, characterized in that, Calculating the cylindricity of the cylindrical structural component includes the following steps: A cylindrical surface is fitted to the full-circumference three-dimensional point cloud model to obtain a reference cylindrical surface; Calculate the normal distance from all measurement points in the full-circumference three-dimensional point cloud model to the reference cylindrical surface; Determine the maximum and minimum values ​​among all the stated normal distances; The difference between the maximum value and the minimum value is calculated to obtain the extreme difference in cylindricity of the cylindrical structural component.

5. The method for measuring the full circumference of a cylindrical structure of a sensor array according to claim 1, characterized in that, Before the step of generating the synchronous acquisition command, a system calibration step is also included: Fix the polyhedral calibration block at the preset measurement station; The sensor group is controlled to scan the polyhedral calibration block to obtain a calibration point cloud dataset in each sensor coordinate system; Based on the mapping relationship between the polyhedral calibration block and the calibration point cloud dataset, obtain the coordinate transformation matrix from each sensor coordinate system to the global coordinate system; Based on the coordinate transformation matrix, preset system calibration parameters are established.

6. The method for measuring the full circumference of a cylindrical structure of a sensor array according to claim 1, characterized in that, After generating the full-body 3D point cloud model, a point cloud filtering step is also included: Optical filtering and point cloud post-processing algorithms are used to identify and remove outlier noise points caused by reflection in the full-body 3D point cloud model.

7. The method for measuring the full circumference of a cylindrical structure of a sensor array according to claim 1, characterized in that, The step of generating a synchronous acquisition command in response to a trigger signal that the cylindrical structural member has reached a preset measurement point includes the following steps: The position of the cylindrical structural component is monitored in real time by a photoelectric sensor located at the preset measurement point. When the photoelectric sensor determines that the preset reference position of the cylindrical structural component has entered its effective detection area, it generates the trigger signal and transmits it to the main control unit. In response to the trigger signal, the synchronous acquisition command is generated based on the preset measurement timing.

8. The method for measuring the full circumference of a cylindrical structure of a sensor array according to claim 1, characterized in that, The process of generating a full-circumference three-dimensional point cloud model representing the circumferential surface of the cylindrical structural component includes the following steps: Using the coordinate transformation matrix in the system calibration parameters, the three-dimensional point cloud data sets of each group are transformed to the global coordinate system to complete the initial registration; Based on the geometric features of the overlapping regions of the transformed sets of three-dimensional point cloud data, an iterative nearest point algorithm is used for accurate registration. The several sets of precisely registered 3D point cloud datasets are merged into a single, seamless full-body 3D point cloud model.

9. A full circumference detection system for cylindrical structural components based on a sensor array, characterized in that, Includes the following modules: The instruction generation module, in response to a trigger signal that the cylindrical structural component reaches a preset measurement point, generates a synchronous acquisition instruction and sends it to the sensor group; wherein, the sensor group includes at least three 3D line laser sensors arranged in a ring around the circumference of the cylindrical structural component; The data acquisition module is used to control the sensor group to execute the synchronous acquisition command, and at the same time control the relative movement of the sensor group and the cylindrical structure to acquire several sets of three-dimensional point cloud data during the movement. The model generation module is used to generate a full-circumference three-dimensional point cloud model representing the circumferential surface of the cylindrical structural component based on the several sets of three-dimensional point cloud data. The detection module is used to calculate the full circumference parameters of the cylindrical structural component based on the full circumference three-dimensional point cloud model, so as to determine whether the cylindrical structural component is qualified based on the full circumference parameters.

10. A readable storage medium having a computer program stored thereon, characterized in that, The computer program is executed by a processor as described in any one of claims 1-8, the method for detecting the full circumference of a cylindrical structure based on a sensor array.

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