High-precision double-side thickness synchronous detection system for notebook computer shell

Abstract

The invention discloses a high-precision double-side thickness synchronous detection system for a notebook computer shell, and relates to the field of appearance detection, and the system comprises a positioning module which is used for receiving a to-be-detected notebook computer shell, adsorbing the surface of the shell through a plurality of groups of adjustable vacuum adsorption parts, and carrying out the automatic centering and posture calibration of the shell based on the feedback of a displacement sensor; the detection module integrates symmetrically-arranged detection units and is used for synchronously applying detection signals to preset detection points on the two sides of the positioned shell and collecting original detection data related to the thickness of the two sides; the adsorption pressure is dynamically adjusted along with the surface curvature, the posture is accurately calibrated in a linkage mode, it is ensured that the detection object is stably positioned, the posture deviation is extremely small, the detection signal counteracts the distance and medium attenuation influence through amplitude real-time compensation, the original data quality is optimized in cooperation with self-adaptive filtering denoising and accurate amplitude calibration, and the detection accuracy is improved. And temperature, humidity and other environmental factors and material characteristic correction are fused, so that the thickness calculation result is closer to reality.

Description

Technical Field

[0001] This invention relates to the field of appearance inspection technology, specifically to a high-precision dual-sided thickness synchronous detection system for laptop casings. Background Technology

[0002] The production testing of laptops covers hardware function verification, performance benchmarking, stability and compatibility verification, and appearance defect screening. By combining automated equipment with manual spot checks, the operating status of core components such as the motherboard, screen, and keyboard is verified item by item to ensure that the products meet quality standards and usage requirements.

[0003] Patent application number 202211068171.9 discloses a method for measuring the dimensions of a laptop casing. This application aims to solve the problem that "because the back panel of a laptop is relatively large, it needs to be measured in the same way as the customer to facilitate comparison of measurement data. If a point-to-point measurement method is used, this method has relatively poor dynamic repeatability and is greatly affected by the product's angular offset. If a large calibration board is used for overall calibration of the shooting position, this calibration is not affected by the angle, but it is easily affected by product changes and the addition of measurement items, and it cannot achieve dynamic updates of the camera's shooting position."

[0004] However, for laptops, most existing technologies use single-sided detection for thickness measurement, and there is room for improvement in both detection accuracy and efficiency.

[0005] To address this, we propose a high-precision dual-sided thickness synchronous detection system for laptop casings. Summary of the Invention

[0006] In view of the above-mentioned shortcomings of the existing technology, the present invention provides a high-precision dual-sided thickness synchronous detection system for laptop shells, which can effectively solve the problems of the existing technology.

[0007] To achieve the above objectives, the present invention is implemented through the following technical solutions; This invention discloses a high-precision dual-sided thickness synchronous detection system for laptop shells, comprising: a positioning module for receiving the laptop shell to be detected, adsorbing the shell surface through several sets of adjustable vacuum adsorption components, and automatically centering and calibrating the shell based on feedback from a displacement sensor; The detection module integrates symmetrically arranged detection units, which are used to synchronously apply detection signals to preset detection points on both sides of the positioned shell and collect raw detection data related to the thickness of both sides. The conversion module receives the raw signal output by the detection module, performs filtering, noise reduction, and amplitude calibration, and simultaneously converts the analog signal into a recognizable digital signal. The processing module is used to align the digital signals on both sides with timestamps, and then calculate the actual thickness value of each side of the shell to establish a reference data set of the thickness data on both sides. The output module is used to set the thickness standard parameters, compare with the control data set, and output the judgment result and specific value of whether the thickness of each test point is qualified. The control module is used to control the positioning module to complete the unloading or repositioning of the outer shell based on the output of the output module. During repositioning, the outer shell is subjected to secondary detection. Among them, the detection points are set on one side of the shell, and the corresponding reference detection points are set on the other side of the shell. The detection results of each set of detection points and reference detection points form a control data set, and several control data sets form a control data set. The positioning module is interconnected with the detection module via a wireless network. The detection module is interconnected with the conversion module and the processing module via a wireless network. The processing module is interconnected with the output module and the control module via a wireless network.

[0008] Furthermore, several sets of adjustable vacuum adsorption components in the positioning module are arranged in a distributed matrix. The adsorption pressure of the adsorption components is adjusted in real time based on the curvature of the outer shell surface. During adjustment, the adsorption pressure is positively correlated with the curvature of the outer shell surface. The displacement sensor is a laser displacement sensor. Its detection data is calibrated in real time through a preset calibration model. During the calibration process, the adsorption state signal of the adsorption component is collected simultaneously. When the adsorption pressure deviates from the preset range, the displacement sensor is triggered for secondary calibration, so that the attitude deviation after the shell is automatically centered does not exceed the preset attitude threshold.

[0009] Furthermore, the adjustable vacuum adsorption component in the positioning module is equipped with a pressure feedback sensor, and the adjustment range of the adsorption pressure is dynamically set based on the pressure bearing limit of the outer shell surface. ; In the formula: For real-time adsorption pressure; This is the maximum permissible adsorption pressure of the outer shell material; This represents the actual contact area between the current adsorption component and the outer shell. This refers to the rated contact area of ​​the adsorption element; The displacement sensor's detection data and adsorption pressure data are analyzed in real time: when the adsorption pressure fluctuation exceeds the preset fluctuation threshold, the detection process is paused and the shell posture is recalibrated.

[0010] Furthermore, the symmetrical detection unit in the detection module uses ultrasonic detection signals, and the amplitude of the detection signals is corrected in real time to offset the errors caused by detection distance and medium attenuation. The correction operation is the compensation operation for the amplitude of the detected signal: ; In the formula: The amplitude of the detected signal after compensation; The preset benchmark detection amplitude; Used as the baseline detection distance; This refers to the actual detection distance; The attenuation coefficient of the ultrasonic signal in the detection environment; The preset detection points are determined based on the feature point extraction results of the three-dimensional contour of the shell. The feature points include the inflection points of the two sides of the shell, the points around the openings, and the points corresponding to the stress concentration areas.

[0011] Furthermore, the conversion module employs an improved Kalman filter algorithm based on adaptive adjustment of signal features for noise reduction, suppressing noise by dynamically updating the process noise covariance and the observation noise covariance. ; In the formula: Let k be the process noise covariance at time k. The initial process noise covariance; This is the process noise adjustment factor; This represents the deviation between the filtered output value and the original signal value at time k-1. Let be the observation noise covariance at time k; The initial observation noise covariance; The reference frequency for detecting the signal; Let be the real-time frequency of the detected signal at time k; Amplitude calibration is as follows: ; In the formula: The amplitude of the calibrated analog signal; The original analog signal amplitude after filtering; This is the amplitude calibration coefficient; The difference between the original analog signal amplitude and the preset reference amplitude; When converting analog signals to digital signals, a 16-bit analog-to-digital converter chip is used. The conversion rate is synchronized with the signal acquisition rate of the detection module, and the conversion delay does not exceed the preset delay threshold.

[0012] Furthermore, the formula for calculating the amplitude calibration coefficient is as follows: ; In the formula: These are the initial calibration coefficients for the detection unit at the factory. The influence coefficient is the usage duration. The influence coefficient of the number of tests; This is a correction factor for the effect of temperature. This is a correction factor for the effect of humidity. The data includes the cumulative usage time of the detection unit, the cumulative number of tests conducted by the detection unit, the real-time temperature of the detection environment, and the real-time relative humidity of the detection environment. The preset baseline usage time, preset baseline test count, standard test temperature, and standard test relative humidity are set.

[0013] Furthermore, the alignment error of the timestamp alignment operation in the processing module does not exceed 5ns; Temperature correction is introduced when calculating the actual thickness value on one side: ; In the formula: This is the corrected actual thickness value on one side; The original thickness value is calculated based on digital signals; The coefficient of linear expansion of the outer casing material; To detect the real-time temperature of the environment; Standard testing temperature; When establishing a reference data set for bilateral thickness data, the spatial coordinates of each detection point and the reference detection point are recorded simultaneously.

[0014] Furthermore, the output module includes the pass / fail confidence level of the thickness at the corresponding detection point for each data set. ,in This indicates the standard deviation of a preset number of test data points. This indicates the number of samples tested at each testing point. Indicates the confidence level correction factor; When the confidence level is lower than the preset confidence threshold, the detection point is re-detected.

[0015] Furthermore, the repositioning trigger conditions of the control module are: the proportion of non-conforming detection points on one side exceeds the preset ratio, or the absolute value of the thickness deviation of a single detection point exceeds the preset deviation threshold, or the absolute value of the deviation of one or more sets of control data exceeds the preset deviation threshold. If the secondary test results still meet the triggering conditions, the casing is deemed unqualified; otherwise, the casing is deemed qualified.

[0016] Compared with the known prior art, the technical solution provided by this invention has the following beneficial effects: This invention improves detection efficiency through dual-sided synchronous detection. The adsorption pressure is dynamically adjusted according to the surface curvature and linked to precise attitude calibration, ensuring stable positioning of the detected object with minimal attitude deviation. The detection signal is compensated for in real time by amplitude compensation to offset the effects of distance and medium attenuation. Furthermore, it optimizes the quality of the original data by combining adaptive filtering for noise reduction and precise amplitude calibration. It incorporates environmental factors such as temperature and humidity, as well as material characteristics for correction, making the thickness calculation results closer to reality. This dual-sided data comparison and pass / fail confidence assessment ensure accurate judgment. The repositioning secondary detection mechanism effectively reduces the risk of misjudgment and is adaptable to different surface morphologies, materials, and complex detection environments, effectively improving detection accuracy and stability. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0018] Figure 1 This is a schematic diagram of a high-precision dual-sided thickness synchronous detection system for a laptop casing. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0020] The present invention will be further described below with reference to embodiments.

[0021] Example: This embodiment provides a high-precision dual-sided thickness synchronous detection system for a laptop casing, such as... Figure 1 As shown, it includes: The positioning module is used to receive the laptop shell to be tested, adsorb the shell surface through several sets of adjustable vacuum adsorption components, and automatically center and calibrate the shell based on the feedback of the displacement sensor. In the positioning module, several sets of adjustable vacuum adsorption elements are arranged in a distributed matrix. The adsorption pressure of the adsorption elements is adjusted in real time based on the curvature of the outer shell surface. During adjustment, the adsorption pressure is positively correlated with the curvature of the outer shell surface. The displacement sensor is a laser displacement sensor. Its detection data is calibrated in real time through a preset calibration model. During the calibration process, the adsorption state signal of the adsorption component is collected simultaneously. When the adsorption pressure deviates from the preset range, the displacement sensor is triggered for secondary calibration so that the attitude deviation after the shell is automatically centered does not exceed the preset attitude threshold. The adjustable vacuum adsorption component in the positioning module is equipped with a pressure feedback sensor, and the adjustment range of the adsorption pressure is dynamically set based on the pressure bearing limit of the outer shell surface. ; In the formula: For real-time adsorption pressure; This is the maximum permissible adsorption pressure of the outer shell material; This represents the actual contact area between the current adsorption component and the outer shell. This refers to the rated contact area of ​​the adsorption element; The above formula determines the real-time adsorption pressure based on the maximum allowable adsorption pressure that the shell material can withstand, and the ratio of the actual contact area between the current adsorption component and the shell to the rated contact area of ​​the adsorption component. It can dynamically adapt to different curvatures of the shell surface, ensuring that the adsorption pressure is positively correlated with the curvature of the shell surface, while never exceeding the pressure limit of the shell. This avoids damage to the shell caused by excessive adsorption pressure, and also prevents unstable adsorption caused by insufficient pressure, which affects the positioning accuracy. This keeps the shell stable and undamaged during the positioning process. The displacement sensor's detection data and adsorption pressure data are analyzed in real time: when the adsorption pressure fluctuation exceeds the preset fluctuation threshold, the detection process is paused and the shell posture is recalibrated. The detection module integrates symmetrically arranged detection units, which are used to synchronously apply detection signals to preset detection points on both sides of the positioned shell and collect raw detection data related to the thickness of both sides. The symmetrical detection unit in the detection module uses ultrasonic detection signals, and the amplitude of the detection signals is corrected in real time to compensate for the errors caused by detection distance and medium attenuation. The correction operation is the compensation operation for the amplitude of the detected signal: ; In the formula: The amplitude of the detected signal after compensation; The preset benchmark detection amplitude; Used as the baseline detection distance; This refers to the actual detection distance; The attenuation coefficient of the ultrasonic signal in the detection environment; Among them, the preset detection points are determined based on the feature point extraction results of the three-dimensional contour of the shell. The feature points include the inflection points of the two sides of the shell, the points around the openings, and the points corresponding to the stress concentration areas. The above formula uses a preset benchmark detection amplitude and benchmark detection distance as a reference, combined with the detection distance in the actual detection process and the attenuation coefficient of the ultrasonic signal in the current detection environment, to specifically compensate the amplitude of the detection signal. This not only corrects the signal strength deviation caused by the inconsistency between the actual detection distance and the benchmark distance, but also fully offsets the attenuation effect of the environmental medium on the ultrasonic signal. The attenuation coefficient is adjusted according to the changes in temperature, humidity and impurity gas concentration in the detection environment to ensure that the compensated detection signal amplitude can accurately reflect the real situation related to the shell thickness, providing an effective raw signal for subsequent data processing. The preset value range is 0.05~0.3. Its value increases with the increase of ambient temperature, humidity or impurity gas concentration, and decreases with the decrease of ambient temperature, humidity or impurity gas concentration. The symmetrical detection unit of the detection module is equipped with an attitude adjustment mechanism. Based on the deviation of the thickness data on both sides output by the processing module, the angle between the detection unit and the shell surface is adjusted in real time so that the detection signal is always perpendicular to the tangent plane of the detection point on the shell. The angle adjustment amount is determined according to the angle deviation between the surface normal vector of the detection point and the initial axis of the detection unit. The conversion module receives the raw signal output by the detection module, performs filtering, noise reduction, and amplitude calibration, and simultaneously converts the analog signal into a recognizable digital signal. The conversion module employs an improved Kalman filter algorithm based on adaptive adjustment of signal characteristics for noise reduction. Noise suppression is achieved by dynamically updating the process noise covariance and the observation noise covariance. ; In the formula: Let k be the process noise covariance at time k. The initial process noise covariance; This is the process noise adjustment factor; This represents the deviation between the filtered output value and the original signal value at time k-1. Let be the observation noise covariance at time k; The initial observation noise covariance; The reference frequency for detecting the signal; Let be the real-time frequency of the detected signal at time k; The above formula addresses the dynamic changes in noise during the filtering and denoising process. It adjusts the process noise covariance based on the deviation between the filtered output value and the original signal value at the previous moment. The larger the deviation, the more significant the adjustment. At the same time, it adjusts the observation noise covariance by combining the ratio of the real-time frequency of the detection signal to the reference frequency. This allows the noise suppression process to adapt to the fluctuation state and frequency changes of the signal, effectively filtering interference noise under different working conditions. It avoids the problem of poor filtering effect caused by fixed covariance settings, making the filtered signal more closely match the characteristics of the real detection data. Amplitude calibration is as follows: ; In the formula: The amplitude of the calibrated analog signal; The original analog signal amplitude after filtering; This is the amplitude calibration coefficient; The difference between the original analog signal amplitude and the preset reference amplitude; The above formula is based on the original analog signal amplitude after filtering. It introduces an amplitude calibration coefficient and the difference between the original analog signal amplitude and the preset reference amplitude to calibrate and adjust the signal amplitude. The magnitude of the calibration coefficient will change dynamically according to the actual situation. It can accurately correct the amplitude deviation caused by factors such as equipment status and environmental fluctuations during the detection process, so that the calibrated analog signal amplitude is more in line with the actual detection requirements. It provides an accurate signal basis for the subsequent conversion of analog signals to digital signals and reduces the error transmission during the signal conversion process. When converting analog signals to digital signals, a 16-bit analog-to-digital converter chip is used. The conversion rate is synchronized with the signal acquisition rate of the detection module, and the conversion delay does not exceed the preset delay threshold. in, >0, the value is larger when the increase of the process noise covariance at time k is more significant as the increase of the deviation between the filtered output value and the original signal value at time k-1 is more significant, and the value is smaller when the increase is more gradual; >0 indicates that the value is larger when the cumulative usage time of the detection unit is closer to or exceeds the preset benchmark usage time, the cumulative number of detections is closer to or exceeds the preset benchmark number of detections, and the absolute value of the deviation between the real-time temperature and humidity of the detection environment and the standard detection value is larger and the fluctuation / change is more drastic; conversely, the value is smaller. The formula for calculating the amplitude calibration coefficient is: ; In the formula: These are the initial calibration coefficients for the detection unit at the factory. The influence coefficient is the usage duration. The influence coefficient of the number of tests; This is a correction factor for the effect of temperature. This is a correction factor for the effect of humidity. The data includes the cumulative usage time of the detection unit, the cumulative number of tests conducted by the detection unit, the real-time temperature of the detection environment, and the real-time relative humidity of the detection environment. The preset baseline usage time, preset baseline test count, standard test temperature, and standard test relative humidity are set. The above formula takes the initial calibration coefficient of the detection unit at the factory as the basis. Based on the cumulative usage time of the detection unit, the cumulative number of tests, and the deviation of the real-time temperature and relative humidity of the detection environment from the standard value, different influence coefficients are used to quantify the effect of each factor on the calibration effect. The longer the usage time and the more tests, the calibration coefficient is adjusted accordingly to adapt to the aging of the equipment and the fatigue of the components. The greater the temperature and humidity deviation and the more violent the fluctuation, the more the influence of the environment is offset by the coefficient adjustment, so that the amplitude calibration coefficient can dynamically adapt to the changes in equipment status and environmental conditions, ensuring that each calibration is effective. in, The value range is preset to [0.001, 0.01]. The value is larger when the cumulative usage time of the detection unit is closer to or exceeds the preset benchmark usage time and the signs of aging of the core components are more obvious. The value is smaller when the cumulative usage time is much lower than the preset benchmark usage time and the performance status of the core components is closer to the factory calibration value. The value range is preset to [0.0005, 0.005]. The value is larger when the cumulative number of detections of the detection unit is closer to or exceeds the preset benchmark number of detections and the fatigue degree of the signal transmitting element is higher. The value is smaller when the cumulative number of detections is much lower than the preset benchmark number of detections and the fatigue loss of the signal transmitting element is negligible. The preset value range is [0.02, 0.1]. The larger the absolute value of the deviation between the real-time temperature of the detection environment and the standard detection temperature, and the more violent the temperature fluctuation, the larger the value. The smaller the absolute value of the temperature deviation and the more stable the detection environment temperature, the smaller the value. The preset value range is [0.01, 0.08]. The larger the absolute value of the deviation between the real-time relative humidity of the detection environment and the standard detection relative humidity, and the more frequent the humidity changes, the larger the value is. The smaller the absolute value of the humidity deviation and the more stable the humidity of the detection environment, the smaller the value is. The processing module is used to align the digital signals on both sides with timestamps, and then calculate the actual thickness value of each side of the shell to establish a reference data set of the thickness data on both sides. The alignment error of the timestamp alignment operation in the processing module does not exceed 5ns; Temperature correction is introduced when calculating the actual thickness value on one side: ; In the formula: This is the corrected actual thickness value on one side; The original thickness value is calculated based on digital signals; The coefficient of linear expansion of the outer casing material; To detect the real-time temperature of the environment; Standard testing temperature; The above formula is based on the original thickness value calculated from digital signals. It is combined with the linear expansion coefficient of the shell material itself and the difference between the real-time temperature of the detection environment and the standard detection temperature to correct the thickness value. The linear expansion coefficient will be adjusted according to the composition difference of the shell material. The higher the content of alloy elements and the tighter the molecular bonding, the smaller the coefficient. The higher the proportion of non-metallic components and the larger the molecular gap, the larger the coefficient. It fully considers the influence of temperature change on the expansion or contraction of the shell material, effectively offsetting the thickness measurement error caused by temperature factors, and making the calculated actual thickness value on one side more consistent with the true thickness of the shell. When establishing a reference data set for bilateral thickness data, the spatial coordinates of each detection point and the reference detection point are recorded simultaneously. in, The preset value range is 1.0 × 10. Up to 2.5×10 The higher the alloy element content and the tighter the molecular bonding of the outer shell material, The smaller the value, the higher the proportion of non-metallic components in the material and the larger the intermolecular gaps. The larger the value; The output module is used to set the thickness standard parameters, compare with the control data set, and output the judgment result and specific value of whether the thickness of each test point is qualified. The output module includes the pass / fail confidence level of the thickness at the corresponding detection point for each data set. ,in This indicates the standard deviation of a preset number of test data points. This indicates the number of samples tested at each testing point. Indicates the confidence level correction factor; The above formula quantifies the pass / fail confidence of the test results by pre-setting the standard deviation of several test data, the number of test samples, and the confidence correction factor for the test points. The standard deviation reflects the dispersion of the test data, the number of samples reflects the sufficiency of the test, and the correction factor is adjusted according to the measurement repeatability of the test points. The worse the measurement repeatability, the larger the correction factor value, and vice versa. This objectively evaluates the reliability of the thickness test results of each test point. When the confidence level is lower than the preset confidence threshold, the test point can be retested to avoid misjudgment due to the randomness of a single test data and improve the accuracy and rigor of the pass / fail judgment of the entire test system. When the confidence level is lower than the preset confidence threshold, the detection point is re-detected. in, ∈ (0.8, 1.2), when the measurement repeatability of the detection point is worse... The larger the value, the lower the value. The smaller the value; The control module is used to control the positioning module to complete the unloading or repositioning of the outer shell based on the output of the output module. During repositioning, the outer shell is subjected to secondary detection. The repositioning trigger conditions of the control module are: the proportion of non-conforming detection points on one side exceeds the preset ratio, or the absolute value of the thickness deviation of a single detection point exceeds the preset deviation threshold, or the absolute value of the deviation of one or more sets of control data exceeds the preset deviation threshold. If the secondary test result still meets the triggering conditions, the casing is deemed unqualified; otherwise, the casing is deemed qualified. Among them, the detection points are set on one side of the shell, and the corresponding reference detection points are set on the other side of the shell. The detection results of each set of detection points and reference detection points form a control data set, and several control data sets form a control data set. The positioning module is interconnected with the detection module via a wireless network. The detection module is interconnected with the conversion module and the processing module via a wireless network. The processing module is interconnected with the output module and the control module via a wireless network.

[0022] In this embodiment, the positioning module receives the laptop shell to be tested, adsorbs the shell surface using several sets of adjustable vacuum adsorption components, and automatically centers and calibrates the shell based on feedback from a displacement sensor. Simultaneously, the detection module applies detection signals to preset detection points on both sides of the positioned shell, collecting raw detection data related to the thickness on both sides. The conversion module receives the raw signal output from the detection module, performs filtering, noise reduction, and amplitude calibration, and simultaneously converts the analog signal into a recognizable digital signal. The processing module then timestamps the digital signals on both sides and calculates the actual thickness value on each side of the shell to establish a reference data set for the thickness data on both sides. The output module further sets thickness standard parameters, compares the data set with the reference data set, and outputs the judgment result and specific value of whether the thickness at each detection point is qualified. Finally, the control module, based on the output result of the output module, controls the positioning module to complete the shell unloading or repositioning. During repositioning, the shell undergoes a secondary inspection.

[0023] The system described in the above embodiments can accurately and synchronously detect the thickness of both sides of a laptop casing, automatically adapt to changes in casing shape and environment, effectively counteract various interference factors, ensure accurate and reliable detection data, reduce the false judgment rate through a secondary verification mechanism, improve detection efficiency and product quality control, adapt to the detection needs of casings with different materials and structures, and provide stable and efficient thickness detection support for the production process.

[0024] Refer to the system in the above embodiments, and a application example of the system is shown: XX Electronics Factory uses this system to conduct inspections on the laptop computer casings made of aluminum alloy. First, the positioning module adsorbs the surface of the casing through adjustable vacuum adsorbing components arranged in a distributed matrix, and adjusts the adsorption pressure in real time according to the curvature of different areas of the casing. Finally, the adsorption pressure adapts to the maximum allowable bearing pressure standard of this material. At the same time, the laser displacement sensor calibrates the posture of the casing in real time, and controls the posture deviation within the preset threshold of 0.02 mm, successfully completing the automatic centering and posture calibration of the casing.

[0025] Next, the symmetric ultrasonic detection unit of the detection module is started synchronously. Detection signals are applied to the preset detection points at the bilateral edge inflection points, around the openings and in the stress concentration areas of the casing. The signal amplitude is corrected in combination with the actual detection distance and environmental attenuation conditions to ensure the accuracy of the detection signals. At the same time, the included angle of the detection unit is adjusted through the posture adjustment mechanism so that the detection signals are always perpendicular to the tangent plane of the detection points.

[0026] The conversion module uses an improved Kalman filtering algorithm to remove the noise of the original signal, and then completes the amplitude calibration according to the usage duration, detection times and environmental temperature and humidity of the detection unit. The calibrated analog signal is converted into a digital signal by a 16-bit analog-to-digital conversion chip, and the conversion delay does not exceed the preset standard.

[0027] The processing module aligns the bilateral digital signals in terms of time stamps, controls the alignment error within 5 ns, and performs thickness correction in combination with the real-time temperature of 25 °C in the detection environment to obtain the actual thickness values of each single side, and records the spatial coordinates of the corresponding detection points to form a comparison data set.

[0028] The output module sets the standard thickness of the casing to 1.2 mm, with an allowable deviation of ±0.02 mm. After comparing the comparison data set, the thickness of all detection points is between 1.18 mm and 1.22 mm, and the qualified confidence level of each detection point reaches above 0.98, which is higher than the preset confidence threshold of 0.9. It is determined that the thickness detection of the casing is qualified. The control module controls the positioning module to complete the unloading of the casing according to the qualified result, efficiently achieving the accurate detection goal.

[0029] In summary, the system in the above embodiments improves detection efficiency through dual-sided synchronous detection, dynamically adjusts the adsorption pressure according to the surface curvature and links it with precise attitude calibration to ensure stable positioning of the detected object and minimal attitude deviation. The detection signal compensates for the influence of distance and medium attenuation through real-time amplitude compensation, and optimizes the quality of the original data by combining adaptive filtering for noise reduction and precise amplitude calibration. It also incorporates environmental factors such as temperature and humidity and material characteristics for correction, making the thickness calculation results closer to reality. This dual-sided data comparison and qualified confidence assessment ensure accurate judgment, and the repositioning secondary detection mechanism effectively reduces the risk of misjudgment. It is adaptable to different surface morphologies, materials and complex detection environments, and effectively improves detection accuracy and stability.

[0030] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions will not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A high-precision dual-sided thickness synchronous detection system for laptop casing, characterized in that, include: The positioning module is used to receive the laptop shell to be tested, adsorb the shell surface through several sets of adjustable vacuum adsorption components, and automatically center and calibrate the shell based on the feedback of the displacement sensor. The detection module integrates symmetrically arranged detection units, which are used to synchronously apply detection signals to preset detection points on both sides of the positioned shell and collect raw detection data related to the thickness of both sides. The conversion module receives the raw signal output by the detection module, performs filtering, noise reduction, and amplitude calibration, and simultaneously converts the analog signal into a recognizable digital signal. The processing module is used to align the digital signals on both sides with timestamps, and then calculate the actual thickness value of each side of the shell to establish a reference data set of the thickness data on both sides. The output module is used to set the thickness standard parameters, compare with the control data set, and output the judgment result and specific value of whether the thickness of each test point is qualified. The control module is used to control the positioning module to complete the unloading or repositioning of the outer shell based on the output of the output module. During repositioning, the outer shell is subjected to secondary detection. The detection points are set on one side of the shell, and there are corresponding reference detection points on the other side of the shell. The detection results of each set of detection points and reference detection points form a control data set, and several control data sets form a control data set.

2. The high-precision dual-sided thickness synchronous detection system for a laptop casing according to claim 1, characterized in that, In the positioning module, several sets of adjustable vacuum adsorption elements are arranged in a distributed matrix. The adsorption pressure of the adsorption elements is adjusted in real time based on the curvature of the outer shell surface. During adjustment, the adsorption pressure is positively correlated with the curvature of the outer shell surface. The displacement sensor is a laser displacement sensor. Its detection data is calibrated in real time through a preset calibration model. During the calibration process, the adsorption state signal of the adsorption component is collected synchronously. When the adsorption pressure deviates from the preset range, the displacement sensor is triggered for secondary calibration, so that the attitude deviation after the shell is automatically centered does not exceed the preset attitude threshold.

3. The high-precision dual-sided thickness synchronous detection system for a laptop casing according to claim 2, characterized in that, The adjustable vacuum adsorption component in the positioning module is equipped with a pressure feedback sensor, and the adjustment range of the adsorption pressure is dynamically set based on the pressure bearing limit of the outer shell surface. ； In the formula: For real-time adsorption pressure; This is the maximum permissible adsorption pressure of the outer shell material; This represents the actual contact area between the current adsorption component and the outer shell. This refers to the rated contact area of ​​the adsorption element; The detection data from the displacement sensor and the adsorption pressure data are analyzed in real time: when the adsorption pressure fluctuation exceeds the preset fluctuation threshold, the detection process is paused and the shell posture is recalibrated.

4. The high-precision dual-sided thickness synchronous detection system for a laptop casing according to claim 1, characterized in that, The symmetrical detection unit in the detection module uses ultrasonic detection signals, and the amplitude of the detection signals is corrected in real time to offset the errors caused by detection distance and medium attenuation. The correction operation is a compensation operation for the amplitude of the detected signal: ； In the formula: The amplitude of the detected signal after compensation; The preset benchmark detection amplitude; Used as the baseline detection distance; This refers to the actual detection distance; The attenuation coefficient of the ultrasonic signal in the detection environment; The preset detection points are determined based on the feature point extraction results of the three-dimensional contour of the shell. The feature points include the inflection points of the two sides of the shell, the points around the openings, and the points corresponding to the stress concentration areas.

5. A high-precision dual-sided thickness synchronous detection system for a laptop casing according to claim 1, characterized in that, The conversion module employs an improved Kalman filter algorithm based on adaptive adjustment of signal characteristics for noise reduction. Noise suppression is achieved by dynamically updating the process noise covariance and the observation noise covariance. ； In the formula: Let k be the process noise covariance at time k. The initial process noise covariance; This is the process noise adjustment factor; This represents the deviation between the filtered output value and the original signal value at time k-1. Let be the observation noise covariance at time k; The initial observation noise covariance; The reference frequency for detecting the signal; Let be the real-time frequency of the detected signal at time k; The amplitude calibration is as follows: ； In the formula: The amplitude of the calibrated analog signal; The original analog signal amplitude after filtering; This is the amplitude calibration coefficient; The difference between the original analog signal amplitude and the preset reference amplitude; When converting analog signals to digital signals, a 16-bit analog-to-digital converter chip is used. The conversion rate is synchronized with the signal acquisition rate of the detection module, and the conversion delay does not exceed the preset delay threshold.

6. A high-precision dual-sided thickness synchronous detection system for a laptop casing according to claim 5, characterized in that, The formula for calculating the amplitude calibration coefficient is as follows: ； In the formula: These are the initial calibration coefficients for the detection unit at the factory. The influence coefficient is the usage duration. The influence coefficient of the number of tests; This is a correction factor for the effect of temperature. This is a correction factor for the effect of humidity. The data includes the cumulative usage time of the detection unit, the cumulative number of tests conducted by the detection unit, the real-time temperature of the detection environment, and the real-time relative humidity of the detection environment. The preset baseline usage time, preset baseline test count, standard test temperature, and standard test relative humidity are set.

7. The high-precision dual-sided thickness synchronous detection system for a laptop casing according to claim 1, characterized in that, The alignment error of the timestamp alignment operation in the processing module does not exceed 5ns; Temperature correction is incorporated when calculating the actual thickness value on one side: ； In the formula: This is the corrected actual thickness value on one side; The original thickness value is calculated based on digital signals; The coefficient of linear expansion of the outer casing material; To detect the real-time temperature of the environment; Standard testing temperature; When establishing the reference data set for the bilateral thickness data, the spatial coordinates of each detection point and the reference detection point are recorded simultaneously.

8. A high-precision dual-sided thickness synchronous detection system for a laptop casing according to claim 1, characterized in that, The output module includes the pass / fail confidence level of the thickness of the corresponding detection point in each data set. ,in This indicates the standard deviation of a preset number of test data points. This indicates the number of samples tested at each testing point. Indicates the confidence level correction factor; When the confidence level is lower than the preset confidence threshold, the detection point is re-detected.

9. A high-precision dual-sided thickness synchronous detection system for a laptop casing according to claim 1, characterized in that, The repositioning trigger conditions of the control module are: the proportion of non-conforming detection points on one side exceeds the preset proportion, or the absolute value of the thickness deviation of a single detection point exceeds the preset deviation threshold, or the absolute value of the deviation of one or more sets of control data exceeds the preset deviation threshold. If the secondary test results still meet the triggering conditions, the casing is deemed unqualified; otherwise, the casing is deemed qualified.

10. A high-precision dual-sided thickness synchronous detection system for a laptop casing according to claim 1, characterized in that, The positioning module is interconnected with the detection module via a wireless network. The detection module is interconnected with the conversion module and the processing module via a wireless network. The processing module is interconnected with the output module and the control module via a wireless network.

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