A high-precision laser position detection dynamic compensation method and system

Abstract

The application provides a high-precision laser position detection dynamic compensation method and system, and relates to the technical field of visual detection.The method part comprises the following steps: setting a fixed-length time window, collecting vibration interference related characteristic data of the equipment in each time window; preprocessing the collected vibration interference related characteristic data, and calculating and obtaining a vibration interference intensity index; constructing a light spot three-dimensional coordinate data set and a feature mark three-dimensional coordinate data set; constructing a conversion function, calculating a deviation index in the fixed time window; setting a vibration interference intensity threshold and a deviation threshold, and making a decision judgment on the compensation mode.The application can not only detect the position deviation size between the light spot and the target, but also further analyze whether the deviation is caused by external vibration interference or other non-vibration reasons, so that blind compensation or misjudgment is avoided, the deviation source can be distinguished, the compensation effect is improved, and misoperation is reduced.

Description

Technical Field

[0001] This invention relates to the field of industrial vision and visual measurement technology, specifically to a high-precision laser position detection dynamic compensation method and system that combines visual inspection techniques with visual intelligent analysis. Background Technology

[0002] During the dynamic compensation process of laser position detection, vibration interference can directly cause irregular fluctuations in the relative displacement between the laser spot and the target being detected. This results in random drift or periodic jitter in the acquired three-dimensional coordinates of the laser spot, leading the visual detection system to misjudge the target's movement as asynchronous, thus affecting the accuracy and stability of the compensation algorithm. Specific dynamic compensation for vibration can improve the anti-interference capability and synchronous tracking accuracy of laser position detection under complex working conditions.

[0003] In the prior art, patent CN113984028A discloses a laser gimbal tracking optical axis compensation method and system. This technology includes: acquiring a laser illumination image during the tracking process; determining the deviation between the tracking center position and the laser spot center position through image recognition; calculating the compensation amount when the laser spot center and target center positions meet the tracking accuracy requirements; and correcting the tracking center position based on the compensation amount to perform target tracking. The above prior art obtains the deviation between the tracking center position and the laser spot position through image recognition, and compensates for the tracking target position, causing the tracking center position to deviate from the tracking target so that the laser spot center coincides with the tracking target. This compensation of tracking deviation quickly achieves the compensation of the laser gimbal tracking optical axis, improving tracking accuracy. The determination of the compensation amount is achieved quickly and efficiently using a PID closed-loop control algorithm.

[0004] However, the aforementioned existing technologies only focus on the trajectory changes of the light spot itself or simply perform filtering and smoothing, and cannot effectively distinguish whether the root cause of the position deviation is external vibration interference or other non-vibration factors. Therefore, when deviation occurs, it is easy to blindly compensate or misjudge it as tracking error, without actively analyzing vibration characteristics. Such conventional solutions are prone to ineffective compensation, missing the opportunity to switch target models or reposition, and ultimately affecting the reliability of laser position detection and the adaptive capability of dynamic compensation.

[0005] The information disclosed in the background section is only intended to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0006] The purpose of this invention is to provide a high-precision laser position detection dynamic compensation method and system to solve the problems mentioned in the background art. This invention can not only detect the magnitude of the positional deviation between the laser spot and the target, but also further analyze whether the deviation is caused by external vibration interference or other non-vibration reasons, thereby avoiding blind compensation or misjudgment. It can distinguish the source of deviation, improve the compensation effect, and reduce operational errors.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] A high-precision laser position detection dynamic compensation method includes the following steps:

[0009] S1: Set a fixed-length time window, and collect vibration interference related characteristic data of the device in each time window. The vibration interference related characteristic data includes vibration displacement amplitude, amplitude ratio and maximum peak-to-peak value of vibration signal.

[0010] S2: Preprocess the collected vibration interference related feature data to remove DC components and high-frequency noise, perform normalization processing on the data in each time window, construct a weighting function, and calculate the vibration interference intensity index.

[0011] S3: Within a fixed time window, the three-dimensional coordinates of the laser spot on the target and the three-dimensional coordinates of the feature markers on the target are collected at a fixed frequency using visual detection technology, forming a laser spot three-dimensional coordinate dataset and a feature marker three-dimensional coordinate dataset, respectively.

[0012] S4: Construct a transformation function. Input the 3D coordinate dataset of the light spot and the 3D coordinate dataset of the feature markers into the transformation function to calculate the deviation index within a fixed time window.

[0013] S5: Set the vibration interference intensity threshold and the deviation threshold. When the deviation index is less than or equal to the deviation threshold, the current normal dynamic compensation mode is maintained. If the deviation index is greater than the deviation threshold, further comparison and judgment are performed: if the vibration interference intensity index is greater than the vibration interference intensity threshold, the main cause of the high deviation index is considered to be vibration. At this time, the enhanced vibration suppression compensation mode is switched and steps S1-S5 are re-executed. If the vibration interference intensity index is less than or equal to the vibration interference intensity threshold, it indicates that the main cause of the high deviation index is not vibration.

[0014] Furthermore, the acquisition process for the vibration disturbance-related characteristic data in S1 includes:

[0015] The method for obtaining the vibration displacement amplitude is as follows: by detecting the original waveform of the relative displacement caused by vibration changing with time, after baseline correction of the waveform, the peak displacement in each vibration cycle is extracted. The peak displacement is the maximum value of the absolute value of the displacement in each vibration cycle. The average value of all peak displacements in the current time window is taken as the vibration displacement amplitude of the corresponding time window.

[0016] The method for obtaining the amplitude ratio is as follows: based on the spectrum analysis of the vibration signal, perform a fast Fourier transform on the displacement or acceleration time-domain data within the window to obtain the amplitude spectrum of each frequency component, find the dominant frequency component with the largest amplitude, and calculate the ratio of the dominant frequency amplitude to the sum of the amplitudes of all frequency components as the amplitude ratio of the corresponding time window, which is used to characterize whether the vibration energy is concentrated on a specific frequency.

[0017] The method for obtaining the maximum peak-to-peak value of the vibration signal is as follows: from the preprocessed displacement or acceleration signal, find the difference between the maximum and minimum values ​​of the waveform within the current time window, and record the difference as the maximum peak-to-peak value of the vibration signal.

[0018] Furthermore, the formula for normalizing the data within each time window in S2 is as follows:

[0019]

[0020] in:

[0021] This represents the original value at the i-th sampling moment within a fixed time window after bandpass filtering.

[0022] This represents the minimum value among all sampling points within the current time window. Let f(x) be the maximum value among all sampling points in the current time window, and satisfy the condition that f(x) = ... ;

[0023] The value at the i-th sampling time is the normalized value;

[0024] when hour, .

[0025] Furthermore, the formula used to calculate the vibration disturbance intensity index is as follows:

[0026]

[0027] in:

[0028] VII represents the vibration disturbance intensity index;

[0029] AMP represents the pre-processed vibration displacement amplitude;

[0030] This serves as a reference value for the vibration displacement amplitude.

[0031] RAT represents the preprocessed amplitude percentage.

[0032] PKP is the maximum peak-to-peak value of the preprocessed vibration signal;

[0033] This serves as a reference value for the maximum peak-to-peak value of the vibration signal.

[0034] α, β, and γ are the weighting coefficients of vibration displacement amplitude, amplitude ratio, and maximum peak-to-peak value of vibration signal, respectively. α, β, and γ are all non-negative real numbers and satisfy α+β+γ=1 and β<α≤γ.

[0035] Furthermore, the method for establishing the three-dimensional coordinate dataset of the light spot and the three-dimensional coordinate dataset of the feature label in S3 includes:

[0036] Determine the fixed sampling frequency f, calculate the total number of samplings N = f × T within the fixed time window T, and set the sampling time within the fixed time window T as... Then the adjacent sampling interval ;

[0037] At each sampling time The coordinates of the center point of the laser spot formed on the surface of the target are obtained in three-dimensional space and denoted as follows: And obtain the three-dimensional coordinates of the pre-set feature markers on the detection target in the same spatial coordinate system, denoted as The feature marker is fixed to the detection target and has no relative movement with the detection target.

[0038] Furthermore, the three-dimensional coordinates of the light spots obtained at all sampling times are arranged in chronological order to form a dataset of three-dimensional coordinates of the light spots:

[0039]

[0040] The three-dimensional coordinate dataset of the light spot is used to reflect the trajectory changes of the light spot within the time window as it moves in space and as a possible target.

[0041] Arrange the 3D coordinates of the feature labels obtained at all sampling times in the same temporal order to form a dataset of 3D coordinates of the feature labels:

[0042]

[0043] The feature-labeled 3D coordinate dataset is used to reflect the pose changes of the detected target itself within a time window.

[0044] Furthermore, the formula used to calculate the deviation index within the fixed time window is as follows:

[0045]

[0046] in:

[0047] DI stands for Deviation Index;

[0048] Let be the three-dimensional coordinate vector of the light spot at the i-th sampling time, i.e. ;

[0049] The feature at the i-th sampling time is labeled with a three-dimensional coordinate vector, i.e. ;

[0050] This is the mean of all instantaneous relative displacement vectors within the time window. ,and Let be the instantaneous relative displacement vector of the light spot with respect to the feature marker at the i-th sampling time.

[0051] It is a distance function in three-dimensional space.

[0052] Furthermore, in step S5, the logic for comparing the calculated vibration disturbance intensity index, deviation index, vibration disturbance intensity threshold, and deviation threshold is as follows:

[0053] when When the laser spot is determined to be in good synchronization with the target motion and there is no significant deviation, the current conventional dynamic compensation mode is maintained and there is no need to analyze the cause of vibration.

[0054] when and If the deviation index exceeds the standard and the vibration interference intensity index exceeds the vibration interference intensity threshold, the primary cause is considered to be vibration interference. At this time, switch to enhanced vibration suppression compensation mode, re-collect data and evaluate.

[0055] when and If the deviation index exceeds the standard, but the vibration interference intensity index does not exceed the vibration interference intensity threshold, then position detection is stopped and the target model is switched or laser repositioning is triggered.

[0056] in, These are the deviation threshold and the vibration disturbance intensity threshold, respectively.

[0057] Furthermore, the process for obtaining the deviation threshold includes: establishing an ideal working condition with no significant vibration and synchronized motion; collecting relative displacement data sequences between light spots and feature markers within multiple time windows; calculating the deviation index for each window; statistically analyzing its distribution characteristics; and taking the deviation threshold as the 90%-95% quantile of historical data.

[0058] The process for obtaining the vibration interference intensity threshold includes: under ideal working conditions with no significant vibration and synchronous motion, synchronously collecting vibration interference related feature data, calculating the vibration interference intensity index of each time window according to the weighting function in S2, and taking the upper quartile value of all time windows as the vibration interference intensity threshold.

[0059] A high-precision laser position detection dynamic compensation system, the compensation system being used to execute the above-described compensation method, the compensation system comprising the following functional modules:

[0060] Vibration interference data acquisition module: Set a fixed-length time window, and collect vibration interference related characteristic data of the device in each time window. The vibration interference related characteristic data includes vibration displacement amplitude, amplitude ratio and maximum peak-to-peak value of vibration signal.

[0061] Interference intensity analysis module: preprocesses the collected vibration interference related feature data, removes DC components and high-frequency noise through a bandpass filter, performs normalization processing on the data in each time window, constructs a weighting function, and calculates and obtains the vibration interference intensity index;

[0062] The laser spot and marker synchronous acquisition module: within a fixed time window, the three-dimensional coordinates of the laser spot on the target and the three-dimensional coordinates of the feature markers on the target are acquired at a fixed frequency using visual detection technology, forming a laser spot three-dimensional coordinate dataset and a feature marker three-dimensional coordinate dataset, respectively.

[0063] Motion Deviation Index Calculation Module: Constructs a transformation function, which is used to calculate the deviation index within a fixed time window by inputting the three-dimensional coordinate dataset of the light spot and the three-dimensional coordinate dataset of the feature marker.

[0064] Dynamic compensation decision and switching module: Set vibration interference intensity threshold and deviation threshold. When the deviation index is less than or equal to the deviation threshold, the current normal dynamic compensation mode is maintained. If the deviation index is greater than the deviation threshold, further comparison and judgment are performed: If the vibration interference intensity index is greater than the vibration interference intensity threshold, it indicates that the main cause of the high deviation index is vibration. At this time, switch to enhanced vibration suppression compensation mode and re-perform compensation decision; If the vibration interference intensity index is less than or equal to the vibration interference intensity threshold, it indicates that the main cause of the high deviation index is not vibration.

[0065] Compared with the prior art, the beneficial effects of the present invention are:

[0066] This invention can not only detect the magnitude of the positional deviation between the light spot and the target, but also further analyze whether the deviation is caused by external vibration interference or other non-vibration reasons, thus avoiding blind compensation or misjudgment. It comprehensively collects vibration characteristics from multiple dimensions, such as vibration displacement amplitude, vibration energy concentration, and maximum fluctuation range, and calculates a vibration interference intensity index. Then, it combines the relative displacement fluctuation between the light spot and the feature mark fixed on the target to obtain a deviation index. In this way, it can intelligently determine the main cause when the deviation exceeds the standard: if the vibration is too large, it automatically switches to the enhanced vibration suppression compensation mode and re-detects; if the vibration is normal but the deviation still exceeds the standard, it means that the problem is not in the vibration. At this time, it will stop the conventional compensation and actively switch the target model or trigger laser repositioning, so as to distinguish the source of the deviation, improve the compensation effect, and reduce misoperation. Attached Figure Description

[0067] Figure 1 This is a flowchart of a high-precision laser position detection dynamic compensation method according to the present invention;

[0068] Figure 2 This is a schematic diagram of a high-precision laser position detection dynamic compensation system according to the present invention. Detailed Implementation

[0069] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments.

[0070] It should be noted that, unless otherwise defined, the technical or scientific terms used in this invention should have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0071] Example:

[0072] Please see Figures 1-2 The present invention provides the following technical solutions:

[0073] A high-precision laser position detection dynamic compensation method is provided. This method can be integrated into intelligent control systems for unmanned material handling yards to improve the laser positioning and target tracking capabilities of equipment such as stacker-reclaimers and conveyor belts in complex vibration environments. Furthermore, this invention is not only applicable to conventional laser detection scenarios but can also be extended to other unlisted general equipment manufacturing industries, such as laser rapid prototyping equipment, providing highly vibration-resistant closed-loop feedback for laser spot position in processes such as metal additive manufacturing and laser cladding. The specific steps include:

[0074] S1: Set a fixed-length time window, the length of which is pre-calibrated based on the vibration characteristics and actual operating conditions of the equipment. Within each time window, the system continuously collects characteristic data related to equipment vibration interference, specifically including vibration displacement amplitude, amplitude ratio, and maximum peak-to-peak value of the vibration signal. These data comprehensively reflect vibration intensity, energy concentration, and instantaneous impact characteristics, providing a basis for subsequent judgment on whether vibration has an unreliable impact on laser position detection.

[0075] The acquisition process for various vibration disturbance-related characteristic data includes:

[0076] By detecting the original waveform of the relative displacement caused by vibration changing continuously over time, the waveform is first subjected to baseline correction to eliminate the interference of zero-point drift and low-frequency trend terms, thereby obtaining a more realistic displacement change curve. Based on this, the peak displacement within each complete vibration cycle is identified and extracted one by one; the peak displacement is the maximum absolute value of the displacement within each vibration cycle. To reduce the impact of random fluctuations or single abnormal impacts on the evaluation results, the arithmetic mean of all extracted peak displacements within the current time window is taken. This average value is used as the vibration displacement amplitude corresponding to that time window to characterize the overall intensity level of the vibration during the window period.

[0077] The method for obtaining the amplitude proportion is as follows: Based on the spectral analysis of the vibration signal, a fast Fourier transform is performed on the displacement time-domain data or acceleration time-domain data collected within the current time window to convert them from the time domain to the frequency domain, obtaining the amplitude spectrum corresponding to each frequency component. The frequency component with the largest amplitude is searched and located in the amplitude spectrum; this component is the dominant frequency component. The proportion of the amplitude of this dominant frequency component to the sum of the amplitudes of all frequency components is further calculated, and this proportion is used as the amplitude proportion for the corresponding time window.

[0078] The method for obtaining the maximum peak-to-peak value of the vibration signal is as follows: In the displacement or acceleration signal after preprocessing, for the waveform data within the current time window, traverse the entire waveform and find its maximum and minimum values, then calculate the difference between the two, i.e., the vertical distance between the peak and trough. Record this difference as the maximum peak-to-peak value of the vibration signal for that time window.

[0079] S2: The collected vibration interference-related feature data undergoes systematic preprocessing. First, bandpass filtering effectively removes DC components and high-frequency noise from the signal, ensuring signal quality for subsequent analysis. Based on this, normalization is performed on the data within each time window, transforming feature data with different dimensions and amplitude ranges to the same scale interval, eliminating numerical differences caused by different feature sources. According to the varying degrees of influence of each feature on vibration interference, a weighting function is constructed, assigning corresponding weights to vibration displacement amplitude, amplitude proportion, and the maximum peak-to-peak value of the vibration signal. A comprehensive vibration interference intensity index is calculated through weighted fusion to quantitatively assess the overall severity of vibration interference within the current time window.

[0080] The formula for normalizing the data within each time window is:

[0081]

[0082] in:

[0083] This represents the original value of the i-th sampling point within a fixed time window after bandpass filtering.

[0084] This represents the minimum value among all sampling points within the current time window. Let f(x) be the maximum value among all sampling points in the current time window, and satisfy the condition that f(x) = ... ;

[0085] The value of the i-th sampling point after normalization;

[0086] when hour, .

[0087] The formula used to calculate the vibration disturbance intensity index is as follows:

[0088]

[0089] in:

[0090] VII represents the vibration disturbance intensity index;

[0091] AMP represents the pre-processed vibration displacement amplitude, and AMP is positively correlated with VII. Under otherwise unchanged conditions, a larger AMP indicates a greater displacement of the equipment or target from its equilibrium position under vibration, resulting in more severe interference with laser position detection; therefore, VII will increase accordingly.

[0092] This serves as a reference value for the vibration displacement amplitude, which is a typical vibration displacement amplitude measured under ideal, non-significant vibration conditions, and is used as a normalization benchmark. Through... Convert the actual amplitude to a multiple relative to the normal level to make VII comparable between different operating conditions or different equipment;

[0093] RAT represents the preprocessed amplitude percentage, and RAT is also positively correlated with VII. This is because periodic vibrations with more concentrated energy are more likely to resonate with the sampling frequency of the detection system or the natural frequency of the structure, leading to regular deviations in the spot coordinate measurement and thus exacerbating the instability of position detection.

[0094] PKP is the peak-to-peak value of the preprocessed vibration signal, and PKP is positively correlated with VII. Even if the average displacement amplitude AMP is not large, if there is a large impact (such as equipment collision or external impact), PKP will increase significantly. This instantaneous large fluctuation may cause serious outliers in the laser spot coordinates at a single sampling point, which in turn causes the deviation index to soar.

[0095] This is the reference value for the maximum peak-to-peak value of the vibration signal. It is a typical peak-to-peak value measured under ideal working conditions and is used for normalization. This indicates that there are drastic fluctuations within the current window that are outside the normal range;

[0096] α, β, and γ are the weighting coefficients of vibration displacement amplitude, amplitude ratio, and maximum peak-to-peak value of vibration signal, respectively, and α, β, and γ are all non-negative real numbers, satisfying α+β+γ=1.

[0097] In this embodiment, AMP reflects the main energy level of vibration and is the core indicator of persistent interference. Therefore, α is usually set to a value that is not less than γ but not excessively greater than γ. It reflects the fundamental role of the average amplitude in the overall evaluation. RAT itself is a ratio between 0 and 1, and its influence often needs to be combined with other parameters (such as AMP or PKP) to be fully reflected. A high RAT alone but a very small amplitude may not necessarily cause serious actual interference. PKP is very sensitive to abrupt changes and shocks, and such interference is often more destructive to laser position detection than the periodic average amplitude (for example, it may directly cause the spot to miss the target). Therefore, γ is set to the largest among all weights. So, the following condition should be met: β < α ≤ γ.

[0098] S3: Within a pre-defined fixed time window, two sets of three-dimensional spatial coordinate data are synchronously acquired at a fixed sampling frequency using AI vision and industrial vision technologies. A visual intelligence algorithm assists in identifying the center of the laser spot and feature markers: one set consists of the three-dimensional coordinates of the center point of the laser spot when it is projected onto the surface of the target; the other set consists of the three-dimensional coordinates of pre-set feature markers on the target in the same spatial coordinate system. By continuously acquiring these coordinate information throughout the entire time window, the laser spot coordinates and feature marker coordinates are organized according to the acquisition time sequence, thus forming a laser spot three-dimensional coordinate dataset and a feature marker three-dimensional coordinate dataset.

[0099] In industrial food processing and intelligent manufacturing equipment, such as high-speed packaging lines or sorting robot systems, lasers are often used for precise positioning guidance. However, equipment start-up and shutdown, as well as conveyor belt vibration, can interfere with detection accuracy. The method of this invention is also applicable in such scenarios.

[0100] Methods for establishing 3D coordinate datasets of light spots and 3D coordinate datasets of feature labels include:

[0101] Determine a fixed sampling frequency f, which should be sufficient to capture the dynamic changes of the light spot and feature markers within the time window. Calculate the total number of samplings N = f × T within the fixed time window T, and set the sampling time within the fixed time window T as... Then the adjacent sampling interval ;

[0102] At each sampling time The coordinates of the center point of the laser spot formed on the surface of the target are obtained in three-dimensional space and denoted as follows: And obtain the three-dimensional coordinates of the pre-set feature markers on the detection target in the same spatial coordinate system, denoted as The feature marker is fixed on the detection target and there is no relative movement between them. Therefore, its coordinate changes completely reflect the pose changes of the detection target itself.

[0103] Arrange the three-dimensional coordinates of the light spot obtained at all sampling times in chronological order to form a dataset of the three-dimensional coordinates of the light spot:

[0104]

[0105] The three-dimensional coordinate dataset of the light spot is used to reflect the trajectory changes of the light spot within the time window as it moves in space and as a possible target.

[0106] Arrange the 3D coordinates of the feature labels obtained at all sampling times in the same temporal order to form a dataset of 3D coordinates of the feature labels:

[0107]

[0108] The feature-labeled 3D coordinate dataset is used to reflect the pose changes of the detected target itself within a time window.

[0109] S4: Construct a transformation function, taking the three-dimensional coordinate dataset of the light spot and the three-dimensional coordinate dataset of the feature marker as input. By analyzing the relative positional relationship between the light spot and the feature marker at each sampling time, comprehensively evaluate the degree of offset fluctuation between the two within the entire time window, and finally calculate a deviation index that can quantitatively characterize the magnitude of the positional deviation between the light spot and the target within the time window. The coordinate dataset of the light spot and the feature marker obtained by the high-precision visual measurement method provides reliable raw data support for the deviation index calculation in this step.

[0110] The formula used to calculate the deviation index within a fixed time window is:

[0111]

[0112] in:

[0113] DI stands for Deviation Index;

[0114] Let be the three-dimensional coordinate vector of the light spot at the i-th sampling time, i.e. The changes in this directly affect the laser's position (DI). If the spot position shifts additionally relative to the feature marker due to laser jitter, optical path disturbance, or changes in the reflectivity of the target surface, then... This will change accordingly, thereby increasing the difference between the sampling point and the average relative displacement. The difference in position leads to an increase in DI (Displacement Indicator). If the target changes pose due to external motion or its own vibration, and the laser spot fails to follow synchronously (e.g., the laser is stationary while the target moves), then... This will change accordingly, causing DI to increase. Therefore, Unexpected fluctuations can also cause DI to be positively correlated;

[0115] The feature at the i-th sampling time is labeled with a three-dimensional coordinate vector, i.e. If the target changes pose due to external motion or its own vibration, and the laser spot fails to follow synchronously (e.g., the laser is stationary while the target moves), then This will change accordingly, causing DI to increase. Therefore, Unexpected fluctuations can also cause DI to be positively correlated;

[0116] This is the mean of all instantaneous relative displacement vectors within the time window. ,and Let be the instantaneous relative displacement vector of the light spot relative to the feature marker at the i-th sampling time. This is the core variable for calculating DI. DI is actually all... Around its mean The root mean square variability. The greater the fluctuation amplitude (i.e., the greater the difference in relative displacement at different sampling times), the higher the DI value. Therefore, The variance is positively correlated with DI;

[0117] It is a distance function in three-dimensional space, used to calculate the length of a three-dimensional vector, that is, the spatial distance from the origin to the endpoint of the vector.

[0118] S5: Pre-set vibration interference intensity threshold and deviation threshold. These two thresholds are used to determine whether the vibration interference is significant and whether the positional deviation between the light spot and the target is within the allowable range, respectively. In the actual detection process, the calculated deviation index is first compared with the deviation threshold: when the deviation index is less than or equal to the deviation threshold, it indicates that the light spot and the detected target are well synchronized in the current time window, and the positional deviation is within an acceptable range. At this time, the system continues to operate in the original conventional dynamic compensation mode without additional adjustment.

[0119] Taking food industrial processing and intelligent manufacturing equipment as an example, when the deviation index exceeds the standard but the vibration interference intensity index is normal, the system will actively stop the routine compensation and trigger laser repositioning, thereby avoiding product miscutting or missed detection due to target model failure.

[0120] If the deviation index is greater than the deviation threshold, it means that the position deviation has exceeded the normal range. At this time, it is necessary to proceed to the further comparison and judgment stage, that is, to conduct a comprehensive analysis by combining the vibration interference intensity index and the vibration interference intensity threshold.

[0121] Specifically, if the vibration interference intensity index is greater than the vibration interference intensity threshold, it is determined that the main reason for the high deviation index is likely vibration interference. In this case, the system should prioritize vibration factors, actively switch to the enhanced vibration suppression compensation mode, and restart the entire detection and compensation process from step S1 to suppress the adverse effects of vibration. Conversely, if the vibration interference intensity index is less than or equal to the vibration interference intensity threshold, it indicates that vibration is not the main factor causing the high deviation index, and it should be considered that there are other non-vibration interference sources causing abnormal position deviation.

[0122] The logic for comparing the calculated vibration disturbance intensity index, deviation index, vibration disturbance intensity threshold, and deviation threshold is as follows:

[0123] when When the time is right, it indicates that the motion synchronization between the laser spot and the detection target is good within the current time window, and the relative position deviation between the two is within an acceptable normal range without significant abnormal deviation. At this time, the system does not need to perform vibration cause analysis and can continue to maintain the current conventional dynamic compensation mode.

[0124] when and If the positional deviation within the current time window exceeds the allowable range, and the vibration interference intensity also significantly exceeds the normal level, then the main reason for the deviation index exceeding the standard is vibration interference. The system should prioritize vibration factors, immediately switch to enhanced vibration suppression compensation mode, and restart data acquisition and subsequent evaluation to suppress the negative impact of vibration.

[0125] when and If the position deviation exceeds the standard, it means that the vibration interference intensity has not exceeded the normal threshold. Therefore, vibration is not the main reason for the high deviation. At this time, the system should stop the current position detection and switch the target model or trigger the laser repositioning operation to eliminate interference from other non-vibration factors.

[0126] in, These are the deviation threshold and the vibration interference intensity threshold, respectively, serving as two key judgment criteria in the above comparison logic.

[0127] The process for obtaining the deviation threshold includes: establishing an ideal working environment without significant vibration interference and where the laser spot moves synchronously with the target; continuously acquiring relative displacement data sequences between the laser spot and the feature marker within multiple time windows under this condition; then independently calculating the deviation index for each time window to obtain a set of sample data reflecting the deviation fluctuation level under ideal conditions; next, statistically analyzing the overall distribution characteristics of this batch of deviation indices, specifically calculating their percentile distribution in this embodiment; and finally, using the value corresponding to the 95th percentile in the historical data as the deviation threshold, ensuring that under normal working conditions, the deviation index may exceed this threshold in only 5% of the time windows, thus providing a reasonable reference limit for subsequent determination of whether a significant deviation has occurred.

[0128] The process for obtaining the vibration interference intensity threshold includes: under identical ideal operating conditions, synchronously collecting vibration interference-related characteristic data within each time window, including vibration displacement amplitude, amplitude ratio, and maximum peak-to-peak value of the vibration signal. Then, according to the weighting function constructed in step S2, calculate the vibration interference intensity index for each time window to obtain a sample of vibration interference intensity index under ideal operating conditions. Finally, take the upper quartile value of all these samples, i.e., the 75th percentile after data sorting, as the vibration interference intensity threshold to distinguish between normal vibration fluctuations and abnormal vibration interference levels that require attention.

[0129] A high-precision laser position detection dynamic compensation system, the compensation system being used to execute the above-described compensation method, the compensation system comprising the following functional modules:

[0130] Vibration interference data acquisition module: Set a fixed-length time window, and collect vibration interference related characteristic data of the device in each time window. The vibration interference related characteristic data includes vibration displacement amplitude, amplitude ratio and maximum peak-to-peak value of vibration signal.

[0131] Interference intensity analysis module: preprocesses the collected vibration interference related feature data, removes DC components and high-frequency noise through a bandpass filter, performs normalization processing on the data in each time window, constructs a weighting function, and calculates and obtains the vibration interference intensity index;

[0132] The laser spot and marker synchronous acquisition module: within a fixed time window, through industrial vision and visual inspection technology, combined with visual intelligent target recognition algorithm, the three-dimensional coordinates of the laser spot on the detection target and the three-dimensional coordinates of the feature marker on the detection target are acquired at a fixed frequency, forming a laser spot three-dimensional coordinate dataset and a feature marker three-dimensional coordinate dataset respectively.

[0133] Motion Deviation Index Calculation Module: Constructs a transformation function, which is used to calculate the deviation index within a fixed time window by inputting the three-dimensional coordinate dataset of the light spot and the three-dimensional coordinate dataset of the feature marker.

[0134] Dynamic compensation decision and switching module: Set vibration interference intensity threshold and deviation threshold. When the deviation index is less than or equal to the deviation threshold, the current normal dynamic compensation mode is maintained. If the deviation index is greater than the deviation threshold, further comparison and judgment are performed: If the vibration interference intensity index is greater than the vibration interference intensity threshold, it indicates that the main cause of the high deviation index is vibration. At this time, switch to enhanced vibration suppression compensation mode and re-perform compensation decision; If the vibration interference intensity index is less than or equal to the vibration interference intensity threshold, it indicates that the main cause of the high deviation index is not vibration.

[0135] The above formulas are all dimensionless calculations. The formulas are derived from software simulations based on a large amount of collected data to obtain the most recent real-world results. The preset parameters in the formulas are set by those skilled in the art according to the actual situation.

[0136] The above embodiments can be implemented, in whole or in part, by software, hardware, firmware, or any other combination thereof. When implemented in software, the above embodiments can be implemented, in whole or in part, as a computer program product. Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution.

[0137] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0138] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application.

Claims

1. A high-precision laser position detection dynamic compensation method, characterized in that, Includes the following steps: S1: Set a fixed-length time window, and collect vibration interference related characteristic data of the device in each time window. The vibration interference related characteristic data includes vibration displacement amplitude, amplitude ratio and maximum peak-to-peak value of vibration signal. S2: Preprocess the collected vibration interference related feature data to remove DC components and high-frequency noise, perform normalization processing on the data in each time window, construct a weighting function, and calculate the vibration interference intensity index. S3: Within a fixed time window, the three-dimensional coordinates of the laser spot on the target and the three-dimensional coordinates of the feature markers on the target are collected at a fixed frequency using visual detection technology, forming a laser spot three-dimensional coordinate dataset and a feature marker three-dimensional coordinate dataset, respectively. S4: Construct a transformation function. Input the 3D coordinate dataset of the light spot and the 3D coordinate dataset of the feature markers into the transformation function to calculate the deviation index within a fixed time window. S5: Set the vibration interference intensity threshold and the deviation threshold. When the deviation index is less than or equal to the deviation threshold, the current normal dynamic compensation mode is maintained. If the deviation index is greater than the deviation threshold, further comparison and judgment are performed: if the vibration interference intensity index is greater than the vibration interference intensity threshold, the main cause of the high deviation index is considered to be vibration. At this time, the enhanced vibration suppression compensation mode is switched and steps S1-S5 are re-executed. If the vibration interference intensity index is less than or equal to the vibration interference intensity threshold, it indicates that the main cause of the high deviation index is not vibration.

2. The high-precision laser position detection dynamic compensation method according to claim 1, characterized in that: The acquisition process for the vibration disturbance-related characteristic data in S1 includes: The method for obtaining the vibration displacement amplitude is as follows: by detecting the original waveform of the relative displacement caused by vibration changing with time, after baseline correction of the waveform, the peak displacement in each vibration cycle is extracted. The peak displacement is the maximum value of the absolute value of the displacement in each vibration cycle. The average value of all peak displacements in the current time window is taken as the vibration displacement amplitude of the corresponding time window. The method for obtaining the amplitude ratio is as follows: based on the spectrum analysis of the vibration signal, perform a fast Fourier transform on the displacement or acceleration time-domain data within the window to obtain the amplitude spectrum of each frequency component, find the dominant frequency component with the largest amplitude, and calculate the ratio of the dominant frequency amplitude to the sum of the amplitudes of all frequency components as the amplitude ratio of the corresponding time window, which is used to characterize whether the vibration energy is concentrated on a specific frequency. The method for obtaining the maximum peak-to-peak value of the vibration signal is as follows: from the preprocessed displacement or acceleration signal, find the difference between the maximum and minimum values ​​of the waveform within the current time window, and record the difference as the maximum peak-to-peak value of the vibration signal.

3. The high-precision laser position detection dynamic compensation method according to claim 1, characterized in that: The formula for normalizing the data within each time window in S2 is as follows: in: This represents the original value at the i-th sampling moment within a fixed time window after bandpass filtering. This represents the minimum value among all sampling points within the current time window. Let f(x) be the maximum value among all sampling points in the current time window, and satisfy the condition that f(x) = ... ; The value at the i-th sampling time is the normalized value; when hour, .

4. The high-precision laser position detection dynamic compensation method according to claim 3, characterized in that: The formula used to calculate the vibration disturbance intensity index is as follows: in: VII represents the vibration disturbance intensity index; AMP represents the pre-processed vibration displacement amplitude; This serves as a reference value for the vibration displacement amplitude. RAT represents the preprocessed amplitude percentage. PKP is the maximum peak-to-peak value of the preprocessed vibration signal; This serves as a reference value for the maximum peak-to-peak value of the vibration signal. α, β, and γ are the weighting coefficients of vibration displacement amplitude, amplitude ratio, and maximum peak-to-peak value of vibration signal, respectively. α, β, and γ are all non-negative real numbers and satisfy α+β+γ=1 and β<α≤γ.

5. The high-precision laser position detection dynamic compensation method according to claim 1, characterized in that: The methods for establishing the three-dimensional coordinate dataset of the light spot and the three-dimensional coordinate dataset of the feature label in S3 include: Determine the fixed sampling frequency f, calculate the total number of samplings N = f × T within the fixed time window T, and set the sampling time within the fixed time window T as... Then the adjacent sampling interval ; At each sampling time The coordinates of the center point of the laser spot formed on the surface of the target are obtained in three-dimensional space and denoted as follows: And obtain the three-dimensional coordinates of the pre-set feature markers on the detection target in the same spatial coordinate system, denoted as The feature marker is fixed to the detection target and has no relative movement with the detection target.

6. The high-precision laser position detection dynamic compensation method according to claim 5, characterized in that: Arrange the three-dimensional coordinates of the light spot obtained at all sampling times in chronological order to form a dataset of the three-dimensional coordinates of the light spot: The three-dimensional coordinate dataset of the light spot is used to reflect the trajectory changes of the light spot within a time window as it moves in space and as a possible target. Arrange the 3D coordinates of the feature labels obtained at all sampling times in the same temporal order to form a dataset of 3D coordinates of the feature labels: The feature-labeled 3D coordinate dataset is used to reflect the pose changes of the detected target itself within a time window.

7. The high-precision laser position detection dynamic compensation method according to claim 6, characterized in that: The formula used to calculate the deviation index within the fixed time window is as follows: in: DI stands for Deviation Index; Let be the three-dimensional coordinate vector of the light spot at the i-th sampling time, i.e. ; The feature at the i-th sampling time is labeled with a three-dimensional coordinate vector, i.e. ; This is the mean of all instantaneous relative displacement vectors within the time window. ,and Let be the instantaneous relative displacement vector of the light spot with respect to the feature marker at the i-th sampling time. It is a distance function in three-dimensional space.

8. The high-precision laser position detection dynamic compensation method according to claim 1, characterized in that: In step S5, the logic for comparing the calculated vibration disturbance intensity index, deviation index, vibration disturbance intensity threshold, and deviation threshold is as follows: when When the laser spot is determined to be in good synchronization with the target motion and there is no significant deviation, the current conventional dynamic compensation mode is maintained and there is no need to analyze the cause of vibration. when and If the deviation index exceeds the standard and the vibration interference intensity index exceeds the vibration interference intensity threshold, the primary cause is considered to be vibration interference. At this time, switch to enhanced vibration suppression compensation mode, re-collect data and evaluate. when and If the deviation index exceeds the standard, but the vibration interference intensity index does not exceed the vibration interference intensity threshold, then position detection is stopped and the target model is switched or laser repositioning is triggered. in, These are the deviation threshold and the vibration disturbance intensity threshold, respectively.

9. The high-precision laser position detection dynamic compensation method according to claim 8, characterized in that: The process for obtaining the deviation threshold includes: establishing an ideal working condition with no significant vibration and synchronous motion; collecting relative displacement data sequences between light spots and feature markers within multiple time windows; calculating the deviation index for each window; statistically analyzing its distribution characteristics; and taking the deviation threshold as the 90%-95% quantile of historical data. The process for obtaining the vibration interference intensity threshold includes: under ideal working conditions with no significant vibration and synchronous motion, synchronously collecting vibration interference related feature data, calculating the vibration interference intensity index of each time window according to the weighting function in S2, and taking the upper quartile value of all time windows as the vibration interference intensity threshold.

10. A high-precision laser position detection dynamic compensation system, characterized in that, The compensation system is used to perform the compensation method as described in any one of claims 1-9, and the compensation system includes the following functional modules: Vibration interference data acquisition module: Set a fixed-length time window, and collect vibration interference related characteristic data of the device in each time window. The vibration interference related characteristic data includes vibration displacement amplitude, amplitude ratio and maximum peak-to-peak value of vibration signal. Interference intensity analysis module: preprocesses the collected vibration interference related feature data, removes DC components and high-frequency noise through a bandpass filter, performs normalization processing on the data in each time window, constructs a weighting function, and calculates and obtains the vibration interference intensity index; The laser spot and marker synchronous acquisition module: within a fixed time window, the three-dimensional coordinates of the laser spot on the target and the three-dimensional coordinates of the feature markers on the target are acquired at a fixed frequency using visual detection technology, forming a laser spot three-dimensional coordinate dataset and a feature marker three-dimensional coordinate dataset, respectively. Motion Deviation Index Calculation Module: Constructs a transformation function, which is used to calculate the deviation index within a fixed time window by inputting the three-dimensional coordinate dataset of the light spot and the three-dimensional coordinate dataset of the feature marker. Dynamic compensation decision and switching module: Set vibration interference intensity threshold and deviation threshold. When the deviation index is less than or equal to the deviation threshold, the current normal dynamic compensation mode is maintained. If the deviation index is greater than the deviation threshold, further comparison and judgment are performed: If the vibration interference intensity index is greater than the vibration interference intensity threshold, it indicates that the main cause of the high deviation index is vibration. At this time, switch to enhanced vibration suppression compensation mode and re-perform compensation decision; If the vibration interference intensity index is less than or equal to the vibration interference intensity threshold, it indicates that the main cause of the high deviation index is not vibration.

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