A method and system for detecting the performance of a new membrane material

Abstract

The application provides a performance detection method and system of a new type of membrane material, and relates to the technical field of membrane material detection. The application applies uniform pressure load to a membrane material sample by using a gas pressure loading mode, so that the sample generates off-plane deformation. Compared with a traditional mechanical tensile loading mode, the application more truly simulates the stress state of the membrane material in practical application scenarios such as an air-filled membrane structure and an air-supported roof. The measured mechanical parameters such as the elastic modulus and the breaking strength have higher guiding value for engineering practice. During the execution of the mechanical performance detection, the application synchronously performs optical performance detection, realizes in-situ real-time measurement of optical parameters such as the light transmittance, the haze and the surface defects of the membrane material under the action of the load, can establish a dynamic corresponding relationship between the mechanical deformation and the optical performance attenuation, and overcomes the problem of missing related data caused by the separation of the mechanical test and the optical test in the traditional method.

Description

Technical Field

[0001] This invention relates to the field of membrane material testing technology, and more specifically, to a novel method and system for testing the performance of membrane materials. Background Technology

[0002] Membrane materials, as a new type of high-performance material, have been widely used in building curtain walls, inflatable membrane structures, waterproofing projects, electronic device packaging, and separation membranes. The mechanical properties and physical durability of membrane materials directly affect their service life and safety; therefore, accurate performance testing is crucial. Currently, membrane material performance testing mainly faces the following technical challenges: Existing testing methods mostly employ uniaxial or biaxial mechanical tensile testing to obtain parameters such as elastic modulus and tensile strength. However, in practical applications, such as inflatable membrane structures and air-supported roofs, membrane materials primarily bear uniformly distributed air pressure loads. Their stress mode is out-of-plane deformation caused by out-of-plane uniform pressure, which is fundamentally different from the in-plane stress mode under mechanical tensile loading. The mechanical parameters obtained using traditional tensile tests are insufficient to accurately reflect the mechanical response behavior of membrane materials under real uniformly distributed pressure conditions. Therefore, we propose an improvement, namely a novel membrane material performance testing method and system. Summary of the Invention

[0003] This invention provides a novel method for testing the performance of membrane materials, comprising the following steps: Obtain a sample of the membrane material to be tested, place the sample in a closed testing environment and keep it under tension; set the environmental parameters of the closed testing environment, including at least one of temperature, humidity and irradiation parameters. A uniform pressure load is applied to the sample by air pressure loading to induce out-of-surface deformation of the sample. During the loading process, load data and sample deformation data are collected synchronously at a predetermined sampling frequency. Based on the collected load and deformation data, the mechanical property parameters of the sample are calculated, including elastic modulus and fracture strength. During the mechanical property testing, the physical property parameters of the sample are obtained through optical detection methods. The physical property parameters include at least one of transmittance, haze, and surface defect parameters. By performing correlation analysis between mechanical and physical performance parameters, a comprehensive performance evaluation result of the sample is generated.

[0004] As a preferred technical solution of this application, the pneumatic loading method includes static pneumatic loading mode and dynamic pneumatic loading mode; In static air pressure loading mode, the gas pressure in the sealed detection environment is controlled to continuously increase to the target pressure value at a predetermined rate. In dynamic air pressure loading mode, the gas pressure in the sealed detection environment is controlled to change periodically according to a preset waveform, which includes at least one of sine wave, square wave and triangle wave.

[0005] As a preferred technical solution of this application, the sample deformation data is acquired through a non-contact optical measurement method, including: continuously acquiring image sequences of the sample surface; performing sub-pixel-level edge localization processing on each frame of the image sequence to extract the current edge contour of the sample; and calculating the out-of-plane displacement field and in-plane strain field of the sample during the loading process based on the offset of the current edge contour relative to the initial edge contour.

[0006] As a preferred technical solution of this application, it also includes online crack recognition: performing illumination equalization and noise filtering preprocessing on the current image in the image sequence; performing gradient operator-based edge detection on the preprocessed image to extract the crack edges present on the sample surface; calculating crack parameters based on the geometric features of the crack edges, the crack parameters including at least one of crack length, crack width, crack area and crack propagation rate; and generating a crack warning signal when the crack length or crack width exceeds a preset warning threshold.

[0007] As a preferred technical solution of this application, when uniform pressure is applied, the elastic modulus is calculated based on the functional relationship between the uniform pressure value and the displacement value of the center point of the sample.

[0008] As a preferred technical solution of this application, the optical detection methods include transmittance detection and surface defect detection; Transmittance detection includes: vertically irradiating the sample surface with incident light, collecting the transmitted light that passes through the sample, measuring the light intensity of the transmitted light at different wavelengths, and calculating the spectral transmittance curve based on the ratio of the incident light intensity to the transmitted light intensity. Surface defect detection includes: acquiring high-resolution grayscale images of the sample surface, extracting defect regions from the grayscale images using a threshold-based segmentation algorithm, and statistically analyzing the number, area, and location distribution of defect regions.

[0009] As a preferred technical solution of this application, the irradiation parameters are controlled as follows: the output power of the irradiation source is adjusted by pulse width modulation according to the preset irradiation intensity setting value so that the irradiation intensity is maintained at the set value; during the irradiation process, the temperature value of the sample surface is collected at preset time intervals, and when the temperature value exceeds the preset temperature threshold, the output power of the irradiation source is reduced or irradiation is paused.

[0010] As a preferred technical solution of this application, the method for generating the comprehensive performance evaluation result includes: comparing the mechanical performance parameters and physical performance parameters with the corresponding standard thresholds to obtain the rating result of each individual parameter; calculating the comprehensive score by weighting and summing the rating results of each individual parameter according to the preset weighting coefficients; and determining the quality grade of the sample based on the comprehensive score.

[0011] A novel performance testing system for membrane materials includes: Environmental control unit, used to adjust the environmental parameters of the sealed detection environment; The pneumatic loading control unit is used to apply a uniform pressure load to the membrane material sample installed in the closed detection environment by controlling the gas pressure change in the closed detection environment. The data synchronization acquisition unit is used to simultaneously acquire load data and sample deformation data during the air pressure loading process; The mechanical property calculation unit is used to calculate the mechanical property parameters of the sample based on the collected load data and deformation data. The mechanical property parameters include elastic modulus and fracture strength. An optical performance testing unit is used to acquire physical performance parameters of a sample through optical detection during or between mechanical performance testing operations. The physical performance parameters include at least one of transmittance, haze, and surface defect parameters. The comprehensive evaluation unit is used to perform correlation analysis between mechanical and physical performance parameters to generate comprehensive performance evaluation results for the sample.

[0012] As a preferred technical solution of this application, the pneumatic loading control unit includes a static loading control subunit and a dynamic loading control subunit; The static loading control subunit is used to continuously increase the gas pressure in the sealed detection environment to the target pressure value at a predetermined rate using a closed-loop control method. The dynamic loading control subunit is used to make the gas pressure in the closed detection environment change periodically according to a preset waveform.

[0013] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This application uses pneumatic loading to apply a uniformly distributed pressure load to the membrane material sample, causing the sample to undergo out-of-plane deformation. Compared with the traditional mechanical tensile loading method, it more realistically simulates the stress state of the membrane material in actual application scenarios such as inflatable membrane structures and air-supported roofs. The measured mechanical parameters such as elastic modulus and fracture strength have higher guiding value for engineering practice. 2. During the mechanical performance testing, the present invention simultaneously performs optical performance testing, realizing in-situ real-time measurement of optical parameters such as transmittance, haze, and surface defects of the film material under load. It can establish a dynamic correspondence between mechanical deformation and optical performance attenuation, overcoming the problem of missing correlation data caused by the separation of mechanical testing and optical testing in traditional methods. 3. This invention allows for mechanical testing of membrane material samples under controlled environmental conditions by setting temperature, humidity, and irradiation parameters during or before air pressure loading. This enables the membrane material to reflect its performance degradation under the coupled effects of temperature, humidity, and ultraviolet irradiation in real time during the mechanical loading process. Attached Figure Description

[0014] Figure 1 A flowchart of the performance testing method for the novel membrane material provided in this application; Figure 2 Flowchart for obtaining sample deformation data provided in this application; Figure 3 The flowchart for online crack identification provided in this application; Figure 4 The transmittance testing flowchart provided for this application; Figure 5 A flowchart for surface defect detection provided for this application. Detailed Implementation

[0015] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0016] It should be noted that, unless otherwise specified, the embodiments and features and technical solutions in the present invention can be combined with each other.

[0017] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0018] Example 1, please refer to Figure 1-5 A novel method for testing the performance of membrane materials includes the following steps: Obtain a sample of the membrane material to be tested, place the sample in a closed testing environment and keep it under tension; set the environmental parameters of the closed testing environment, including at least one of temperature, humidity and irradiation parameters. A uniform pressure load is applied to the sample by air pressure loading to induce out-of-surface deformation of the sample. During the loading process, load data and sample deformation data are collected synchronously at a predetermined sampling frequency. Based on the collected load and deformation data, the mechanical property parameters of the sample are calculated, including elastic modulus and fracture strength. During the mechanical property testing, the physical property parameters of the sample are obtained through optical detection methods. The physical property parameters include at least one of transmittance, haze, and surface defect parameters. By performing correlation analysis between mechanical and physical performance parameters, a comprehensive performance evaluation result of the sample is generated. Specifically, the operator first cuts a sample of the novel membrane material to be tested and installs it on the sample clamping station of the sealed testing chamber. A uniform tension force is applied to the sample edges using the existing tensioning mechanism to maintain a flat tension state during the testing process, preventing wrinkles from affecting testing accuracy. After the sample is installed, the sealed testing chamber is closed, and environmental parameters such as temperature, humidity, and irradiance are adjusted to preset target values, for example, a temperature of 65℃, relative humidity of 85%, and irradiance of 800W / m². Once the environmental parameters stabilize, compressed gas is introduced into the sealed chamber, creating a pressure difference between the upper and lower surfaces of the sample. Under the uniform pressure, the sample undergoes out-of-surface bulging deformation. Throughout the entire process of gas pressure loading… During the process, the data acquisition system synchronously acquires the gas pressure value (i.e., load data) in the cavity and the deformation data of the sample surface at a preset sampling frequency (e.g., 100Hz). The deformation data can be obtained by strain gauges installed on the sample surface or by a non-contact optical measurement system. After the acquisition is completed, the mechanical performance parameters such as the elastic modulus and fracture strength of the sample are calculated based on the pressure-deformation relationship curve. At the same time, during the mechanical performance testing process, an optical detection device is used to perform transmittance testing and surface scanning imaging on the sample through the transparent window of the sealed cavity to obtain the transmittance, haze value, and information on whether there are defects such as bubbles, scratches, and impurities on the surface. Finally, a comprehensive performance evaluation report of the membrane material sample is generated.

[0019] Furthermore, the pneumatic loading methods include static pneumatic loading mode and dynamic pneumatic loading mode; In static pneumatic loading mode, the gas pressure in the sealed testing environment is continuously increased to the target pressure value at a predetermined rate. Specifically, in static pneumatic loading mode, the opening of the inlet valve and the exhaust valve are controlled by closed-loop PID regulation, so that the gas pressure in the sealed testing environment increases continuously and smoothly from zero at a set rate (e.g., 0.5 kPa / s) until the preset target pressure value (e.g., 50 kPa) is reached. During the pressurization process, the pressure value and the corresponding sample deformation are continuously recorded until the sample breaks and is destroyed, thereby obtaining a complete pressure-deformation curve. In dynamic pneumatic loading mode, the gas pressure in the sealed testing environment is controlled to change periodically according to a preset waveform, which includes at least one of sine wave, square wave, and triangular wave. In dynamic pneumatic loading mode, control commands are generated according to the preset pressure-time waveform function, and the chamber pressure is adjusted in real time through a servo proportional valve so that the gas pressure changes periodically according to the set waveform. For example, it can change cyclically between 10 kPa and 40 kPa in the form of a sine wave with a cycle period of 60 seconds, or switch stepwise between high and low pressure values ​​in the form of a square wave, or perform linear rise and fall cycles in the form of a triangular wave. The dynamic pneumatic loading mode is used to simulate the alternating load conditions such as wind pressure pulsation and vibration that the membrane material is subjected to in actual service, so as to evaluate the fatigue performance and durability of the membrane material under dynamic load. Apply sinusoidal pressure. The preset pressure-time waveform function is: P(t)=A*sin(2πft)+P0, where A is the amplitude, f is the frequency, P0 is the pressure bias, and t is the time.

[0020] To apply linearly increasing pressure, the preset pressure-time waveform function is: P(t) = k*t + P1, where k is the pressure increase rate, P1 is the initial pressure, and t is the time.

[0021] Furthermore, sample deformation data is acquired through non-contact optical measurement, including: continuously acquiring image sequences of the sample surface; performing sub-pixel-level edge localization processing on each frame of the image sequence to extract the current edge contour of the sample; and calculating the out-of-plane displacement field and in-plane strain field of the sample during loading based on the offset of the current edge contour relative to the initial edge contour. Specifically, an artificial speckle pattern is prepared on the sample surface, for example, by spraying matte white paint and then randomly scattering black paint dots to form high-contrast speckle. A high-speed industrial camera is fixed outside the transparent observation window of the sealed cavity, ensuring that the optical axis is perpendicular to the sample surface. During the air pressure loading process, the camera continuously acquires a speckle image sequence of the sample surface at a predetermined frame rate (e.g., 50 frames / second). For each frame acquired... The image processing unit first executes a sub-pixel-level edge localization algorithm, specifically a sub-pixel edge detection method based on gray-scale moments, to accurately fit the gray-scale gradient changes in the sample edge region, improving the edge localization accuracy to the 0.1 pixel level. Then, it extracts the complete edge contour of the sample in the current frame image, using the initial edge contour before loading as a reference. By comparing the spatial position offset of the same feature point between the current edge contour and the initial edge contour, and combining the camera calibration parameters, the out-of-plane displacement value of each point on the sample surface under pressure can be calculated. Then, the strain field distribution in the surface, including radial strain and circumferential strain, is obtained by differentiating the displacement field with respect to the spatial coordinates, providing a comprehensive deformation data foundation for subsequent mechanical parameter calculations.

[0022] Furthermore, it also includes online crack identification: performing illumination equalization and noise filtering preprocessing on the current image in the image sequence; performing gradient operator-based edge detection on the preprocessed image to extract crack edges present on the sample surface; calculating crack parameters based on the geometric features of the crack edges, including at least one of crack length, crack width, crack area, and crack propagation rate; generating a crack warning signal when the crack length or crack width exceeds a preset warning threshold; specifically, acquiring sample surface images captured by a camera, performing illumination equalization processing on the current image, using a histogram equalization algorithm to adjust the image grayscale distribution to eliminate the influence of uneven ambient lighting, and then using median filtering or Gaussian filtering for noise filtering to suppress random noise introduced during image acquisition; After preprocessing, an edge detection algorithm based on the Canny operator is used to extract all possible crack edges in the image. This algorithm accurately extracts the complete boundary of the crack region by calculating the image gradient magnitude and direction, non-maximum suppression, and double threshold hysteresis connection. After extracting the crack edge, calculate the geometric feature parameters of the crack: the crack length is the Euclidean distance between the two ends of the crack, the crack width is the average vertical distance between the two sides of the crack edge, and the crack area is the total number of pixels in the crack closed area multiplied by the pixel equivalent area. Based on this, the crack propagation rate, i.e. the increment of crack length per unit time, is calculated by comparing the length change and time interval of the same crack in consecutive frame images. When the crack length exceeds the preset warning threshold (e.g., 5 mm) or the crack width exceeds the warning threshold (e.g., 0.5 mm), a crack warning signal is immediately generated and the operator is notified by sound and light alarm. At the same time, a warning mark is added to the data record at that time point.

[0023] Furthermore, when uniform pressure loading is used, the elastic modulus is calculated based on the functional relationship between the uniform pressure value and the out-of-plane displacement value of the sample's center point. When uniform pressure loading is used, the sample is fixed around the periphery under the clamping of a circular fixture, and the central region undergoes out-of-plane deformation due to the uniform pressure. In this case, the sample can be approximated as a circular thin plate with fixed periphery. Based on the theory of small deflection thin plates, the relationship between the out-of-plane displacement w of the sample's center point and the uniform pressure p satisfies: p=(16E·t³) / (3(1-ν²)R) 4 )·w, where E is the elastic modulus to be determined, t is the sample thickness, ν is Poisson's ratio (obtained from the material handbook or through independent testing), R is the radius of the exposed area of ​​the sample, and w is the displacement value of the center point from the surface; therefore, after obtaining the slope of the linear segment of the pressure-center displacement curve, the elastic modulus of the sample can be calculated by substituting it into the above formula.

[0024] Furthermore, optical inspection methods include transmittance inspection and surface defect inspection; Transmittance detection includes: incident light is perpendicularly irradiated onto the sample surface, the transmitted light passing through the sample is collected, the intensity of the transmitted light at different wavelengths is measured, and the spectral transmittance curve is calculated based on the ratio of the incident light intensity to the transmitted light intensity. Specifically, a standard light source (such as a xenon lamp or halogen tungsten lamp) is set on one side of the sealed cavity. After the light source emits collimated white light, it is processed by a monochromator to obtain monochromatic incident light of a specific wavelength, which is perpendicularly irradiated onto the sample surface. An integrating sphere and a photodetector are set on the other side of the sample. The integrating sphere is used to collect all the transmitted light passing through the sample and eliminate the loss of scattered light. The photodetector converts the optical signal of the transmitted light into an electrical signal and performs analog-to-digital conversion. For each test wavelength point, the incident light intensity I0 and the transmitted light intensity I are recorded respectively. The transmittance value at that wavelength is calculated according to the transmittance T=I / I0×100%. The spectral transmittance curve can be obtained by scanning and measuring in the wavelength range of 300nm to 1100nm. Surface defect detection includes: acquiring high-resolution grayscale images of the sample surface; extracting defect regions from the grayscale images using a threshold-based segmentation algorithm; and statistically analyzing the number, area, and location distribution of defect regions. A high-resolution area array camera is used to acquire grayscale images of the sample surface under uniform illumination. After Gaussian filtering and smoothing, the Otsu adaptive threshold segmentation algorithm is used to separate defect regions (typically appearing as areas of abrupt grayscale changes) from normal regions. Then, a connected component labeling algorithm is used to statistically analyze the number of pixels and location coordinates of each defect region. Combined with calibration parameters, the pixel area is converted into a physical area. Finally, the number of defect regions, the physical area of ​​each defect, and a two-dimensional heat map of defect distribution on the sample surface are output.

[0025] Furthermore, the irradiation parameters are controlled as follows: The output power of the irradiation source is adjusted using pulse width modulation (PWM) based on a preset irradiation intensity setting to maintain the irradiation intensity at the set value. During irradiation, the temperature of the sample surface is collected at preset time intervals. When the temperature exceeds a preset temperature threshold, the output power of the irradiation source is reduced or irradiation is paused. An irradiation source (such as a xenon lamp or metal halide lamp) is projected onto the sample surface inside a sealed cavity or through a quartz window. The target irradiation intensity is set by the test standard or the user (e.g., 1000 W / m²). The output power of the irradiation source is adjusted using pulse width modulation (PWM), specifically by outputting a PWM control signal at a fixed frequency (e.g., 1 kHz). The average output power of the irradiation source is changed by adjusting the duty cycle of the PWM signal. An irradiance sensor installed inside the cavity measures the actual irradiation intensity of the sample surface in real time. The controller compares the measured value with the set value and dynamically adjusts the PWM duty cycle using a PID algorithm to stabilize the irradiation intensity within ±5% of the set value. During irradiation, thermocouples attached to the sample surface or infrared temperature sensors inside the cavity collect real-time temperature values ​​of the sample surface at preset time intervals (e.g., once every 10 seconds). The temperature acquisition signals are sent to the safety protection module. When the monitored temperature value exceeds the preset safe temperature threshold (e.g., the heat distortion temperature of the sample material), the PWM duty cycle is reduced to a safe level, or the irradiation source power is turned off directly to pause irradiation. Irradiation is gradually resumed after the sample temperature drops back to a safe range, thereby avoiding unexpected thermal damage to the sample due to overheating caused by irradiation.

[0026] Furthermore, the comprehensive performance evaluation results are generated by comparing mechanical and physical performance parameters with their corresponding standard thresholds to obtain the rating results for each individual parameter; calculating the comprehensive score by weighting and summing the rating results of each individual parameter according to preset weighting coefficients; and determining the quality grade of the sample based on the comprehensive score. Specifically, a standard database is constructed, which presets the standard threshold ranges and corresponding rating levels for each parameter according to different application scenarios. For example, for membrane materials used in construction, the standard thresholds for elastic modulus are: ≥800MPa for Grade A, 600~800MPa for Grade B, and <600MPa for Grade C; tensile strength is ≥50MPa for Grade A, 35~50MPa for Grade B, and <35MPa for Grade C; light transmittance is ≥85% for Grade A, 70~85% for Grade B, and <70% for Grade C; and surface defect density is ≤0.5 defects / m² for Grade A, 0.5~2 defects / m² for Grade B, and >2 defects / m² for Grade C. Each measured parameter is compared with its corresponding standard threshold, and each individual parameter is mapped to a three-level rating result (A / B / C). Then, based on the preset application field of the membrane material, the corresponding weighting coefficient configuration table is called. For example, for membrane materials used in photovoltaic encapsulation, the weighting coefficient for transmittance is set to 0.35, elastic modulus to 0.25, tensile strength to 0.20, haze to 0.15, and surface defects to 0.05; while for membrane materials used in building structures, the weights for elastic modulus and tensile strength are correspondingly increased. Each individual rating result is quantified as A=100 points, B=70 points, and C=40 points, and then weighted and summed with its respective weight to calculate a comprehensive score (out of 100). Finally, the quality grade is determined based on the comprehensive score: a comprehensive score ≥90 points is excellent, 75–90 points is first-class, 60–75 points is qualified, and <60 points is unqualified. A complete test report containing individual ratings, comprehensive scores, and quality grades is generated.

[0027] Example 2: A novel performance testing system for membrane materials, comprising: The environmental control unit is used to adjust the environmental parameters of the sealed detection environment. The environmental parameters include at least one of temperature, humidity and irradiation parameters. The environmental control unit specifically includes a heater (installed on the inner wall of the sealed cavity and heated by electric heating), a humidifier (adjusting humidity by steam injection), a refrigeration compressor (used for cooling and dehumidification), and an irradiation lamp assembly (installed on the top of the cavity). Each environmental control unit is controlled by a central controller and automatically adjusts according to the set temperature, humidity and irradiation parameters. The pneumatic loading control unit is used to apply a uniform pressure load to the membrane material sample installed in the closed detection environment by controlling the gas pressure change in the closed detection environment. The pneumatic loading control unit consists of a high-pressure gas source, a precision pressure reducing valve, an electro-proportional valve, an inlet and outlet solenoid valve, and a pressure sensor installed on the side wall of the cavity. The central controller outputs an analog control signal to the electro-proportional valve according to the set loading curve to achieve precise closed-loop regulation of the gas pressure in the cavity. The data synchronization acquisition unit is used to synchronously acquire load data and sample deformation data during the air pressure loading process. This unit is further subdivided into an image acquisition control subunit, a sensor data acquisition subunit, and an image processing subunit. The image acquisition control subunit includes a camera trigger controller and an image acquisition card. The trigger controller generates a fixed-frequency pulse signal in hardware to trigger camera exposure. The image acquisition card transmits the image data output by the camera to the image processing subunit in real time via the GigE interface. The sensor data acquisition subunit includes a multi-channel synchronous sampling data acquisition card, which simultaneously receives the analog voltage signal from the air pressure sensor and the output signal from the displacement sensor. All channels are driven by the same sampling clock to achieve strict synchronization. The image processing subunit is an industrial control computer equipped with a high-performance GPU, running image processing algorithm software to receive image sequences in real time and perform sub-pixel edge localization and deformation calculation. The mechanical property calculation unit is used to calculate the mechanical property parameters of the sample based on the collected load data and deformation data. The mechanical property parameters include elastic modulus and fracture strength. An optical performance testing unit is used to acquire physical performance parameters of a sample through optical detection during or between mechanical performance testing operations. The physical performance parameters include at least one of transmittance, haze, and surface defect parameters. The comprehensive evaluation unit is used to perform correlation analysis between mechanical and physical performance parameters to generate comprehensive performance evaluation results for the sample.

[0028] Furthermore, the pneumatic loading control unit includes a static loading control subunit and a dynamic loading control subunit; The static loading control subunit is used to continuously increase the gas pressure in the sealed detection environment to the target pressure value at a predetermined rate using closed-loop control. Specifically, the central controller has a built-in PID controller. The PID controller receives the target pressure value and pressure increase rate set by the operator, uses the deviation between the current pressure value and the target value as input, calculates and outputs a control voltage to the electro-proportional valve, and continuously reads the feedback value of the pressure sensor at millisecond intervals for closed-loop correction. This ensures that the pressure in the chamber increases continuously and without overshoot to the target pressure value at a set rate (e.g., 0.2 kPa / s, 0.5 kPa / s, or 1 kPa / s selectable). After reaching the target value, the pressure is maintained at a constant pressure for a preset holding time (e.g., 600 seconds). The dynamic loading control subunit is used to make the gas pressure in the closed testing environment change periodically according to a preset waveform. The preset waveform includes at least one of sine wave, square wave and triangle wave. Specifically, the central controller has a built-in waveform generator. The operator selects the waveform type (sine wave, square wave or triangle wave) and sets parameters such as waveform amplitude, bias, frequency and number of cycles through the human-machine interface. The waveform generator calculates the current pressure setpoint in real time based on these parameters. This setpoint is used as the input target of the PID controller. The PID controller outputs the corresponding control signal to drive the electro-proportional valve to act, so that the pressure in the cavity changes in real time with the waveform setpoint. When it is necessary to evaluate the creep characteristics of the membrane material under constant load, the static loading control subunit is selected. When it is necessary to evaluate the fatigue characteristics and dynamic response of the membrane material under alternating load, the dynamic loading control subunit is selected.

[0029] Example 3, the following description uses ETFE (ethylene-tetrafluoroethylene copolymer) film material for photovoltaic encapsulation as an example; Take a 200mm×200mm ETFE membrane material sample with a thickness of 100μm, and equilibrate it in an environment with a temperature of 23±2℃ and a relative humidity of 50±5% for no less than 24 hours. Then, install the sample on the circular clamp of the sealed test chamber with an inner diameter of 80mm. After the sample is clamped, an effective test area with a diameter of 80mm is formed. The sample is kept flat and taut. The sealed chamber is closed, the temperature is set to 65℃, the relative humidity is set to 85%, the irradiance is set to 1000W / m², the temperature control PID maintains the temperature at 65±1℃, the humidifier stabilizes the humidity at 85±3%, the xenon lamp adjusts the output power through PWM to stabilize the irradiance at 1000±50W / m², the thermocouple on the back of the sample collects the temperature every 10 seconds, and automatically reduces the power for protection when the temperature exceeds 100℃. Static air pressure loading: The pressure is continuously increased at a rate of 0.5 kPa / s. The pressure sensor collects the cavity pressure value at 100 Hz. The high-speed camera collects speckle images of the sample surface at 50 frames / second. The image processing unit performs sub-pixel level edge localization, calculates the displacement of the sample center point from the surface and the in-plane strain distribution, and plots the pressure-center displacement curve in real time until the sample ruptures. The rupture pressure is recorded as the fracture strength. According to the theory of small deflection of a circular thin plate with peripheral fixed support, the pressure p and the central displacement w during the elastic deformation stage satisfy: p = (16E·t³) / (3(1-ν²)R) 4 )·w, where t=100μm, ν=0.42, R=40mm, extract the slope of the linear segment of the curve, and substitute it into the formula to calculate the elastic modulus; Dynamic air pressure loading: The pressure was controlled to vary periodically between 10-40 kPa at 0.05 Hz according to the sinusoidal function P(t)=15×sin(2π×0.05×t)+25 (kPa). The dynamic response and fatigue characteristics of the sample under alternating load were analyzed. The images acquired by the camera are preprocessed by histogram equalization and median filtering. The crack edges are extracted using the Canny operator (low threshold 50, high threshold 150). The crack length (accumulated point by point along the center line) and crack width (average vertical distance between edges) are calculated. The crack propagation rate is calculated through continuous frame images. When the crack length is ≥3mm or the crack width is ≥0.3mm, an early warning signal is generated. Optical testing was conducted concurrently with mechanical testing. Transmittance: A xenon lamp source was split by a monochromator to output monochromatic light of 300-1100 nm (step size 10 nm), which was perpendicularly irradiated onto the sample. An integrating sphere collected the transmitted light, and a detector measured the light intensity. Transmittance at each wavelength was calculated using T(λ) = I(λ) / I0(λ) × 100%, with particular attention paid to the 400-700 nm and 900-1100 nm bands. Haze: According to ASTM D1003 standards, parallel light was incident on the sample. An integrating sphere collected the total transmitted light and the scattered transmitted light, respectively. The haze value was calculated as Haze = Ts / Tt × 100%, where Ts is the total transmitted light flux and Tt is the scattered transmitted light flux. Surface defects: A high-resolution camera acquired grayscale images of the sample's transmission. After Gaussian filtering, Otsu adaptive threshold segmentation was used to extract defect regions. Connected component marking was used to statistically analyze the number, area, and location distribution of defects. The clock synchronization module generates a 100Hz master clock to trigger pressure sensor sampling, and a 50Hz frequency division to trigger camera exposure. The environmental sensor collects data synchronously at 1Hz. All data are stored in the database after being stamped with a unified timestamp (millisecond level), and an index association is established between environmental parameters and mechanical data and image data. The weighted configuration of the ETFE film for photovoltaic encapsulation is as follows: transmittance (550nm) 0.30, haze 0.15, elastic modulus 0.20, tensile strength 0.20, and surface defect density 0.15. Measured values ​​are: transmittance 92.5% (Grade A), haze 4.2% (Grade A), elastic modulus 820MPa (Grade A), tensile strength 52MPa (Grade A), and surface defect density 0.8 defects / m² (Grade B). After quantification (A=100 points, B=70 points), the weighted sum is: 100×0.30+100×0.15+100×0.20+100×0.20+70×0.15=95.5 points. ≥90 points indicates a superior product. Therefore, this ETFE sample is rated as a superior product, and a complete test report is generated.

[0030] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0031] Obviously, the embodiments described above are merely some embodiments of the present invention, not all embodiments. The accompanying drawings show preferred embodiments of the present invention, but do not limit the patent scope of the present invention. The present invention can be implemented in many different forms; rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure of the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing specific embodiments, or make equivalent substitutions for some of the technical features. Any equivalent structures made using the content of this specification and drawings, directly or indirectly applied to other related technical fields, are similarly within the patent protection scope of this invention.

Claims

1. A method for detecting the performance of a novel membrane material, characterized by, Includes the following steps: Obtain a sample of the membrane material to be tested, place the sample in a closed testing environment and keep it under tension; set the environmental parameters of the closed testing environment, including at least one of temperature, humidity and irradiation parameters. A uniform pressure load is applied to the sample by air pressure loading to induce out-of-surface deformation of the sample. During the loading process, load data and sample deformation data are collected synchronously at a predetermined sampling frequency. Based on the collected load and deformation data, the mechanical property parameters of the sample are calculated, including elastic modulus and fracture strength. During the mechanical property testing, the physical property parameters of the sample are obtained through optical detection methods. The physical property parameters include at least one of transmittance, haze, and surface defect parameters. By performing correlation analysis between mechanical and physical performance parameters, a comprehensive performance evaluation result of the sample is generated.

2. The performance testing method for the novel membrane material according to claim 1, characterized in that, Pneumatic loading methods include static pneumatic loading mode and dynamic pneumatic loading mode; In static air pressure loading mode, the gas pressure in the sealed detection environment is controlled to continuously increase to the target pressure value at a predetermined rate. In dynamic air pressure loading mode, the gas pressure in the sealed detection environment is controlled to change periodically according to a preset waveform, which includes at least one of sine wave, square wave and triangle wave.

3. The performance testing method for the novel membrane material according to claim 1, characterized in that, The sample deformation data is acquired through non-contact optical measurement, including: continuously acquiring image sequences of the sample surface; performing subpixel-level edge localization processing on each frame of the image sequence to extract the current edge contour of the sample; and calculating the out-of-plane displacement field and in-plane strain field of the sample during the loading process based on the offset of the current edge contour relative to the initial edge contour.

4. The performance testing method for the novel membrane material according to claim 3, characterized in that, It also includes online crack identification: performing illumination equalization and noise filtering preprocessing on the current image in the image sequence; Edge detection based on gradient operator is performed on the preprocessed image to extract the crack edges present on the sample surface; crack parameters are calculated based on the geometric features of the crack edges, including at least one of crack length, crack width, crack area and crack propagation rate; when the crack length or crack width exceeds a preset warning threshold, a crack warning signal is generated.

5. The performance testing method for the novel membrane material according to claim 1, characterized in that, When uniform pressure is applied, the elastic modulus is calculated based on the functional relationship between the uniform pressure value and the displacement value of the center point of the sample.

6. The performance testing method for the novel membrane material according to claim 1, characterized in that, Optical inspection methods include transmittance testing and surface defect detection; Transmittance detection includes: vertically irradiating the sample surface with incident light, collecting the transmitted light that passes through the sample, measuring the light intensity of the transmitted light at different wavelengths, and calculating the spectral transmittance curve based on the ratio of the incident light intensity to the transmitted light intensity. Surface defect detection includes: acquiring high-resolution grayscale images of the sample surface, extracting defect regions from the grayscale images using a threshold-based segmentation algorithm, and statistically analyzing the number, area, and location distribution of defect regions.

7. The performance testing method for the novel membrane material according to claim 1, characterized in that, The irradiation parameters are controlled as follows: the output power of the irradiation source is adjusted by pulse width modulation according to the preset irradiation intensity setting value to maintain the irradiation intensity at the set value; during the irradiation process, the temperature value of the sample surface is collected at preset time intervals, and when the temperature value exceeds the preset temperature threshold, the output power of the irradiation source is reduced or irradiation is paused.

8. The performance testing method for the novel membrane material according to claim 1, characterized in that, The comprehensive performance evaluation results are generated by comparing the mechanical and physical performance parameters with their corresponding standard thresholds to obtain the rating results of each individual parameter; calculating the comprehensive score by weighting and summing the rating results of each individual parameter according to the preset weighting coefficients; and determining the quality grade of the sample based on the comprehensive score.

9. A novel membrane material performance testing system, used to implement the novel membrane material performance testing method as described in any one of claims 1-8, characterized in that, include: Environmental control unit, used to adjust the environmental parameters of the sealed detection environment; The pneumatic loading control unit is used to apply a uniform pressure load to the membrane material sample installed in the closed detection environment by controlling the gas pressure change in the closed detection environment. The data synchronization acquisition unit is used to simultaneously acquire load data and sample deformation data during the air pressure loading process; The mechanical property calculation unit is used to calculate the mechanical property parameters of the sample based on the collected load data and deformation data. The mechanical property parameters include elastic modulus and fracture strength. An optical performance testing unit is used to acquire physical performance parameters of a sample through optical detection during or between mechanical performance testing operations. The physical performance parameters include at least one of transmittance, haze, and surface defect parameters. The comprehensive evaluation unit is used to perform correlation analysis between mechanical and physical performance parameters to generate comprehensive performance evaluation results for the sample.

10. The performance testing system for the novel membrane material according to claim 9, characterized in that, The pneumatic loading control unit includes a static loading control subunit and a dynamic loading control subunit; The static loading control subunit is used to continuously increase the gas pressure in the sealed detection environment to the target pressure value at a predetermined rate using a closed-loop control method. The dynamic loading control subunit is used to make the gas pressure in the closed detection environment change periodically according to a preset waveform.

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