Knock detection system for display detection

Abstract

This invention relates to the field of display device testing and discloses a tapping detection system for display testing, including a trigger detection module, a force feedback tapping excitation module, a multimodal signal synchronous acquisition module, a main control and calculation module, and a data processing module. The trigger detection module detects whether the display has reached the testing station and generates a trigger signal. The force feedback tapping excitation module, responding to the trigger signal, applies a tap to the back panel of the display. It includes a force sensor and a drive controller. The drive controller is used to apply a preset standard tapping force waveform command and the actual tapping force signal fed back by the force sensor. This invention effectively solves the consistency problem caused by the large influence of tapping force and position randomness on the detection results in the prior art by introducing a force feedback closed-loop control tapping excitation unit and combining it with a dynamic benchmark model library based on excitation feature clustering and adaptive decision logic.

Description

Technical Field

[0001] This invention relates to the field of display device testing technology, specifically a tapping detection system for testing displays. Background Technology

[0002] In traditional monitor testing, the impact testing device uses a fixed impact head to tap the screen at a preset force to evaluate the panel's impact resistance. The shortcomings of the traditional device are then analyzed, mainly that it has a single structure and function and cannot flexibly adjust the tapping parameters to adapt to diverse testing scenarios. The existing monitor impact testing device is then introduced, which uses a motor to drive the impact component to achieve automated and repeatable tapping action.

[0003] While existing technologies have improved testing efficiency and consistency, they generally suffer from the problem of fixed and non-replaceable impact head structures. This leads to the conclusion that current devices lack a replaceable impact head structure. Due to the absence of this core structure, it is impossible to easily replace impact heads of different shapes or sizes during testing, making it difficult to simulate diverse contact areas and impact scenarios in reality. For example, it is impossible to realistically reproduce the complex situation where fingertips, styluses, or other foreign objects contact the screen with different areas. This limits the comprehensiveness and practicality of the test results. In actual use, the aforementioned devices suffer from fixed impact head specifications, resulting in incomplete coverage of test scenarios, difficulty in accurately simulating various actual impact conditions, and inability to quickly adapt to new testing requirements due to structural limitations. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a tapping detection system for display testing, which solves the problem that fixed impact head specifications lead to incomplete coverage of test scenarios and difficulty in accurately simulating various actual tapping conditions.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solution: a tapping detection system for display testing, comprising: a trigger detection module, a force feedback tapping excitation module, a multimodal signal synchronous acquisition module, a main control and calculation module, and a data processing module; The trigger detection module is used to detect whether the display has reached the detection station and generate a trigger signal; The force feedback tapping excitation module, in response to the trigger signal, is used to apply a tap to the back panel of the display. It includes a force sensor and a drive controller. The drive controller is used to adjust the tapping action through force closed-loop control according to the preset standard tapping force waveform command and the actual tapping force signal fed back by the force sensor, so that the actual tapping force waveform tracks the standard tapping force waveform. The multimodal signal synchronous acquisition module is used to synchronously acquire the actual impact force signal and multiple physical response signals from the display based on a unified hardware synchronous trigger signal when the impact occurs. The multiple physical response signals include at least vibration signals, electrical signals, sound signals and optical signals. The data processing module is configured to perform the following steps: Based on the tapping detection data of multiple good monitors, excitation feature vectors and response feature vectors are extracted. The excitation feature vectors are clustered to form multiple excitation feature clusters. The statistical benchmark of the response feature vector corresponding to each excitation feature cluster is calculated. A dynamic benchmark model library containing multiple sub-models is constructed. Each sub-model is associated with an excitation feature cluster and its corresponding response feature statistical benchmark. For the display under test, extract the excitation feature vector and response feature vector of the current tap; match the current excitation feature vector with the excitation feature clusters of each sub-model in the dynamic benchmark model library to determine the matching sub-model; compare the current response feature vector with the response feature statistical benchmark in the matching sub-model, and determine whether the display is qualified based on the comparison result.

[0006] Preferably, in the online detection step of the data processing module, the step of "comparing the current response feature vector with the response feature statistical benchmark in the matching sub-model" specifically includes: Calculate the distance between the current activation feature vector and the center of the activation feature cluster of the matching sub-model; Based on the distance, the normal fluctuation range in the statistical benchmark of the response features of the matching sub-model is adaptively adjusted to obtain the adjusted decision threshold. Each component of the current response feature vector is compared with the corresponding component of the mean response feature vector of the matching sub-model. If the deviation of any component from the mean exceeds the corresponding threshold in the adjusted decision threshold, it is determined to be a single feature abnormality.

[0007] Preferably, the step of "comparing the current response feature vector with the response feature statistical benchmark in the matching sub-model" further includes: Calculate the Mahalanobis distance between the current response feature vector and the mean response feature vector of the matching sub-model, wherein the Mahalanobis distance is calculated based on the response feature covariance matrix of the matching sub-model; If the Mahalanobis distance exceeds the preset association decision threshold, it is determined to be an abnormal multi-parameter association.

[0008] Preferably, the trigger detection module is a through-beam infrared photoelectric switch, with its transmitter and receiver positioned opposite each other on both sides of the detection station, so that the back panel of the display blocks the infrared beam when it reaches the station to generate the trigger signal.

[0009] Preferably, the force feedback striking excitation module further includes a synchronization trigger circuit for generating the unified hardware synchronization trigger signal, wherein the synchronization trigger circuit generates a trigger pulse when the drive controller starts to execute the striking action; The multimodal signal synchronous acquisition module includes a multi-channel synchronous data acquisition card, which receives the trigger pulse as an external trigger signal to synchronously start the acquisition of the actual impact force signal and all multi-channel physical response signals.

[0010] Preferably, a tapping detection device for display testing, the device employing the above-described system for operation, includes a base, a platform fixedly connected to the top of the base, a grooved frame fixedly connected to the outer side of the platform, a pneumatic swing cylinder fixedly connected to the outer side of the grooved frame, a swing rod fixedly connected to the bottom of the pneumatic swing cylinder, a replacement mechanism provided at the bottom end of the swing rod, and an adjustment mechanism provided at the top of the platform.

[0011] Preferably, the replacement mechanism includes a connecting rod, the top of which is fixedly connected to the bottom end of the pendulum rod, a bonding piece is fixedly connected to the outer side of the connecting rod, a connecting rod is fixedly connected to the outer side of the bonding piece, a grooved post is fixedly connected to the outer side of the connecting rod, a rubber ring is fixedly connected to the outer side of the grooved post, and a pendulum ball is slidably connected to the outer side of the grooved post.

[0012] Preferably, the replacement mechanism further includes a bolt, the outer side of which is fixedly connected to the outer side of the grooved column, a through groove is provided on the inner side of the pendulum ball, an inner groove rod is slidably connected to the inner side of the pendulum ball, and a bolt is threadedly connected to the outer side of the inner groove rod.

[0013] Preferably, the adjustment mechanism includes a rotating shaft, with both ends of the rotating shaft rotatably connected to the outside of the machine base. A screen mounting frame is rotatably connected to the outside of the rotating shaft, and a limit frame is rotatably connected to the inside of the screen mounting frame. A stop frame is fixedly connected to the limit frame.

[0014] Preferably, a foam platform is fixedly connected to the top of the machine, and the foam platforms are symmetrically distributed along the central axis of the machine.

[0015] This invention provides a tapping detection system for display testing. It has the following advantages: 1. This invention effectively solves the consistency problem caused by the significant influence of the randomness of the striking force and position on the detection results in existing technologies by introducing a force feedback closed-loop control striking excitation unit and combining it with a dynamic benchmark model library based on excitation feature clustering and adaptive decision logic. Force closed-loop control ensures a high degree of consistency in the mechanical input for each strike, providing a physical basis for standardized detection. At the data processing level, the system does not compare all detection results with a single fixed threshold, but dynamically selects the most matching benchmark model based on the excitation characteristics of each actual strike, and adaptively fine-tunes the decision threshold based on the subtle distance between the excitation characteristics and the model center. This method allows the detection system to tolerate and correct excitation fluctuations caused by minor deviations in the mechanical actuator or environmental disturbances, thereby maintaining high repeatability and reliability of judgments during long-term production line operation and reducing misjudgments and missed judgments caused by benchmark drift.

[0016] 2. This invention achieves strict synchronous acquisition of multimodal signals through a hardware synchronous triggering mechanism. Based on this, it employs a comprehensive analysis method that includes single-feature and multi-parameter correlation judgments, greatly improving the depth and accuracy of fault diagnosis. Traditional impact detection relies on manual judgment of a single phenomenon, while this invention can simultaneously capture the display's response in multiple dimensions, including mechanical, electrical, acoustic, and optical aspects, at the moment of impact and for a period afterward, and accurately analyze the temporal correlation of these signals. Through multi-parameter correlation judgments using algorithms such as Mahalanobis distance, the system can identify potential defects or coupled faults where all individual features are within acceptable limits, but the combination of multiple feature parameters deviates from the normal state. This objective and quantitative analysis based on multi-dimensional information fusion not only transforms detection from subjective experience-driven judgment to objective data-driven analysis, but also discovers early and hidden quality hazards, achieving a more comprehensive assessment of the display's structural integrity and electrical connection reliability.

[0017] 3. This invention, by incorporating a replaceable mechanism including a detachable connecting rod, link, grooved post, and pendulum ball, enables the impact testing device to easily replace impact modules of different specifications. Specifically, bolted connections and threaded engagements facilitate rapid connection and separation of the pendulum ball and transmission structure. Simultaneously, the flexible fixing of the rubber ring and the guiding effect of the grooved post ensure the stability of component connections during replacement while reducing the difficulty of disassembly and assembly. This structural design effectively enhances the device's adaptability to different testing requirements and simplifies maintenance and adjustment operations. Attached Figure Description

[0018] Figure 1 This is a flowchart illustrating the system operation of the present invention. Figure 2 This is a perspective view of the tapping detection device for display testing according to the present invention; Figure 3This is a front view of the tapping detection device for display testing according to the present invention; Figure 4 This is a cross-sectional view of the replacement mechanism of the tapping detection device for display testing according to the present invention.

[0019] The components include: 1. base; 2. machine platform; 3. groove frame; 4. pneumatic swing cylinder; 5. swing rod; 6. foam platform; 7. replacement mechanism; 701. connecting rod; 702. bonding piece; 703. connecting rod; 704. groove column; 705. rubber ring; 706. pendulum ball; 707. bolt; 708. through groove; 709. inner groove rod; 8. adjustment mechanism; 801. gear frame; 802. limit frame; 803. screen holder; 804. rotating shaft. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments.

[0021] It should be noted that, unless otherwise defined, the technical or scientific terms used in this invention should have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0022] Example: Please see the appendix Figure 1 - Appendix Figure 4 The present invention provides a tapping detection system for display detection, comprising a trigger detection module, a force feedback tapping excitation module, a multimodal signal synchronous acquisition module, and a main control and calculation module.

[0023] The trigger detection module automatically determines whether the display has reached the predetermined tapping position and initiates the detection process. This module includes at least one through-beam infrared photoelectric switch. The transmitter and receiver of this switch are mounted opposite each other on either side of the detection station, and the path of its infrared beam passes through the preset tapping position on the back panel of the display. When the display moves to this position and blocks the beam, the receiver generates a level transition signal. This signal is sent to the main control and computing module as a trigger signal indicating that the display is in position. Upon receiving this signal, the main control module controls the subsequent tapping excitation module to operate.

[0024] The force feedback impact excitation module generates standardized mechanical impact excitation for a pre-triggered and positioned display. This module consists of a precision electric actuator, a force sensor, a drive controller, and an impact head. The force sensor is installed between the impact head and the actuator output or integrated within the impact head to measure the impact force acting on the display in real time. The drive controller receives standard impact force waveform commands from the main control module and receives real-time feedback signals from the force sensor. Through a built-in force closed-loop control algorithm, the drive controller adjusts the movement of the electric actuator in real time, ensuring that the actual impact force waveform tracks the preset standard waveform. The force sensor signal used for force closed-loop control is also output as a key "excitation signal" and connected to the multi-modal signal synchronous acquisition module.

[0025] The multimodal signal synchronous acquisition module is used to acquire the display's response signals in multiple physical dimensions at the same moment a tap occurs. This module consists of various physical sensors, signal conditioning circuitry, a multi-channel synchronous data acquisition card, and a synchronous triggering circuit. The sensor array includes: An accelerometer, attached to the bezel or back panel of a display, is used to measure mechanical vibrations; The current probe and voltage probe are connected to the power supply circuit of the display to measure current and voltage transients; A microphone, placed near the display, is used to collect knocking sounds; Visible light optical sensors, such as high-speed industrial cameras or photodiodes, are aligned with the screen to detect image stability. The excitation force signal from the force feedback impact excitation module, after being preprocessed by the signal conditioning circuit of all sensors, is connected to different input channels of the same multi-channel synchronous data acquisition card. At the same moment that the impact action begins, the force feedback impact excitation module generates a hardware synchronous trigger pulse and sends it to the external trigger port of the data acquisition card. When the data acquisition card receives the edge of the trigger pulse, it uses its internal unified high-stability clock source to simultaneously start sampling of all input channels. This design ensures that the excitation force signal and all response signals (vibration, current, sound, optics) share the exact same sampling clock start point, thereby obtaining a data sequence with a unified and accurate time base, providing a basis for subsequent analysis of the temporal causal relationship between signals.

[0026] The main control and computing module is the core of the system's control and data processing, typically comprised of an industrial control computer. This module connects via a communication bus to the drive controllers of the trigger detection module and the force feedback impact excitation module, as well as the data acquisition card of the multimodal signal synchronous acquisition module. The industrial control computer runs the system's control software, data processing algorithms, and human-machine interface. The control software coordinates the entire detection process, including receiving trigger signals, controlling impact excitation, and commanding synchronous acquisition. The data processing algorithm performs computational tasks such as signal preprocessing, feature extraction, model matching, and decision-making. Communication between the industrial control computer and external devices uses a standard industrial configuration.

[0027] After signal acquisition is completed on the hardware platform, the system enters the data processing flow. This flow includes signal preprocessing, feature parameter extraction, offline construction of a dynamic benchmark model library, and online adaptive detection and decision-making.

[0028] Signal preprocessing involves manipulating the raw acquired signals to improve signal quality. For time-domain signals acquired by acceleration, current, voltage, sound, and optical sensors, filtering is typically required to remove noise. For example, a band-stop filter is applied to current signals to eliminate power frequency interference, while a band-pass filter is applied to sound signals to retain frequency bands relevant to abnormal noise. Simultaneously, the voltage values ​​output by the sensors need to be converted into physically meaningful quantities, such as acceleration or sound pressure levels, based on their sensitivity coefficients. These filtering and calibration conversion methods are well-known techniques in the field of signal processing.

[0029] Feature parameter extraction is the process of calculating a set of quantitative indicators, or feature vectors, from the preprocessed signal to characterize the characteristics of the tapping excitation and the display response.

[0030] Excitation feature extraction is performed on the actual impact force signal synchronously acquired from the force feedback impact excitation module. Time-domain and frequency-domain analysis is conducted on this force signal to extract key features that constitute an excitation feature vector. Specifically extractable features include time-domain peak force, force impulse, frequency-domain dominant frequency, and the proportion of energy in a specific frequency band to the total energy. The excitation feature vector is a set of these feature values. Those skilled in the art can add, remove, or replace other time- and frequency-domain features as needed.

[0031] Response feature extraction is performed on synchronous signals acquired from acceleration, current, sound, and optical sensors. Feature parameters related to display quality are extracted from each signal, collectively forming a response feature vector. For example, the total vibration energy or amplitude at a specific resonant frequency can be extracted from the acceleration signal; the current drop depth and recovery time can be extracted from the current signal; the sound pressure level within a preset abnormal noise band can be extracted from the sound signal; and the maximum transient amplitude of screen brightness or flicker duration can be extracted from the optical sensor signal. The response feature vector is a collection of these feature values. Feature terms can be selected and defined according to actual detection needs. The types, quantities, and calculation methods of the response features extracted in the online detection phase must be completely consistent with those used in the offline modeling phase.

[0032] The construction of the dynamic benchmark model library was completed offline, requiring a certain number of verified, qualified monitors as good samples. Multiple standard taps were performed on each good sample, and each tap yielded a pair of excitation and response feature vectors following the aforementioned process, forming the training dataset. Cluster analysis was then performed on all the excitation feature vectors in this dataset, for example using... Clustering algorithms divide all activation features into There are several clusters. Each cluster has a central vector. The purpose of cluster analysis is to group features with similar tapping excitation patterns into the same class. For each excitation feature cluster, all samples belonging to that cluster are identified. The statistical properties of the set of response feature vectors corresponding to these samples are calculated, including the mean vector and covariance matrix. Simultaneously, the standard deviation vector of the cluster's response features is calculated, where each component is the square root of the corresponding diagonal element of the covariance matrix, characterizing the dispersion of each feature dimension. Ultimately, the dynamic benchmark model library consists of... The model library consists of several sub-models, each containing: the activation cluster center vector, the response feature mean vector, the response feature covariance matrix, and the response feature standard deviation vector. The model library is stored as a data file.

[0033] Online adaptive detection and decision-making is the process by which the system performs real-time detection on the display under test. When the display under test is triggered by a tap, the system synchronously acquires the excitation force signal and various response signals. After the same preprocessing and feature extraction steps, the system obtains the excitation feature vector and response feature vector for this detection.

[0034] The first step is dynamic model matching. The distance between the detected activation feature vector and the center vectors of all activation clusters in the model library is calculated, typically using Euclidean distance. The model with the smallest distance is selected as the matching model.

[0035] The second step is adaptive decision-making. This step involves two decision-making logics.

[0036] In single-feature decision-making, each component of the response feature vector is compared with the corresponding component of the baseline mean vector in the matching model. To account for the impact of subtle differences in the stimulus itself on the decision threshold, an adaptive adjustment is introduced. The adjusted decision threshold vector is then calculated. : In the formula, It is the standard deviation vector of the response features stored in the matching model. It is a preset small positive coefficient. This is the matching distance calculated in the previous step. For the... If a feature is satisfied If so, then the feature is determined to be abnormal. This is the confidence coefficient, usually taken as 2 or 3. It is the first of the mean vectors of the matching model. One portion, yes The Each component.

[0037] In multi-parameter correlation decision-making, the feature vector of the current response is calculated. Relative to the matching baseline mean vector Mahalanobis distance : In the formula, This is the response feature covariance matrix stored in the matching model. Mahalanobis distance takes into account the correlation between feature parameters. If If the value exceeds a threshold set according to the chi-square distribution, it is judged as an anomaly in multi-parameter association. The threshold is determined based on the dimension of the response feature vector and the preset significance level.

[0038] The final system decision logic is as follows: if any feature in the single-feature decision is judged as abnormal, or if the multi-parameter correlation decision is judged as abnormal, then the tapping test is deemed unqualified; otherwise, it is deemed qualified. The system outputs the test results and stores all relevant data from this test along with the identification information of the display under test for traceability.

[0039] The system integration and workflow control section defines how the various hardware modules work together and the specific steps for automated testing.

[0040] The infrared photoelectric switch of the trigger detection module, the force feedback impact excitation module, the multi-modal signal synchronous acquisition module, and the main control computing module are connected via an industrial bus or dedicated network. Connection. The detection control program running on the main control computing module is responsible for coordinating the entire process. The status of the infrared photoelectric switch is periodically read by the main control module. When the switch status changes from "unobstructed" to "obstructed" and remains stable for a preset time, the main control module determines that the display is correctly positioned at the detection station.

[0041] The main control module then sends a start command and preset force waveform parameters to the drive controller of the force feedback impact excitation module. Simultaneously, the main control module commands the data acquisition card of the multi-modal signal synchronous acquisition module to enter a "waiting for external trigger" state. While sending the impact start command, the main control module also generates a transistor-to-transistor logic level hardware synchronous trigger pulse through a digital output port or a dedicated trigger circuit, and sends it to the external trigger input port of the data acquisition card.

[0042] The drive controller controls the actuator to perform the striking action. When the data acquisition card receives the rising edge of the hardware synchronization trigger pulse, it immediately starts synchronous data acquisition of all configured channels, recording the striking force, vibration, current, voltage, sound, and optical signals for a preset acquisition time.

[0043] After data acquisition, the main control module reads all waveform data from the data acquisition card and calls the data processing algorithm. The algorithm performs signal preprocessing and excitation and response feature extraction. The extracted excitation feature vector is used to match with the loaded dynamic benchmark model library. The matching process calculates the Euclidean distance between the excitation feature and the center of each excitation cluster in the model library, and selects the benchmark model with the smallest distance.

[0044] The system executes adaptive decision logic based on the matched baseline model. The decision process uses formulas for calculation. For single-feature decisions, an adjustment threshold is calculated. ,in It is the first in the matching model The standard deviation of each response feature It is a preset adjustment coefficient. This is the Euclidean distance between the current activation feature and the center of the matching model cluster. If any feature satisfies... If so, the item is deemed abnormal. For associated decisions, the Mahalanobis distance is calculated. ,like > Then the association is determined to be abnormal, where The threshold is determined based on the chi-square distribution and the preset significance level.

[0045] The system summarizes the judgment results. If no abnormalities are found, the result is qualified; if any abnormality occurs, the result is unqualified. The main control module sends the qualified or unqualified result signal to the production line's programmable logic controller (PLC) through the digital output port to control subsequent actions such as sorting. If an error occurs during data processing, such as abnormal signal acquisition, feature extraction failure, or inability to match a valid baseline model, the system will determine that the detection has failed and output a specific fault code. Simultaneously, an audible and visual alarm will be activated to prompt operator intervention.

[0046] The detection control program generates a structured detection record. This record includes the serial number of the display under test, the detection time, the final result, the anomaly type code, the matched model number, and an index pointing to the original waveform data and feature vectors. The record is then written to a database.

[0047] The human-machine interface provides status monitoring, parameter configuration, result query, and data traceability functions. Operators can start and stop the system, manually trigger detection, adjust decision thresholds, and query historical records through the interface. The interface is implemented based on conventional industrial configuration software.

[0048] The dynamic baseline model library supports updates. When a product changes, new batches of good product data can be collected through the "model learning mode" to re-perform clustering and statistical calculations, generating a new model library. The old and new libraries can be switched based on the product model.

[0049] A tapping test device for display testing, employing the aforementioned system for operation, is characterized by comprising a base 1, which provides fundamental support and rigid fixation for the entire device, ensuring overall stability and shock resistance during operation. A platform 2 is fixedly connected to the top of the base 1, supporting and integrating various functional modules, providing standardized installation references and operating planes for the motion mechanism and testing components. A grooved frame 3 is fixedly connected to the outer side of the platform 2, and a pneumatic swing cylinder 4 is fixedly connected to the outer side of the grooved frame 3. The pneumatic swing cylinder 4 serves as an automated power source, outputting controllable reciprocating swing. The torque drives the striking action to be executed cyclically at a preset frequency. The bottom of the pneumatic swing cylinder 4 is fixedly connected to the swing rod 5. The swing rod 5 is used to convert the rotation and swing of the pneumatic swing cylinder 4 into the arc trajectory of the end striking point, so as to realize the smooth transmission and amplification of the torque. The bottom of the swing rod 5 is provided with a replacement mechanism 7. The replacement mechanism 7 is used to realize the quick disassembly and assembly and specification replacement of the striking contact end to adapt to the impact requirements of different test standards or different material displays. The top of the machine 2 is provided with an adjustment mechanism 8. The adjustment mechanism 8 is used to flexibly adjust the test tilt angle and spatial position of the display to simulate the multi-dimensional force state under real use scenarios. The replacement mechanism 7 includes a connecting rod 701, which connects the pendulum rod 5 and the bonding piece 702. The top of the connecting rod 701 is fixedly connected to the bottom end of the pendulum rod 5. The bonding piece 702 is fixedly connected to the outside of the connecting rod 701. The bonding piece 702 is used to fix one side of the pendulum ball 706. The outside of the bonding piece 702 is fixedly connected to a connecting rod 703. The outside of the connecting rod 703 is fixedly connected to a grooved post 704. The outside of the grooved post 704 is fixedly connected to a rubber ring 705. The grooved post 704 is fixedly connected to the connecting rod 703. The middle groove of the grooved post 704 is used to fix the rubber ring 705. The outside of the grooved post 704 is slidably connected to the pendulum ball 706. The pendulum ball 706 is the direct unit of display contact during display testing. The replacement mechanism 7 also includes a bolt 707, the outer side of which is fixedly connected to the outer side of the grooved column 704. The bolt 707 and the grooved column 704 are connected to each other by threads, which is used to connect the pendulum ball 706 to the pendulum rod 5. A through groove 708 is provided on the inner side of the pendulum ball 706. The groove 708 is the embedding channel of the grooved column 704. An inner grooved rod 709 is slidably connected to the inner side of the pendulum ball 706. The outer side of the inner grooved rod 709 is threadedly connected to the bolt 707. The adjustment mechanism 8 includes a rotating shaft 804, which serves as the rotation center pivot for angle adjustment, enabling the screen holder to smoothly pitch and deflect around a fixed axis. Both ends of the rotating shaft 804 are rotatably connected to the outside of the machine tool 2. The outside of the rotating shaft 804 is rotatably connected to the screen holder 803, which is used to directly clamp and firmly support the display under test, ensuring that the test surface is aligned with the center of the preset tapping trajectory. The inside of the screen holder 803 is rotatably connected to a limiting frame 802, which works in conjunction with a stop frame 801 to fix the angle. The limiting frame 802 is fixedly connected to the stop frame 801, which provides multi-level angle locking to ensure that the display can be stably locked and not deviated after being adjusted to the target posture. A foam platform 6 is fixedly connected to the top of the machine 2. The foam platform 6 is used to flexibly support the display under test, absorb residual vibration and prevent hard scratch damage to the bottom of the display during the test. The foam platform 6 is symmetrically distributed on the central axis of the machine 2. When the tapping detection device for display testing in this invention needs to be replaced with different tapping modules to meet testing requirements during daily use, a Phillips screwdriver is used to align with the Phillips head groove on the embedded rod 709 and rotate it clockwise to dislodge the embedded rod 709 from the bolt 707. Then, the connecting rod 701 located on the other side of the pendulum ball 706 is pulled out. The connecting rod 703 is indirectly connected to the connecting rod 701. The connecting rod 703 is provided with a fixing groove to fix the rubber ring 705. When the connecting rod 701 is pulled out, the rubber ring 705 can be easily removed from the fixing groove due to its flexibility. The pendulum ball 706 mentioned here is not limited to a spherical shape, but can also be of different shapes. After the pendulum ball 706 is separated from the connecting rod 701, a pendulum ball of a different specification can be replaced, and the installation can be completed by reversing the above operation.

[0050] The above formulas are all dimensionless calculations. The formulas are derived from software simulations based on a large amount of collected data to obtain the most recent real-world results. The preset parameters in the formulas are set by those skilled in the art according to the actual situation.

[0051] The above embodiments can be implemented, in whole or in part, by software, hardware, firmware, or any other combination thereof. When implemented in software, the above embodiments can be implemented, in whole or in part, as a computer program product. Those skilled in the art will recognize that the modules and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution.

[0052] The modules described as separate components may or may not be physically separate. The components shown as modules may or may not be physical modules; they may be located in one place or distributed across multiple network modules. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0053] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application.

Claims

1. A tapping detection system for display testing, characterized in that, include: Trigger detection module, force feedback impact excitation module, multimodal signal synchronous acquisition module, main control and calculation module, and data processing module; The trigger detection module is used to detect whether the display has reached the detection station and generate a trigger signal; The force feedback tapping excitation module, in response to the trigger signal, is used to apply a tap to the back panel of the display. It includes a force sensor and a drive controller. The drive controller is used to adjust the tapping action through force closed-loop control according to the preset standard tapping force waveform command and the actual tapping force signal fed back by the force sensor, so that the actual tapping force waveform tracks the standard tapping force waveform. The multimodal signal synchronous acquisition module is used to synchronously acquire the actual impact force signal and multiple physical response signals from the display based on a unified hardware synchronous trigger signal when the impact occurs. The multiple physical response signals include at least vibration signals, electrical signals, sound signals and optical signals. The data processing module is configured to perform the following steps: Based on the tapping detection data of multiple good monitors, excitation feature vectors and response feature vectors are extracted. The excitation feature vectors are clustered to form multiple excitation feature clusters. The statistical benchmark of the response feature vector corresponding to each excitation feature cluster is calculated. A dynamic benchmark model library containing multiple sub-models is constructed. Each sub-model is associated with an excitation feature cluster and its corresponding response feature statistical benchmark. For the display under test, extract the excitation feature vector and response feature vector of the current tap; match the current excitation feature vector with the excitation feature clusters of each sub-model in the dynamic benchmark model library to determine the matching sub-model; compare the current response feature vector with the response feature statistical benchmark in the matching sub-model, and determine whether the display is qualified based on the comparison result.

2. The tapping detection system for display testing according to claim 1, characterized in that, In the online detection step of the data processing module, the step of "comparing the current response feature vector with the response feature statistical benchmark in the matching sub-model" specifically includes: Calculate the distance between the current activation feature vector and the center of the activation feature cluster of the matching sub-model; Based on the distance, the normal fluctuation range in the statistical benchmark of the response features of the matching sub-model is adaptively adjusted to obtain the adjusted decision threshold. Each component of the current response feature vector is compared with the corresponding component of the mean response feature vector of the matching sub-model. If the deviation of any component from the mean exceeds the corresponding threshold in the adjusted decision threshold, it is determined to be a single feature abnormality.

3. The tapping detection system for display testing according to claim 1, characterized in that, The phrase "comparing the current response feature vector with the response feature statistical benchmark in the matching sub-model" also includes: Calculate the Mahalanobis distance between the current response feature vector and the mean response feature vector of the matching sub-model, wherein the Mahalanobis distance is calculated based on the response feature covariance matrix of the matching sub-model; If the Mahalanobis distance exceeds the preset association decision threshold, it is determined to be an abnormal multi-parameter association.

4. The tapping detection system for display testing according to claim 1, characterized in that, The trigger detection module is a through-beam infrared photoelectric switch, with its transmitter and receiver positioned opposite each other on both sides of the detection station, so that the back panel of the display blocks the infrared beam when it reaches the station to generate the trigger signal.

5. The tapping detection system for display testing according to claim 1, characterized in that, The force feedback tapping excitation module also includes a synchronization triggering circuit for generating the unified hardware synchronization triggering signal, wherein the synchronization triggering circuit generates a trigger pulse when the drive controller starts to execute the tapping action; The multimodal signal synchronous acquisition module includes a multi-channel synchronous data acquisition card, which receives the trigger pulse as an external trigger signal to synchronously start the acquisition of the actual impact force signal and all multi-channel physical response signals.

6. A tapping detection device for display testing, the device operating using the system as described in claim 1, characterized in that, The machine includes a base (1), a platform (2) is fixedly connected to the top of the base (1), a groove frame (3) is fixedly connected to the outside of the platform (2), a pneumatic swing cylinder (4) is fixedly connected to the outside of the groove frame (3), a swing rod (5) is fixedly connected to the bottom of the pneumatic swing cylinder (4), a replacement mechanism (7) is provided at the bottom end of the swing rod (5), and an adjustment mechanism (8) is provided at the top of the platform (2).

7. The tapping detection device for display testing according to claim 6, characterized in that, The replacement mechanism (7) includes a connecting rod (701), the top of which is fixedly connected to the bottom end of the swing rod (5). A fitting piece (702) is fixedly connected to the outside of the connecting rod (701), a connecting rod (703) is fixedly connected to the outside of the fitting piece (702), a grooved column (704) is fixedly connected to the outside of the connecting rod (703), a rubber ring (705) is fixedly connected to the outside of the grooved column (704), and a pendulum ball (706) is slidably connected to the outside of the grooved column (704).

8. The tapping detection device for display testing according to claim 7, characterized in that, The replacement mechanism (7) also includes a bolt (707), the outer side of which is fixedly connected to the outer side of the groove column (704), the inner side of the pendulum ball (706) is provided with a through groove (708), the inner side of the pendulum ball (706) is slidably connected with an inner groove rod (709), and the outer side of the inner groove rod (709) is threadedly connected with a bolt (707).

9. The tapping detection device for display testing according to claim 6, characterized in that, The adjustment mechanism (8) includes a rotating shaft (804), the two ends of which are rotatably connected to the outside of the machine base (2). A screen holder (803) is rotatably connected to the outside of the rotating shaft (804), and a limit frame (802) is rotatably connected to the inside of the screen holder (803). A gear position frame (801) is fixedly connected to the limit frame (802).

10. The tapping detection device for display testing according to claim 6, characterized in that, A foam platform (6) is fixedly connected to the top of the machine base (2), and the foam platform (6) is symmetrically distributed along the central axis of the machine base (2).

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