An automated detection system and method for a thin film pressure sensor array

Abstract

The application provides an automatic detection system and method for a thin film pressure sensor array, which comprises a multi-axis motion module for providing displacement; a standard pressure detection unit for applying standard pressure to the thin film sensor array to be detected; a visual positioning module for automatically identifying a reference mark on the thin film sensor array to be detected fixed on an adaptive fixing module and calculating a position deviation; a central control unit for correcting the motion track of the multi-axis motion module according to the position deviation; controlling the multi-axis motion module to drive the standard pressure detection unit to move to a target test point and performing force feedback closed-loop control so that the standard pressure detection unit contacts the sensitive unit of the thin film sensor array to be detected at a preset target pressure value; in the pressure maintaining stage, the output signal of the thin film sensor to be detected is collected, the steady state value is predicted before the physical steady state is reached based on an embedded steady state predictor module, and the steady state value is corrected in real time based on an embedded hysteresis compensation module.

Description

Technical Field

[0001] This invention relates to the field of sensor detection technology, and specifically to an automatic detection system and method for a thin-film pressure sensing array. Background Technology

[0002] Thin-film pressure sensor arrays are widely used in smart wearables, robotic electronic skin, and medical monitoring due to their thinness, flexibility, and ability to conform to curved surfaces. However, thin-film sensor arrays typically contain dozens or even hundreds of sensing elements, requiring calibration and consistency testing of the parameters of each element during the manufacturing process.

[0003] Existing detection technologies suffer from the following main problems: First, traditional equipment often uses a single-point standard sensor in conjunction with a three-axis slide stage for point-to-point serial testing. For high-density arrays, the testing time is extremely long, failing to meet mass production cycle requirements. Second, some devices use clamps to fix the film, which is not secure for warped or irregularly shaped films. Third, existing equipment often relies on manual adjustment of the sample position using clamps, which is not only cumbersome but also introduces human alignment errors, making it difficult to ensure that the probe accurately falls on the center of the sensitive unit. In addition, traditional methods often use "positioning shift" control (i.e., moving to a fixed Z-coordinate), which leads to inconsistent actual contact pressure due to uneven film thickness or differences in substrate flatness; and rigid probes are prone to damaging the soft film surface. Finally, there is a lack of specialized compensation algorithms for the hysteresis and creep effects unique to thin-film sensors, resulting in low test data accuracy and often requiring long waiting times for the physical state to reach, further reducing efficiency.

[0004] Therefore, it is particularly urgent to develop an automated testing system with automatic alignment, flexible constant force loading, efficient fixation, and intelligent data compensation. Summary of the Invention

[0005] This invention provides an automatic detection system and method for thin-film pressure sensing arrays, aiming to solve the problems of low efficiency, poor accuracy, easy sample damage, and high dependence on manual labor in the prior art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: In a first aspect, an automatic detection system for a thin-film pressure sensing array includes: Frame 1 serves as the main support structure for the system; Multi-axis motion module 2, mounted on frame 1, is used to provide displacement; The standard pressure detection unit 3 is installed at the end of the multi-axis motion module 2 and is used to apply standard pressure to the thin film sensor array under test and collect reference data. The adaptive fixing module 4 is mounted on the frame 1 and located below the standard pressure detection unit 3. It is used to fix the thin film sensor array under test. The visual positioning module 5, mounted on the frame 1, is used to automatically identify the reference marks on the sensor array of the thin film under test and calculate the position deviation; The central control unit 6 is communicatively connected to the multi-axis motion module 2, the standard pressure detection unit 3, the adaptive fixation module 4, and the vision positioning module 5, respectively; the central control unit 6 is configured as follows: Based on the positional deviation, the motion trajectory of the multi-axis motion module 2 is corrected; the multi-axis motion module 2 is controlled to drive the standard pressure detection unit 3 to move to the target test point, and force feedback closed-loop control is executed so that the standard pressure detection unit 3 contacts the sensitive unit of the thin film sensor array under test with a preset target pressure value; During the pressure holding stage, the output signal of the thin film sensor under test is acquired. Based on the built-in steady-state prediction submodule, the steady-state value is predicted before the physical steady state is reached, and the steady-state value is corrected in real time based on the built-in hysteresis compensation submodule.

[0007] Preferably, the multi-axis motion module 2 supports two operating modes: In single-point scanning mode, the standard pressure detection unit 3 is controlled to move point by point to the center position of each sensitive unit on the thin film sensor array under test for testing; in parallel array mode, the standard pressure detection unit 3 is a miniaturized standard sensor array module, which is controlled to move to several preset coverage areas to complete the parallel testing of multiple sensitive units at one time.

[0008] Preferably, the standard pressure detection unit 3 includes a flexible silicone ball head probe 31 for direct contact with the film under test and a force sensor 33; a rigid force transmission core 32 is embedded in the center of the flexible silicone ball head probe 31; a cylindrical connecting rod is provided at the tail of the transmission core, extending out of the flexible silicone ball head probe 31 and threadedly connected to the force sensor 33; a flange hole 35 is provided on the upper surface of the force sensor 33 for connecting the multi-axis motion module 2; the central control unit 6 controls the flexible silicone ball head probe 31 to press down to the sensor array of the film under test until the preset target pressure value is reached, and the force sensor 33 collects the pressure signal.

[0009] Preferably, the adaptive fixing module 4 includes a base 41; above the base 41 are alternately stacked electrodes 42 that generate electrostatic adsorption force and an intermediate silicone layer 44; the uppermost layer of the adaptive fixing module 4 is a silicone layer 43 for placing the thin film sensor array under test; the central control unit 6 forms a controllable electrostatic adsorption force to fix the thin film sensor array under test according to the size and shape of the thin film sensor array under test.

[0010] As a preferred embodiment, during the pressure holding phase, the steady-state prediction submodule collects the curve of the pressure signal changing over time, uses an exponential decay model to fit the signal trend, and predicts the steady-state value; when the prediction error is less than a set threshold, it is determined that steady state has been reached.

[0011] Preferably, in the steady-state prediction submodule, a sampling time window T is set, and the signal change rate ΔV / Δt within the window is calculated. If the change rate of N consecutive time windows is less than the creep rate threshold, the prediction is considered successful. Alternatively, through the exponential model V(t) = AB·e -kt If the residual error after fitting is less than the allowable range, it is determined to be in steady state; where Vt refers to the signal value acquired by the sensor, A refers to the final stable value of the signal that eventually tends to stabilize, B refers to the difference between the initial value and the steady state value of the signal, k is the exponential decay rate constant, and e is the Euler constant.

[0012] Preferably, the hysteresis compensation submodule introduces correction terms related to the properties of the thin film material. Based on the hysteresis curve of the thin film material measured in advance, a correction coefficient table related to the properties of the thin film material is generated in advance. During testing, the correction coefficient table is called for real-time compensation. The correction terms related to the properties of the thin film material include the thickness correction, hardness correction and strain rate correction of the sensor.

[0013] Preferably, the central control unit 6 also includes a temperature drift compensation submodule, which is used to combine ambient temperature sensor data and correct the pressure signal by lookup table method or polynomial fitting.

[0014] Secondly, an automatic detection system method for a thin-film pressure sensing array includes the following steps: S1. Place the thin film sensor array to be tested on the adaptive fixing module and start electrostatic adsorption for fixing; S2. Use the visual positioning module to capture images of the thin-film sensor array under test, identify the preset reference marks, and calculate the deviation between the actual position and the rotation angle of the thin-film sensor array under test. S3. The central control unit generates corrected motion trajectory coordinates based on the deviation value; S4. The multi-axis motion module drives the standard pressure detection unit to move above the first test point; controls the Z-axis of the multi-axis motion module to move downward, reads the force sensor value of the standard pressure detection unit in real time, and immediately stops moving downward and enters the pressure holding state when the value reaches the preset target pressure; in the pressure holding state, the output signal of the thin film sensor under test is collected, and the steady-state prediction algorithm is executed at the same time. If it is determined that the steady state has been reached, the data is recorded and the test at that point is ended. S5. Repeat S4 until all preset test points have been tested. S6. The central control unit uses the hysteresis compensation module to correct the output signal and generate the final test report; The automatic detection system method for a thin-film pressure sensor array is applied to an automatic detection system for a thin-film pressure sensor array as described in the first aspect.

[0015] Compared with the prior art, the beneficial effects of the present invention are reflected in: The innovation of this patent lies in the "transformation of control strategy" and the "specific adaptation design for thin film materials, transforming traditional "position control" into "force feedback closed-loop control." Unlike existing electronic testing equipment, which generally employs position control—where the probe is programmed to move to a preset Z-axis height position and then performs a pressing action—this control strategy suffers from the drawback of assuming all tested samples have perfectly uniform thickness. However, actual thin film sensor arrays suffer from uneven thickness, surface irregularities, and film warping. Furthermore, the data collected by the sensor does not strictly correspond to the pressing stroke, resulting in coarse and highly fluctuating data. This invention uses a ball-head sensor combined with hysteresis and creep compensation algorithms to transform "position control" into "force feedback closed-loop control," achieving adaptation to the characteristics of thin film materials.

[0016] This invention employs visual automatic alignment instead of manual adjustment, and its electrostatic adsorption exhibits strong adaptability, significantly improving loading / unloading and testing efficiency. Secondly, force feedback closed-loop control eliminates errors caused by uneven sample thickness, ensuring strictly consistent testing pressure at all points. Thirdly, the flexible probe and constant force control prevent mechanical damage to the thin-film sensor caused by rigid contact. Furthermore, professional hysteresis and creep compensation algorithms, combined with steady-state prediction technology, significantly shorten the single-point testing cycle while maintaining accuracy. Finally, the system architecture of this invention supports switching between single-point scanning and parallel array module testing modes, flexibly handling sensor arrays of different densities and sizes. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the system structure of Embodiment 1 of the present invention; Figure 2 This is a schematic diagram of the structure of the standard pressure detection unit in Embodiment 1 of the present invention; Figure 3 This is a cross-sectional view of the adaptive fixing module according to Embodiment 1 of the present invention; Figure 4 This is a schematic diagram illustrating the principle of visual positioning and motion trajectory correction in Embodiment 1 of the present invention; Figure 5 This is a flowchart of the force feedback closed-loop control logic of Embodiment 1 of the present invention; Figure 6 This is a flowchart of the steady-state prediction algorithm based on the creep model in Embodiment 1 of the present invention; Figure 7 This is a flowchart of the detection method in Embodiment 3 of the present invention.

[0018] The components include: 1. Frame; 2. Multi-axis motion module; 3. Standard pressure detection unit; 4. Adaptive fixing module; 5. Vision positioning module; 6. Central control unit; 31. Flexible silicone ball head probe; 32. Rigid force transmission core; 33. Force sensor; 34. Threaded hole; 35. Flange hole; 41. Base; 42. Electrode; 43. Silicone layer; 44. Intermediate silicone layer. Detailed Implementation

[0019] To make the technical means, inventive features, objectives, and effects of the invention readily understandable, the invention is further described below with reference to specific illustrations. However, the invention is not limited to the embodiments described below.

[0020] It should be noted that the structures, proportions, sizes, etc., illustrated in the accompanying drawings of this specification are only used to complement the content disclosed in the specification for those skilled in the art to understand and read, and are not intended to limit the conditions under which the present invention can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and objectives that the present invention can produce, should still fall within the scope of the technical content disclosed in the present invention.

[0021] Example 1: like Figure 1 An automated detection system for a thin-film pressure sensor array, as shown, includes: Frame 1 serves as the main support structure for the system; Multi-axis motion module 2, mounted on frame 1, is used to provide precision displacement; The standard pressure detection unit 3 is installed at the end of the multi-axis motion module 2 and is used to apply standard pressure to the thin film sensor array under test and collect reference data. The adaptive fixing module 4 is mounted on the frame 1 and located below the standard pressure detection unit 3. It is used to fix the thin film sensor array under test by a controllable electrostatic adsorption force. The visual positioning module 5, mounted on the frame 1, is used to automatically identify the reference marks on the sensor array of the thin film under test and calculate its positional deviation. The central control unit 6 is communicatively connected to the multi-axis motion module 2, the standard pressure detection unit 3, the adaptive fixing module 4, and the visual positioning module 5, respectively. The central control unit 6 is configured as follows: Based on the positional deviation identified by the visual positioning module 5, the motion trajectory of the multi-axis motion module 2 is corrected. The control multi-axis motion module 2 drives the standard pressure detection unit 3 to move to the target test point and executes force feedback closed-loop control so that the standard pressure detection unit 3 contacts the sensitive unit of the thin film sensor array under test with a preset target pressure value; During the pressure holding stage, the output signal of the thin film sensor under test is collected, and the steady-state value is calculated before the physical steady state is reached based on the built-in steady-state prediction algorithm, so as to shorten the single-point test time.

[0022] Specifically, in this embodiment: The frame 1 is constructed using aluminum profiles.

[0023] The multi-axis motion module 2 provides precise displacement in at least three degrees of freedom. It utilizes a high-precision linear motor-driven XYZ three-axis platform with a repeatability accuracy of ±0.01mm. The multi-axis motion module supports two operating modes: single-point scanning mode, which controls the standard pressure detection unit 3 to move point by point to the center of each sensitive unit in the array for testing; and parallel array mode, which, when the standard pressure detection unit 3 is replaced with a miniaturized standard sensor array module, controls it to move to several preset coverage areas, completing parallel testing of multiple sensitive units at once.

[0024] like Figure 2 The standard pressure detection unit 3 shown is equipped with a flexible silicone ball-head probe and a high-response miniature force sensor. The ball-head portion, which directly contacts the membrane under test, is a silicone sphere 31 with an R3-R5mm diameter. The outer layer is a flexible silicone coating, using silicone with a Shore hardness of 30-50. The internal insert is a rigid force transmission core 32 made of aluminum alloy, completely embedded in the center of the silicone ball-head. The tail of the transmission core is a cylindrical connecting rod that extends beyond the silicone ball, with a threaded hole on the end face for connection to the miniature force sensor. The probe and force sensor 33 are rigidly connected by threads. The cylindrical aluminum alloy tail section inside the probe rotates into the corresponding threaded hole 34 of the sensor. The force sensor is cylindrical in shape, with a threaded hole on the lower surface for connecting the probe's connecting post, and a flange hole 35 on the upper surface for connection and fastening with the multi-axis motion module. A Z-axis force feedback closed-loop control strategy is adopted. The system no longer controls the probe to move to a fixed height, but instead controls it to press down until it reaches the preset target pressure value (such as 1N, 5N, etc.), ensuring that the contact conditions are consistent for each test and simulating real working conditions, while protecting the thin film from damage. It is used to apply standard pressure to the thin film sensor array under test and collect reference data.

[0025] like Figure 3The adaptive fixing module 4 shown includes a base 41, electrodes 42 that generate electrostatic adsorption force, and a silicone layer 43 for placing the test piece on its surface, with an intermediate silicone layer 44 as a separator. The central control unit 6 generates a controllable electrostatic adsorption force to fix the test piece according to its size and shape. The base surface of the adaptive fixing module is made of silicone. When a thin-film sensor is placed inside, the control system activates the electrodes below to form a stable electrostatic adsorption.

[0026] Visual positioning module 5: Integrates an industrial camera, which automatically captures the reference marks on the workpiece under test through image recognition algorithms, calculates the coordinate offset and rotation angle, and feeds it back to the central control unit 6 to correct the motion trajectory, achieving fully automatic high-precision alignment. The visual positioning module uses a 5-megapixel industrial camera with a telecentric lens, mounted on the side of the Z-axis, and takes pictures through a reflector or by directly looking down.

[0027] like Figure 4 As shown, in the visual positioning module, the software preprocesses the image, extracts the center coordinates of the circular markers at the four corners of the film under test, calculates the translation (Δx, Δy) and rotation angle θ using the least squares method, and superimposes these parameters into a preset test point coordinate matrix. The central control unit 6 (circuit module, installed and fixed in rack 1) incorporates advanced data processing algorithms, including an exponential model-based creep steady-state prediction algorithm (which can calculate the final value without waiting for complete physical steady-state, significantly shortening test time), a polynomial fitting hysteresis compensation algorithm, and a temperature drift compensation algorithm. The central control unit 6 embeds a data processing algorithm module, which includes: like Figure 6 As shown, the steady-state prediction algorithm submodule based on the creep model: Due to the slippage of the thin film material, a phenomenon occurs where a force sensor applies a constant force to the thin film sensor and still obtains a continuous strain reading. To address this, a steady-state prediction algorithm based on the creep model is proposed. During the pressure holding stage, the curve of the pressure signal changing with time is collected to determine whether the stress boundary has been reached. The creep constitutive model, such as the exponential decay model, is used to fit the signal trend and predict the steady-state value. When the prediction error is less than a set threshold, it is determined that the steady state has been reached, thereby shortening the test waiting time. Set a sampling time window T, calculate the signal change rate ΔV / Δt within the window, and if the change rate of N consecutive time windows is less than the creep rate threshold... (To determine the critical value of the steady-state rate of change, a small positive number is usually chosen), or it can be determined using the exponential model V(t) = AB·e -kt (Vt refers to the signal value acquired by the sensor, A refers to the final stable value of the signal, B refers to the difference between the initial value and the steady-state value of the signal, k is the exponential decay rate constant, and e is the Euler constant.) If the residual error after fitting is less than the allowable range, it is determined to be in steady state.

[0028] The hysteresis compensation submodule records data during the loading and unloading processes, constructs a hysteresis loop mathematical model, and performs real-time nonlinear compensation on the test data. The hysteresis loop model is a mature existing technology, and hysteresis compensation technology has been successfully applied in piezoelectric sensors and actuators. However, this design aims to create a dedicated testing system for thin-film sensors. First, the hysteresis compensation algorithm participates in the motion control of the system hardware, guiding force control to achieve the compensation effect. Second, the algorithm in this system requires targeted improvements, introducing correction terms related to the characteristics of the thin-film material. During testing, even when the same pressure is applied, the output signal of the thin-film sensor varies. This phenomenon is caused by the elastic hysteresis of the thin-film material and its smooth surface characteristics. This algorithm incorporates thickness, hardness, and strain rate corrections for the sensor. Based on the pre-measured hysteresis curve of the thin-film material, a correction coefficient table related to the relevant characteristics of the thin-film material is pre-generated and called for real-time compensation during testing, forming a compensation scheme with unique technical features.

[0029] Temperature drift compensation submodule: Combines ambient temperature sensor data to correct pressure readings using lookup table method or polynomial fitting.

[0030] The system also includes a host computer interface for displaying real-time test progress, pressure distribution heatmap, single test waveform curves, and abnormal alarm information.

[0031] like Figure 5 As shown, in this embodiment, the Z-axis of the multi-axis motion module approaches the sample surface at a speed of 5 mm / s during the rapid descent phase. During contact detection, the standard pressure detection unit determines contact when the force sensor reading exceeds the 0.05 N threshold. Constant force loading: The standard pressure detection unit 3 switches to PID force control mode, pressing down at a fine-tuning speed of 0.1 mm / s until the reading stabilizes at the target value (e.g., 2.0 N ± 0.02 N). The pressure is maintained, and the signal from the test piece is acquired at a frequency of 100 Hz. Data for the first 2 seconds is acquired, and the fitting formula V(t) = V final -A·e -t / τ (Vt refers to the signal value acquired by the sensor, V) final V represents the final stable value to which the signal eventually tends to stabilize. A is the difference between the initial value and the steady-state value. τ is the exponentially decaying time constant, representing the time required for the signal to reach approximately 63.2% of its final value. e is Euler's constant. If the fitting residual is less than the set value, V is output directly. final As a test result, there is no need to wait for the traditional physical settling time of more than 10 seconds. After the test is completed, a pre-calibrated hysteresis compensation coefficient table is called to correct the original data and output the final linearized data.

[0032] Example 2: An automatic detection system method for a thin-film pressure sensing array includes the following steps: S1. Place the thin film sensor array to be tested on the adaptive fixing module and start electrostatic adsorption for fixing; S2. Use the visual positioning module to capture images of the thin-film sensor array under test, identify the preset reference marks, and calculate the deviation between the actual position and the rotation angle of the thin-film sensor array under test. S3. The central control unit generates corrected motion trajectory coordinates based on the deviation value; S4. The multi-axis motion module drives the standard pressure detection unit to move above the first test point; controls the Z-axis of the multi-axis motion module to move downward, reads the force sensor value of the standard pressure detection unit in real time, and immediately stops moving downward and enters the pressure holding state when the value reaches the preset target pressure; in the pressure holding state, the output signal of the thin film sensor under test is collected, and the steady-state prediction algorithm is executed at the same time. If it is determined that the steady state has been reached, the data is recorded and the test at that point is ended. S5. Repeat S4 until all preset test points have been tested. S6. The central control unit uses a hysteresis compensation module to correct the output signal and generate a final test report. The central control unit runs customized software on an industrial computer.

[0033] Example 3: Workflow as follows Figure 7 As shown, the operator places the thin-film sensor array on the base, clicks "Start Test", and the system automatically starts electrostatic adsorption, the camera takes pictures and aligns the sensor, the robotic arm moves along the corrected trajectory, and performs force-controlled pressing tests point by point, generating a pressure distribution heat map in real time. When the test is completed, the electrostatic discharge is activated, and an audible and visual prompt is given to remove the test piece.

[0034] Through the above implementation methods, this system successfully solves the pain points of traditional detection devices and achieves the goal of high-quality automated detection of thin-film sensor arrays.

Claims

1. An automatic detection system for a thin-film pressure sensor array, characterized in that, include: The frame (1) serves as the main support structure for the system; A multi-axis motion module (2) is mounted on the frame (1) and is used to provide displacement; The standard pressure detection unit (3) is installed at the end of the motion of the multi-axis motion module (2) and is used to apply standard pressure to the thin film sensor array under test. An adaptive fixing module (4) is mounted on the frame (1) and located below the standard pressure detection unit (3) for fixing the thin film sensor array to be tested; The visual positioning module (5) is mounted on the frame (1) and is used to automatically identify the reference marks on the thin film sensor array under test and calculate the position deviation; The central control unit (6) is communicatively connected to the multi-axis motion module (2), the standard pressure detection unit (3), the adaptive fixation module (4), and the vision positioning module (5), respectively; the central control unit (6) is configured as follows: Based on the positional deviation, the motion trajectory of the multi-axis motion module (2) is corrected; the multi-axis motion module (2) is controlled to drive the standard pressure detection unit (3) to move to the target test point, and force feedback closed-loop control is executed so that the standard pressure detection unit (3) contacts the sensitive unit of the thin film sensor array under test with a preset target pressure value; During the pressure holding stage, the output signal of the thin film sensor under test is acquired. Based on the built-in steady-state prediction submodule, the steady-state value is predicted before the physical steady state is reached, and the steady-state value is corrected in real time based on the built-in hysteresis compensation submodule.

2. The automatic detection system for a thin-film pressure sensor array according to claim 1, characterized in that, The multi-axis motion module (2) supports two working modes, namely: In single-point scanning mode, the standard pressure detection unit (3) is controlled to move point by point to the center of each sensitive unit on the thin film sensor array under test for testing; in parallel array mode, the standard pressure detection unit (3) is a miniaturized standard sensor array module, and the miniaturized standard sensor array module is controlled to move to several preset coverage areas to complete the parallel testing of multiple sensitive units at one time.

3. The automatic detection system for a thin-film pressure sensor array according to claim 1, characterized in that, The standard pressure detection unit (3) includes a force sensor (33) and a flexible silicone ball head probe (31) for direct contact with the film to be tested; a rigid force transmission core (32) is embedded in the center of the flexible silicone ball head probe (31); a cylindrical connecting rod is provided at the tail of the transmission core, extending out of the flexible silicone ball head probe (31) and threadedly connected to the force sensor (33); a flange hole (35) is provided on the upper surface of the force sensor (33) for connecting the multi-axis motion module (2); the central control unit (6) controls the flexible silicone ball head probe (31) to press down to the sensor array of the film to be tested until the preset target pressure value is reached, and the force sensor (33) collects the pressure signal.

4. The automatic detection system for a thin-film pressure sensor array according to claim 1, characterized in that, The adaptive fixing module (4) includes a base (41); the base (41) is provided with alternatingly stacked electrodes (42) that generate electrostatic adsorption force and an intermediate layer of silicone (44); the uppermost layer of the adaptive fixing module (4) is provided with a silicone layer (43) for placing the thin film sensor array under test; the central control unit (6) forms a controllable electrostatic adsorption force to fix the thin film sensor array under test according to the size and shape of the thin film sensor array under test.

5. The automatic detection system for a thin-film pressure sensor array according to claim 1, characterized in that, During the pressure holding phase, the steady-state prediction submodule collects the curve of pressure signal changing over time, uses an exponential decay model to fit the signal trend, and predicts the steady-state value; when the prediction error is less than a set threshold, it is determined that steady state has been reached.

6. The automatic detection system for a thin-film pressure sensor array according to claim 5, characterized in that, In the steady-state prediction submodule, a sampling time window T is set, and the rate of change of the signal within the window ΔV / Δt is calculated. If the rate of change of the signal for N consecutive time windows is less than the creep rate threshold, the prediction is successful. Alternatively, through the exponential model V(t) = AB·e -kt If the residual error after fitting is less than the allowable range, it is determined to be in steady state; where Vt refers to the signal value acquired by the sensor, A refers to the final stable value of the signal that eventually tends to stabilize, B refers to the difference between the initial value and the steady state value of the signal, k is the exponential decay rate constant, and e is the Euler constant.

7. The automatic detection system for a thin-film pressure sensor array according to claim 1, characterized in that, The hysteresis compensation submodule introduces correction terms related to the properties of thin film materials. Based on the hysteresis curves of the thin film materials measured in advance, a table of correction coefficients related to the properties of the thin film materials is generated in advance. During testing, the correction factor table is called for real-time compensation; correction items related to thin film material properties include sensor thickness correction, hardness correction, and strain rate correction.

8. The automatic detection system for a thin-film pressure sensor array according to claim 1, characterized in that, The central control unit (6) also includes a temperature drift compensation submodule, which combines ambient temperature sensor data to correct the pressure signal by lookup table method or polynomial fitting.

9. An automatic detection method for a thin-film pressure sensing array, characterized in that, Includes the following steps: S1. Place the thin film sensor array to be tested on the adaptive fixing module and start electrostatic adsorption for fixing; S2. Use the visual positioning module to capture images of the thin-film sensor array under test, identify the preset reference marks, and calculate the deviation between the actual position and the rotation angle of the thin-film sensor array under test. S3. The central control unit generates corrected motion trajectory coordinates based on the deviation value; S4. The multi-axis motion module drives the standard pressure detection unit to move above the first test point; controls the Z-axis of the multi-axis motion module to move downward, reads the force sensor value of the standard pressure detection unit in real time, and immediately stops moving downward and enters the pressure holding state when the value reaches the preset target pressure; in the pressure holding state, the output signal of the thin film sensor under test is collected, and the steady-state prediction algorithm is executed at the same time. If it is determined that the steady state has been reached, the data is recorded and the test at that point is ended. S5. Repeat S4 until all preset test points have been tested. S6. The central control unit uses the hysteresis compensation module to correct the output signal and generate the final test report; The automatic detection method for a thin-film pressure sensor array is applied to the automatic detection system for a thin-film pressure sensor array as described in claim 1.

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