A peel test method and system for waxless adsorbent pad adhesion

Abstract

The application relates to the technical field of adhesion performance testing, in particular to a wax-free adsorption pad adhesion force peeling test method and system, which comprises the following steps: calculating a differential value based on continuous tension data; when the differential value changes from positive to negative and the absolute value of the differential value exceeds a preset tearing threshold value, locking the tension data of a preset first time length before the current time in the cache and merging the tension data into a mutation frame; extracting the time stamp of each first wave trough in the continuous sampling data and calculating the time difference variance; generating an inverse sine envelope to obtain a pure curve; generating a correction slope and a reconstruction constant; extracting the falling slope from the wave peak to the second wave trough and the climbing time from the second wave trough to the next peak from the pure curve; and determining the failure mode according to the comparison result of the falling slope and the correction slope and the climbing time and the reconstruction constant. The application can solve the defects of wave peak defects and signal aliasing and realize failure mode determination.

Description

Technical Field

[0001] This application relates to the technical field of adhesion performance testing, and in particular to a peel test method and system for the adhesion of a wax-free adsorption pad. Background Technology

[0002] When evaluating the adhesion performance of wax-free adhesive pads with porous network structures, a peel tester is typically used to perform a constant-speed 180-degree tensile test. The tester body relies on a servo motor to drive the transmission screw, which in turn drives the fixture to apply a continuous peel load to the material. Force data is continuously collected by mechanical sensors to reflect the fracture evolution process at the interface. Porous network structure materials contain a large number of micropores, which will undergo typical stick-slip fracture when subjected to stress and tearing. This is manifested in the stress curve as an instantaneous high-frequency extreme value change and a cliff-like drop. At the same time, the mechanical operation of the servo transmission system and the screw will continuously superimpose low-frequency periodic vibrations throughout the physical test path, resulting in a multi-frequency mixed state of the original mechanical signal.

[0003] Chinese invention patent application CN120721628A discloses an automated method and system for testing the peel force of adhesive tape. This technical solution sets a constant stress sampling interval to obtain a three-dimensional stress vector sequence, marks positions where the angle between adjacent points exceeds a set threshold as stress direction reversal points, and establishes a density index system by combining energy consumption difference and reversal frequency. When processing mechanical data, this solution extracts the tensile measurement sequence of potential force value offset segments and calculates the first-order difference between adjacent data points. For data points where the first-order difference exceeds the rate of change threshold, the system identifies them as abnormal data and performs linear interpolation fitting of adjacent points for numerical replacement. Finally, based on the reconstructed tensile amplitude and displacement increment, the energy distribution is calculated to classify the interface fracture stage.

[0004] When the aforementioned technical solution is applied to porous material peeling conditions, its underlying processing logic, which uniformly defines points of drastic change in local first-order difference as abnormal deviations and forcibly performs interpolation replacement, directly flattens out the high-frequency physical peak as an interference signal when facing the actual extreme stress value generated at the moment of microporous stick-slip fracture. This forced linear fitting at the numerical post-processing level inevitably flattens out the stress characteristics in the early stage of micro-tears, distorts the original tensile drop slope and secondary climbing pattern, causing the reconstructed mechanical data to lose its causal relationship with the actual physical failure action. In addition, the mechanism relying on constant interval sampling and numerical smoothing cannot separate the high-frequency signal generated by the sudden fracture of the material from the low-frequency mechanical noise superimposed by the transmission mechanism at the physical acquisition end. This aliasing in the frequency domain and the incompleteness of the characteristic peaks make it impossible for the system to accurately distinguish from a purely mechanical dimension whether the stress failure is due to the detachment of the adhesive layer interface or the cohesive tearing of the material itself. Summary of the Invention

[0005] To address the defects of incomplete wave peaks and signal aliasing, and to achieve failure mode determination, this application provides a peel test method and system for the adhesion of wax-free adsorption pads.

[0006] In a first aspect, this application provides a peel test method for the adhesion of a wax-free absorbent pad, which adopts the following technical solution: A peel test method for the adhesion of a wax-free absorbent pad includes: In a peel test performed on the test object, tensile data at a first frequency is acquired and continuously stored in a cache. A differential value is calculated based on the continuous tensile data, and the tensile data is downsampled to output sampled data at a second frequency, wherein the first frequency is greater than the second frequency. When the differential value changes from positive to negative and the absolute value of the differential value exceeds the preset tearing threshold, the tension data of the first preset duration before the current time in the cache is locked, and the locked tension data and the added tension data of the second preset duration are sequentially merged into a mutation frame; Extract the timestamps of each first trough in the continuous sampling data and calculate the time difference variance. When the time difference variance is less than the preset period tolerance, calculate the fundamental frequency of the continuous sampling data through a preset sliding window. Generate an inverted sinusoidal envelope, update the phase zero of the inverted sinusoidal envelope for each of the first valleys based on the fundamental frequency, and time-domain superimpose the inverted sinusoidal envelope after updating the phase zero with the abrupt frame to obtain a clean curve; The preset slope threshold is corrected based on the thickness of the test object to generate a corrected slope, and the preset rebound time is mapped based on the hardness of the test object to generate a reconstruction constant. Extract the drop slope from the peak to the second trough and the climbing time from the second trough to the next peak from the pure curve. The failure mode is determined based on the comparison results of the drop slope and the correction slope, the ramp time and the reconstruction constant.

[0007] Optionally, the steps of acquiring tensile force data at a first frequency and continuously storing it in a cache during a peel test on the test object, calculating the differential value based on the continuous tensile force data, and downsampling the tensile force data to output sampled data at a second frequency include: Set the cache as a circular cache; The tensile data is generated by sampling at the first frequency, and the tensile data is then overwritten into the circular buffer. The continuous tensile data in the circular buffer is read in real time, and a differential operation is performed in combination with a preset step size to obtain the differential value, thereby constructing a trigger baseline; The downsampling is performed synchronously with the rolling over to output the sampled data to a separate register.

[0008] Optionally, the step of locking the tension data in the cache for a preset first duration prior to the current time, and sequentially merging the locked tension data with the appended tension data for a preset second duration into a mutation frame, includes: The trigger baseline is monitored, and a hardware interrupt is triggered when it is determined that the differential value changes from positive to negative and the absolute value of the differential value exceeds the preset tearing threshold. In response to the hardware interrupt, the rolling over is stopped to lock the tension data of the preset first duration before the current time in the circular buffer; The tensile data of the preset second duration is collected, and the locked tensile data and the tensile data of the preset second duration are sequentially spliced ​​to generate the mutation frame, which is then exported to the preset frame register.

[0009] Optionally, before triggering the hardware interrupt, the following steps are included: Obtain the current displacement of the peel test; When the current displacement is less than the preset pull-up tolerance, the monitoring of the trigger baseline is locked to block the hardware interrupt.

[0010] Optional, also includes: Obtain the absolute tension corresponding to the current displacement; When the absolute tensile force falls into the preset void dead zone, and the continuous displacement maintained in the preset void dead zone exceeds the preset displacement threshold, it is determined that there is an air bubble in the segment corresponding to the continuous displacement. The tensile data of the segment corresponding to the continuous displacement is marked with a preset invalid label, and the tensile data is removed based on the physical address mapped by the preset invalid label when calculating the average peel force.

[0011] Optionally, the step of generating an anti-phase sinusoidal envelope and updating the phase zeros of the anti-phase sinusoidal envelope for each of the first valleys based on the fundamental frequency includes: The inverted sinusoidal envelope is generated based on the fundamental frequency; Obtain the timestamps of each of the first troughs; The overall phase of the inverted sine envelope at each of the timestamps is adjusted to the phase corresponding to the preset extreme value, so as to update the phase zero point.

[0012] Optionally, the step of time-domain superimposing the inverted sinusoidal envelope after updating the phase zero with the abrupt frame to obtain a pure curve includes: The inverted sinusoidal envelope after updating the phase zero point is synchronized in the time domain with the abrupt frame. The synchronized inverted sinusoidal envelope and the abrupt frame are summed point by point to generate a superimposed sequence; Based on the superimposed sequence, the periodic components within the mutated frame are filtered out, and the retained data points are output as the pure curve.

[0013] Optionally, the steps of correcting a preset slope threshold based on the thickness of the object under test to generate a corrected slope, and mapping a preset rebound time based on the hardness of the object under test to generate a reconstruction constant, include: The preset slope threshold is lowered based on the thickness of the object being measured to generate the corrected slope, and the thickness of the object being measured is positively correlated with the downward adjustment. The reconstruction constant is generated by mapping the preset rebound time to the hardness of the test object, and the hardness of the test object is negatively correlated with the reconstruction constant.

[0014] Optionally, the step of determining the failure mode based on the comparison results of the drop slope and the corrected slope, the ramp time and the reconstruction constant includes: When the drop slope is greater than the correction slope and the climbing time is less than the reconstruction constant, it is determined that interface detachment has occurred. When the drop slope is less than or equal to the corrected slope, the ramp time is greater than the reconstruction constant, and multiple sawtooth peaks are identified within the interval of the ramp time corresponding to the pure curve, cohesive tearing is determined to have occurred.

[0015] Secondly, the peel test system for the adhesion of a wax-free absorbent pad provided in this application adopts the following technical solution: A peel test system for the adhesion of a wax-free absorbent pad includes: The data acquisition module is used to acquire tensile data at a first frequency and store it in a buffer during a peel test performed on the test object, calculate the differential value based on the continuous tensile data, and downsample the tensile data to output sampled data at a second frequency, wherein the first frequency is greater than the second frequency. The mutation frame generation module is used to lock the tension data of a preset first duration before the current time in the cache when the differential value changes from positive to negative and the absolute value of the differential value exceeds a preset tearing threshold, and to sequentially merge the locked tension data with the added tension data of a preset second duration into a mutation frame; The signal decoupling module is used to extract the timestamps of each first valley in the continuous sampling data and calculate the time difference variance. When the time difference variance is less than a preset period tolerance, the fundamental frequency of the continuous sampling data is calculated through a preset sliding window. An inverted sinusoidal envelope is generated, and the phase zero of the inverted sinusoidal envelope is updated for each first valley based on the fundamental frequency. The inverted sinusoidal envelope after updating the phase zero is then superimposed with the abrupt frame in the time domain to obtain a clean curve. The failure determination module is used to correct a preset slope threshold based on the thickness of the test object to generate a corrected slope, and to map a preset rebound time based on the hardness of the test object to generate a reconstruction constant; to extract the drop slope from the peak to the second trough and the climbing time from the second trough to the second peak from the pure curve; and to determine the failure mode based on the comparison results of the drop slope and the corrected slope, and the climbing time and the reconstruction constant.

[0016] In summary, this application includes the following beneficial technical effects: 1. By collecting tensile data at the first frequency and rolling the buffer during the peel test, the differential value is calculated based on the continuous data to trigger the process. When the differential value jumps between positive and negative and the absolute value exceeds the tearing threshold, the buffer data containing the leading edge of the wave crest is locked to generate a mutation frame. This avoids the wave crest being overwritten by the ring buffer or smoothed out by subsequent values. Combined with the low-frequency periodic components extracted from the sampled data to construct an inverse sinusoidal envelope and superimpose it with the mutation frame in the time domain to filter out mechanical noise, the stress curve can retain the complete wave crest, drop slope and climbing shape, thus providing a data basis that conforms to the physical fracture time sequence for the separation interface detachment and cohesive tearing.

[0017] 2. By setting the cache as a circular cache and simultaneously downsampling the sampled data to an independent register while overwriting with the first frequency sampling, and stopping the overwriting and latching the first duration of data before the trigger with a hardware interrupt, the peak timing offset caused by interrupt response delay or software processing lag is eliminated, so that the high-frequency break time and the locked data segment are precisely aligned on the physical time axis, improving the real-time performance of trigger positioning and the integrity of locked data.

[0018] 3. By acquiring the current displacement and setting the early trigger of the pull-up tolerance lockout, false drops caused by edge defects on the end face are shielded. Based on the relationship between displacement and absolute tensile force, void dead zones and bubble segments are identified to remove invalid data in the average peel force calculation. At the same time, the slope threshold and rebound time are corrected based on the thickness and hardness of the tested material, so that the input parameters for failure judgment are adapted to the differences in mechanical properties of different batches of materials, and the interference of edge state and process defects on the judgment results is suppressed. Attached Figure Description

[0019] Figure 1A flowchart illustrating a peel test method for the adhesion of a wax-free adsorption pad, as provided in this application embodiment; Figure 2 Data charts showing the interface exiting failure modes provided in embodiments of this application; Figure 3 Data charts for cohesive tearing failure modes provided in embodiments of this application. Detailed Implementation

[0020] The following combination Figures 1-3 This application will be described in further detail.

[0021] This application discloses a peel test method for the adhesion of a wax-free adsorption pad, applied to the adhesion performance testing of a porous network structure wax-free adsorption pad under a 180° constant speed peel condition. The testing machine body includes a servo drive motor, a transmission ball screw, an upper clamp, a lower clamp, and a displacement encoder. The upper and lower clamps form a tensile path conforming to the geometric relationship of the ASTM D 903 180° peel test. The servo drive motor drives the transmission ball screw to move the clamps at a speed of 300 mm / min. A wideband mechanical sensing module is mechanically coupled to the force-bearing end of the clamps. The wideband mechanical sensing module adopts a piezoelectric force sensor or a high-frequency strain gauge full bridge, and the analog-to-digital converter adopts a 24-bit converter that supports external interrupt control. The ADC, or successive approximation ADC, has a force range of 0N to 50N and sampling noise below 0.005N. The edge intelligent controller uses an FPGA logic gate array or a high-frequency ARM microprocessor, internally configured with a clock interrupt controller, differential operation logic gates, independent registers, a frame register, and SRAM for address mapping. The buffer is configured as a circular buffer, deployed in the FPGA's embedded SRAM or an external low-latency SRAM. The write pointer increments with the sampling clock and wraps around after the last address to continuously retain the tension data for a preset first duration before triggering.

[0022] In the peel test, the test machine body acts as the physical execution entity, fixing the test object and performing constant-speed peeling. The wideband mechanical sensing module acts as the sampling execution entity, acquiring tensile force data at a first frequency and continuously storing it in a buffer. The first frequency is selected from 5000Hz to 20000Hz, preferably 5000Hz. According to the Nyquist sampling theorem, the first frequency can cover the high-frequency extreme value abrupt changes of 1kHz to 2kHz in the stick-slip fracture of porous network structures, avoiding the omission of the true force peak in the early stage of micro-tears by conventional 100Hz sampling. The wideband mechanical sensing module converts each ADC conversion value into tensile force data F(t) according to calibration coefficients. The calibration coefficients are derived from the linear fit of standard weights or standard force sensors, with units of N / count. The circular buffer continuously overwrites the latest tensile force data according to the first frequency, and the buffer capacity meets the requirements. ,in For the first frequency, For the first duration, For single-point bytes; when For 5000Hz, When the time is 5ms and the single point is a 4-byte floating-point number, the effective capacity of the ring buffer for the data before the trigger is not less than 100 bytes. In the engineering implementation, it can be configured to 2KB or 4KB to reserve address alignment space.

[0023] The edge intelligent controller, acting as the main entity for differential calculation, reads continuous tension data from the circular buffer in real time, and performs differential calculations using a preset step size to obtain the differential value, thereby constructing the trigger baseline. The differential value can be calculated according to... calculate, For the first frequency, The preset step size, Take values ​​from 1 to 5. As an equivalent alternative implementation, for the acquisition of differential values ​​and the construction of the trigger baseline, in addition to using direct difference between adjacent tensile data points, the edge intelligent controller can also extract continuous tensile data and apply a sliding least squares fitting with a preset number of points to obtain the data slope as the differential value. Using the tensile data of the first frequency without downsampling directly as the differential calculation benchmark can avoid the millisecond-level phase hysteresis caused by anti-aliasing filtering, enabling the system to trigger a hardware interrupt at the instant of microscopic stick-slip fracture, eliminating the timing misalignment caused by system response lag, ensuring that the extreme force peak and its leading edge of the high-frequency cliff drop are locked in physical timing, and preventing the abrupt extreme value from being overwritten by the write pointer in the circular buffer.

[0024] Synchronizing with the establishment of the trigger baseline, the broadband force sensing module downsamples the tensile force data to output sampled data at a second frequency. The second frequency ranges from 100Hz to 500Hz, preferably 100Hz, while the first frequency is higher than the second frequency. Downsampling employs integer decimation or decimation after finite impulse response anti-aliasing filtering, with a decimation ratio... ;when 5000Hz and At 100Hz, The value is 50. The wideband mechanical sensing module outputs the sampled data to a separate register of the edge intelligent controller for subsequent periodic analysis. The preset tear threshold can be set from 20 N / s to 200 N / s, preferably based on the differential standard deviation of high-frequency noise from the blank test of the standard sample. Calibrated as to This is to ensure that the low-frequency oscillation of the servo screw will not trigger false judgments.

[0025] Before triggering a hardware interrupt, the displacement encoder of the testing machine body, acting as the displacement acquisition execution entity, acquires the current displacement for the peel test and inputs it into the edge intelligent controller. The edge intelligent controller, acting as the locking execution entity, compares the current displacement with a preset pull-out tolerance; when the current displacement is less than the preset pull-out tolerance, the edge intelligent controller locks the monitoring of the trigger baseline to prevent a hardware interrupt. The preset pull-out tolerance is 3mm to 8mm, preferably 5mm, to shield against false drops caused by residual crushing, burrs, or local geometric defects on the end face of the 25mm die punching edge. As an optional implementation, the preset pull-out tolerance can be adjusted according to the width of the object being tested. of to Setting: When the width of the object being measured is 25mm, the preset pull-out tolerance is 2.5mm to 6.25mm. This range corresponds to the displacement range in which the fixture completes end straightening and initial bending moment stabilization.

[0026] like Figure 1 As shown, the system calculates the differential value based on continuous tensile force data and determines whether the differential value changes from positive to negative and whether the absolute value exceeds a preset tearing threshold. If the threshold condition is not met, the system returns along the "No" branch and continues the differential operation. When the edge intelligent controller monitors the trigger baseline and determines that the differential value changes from positive to negative and the absolute value exceeds the preset tearing threshold, the edge intelligent controller triggers a hardware interrupt along the "Yes" branch. The wideband mechanical sensing module, as the interrupt response execution body, responds to the hardware interrupt, stops the scrolling overwrite, and locks the tensile force data in the ring buffer for a preset first duration before the current moment. This locking action preserves the extreme force peak and the leading edge of the peak, preventing the existing numerical interpolation smoothing from flattening the real high-frequency physical peak. The preset first duration is 3ms to 20ms, preferably 5ms, corresponding to at least 25 high-frequency sampling points at 5000Hz sampling, which can cover the local rising segment before the peak formation.

[0027] After a hardware interrupt is triggered, the wideband mechanical sensing module continues to collect tensile data for a preset second duration. It then sequentially concatenates the locked tensile data with the preset second-duration tensile data to generate a mutation frame, which is then exported to a preset frame register. Specifically, during sequential concatenation, based on the natural incrementing rule of the tensile data timestamps, the locked tensile data reflecting the historical extreme force peaks and wavefronts before the hardware interrupt is placed first, followed by the preset second-duration tensile data reflecting the additional data from the drop and climb after the hardware interrupt. This correlation logic eliminates the causal inversion defect caused by misaligned concatenation order, which forces the peak to be placed after the second trough. This ensures the objective continuity of the high-frequency physical force evolution in the time series, guaranteeing that the drop slope conforming to the true fracture mechanics laws can be extracted from the pure curve subsequently.

[0028] As an alternative implementation, when generating a mutation frame, the broadband force sensing module can also logically link and map the physical address segments of the stored and locked tensile data with the physical address segments of the stored tensile data for a preset second duration in ascending order of timestamps, completing the timing connection in a continuous reading manner. This alternative implementation maintains the objective and natural timing of the physical fracture process and eliminates the forced copying and moving of memory data. The preset second duration is between 20ms and 80ms, preferably 45ms; when the preset first duration is 5ms and the preset second duration is 45ms, the total length of the mutation frame is 50ms, which can simultaneously cover the extreme peak, the cliff-like drop, the second trough, and the secondary climbing pattern from the second trough to the secondary peak. The data structure of the mutation frame includes a frame header, a sampling frequency field, a trigger timestamp field, a first duration field, a second duration field, a tensile data array, and a CRC check field. As an optional implementation, the frame header uses 0xA55A, the trigger timestamp uses IEEE1588 PTP nanosecond counter or the controller's local 64-bit monotonic clock, the tension data array uses IEEE 754 single-precision floating-point or Q15.16 fixed-point format, and the CRC check field uses CRC-16 / CCITT to ensure data integrity in the frame register and subsequent curve calculations.

[0029] The edge intelligent controller, acting as the trough analysis execution entity, extracts the timestamps of each first trough within the continuous sampled data and calculates the time difference variance. Since the sampled data at the second frequency (e.g., 100Hz) has already undergone downsampling with its own anti-aliasing filtering effect, high-frequency extreme values ​​are naturally filtered out, and the continuous macroscopic time length retained in its independent register is sufficient to cover the low-frequency mechanical cycle from 1Hz to 50Hz. Therefore, the first trough can be determined by the first-order difference sign in the continuous sampled data changing from negative to positive and the amplitude being lower than the neighborhood mean. The timestamp of the first trough is the time index of the corresponding sampling point within the continuous sampled data. The time difference between adjacent first troughs... Time difference variance When the time difference variance is less than the preset period tolerance, the edge intelligent controller confirms the presence of low-frequency periodic components in the sampling stream from servo motors, drive ball screws, or coupling eccentricity. The preset period tolerance can be from 0.02ms² to 1ms², preferably calibrated according to the upper limit of mechanical period drift calculated based on the drive ball screw lead, servo speed, and stripping speed.

[0030] When the time difference variance is less than the preset period tolerance, the edge intelligent controller, acting as the fundamental frequency calculation execution entity, calculates the fundamental frequency of the continuous sampled data through a preset sliding window. The preset sliding window length is 1000ms to 5000ms (to fully cover the lower limit of the macroscopic single cycle of 1Hz), and the step size is 10ms to 50ms; the fundamental frequency can be calculated from the reciprocal of the interval between adjacent first troughs. The fundamental frequency can be obtained by searching for the maximum spectral peak within the candidate frequency band of mechanical noise using Fast Fourier Transform. As an equivalent alternative implementation, for the calculation of the fundamental frequency, in addition to inverting the first valley interval in the time domain, the edge intelligent controller can also extract continuous sampled data within a preset sliding window, perform autocorrelation function calculations, and determine the fundamental frequency period by searching for the delay time of the first non-zero peak in the autocorrelation sequence.

[0031] The edge intelligent controller generates an inverted sinusoidal envelope based on the fundamental frequency and obtains the timestamps of each first trough. It then adjusts the overall phase of the inverted sinusoidal envelope at each timestamp to the preset extreme value phase to update the phase zeros. The mathematical derivation model of the inverted sinusoidal envelope can be expressed as follows: ,in It is obtained by estimating the amplitude of local peaks and valleys or the root mean square. The fundamental frequency is calculated based on continuous sampling data. This refers to the phase offset, or phase zero, updated with each low-frequency first trough timestamp. To cancel out the mechanical noise floor within the abrupt frame, the inverted envelope must output a reverse maximum compensation at the first trough of the noise floor. Therefore, when updating the phase zero for each first trough, the edge intelligent controller sets the phase zero for each first trough timestamp... The overall phase at that point reaches the preset extreme value corresponding to the phase of the negative sine function, i.e., it is forcibly satisfied. The extreme value correlation logic. At this point, the sine term... This causes the envelope to reach a positive maximum at this moment. This ensures that the positive compensation peak value is aligned with the negative first trough of the macroscopically extracted mechanical periodic component on the time axis. As an equivalent alternative implementation, signal decoupling processing can also be based on the in-phase cosine envelope form, requiring only the alignment of the corresponding overall phase at each first trough timestamp to... This also achieves the technical effect of eliminating fundamental frequency noise. When the mechanical periodic component exhibits slow drift, the phase zero is updated using a phase-locked loop model. ,in This represents the phase error of the first trough.

[0032] The edge intelligent controller, acting as the primary entity for time-domain decoupling, synchronizes the inverted sinusoidal envelope updated after phase zero with the abrupt change frame in the time domain. It then performs point-by-point amplitude addition on the synchronized inverted sinusoidal envelope and the abrupt change frame to generate a superimposed sequence. Time-domain synchronization uses trigger timestamp and sampling sequence number alignment. The specific mathematical implementation logic for point-by-point amplitude addition is as follows: ,in For the j-th tension data point in the mutation frame, This represents the j-th amplitude point of the inverted sinusoidal envelope after phase alignment. The edge intelligent controller filters out periodic components within abrupt frames based on this superimposed sequence and outputs the retained data points as a clean curve. The clean curve preserves the extreme peaks, precipitous drops, second troughs, the climbing section from the second trough to the secondary peak caused by high-frequency fracture, and multiple sawtooth peaks within the climbing section. This improves the signal-to-noise ratio of the target's high-frequency micro-fracture characteristics, ensuring an objective causal data correspondence between subsequent failure mode determination and the microporous network damage action.

[0033] The edge intelligent controller, acting as the main body for material parameter correction, adjusts a preset slope threshold based on the thickness of the measured object to generate a corrected slope, and maps a preset rebound time based on the hardness of the measured object to generate a reconstruction constant. The thickness of the measured object is obtained from a thickness gauge, laser displacement meter, or manual input before testing, while the hardness is measured using a Shore C hardness tester. The preset slope threshold is lowered based on the thickness of the measured object to generate the corrected slope, and the thickness is positively correlated with the magnitude of the reduction. The generated corrected slope can be... Calculation. Based on the hardness of the tested object and a preset rebound time, a reconstruction constant is generated, and hardness is negatively correlated with the reconstruction constant. The generated reconstruction constant can be calculated... Mapping.

[0034] The edge intelligent controller, acting as the feature extraction execution entity, extracts the drop slope from the peak to the second trough of the clean curve, as well as the ramp-up time from the second trough to the secondary peak. The peak represents the local maximum tension point before and after the abrupt frame trigger point; the second trough is the first point after the peak that satisfies the local minimum condition and where the tension decreases by more than 5 times the noise amplitude; and the secondary peak is the first local maximum point after the second trough. The drop slope is calculated as follows: Calculations are made in N / s; climbing time is calculated as follows: Calculation. If there are multiple sawtooth peaks on the climbing section, the edge intelligent controller will determine the peaks based on amplitudes exceeding three times the local noise standard deviation and the interval between adjacent peaks being greater than [missing value]. The rules identify multiple sawtooth peaks to avoid ADC single-point jitter being included in the sawtooth structure. By using ordinal numbers to define the first trough of the extracted fundamental frequency and the second trough representing the microscopic fracture of the pure curve, effective isolation is achieved between the macroscopic mechanical vibration noise and the physical extreme values ​​of microscopic stick-slip fractures at different time scales. This eliminates cross-scale mutual exclusion and addressing collision errors of the underlying algorithm objects, ensuring the logical self-consistency of microscopic stripping feature extraction in terms of physical laws.

[0035] The edge intelligent controller, acting as the failure mode determination entity, determines the failure mode based on the comparison results of the drop slope and the corrected slope, and the ramp time and the reconstruction constant. When the drop slope is greater than the corrected slope and the ramp time is less than the reconstruction constant, the edge intelligent controller determines that interface detachment has occurred. For example... Figure 2The tensile-time graph shown corresponds to a situation where the adhesive layer interface rapidly loses adhesion, and the tensile force drops from the extreme peak to the second trough along the steep tangent marked on the graph within a short period of time. Furthermore, the tested material does not undergo prolonged micropore reconstruction, corresponding to a narrower climbing time interval on the horizontal axis, resulting in a faster climb from the second trough to the secondary peak. Combined with... Figure 3 The tension-time relationship chart shows that when the drop slope is less than or equal to the corrected slope, the ramp-up time is greater than the reconstruction constant, and multiple sawtooth peaks are identified within the ramp-up time interval corresponding to the pure curve, the edge intelligent controller determines that cohesive tearing has occurred. This situation corresponds to segmental tearing of the porous network of the adsorption pad body. The continuous fracture of the micropore walls and the superposition of local rebound form multiple secondary sawtooth peaks framed by the dashed circles in the figure. Compared with interface detachment, its drop slope is relatively gentle and corresponds to an extended ramp-up time on the horizontal axis. As an optional implementation, the determination of interface detachment can be further required that the force drop amplitude from the peak to the second trough is greater than 30% to 70% of the peak value, and the determination of cohesive tearing can be further required that the number of sawtooth peaks is not less than 3 and the amplitude difference between adjacent sawtooth peaks does not exceed 20% of the main peak amplitude, so as to improve the consistency of determination between different batches of wax-free adsorption pads.

[0036] In the calculation of the global average peel force during the peel test, the broadband mechanical sensing module acquires the absolute tensile force corresponding to the current displacement, and the edge intelligent controller, as the bubble identification execution entity, receives the absolute tensile force and the current displacement. When the absolute tensile force falls into a preset void dead zone, and the continuous displacement maintained within the preset void dead zone exceeds a preset displacement threshold, the edge intelligent controller determines that there is a bubble in the segment corresponding to the continuous displacement. The preset void dead zone is preferably an absolute tensile force of less than 0.1N, and the preset displacement threshold is preferably 2mm; these parameters correspond to the unbonded bubble area that may still remain after being pressed and bonded by a 2kg rubber roller. The edge intelligent controller marks the tensile force data of the segment corresponding to the continuous displacement with a preset invalid label, and when calculating the average peel force, it removes the tensile force data based on the physical address mapped by the preset invalid label, thereby avoiding low-value segments caused by bubbles from lowering the average peel force.

[0037] This application also discloses a peel test system for the adhesion of a wax-free absorbent pad, used to implement a peel test method for the adhesion of a wax-free absorbent pad. The system includes a data acquisition module, a mutation frame generation module, a signal decoupling module, and a failure determination module.

[0038] The data acquisition module takes into account the clamp force, current displacement, first frequency, second frequency, preset step size, preset pull-up tolerance, preset dead zone, and preset displacement threshold during the peel test. Its outputs include tensile force data, sampled data, differential value, trigger baseline, current displacement, absolute tensile force, and tensile force data with preset invalid label mapping relationships. The data acquisition module includes a ring buffer configuration unit, a high-frequency sampling unit, a downsampling unit, a register writing unit, a differential value calculation unit, a pull-up locking unit, and a bubble marking unit. The circular buffer configuration unit is used to set the buffer as a circular buffer; the high-frequency sampling unit is used to sample and generate tensile data at a first frequency and overwrite it to the circular buffer; the differential value calculation unit is used to read the continuous tensile data in the circular buffer in real time and perform differential operation in combination with a preset step size to obtain the differential value, thereby constructing the trigger baseline; the downsampling unit is used to perform downsampling synchronously with the rolling over and output the sampled data to an independent register; the pull-up locking unit is used to obtain the current displacement of the peel test and lock the monitoring of the trigger baseline when the current displacement is less than the preset pull-up tolerance to block hardware interruption; the bubble marking unit is used to obtain the absolute tensile force corresponding to the current displacement, mark the segment corresponding to the continuous displacement and remove it during calculation.

[0039] The mutation frame generation module takes as input the differential value output by the data acquisition module, the trigger baseline, the tensile data in the circular buffer, and the preset first and second durations. The mutation frame generation module includes a trigger monitoring unit, a hardware interrupt unit, a buffer locking unit, an append acquisition unit, a sequential splicing unit, and a frame register export unit. The trigger monitoring unit monitors the trigger baseline and generates a trigger condition where the differential value changes from positive to negative and the absolute value of the differential value exceeds a preset tear threshold. The hardware interrupt unit outputs a hardware interrupt based on the trigger condition. The buffer locking unit responds to the hardware interrupt and stops the rolling overwrite to lock the tensile data in the circular buffer for the preset first duration prior to the current moment. The append acquisition unit acquires tensile data for the preset second duration. The sequential splicing unit sequentially splices the locked tensile data with the tensile data for the preset second duration to generate a mutation frame. The frame register export unit exports the mutation frame to a preset frame register.

[0040] The signal decoupling module takes abrupt frame inputs, continuous sampled data, a preset period tolerance, a preset sliding window length, a preset sliding window step size, and a candidate frequency band for mechanical noise. The module includes a trough timestamp extraction unit, a time difference variance calculation unit, a fundamental frequency calculation unit, an inverted sine envelope generation unit, a phase zero-point update unit, a time-domain synchronization unit, a point-by-point amplitude addition unit, and a periodic component filtering unit. The trough timestamp extraction unit extracts the timestamps of each first trough in the continuous sampled data; the time difference variance calculation unit calculates the time difference variance between adjacent first troughs; the fundamental frequency calculation unit calculates the fundamental frequency of the continuous sampled data through a preset sliding window when the time difference variance is less than a preset period tolerance; the inverted sinusoidal envelope generation unit generates an inverted sinusoidal envelope based on the fundamental frequency; the phase zero update unit obtains the timestamps of each first trough and adjusts the corresponding overall phase of the inverted sinusoidal envelope at each timestamp to the preset extreme value corresponding phase to update the phase zero; the time domain synchronization unit performs time domain synchronization between the inverted sinusoidal envelope after updating the phase zero and the abrupt frame; the point-by-point amplitude addition unit performs point-by-point amplitude addition between the synchronized inverted sinusoidal envelope and the abrupt frame to generate a superimposed sequence; the periodic component filtering unit filters out the periodic components in the abrupt frame based on the superimposed sequence and outputs the retained data points as a clean curve.

[0041] The failure determination module takes as input the clean curve, the thickness of the test object, the hardness of the test object, a preset slope threshold, a preset rebound time, and sawtooth peak identification parameters. The failure determination module includes a corrected slope generation unit, a reconstruction constant generation unit, a drop slope extraction unit, a ramp time extraction unit, a sawtooth peak identification unit, and a failure mode output unit. The corrected slope generation unit corrects the preset slope threshold based on the thickness of the test object to generate a corrected slope; the reconstruction constant generation unit maps the preset rebound time based on the hardness of the test object to generate a reconstruction constant; the drop slope extraction unit extracts the drop slope from the peak to the second trough of the clean curve; the ramp time extraction unit extracts the ramp time from the second trough to the secondary peak of the clean curve; the sawtooth peak identification unit identifies multiple sawtooth peaks within the ramp time interval corresponding to the clean curve; and the failure mode output unit outputs interface detachment when the drop slope is greater than the corrected slope and the ramp time is less than the reconstruction constant, and outputs cohesive tear when the determination conditions are met.

[0042] The system also includes a testing machine body, a wideband mechanical sensing module, an edge intelligent controller, memory, a communication interface, and a human-machine interface. The testing machine body includes a servo drive motor, a transmission ball screw, an upper fixture, a lower fixture, a displacement encoder, and a frame. The wideband mechanical sensing module includes a piezoelectric force sensor or a high-frequency strain gauge full-bridge, an analog-to-digital converter (ADC), a sampling clock, and a sensor interface. The ADC has external interrupt pins and data-ready pins. The edge intelligent controller includes an FPGA, an ARM microprocessor, or a heterogeneous combination of an FPGA and an ARM microprocessor. The memory includes SRAM for circular buffering and non-volatile memory.

[0043] The aforementioned virtual functional modules are implemented by a processor reading and executing computer programs from memory. The processor includes an FPGA, an ARM microprocessor, or a combination of both in the edge intelligent controller. The computer programs stored in memory include data acquisition instructions, mutation frame generation instructions, signal decoupling instructions, failure determination instructions, address mapping instructions, and communication output instructions. The FPGA implements ring buffer write pointers, hardware interrupts, differential operations, and frame register handling; the ARM microprocessor implements material parameter correction, base frequency calculation, phase zero-point update, clean curve output, and failure mode output. In a single-processor implementation, a high-frequency ARM microprocessor achieves equivalent data acquisition and processing functions through timer interrupts, DMA, and on-chip SRAM.

[0044] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A peel test method for the adhesion of a wax-free absorbent pad, characterized in that, include: In a peel test performed on the test object, tensile data at a first frequency is acquired and continuously stored in a cache. A differential value is calculated based on the continuous tensile data, and the tensile data is downsampled to output sampled data at a second frequency, wherein the first frequency is greater than the second frequency. When the differential value changes from positive to negative and the absolute value of the differential value exceeds the preset tearing threshold, the tension data of the first preset duration before the current time in the cache is locked, and the locked tension data and the added tension data of the second preset duration are sequentially merged into a mutation frame; Extract the timestamps of each first trough in the continuous sampling data and calculate the time difference variance. When the time difference variance is less than the preset period tolerance, calculate the fundamental frequency of the continuous sampling data through a preset sliding window. Generate an inverted sinusoidal envelope, update the phase zero of the inverted sinusoidal envelope for each of the first valleys based on the fundamental frequency, and time-domain superimpose the inverted sinusoidal envelope after updating the phase zero with the abrupt frame to obtain a clean curve; The preset slope threshold is corrected based on the thickness of the test object to generate a corrected slope, and the preset rebound time is mapped based on the hardness of the test object to generate a reconstruction constant. Extract the drop slope from the peak to the second trough and the climbing time from the second trough to the next peak from the pure curve. The failure mode is determined based on the comparison results of the drop slope and the correction slope, the ramp time and the reconstruction constant.

2. The peel test method for the adhesion of a wax-free adsorption pad according to claim 1, characterized in that, The steps of acquiring tensile force data at a first frequency and storing it in a buffer during a peel test on the test object, calculating the differential value based on the continuous tensile force data, and downsampling the tensile force data to output sampled data at a second frequency include: Set the cache as a circular cache; The tensile data is generated by sampling at the first frequency, and the tensile data is then overwritten into the circular buffer. The continuous tensile data in the circular buffer is read in real time, and a differential operation is performed in combination with a preset step size to obtain the differential value, thereby constructing a trigger baseline; The downsampling is performed synchronously with the rolling over to output the sampled data to a separate register.

3. The peel test method for the adhesion of a wax-free adsorption pad according to claim 2, characterized in that, The step of locking the tension data of a preset first duration prior to the current time in the cache, and sequentially merging the locked tension data with the appended tension data of a preset second duration into a mutation frame, includes: The trigger baseline is monitored, and a hardware interrupt is triggered when it is determined that the differential value changes from positive to negative and the absolute value of the differential value exceeds the preset tearing threshold. In response to the hardware interrupt, the rolling over is stopped to lock the tension data of the preset first duration before the current time in the circular buffer; The tensile data of the preset second duration is collected, and the locked tensile data and the tensile data of the preset second duration are sequentially spliced ​​to generate the mutation frame, which is then exported to the preset frame register.

4. The peel test method for the adhesion of a wax-free adsorption pad according to claim 3, characterized in that, Before triggering the hardware interrupt, the following are included: Obtain the current displacement of the peel test; When the current displacement is less than the preset pull-up tolerance, the monitoring of the trigger baseline is locked to block the hardware interrupt.

5. The peel test method for the adhesion of a wax-free adsorption pad according to claim 4, characterized in that, Also includes: Obtain the absolute tension corresponding to the current displacement; When the absolute tensile force falls into the preset void dead zone, and the continuous displacement maintained in the preset void dead zone exceeds the preset displacement threshold, it is determined that there is an air bubble in the segment corresponding to the continuous displacement. The tensile data of the segment corresponding to the continuous displacement is marked with a preset invalid label, and the tensile data is removed based on the physical address mapped by the preset invalid label when calculating the average peel force.

6. The peel test method for the adhesion of a wax-free adsorption pad according to claim 1, characterized in that, The step of generating an anti-phase sinusoidal envelope and updating the phase zeros of the anti-phase sinusoidal envelope based on the fundamental frequency for each of the first valleys includes: The inverted sinusoidal envelope is generated based on the fundamental frequency; Obtain the timestamps of each of the first troughs; The overall phase of the inverted sine envelope at each of the timestamps is adjusted to the phase corresponding to the preset extreme value, so as to update the phase zero point.

7. The peel test method for the adhesion of a wax-free adsorption pad according to claim 6, characterized in that, The step of temporally superimposing the inverted sinusoidal envelope after updating the phase zero with the abrupt frame to obtain a pure curve includes: The inverted sinusoidal envelope after updating the phase zero point is synchronized in the time domain with the abrupt frame. The synchronized inverted sinusoidal envelope and the abrupt frame are summed point by point to generate a superimposed sequence; Based on the superimposed sequence, the periodic components within the mutated frame are filtered out, and the retained data points are output as the pure curve.

8. The peel test method for the adhesion of a wax-free adsorption pad according to claim 7, characterized in that, The steps of correcting a preset slope threshold based on the thickness of the object under test to generate a corrected slope, and mapping a preset rebound time based on the hardness of the object under test to generate a reconstruction constant, include: The preset slope threshold is lowered based on the thickness of the object being measured to generate the corrected slope, and the thickness of the object being measured is positively correlated with the downward adjustment. The reconstruction constant is generated by mapping the preset rebound time to the hardness of the test object, and the hardness of the test object is negatively correlated with the reconstruction constant.

9. The peel test method for the adhesion of a wax-free adsorption pad according to claim 8, characterized in that, The step of determining the failure mode based on the comparison results of the drop slope and the corrected slope, and the ramp time and the reconstruction constant, includes: When the drop slope is greater than the correction slope and the climbing time is less than the reconstruction constant, it is determined that interface detachment has occurred. When the drop slope is less than or equal to the corrected slope, the ramp time is greater than the reconstruction constant, and multiple sawtooth peaks are identified within the interval of the ramp time corresponding to the pure curve, cohesive tearing is determined to have occurred.

10. A peel test system for the adhesion of a wax-free absorbent pad, characterized in that, A peel test method for achieving the adhesion strength of the wax-free absorbent pad according to any one of claims 1 to 9, the system comprising: The data acquisition module is used to acquire tensile data at a first frequency and store it in a buffer during a peel test performed on the test object, calculate the differential value based on the continuous tensile data, and downsample the tensile data to output sampled data at a second frequency, wherein the first frequency is greater than the second frequency. The mutation frame generation module is used to lock the tension data of a preset first duration before the current time in the cache when the differential value changes from positive to negative and the absolute value of the differential value exceeds a preset tearing threshold, and to sequentially merge the locked tension data with the added tension data of a preset second duration into a mutation frame; The signal decoupling module is used to extract the timestamps of each first valley in the continuous sampling data and calculate the time difference variance. When the time difference variance is less than a preset period tolerance, the fundamental frequency of the continuous sampling data is calculated through a preset sliding window. An inverted sinusoidal envelope is generated, and the phase zero of the inverted sinusoidal envelope is updated for each first valley based on the fundamental frequency. The inverted sinusoidal envelope after updating the phase zero is then superimposed with the abrupt frame in the time domain to obtain a clean curve. The failure determination module is used to correct a preset slope threshold based on the thickness of the test object to generate a corrected slope, and to map a preset rebound time based on the hardness of the test object to generate a reconstruction constant; to extract the drop slope from the peak to the second trough and the climbing time from the second trough to the second peak from the pure curve; and to determine the failure mode based on the comparison results of the drop slope and the corrected slope, and the climbing time and the reconstruction constant.

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