Large-breadth high-refresh-rate dynamic and static pressure sampling system and high-refresh sampling method

Abstract

The invention discloses a large-breadth high-refresh-rate dynamic and static pressure sampling system and a high-refresh sampling method.The large-breadth high-refresh-rate dynamic and static pressure sampling system comprises a plurality of pressure acquisition units, a dual-mode synchronous clock unit and a post-stage data processing unit which are spliced in parallel, the dual-mode synchronous clock unit is electrically connected with the pressure acquisition units, and the post-stage data processing unit is electrically connected with the dual-mode synchronous clock unit. The dual-mode synchronous clock unit is connected with the pressure acquisition units to provide a unified time sequence reference, the pressure acquisition units autonomously perform sampling according to signals of the dual-mode synchronous clock unit, and the acquired data are marked with timestamps and then uploaded to the post-stage data processing unit, so that high-refresh sampling and data synchronous restoration of a large-format detection area are realized. By the adoption of the large-breadth high-refresh-rate dynamic and static pressure sampling system and the high-refresh-rate sampling method, collaborative optimization of detection area expandability and detection performance (refresh rate and precision) is achieved.

Description

Technical Field

[0001] This invention relates to the field of refresh sampling technology, and in particular to a large-format high refresh rate dynamic and static pressure sampling system and a high refresh sampling method. Background Technology

[0002] Pressure dynamic and static detection technology has been widely used in data acquisition scenarios across various fields. Existing detection equipment is mainly small and fixed in size, achieving data acquisition through static or dynamic pressure detection modes. Its core detection logic is as follows: the main control unit uses a row-by-row, column-by-column cyclic scanning method to sequentially read the pressure parameters of each detection point in the sensor array; however, in large-area detection scenarios, the detection area is positively correlated with the number of sensor detection points, and the total time to completely scan all detection points increases with the increase in the number of detection points, making high refresh rate detection difficult to achieve.

[0003] The existing technology has the following key defects and shortcomings: 1. The contradiction between refresh rate and accuracy in small single devices: For small, fixed-size devices, the design of sequentially scanning each sensor point using a single main control unit can recover dynamic pressure changes based on the scanning time cycle, but there is an inherent contradiction: Taking a 50×50 density pressure sensor matrix as an example, when the detection time of a single sensor is 5μs (the minimum reasonable time to ensure detection accuracy; too short a time will lead to insufficient signal acquisition and decreased accuracy), the system refresh detection frequency can reach about 70Hz; if you try to increase the refresh rate by shortening the detection time of a single sensor, you will directly sacrifice the accuracy of the detection results, making it difficult to balance the two.

[0004] 2. Refresh Rate Bottleneck in Large-Area Detection: If a row-by-row, column-by-column scanning method is used to achieve large-area detection, the number of detection points increases synchronously with the detection area, further extending the total scanning time and significantly reducing the refresh rate. For example, in a 100×100 pressure sensor matrix, when the detection time for a single pressure point is 5μs, the time to completely refresh all sensors reaches 100×100×5μs=50000μs, reducing the equivalent maximum refresh rate to less than 20Hz, which cannot meet the requirements for high refresh rate detection.

[0005] 3. Synchronization Error Issues in Multi-Unit Splicing: To address large-area detection needs, some solutions employ a splicing design of multiple small acquisition units. However, each small acquisition unit has an independent timing system, resulting in initial timing errors that accumulate and increase over time. Even if each unit has the same acquisition frequency, its sampling time remains relatively independent: based on absolute time, the absolute time relationship of the output results after the input signals of multiple units are acquired at the same moment is random, with the maximum frame time error equivalent to the single-frame sampling interval. Based on this type of data with time errors, the PC host computer cannot accurately restore the true time correlation between the input signals of each acquisition unit, making it difficult to effectively restore the synchronization relationship of the acquired signals in the output data of the large-format system, directly affecting the accuracy of dynamic and static pressure detection and analysis.

[0006] Furthermore, in practical applications, it is necessary to send acquisition commands containing timestamps to each small acquisition unit through a PC host computer. After receiving data packets from all units, the data is then spliced ​​together based on the timestamps in the data packets to restore the data of the entire acquisition system. This process is not only cumbersome, but the communication time between the PC and each unit also accumulates randomly, further reducing the system's response efficiency and making it unsuitable for high real-time detection requirements. Summary of the Invention

[0007] The purpose of this invention is to provide a large-format, high-refresh-rate dynamic and static pressure sampling system and a high-refresh-rate sampling method to solve the above-mentioned technical problems.

[0008] To achieve the above objectives, the present invention provides a large-format high refresh rate dynamic and static pressure sampling system, comprising multiple pressure acquisition units connected in parallel, a dual-mode synchronous clock unit, and a subsequent data processing unit. The dual-mode synchronous clock unit is electrically connected to the multiple pressure acquisition units to provide a unified timing reference. Each pressure acquisition unit autonomously performs sampling based on the signal from the dual-mode synchronous clock unit, timestamps the acquired data, and uploads it to the subsequent data processing unit, thereby realizing high refresh rate sampling and synchronous data restoration of a large-format detection area.

[0009] Preferably, each pressure acquisition unit consists of a sensor array with identical parameters and a sensor main control board electrically connected to the corresponding sensor array; The dual-mode synchronous clock unit includes a voltage-controlled crystal oscillator (VCO), a temperature controller, and a GPS receiver module. The PPS signal output of the GPS receiver module is electrically connected to the clock calibration signal input of the VCO, which is used to transmit the PPS signal to the VCO. By comparing the error between the PPS signal and the VCO's own clock, the control voltage of the VCO is adjusted. The temperature control output of the temperature controller is coupled to the temperature adjustment interface of the VCO to maintain the constant temperature of the VCO. The horizontal and vertical synchronization signal outputs of the pressure-controlled crystal oscillator are electrically connected to the main control boards of the sensors of multiple pressure acquisition units. The pressure-controlled crystal oscillator is also connected in series with the bus interface of the main control boards of the sensors of multiple pressure acquisition units via a communication bus interface. The main control board of the sensors receives the horizontal synchronization signal, the vertical synchronization signal and the absolute timestamp generated by the pressure-controlled crystal oscillator, and locks its own time system with the synchronization time. Taking the rising edge of the vertical synchronization signal as the starting point of a single frame sampling and the falling edge of the horizontal synchronization signal as the starting point of a single line sampling, the board controls the corresponding sensor array to collect pressure electrical signals point by point. The collected raw electrical signals are then preprocessed, and a corresponding absolute timestamp is added to each frame of data. Finally, during the synchronization idle time, the preprocessed electrical signals with absolute timestamps are independently uploaded to the post-data processing unit. The synchronization idle time is the total time for data processing and transmission.

[0010] A high refresh rate sampling method for a large-format, high refresh rate dynamic and static pressure sampling system includes the following steps: S1. Clock source initialization and calibration when satellite is valid: The dual-mode synchronous clock unit connects to the PPS signal output by the GPS receiver module and activates the temperature controller to maintain a constant temperature environment for the voltage-controlled crystal oscillator; using the falling edge of the PPS signal as the time reference point, it compares the 1-second clock signal generated by its own crystal oscillator with the signal, and calculates the average error after accumulating a set number of counting cycles. The error is corrected by adjusting the control voltage of the voltage-controlled crystal oscillator until the error is ≤5ppm; the temperature parameters and control voltage parameters of the voltage-controlled crystal oscillator are recorded synchronously and stored as reference data. S2, Clock Source Broadcast Synchronization Signal and Timestamp: Based on the calibrated clock, generate horizontal synchronization signal and vertical synchronization signal, and generate absolute timestamp; broadcast the horizontal synchronization signal, vertical synchronization signal and timestamp to all sensor main control boards simultaneously through the horizontal synchronization signal output terminal, the vertical synchronization signal output terminal and the communication bus interface; S3. Sensor Main Control Board Synchronous Sampling and Data Labeling: After receiving the line synchronization signal, field synchronization signal, and timestamp, the sensor main control board locks its own time system with the synchronization signal; and takes the rising edge of the field synchronization signal as the starting point of a single frame sampling and the falling edge of the line synchronization signal as the starting point of a single row sampling, controls the corresponding sensor array to collect the pressure electrical signal of each sensor point row by row and column by column; then preprocesses the raw data collected in each frame and appends the corresponding timestamp. S4. Independent data upload of sensor main control boards: During the synchronization idle time, preprocessed data with absolute timestamps is independently uploaded to the subsequent data processing unit through the data transmission interface, and each sensor main control board completes the transmission in parallel. S5. Post-processing data stitching and integration: The post-processing data unit receives pre-processed data with absolute timestamps uploaded by all sensor main control boards, stitches the collected data of each sensor array according to the time dimension based on the absolute timestamps, restores the pressure distribution and pressure change process over time in the large-format detection area, and outputs complete large-format dynamic and static pressure detection data.

[0011] Preferably, in step S1, the target control voltage of the voltage-controlled crystal oscillator is... The expression is as follows: ; in, ; ; In the formula, This indicates the current actual control voltage of the voltage-controlled crystal oscillator; This indicates the adjustment amount of the control voltage of the voltage-controlled crystal oscillator; This indicates the current actual average frequency error of the voltage-controlled crystal oscillator, and , This indicates that the voltage-controlled crystal oscillator is in The actual cumulative clock pulses within each PPS cycle This indicates that the voltage-controlled crystal oscillator is in Ideal cumulative clock pulse count within one PPS cycle; Indicates the target frequency error; This indicates the frequency error difference that needs to be corrected; This indicates the voltage-frequency sensitivity of the voltage-controlled crystal oscillator.

[0012] Preferably, in step S1, if the satellite signal is interrupted, the stored reference data of voltage-controlled crystal oscillator temperature and control voltage are automatically retrieved; the temperature of the voltage-controlled crystal oscillator is adjusted by the temperature controller, and the control voltage is adjusted synchronously to restore the temperature and pressure environment during calibration and maintain the clock output accuracy.

[0013] The preferred formula for adjusting the temperature of a voltage-controlled crystal oscillator is as follows: ; in, ; In the formula, Indicates temperature regulation bias; This indicates the temperature reference data of the voltage-controlled crystal oscillator stored after calibration when the satellite signal is valid; This indicates the target operating temperature of the voltage-controlled crystal oscillator when the satellite signal is interrupted. This indicates the current operating temperature of the voltage-controlled crystal oscillator when the satellite signal is interrupted. The voltage adjustment formula is as follows: ; in, ; In the formula, This indicates the adjustment bias of the control voltage; This indicates the voltage-controlled crystal oscillator control voltage reference data stored after calibration when the satellite signal is valid; This indicates the current control voltage of the voltage-controlled crystal oscillator when the satellite signal is interrupted; This indicates the target control voltage of the voltage-controlled crystal oscillator when the satellite signal is interrupted.

[0014] Preferably, in steps S2 and S3, the duration of the horizontal synchronization signal... The calculation formula is as follows: ; In the formula, Indicates the number of columns in a single sensor array; This indicates the acquisition time of a single pressure sensor point; Interval time of field synchronization signal The calculation formula is as follows: ; In the formula, Indicates the number of rows in a single sensor array; Indicates the duration of synchronization idle time; The formula for calculating the synchronization idle time duration mentioned in step S4 is as follows: ; In the formula, This represents the total time it takes for a single sensor array to complete all row scans.

[0015] Therefore, the present invention employs the above-mentioned large-format high refresh rate dynamic and static pressure sampling system and high refresh rate sampling method, which has the following beneficial effects: 1. Significantly improved refresh rate: Through the design of parallel sampling by multiple acquisition units and independent data transmission during synchronous idle time, the total acquisition time of a single frame is greatly shortened. For example, after splitting the small-format sensor matrix, the equivalent refresh rate is increased to 50Hz, which meets the high real-time requirements of large-format dynamic pressure detection. 2. High synchronization accuracy: Each acquisition unit uses a unified high-precision clock source as the timing reference, with a clock error of ≤5ppm. All acquired data are marked with an absolute timestamp, and the subsequent system can accurately restore the time correlation of signals from each unit, completely solving the synchronization error problem of traditional multi-unit splicing and improving the accuracy of dynamic and static pressure detection and analysis. 3. Flexible expansion of detection area: Supports unlimited number of pressure acquisition units connected in parallel, and all units have the same parameters. The detection area can be customized according to needs (flexibly adjusted from small to large area), adapting to various scenarios such as gait detection and large-area industrial pressure monitoring. 4. Simplified operation process and optimized efficiency: There is no need for the PC host computer to issue acquisition commands to each unit. Each unit autonomously advances the sampling, processing and transmission process according to the clock source synchronization signal, saving scheduling waiting time and avoiding the problem of random accumulation of communication time, which greatly improves the system response efficiency. 5. Stable and reliable clock accuracy: It adopts a dual mode of "satellite time synchronization calibration + environmental restoration compensation". When the satellite signal is valid, the clock is accurately calibrated through 1PPS signal. When the signal is invalid, the reference data is called to restore the temperature and pressure environment, ensuring the continuous stability of clock accuracy and avoiding sampling interruption or data inaccuracy. 6. Balancing detection accuracy and performance: The acquisition time of a single sensor point is maintained within a reasonable range of ≥5μs to ensure detection accuracy. At the same time, the traditional limitation of "mutual exclusion between accuracy and refresh rate" is broken through the synchronous design, achieving a synergistic balance between the two.

[0016] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0017] Figure 1 This is a structural block diagram of a large-format, high-refresh-rate dynamic and static pressure sampling system according to the present invention. Figure 2 This is a flowchart of a high refresh rate sampling method for a large-format high refresh rate dynamic and static pressure sampling system according to the present invention. Figure 3 This is a schematic diagram of the parallel timing of multi-module parallel (64x64 dot matrix) sampling and transmission described in the verification test of this invention. Figure 4 This is a schematic diagram of the timing decomposition of single-module single-frame sampling described in the verification test of this invention. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely illustrative of the embodiments of the present invention and are not intended to limit the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of this application. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout.

[0019] It should be noted that the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion, such as a process, method, system, product, or server that includes a series of steps or units, not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such process, method, product, or device.

[0020] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0021] like Figure 1 As shown, a large-format high refresh rate dynamic and static pressure sampling system includes multiple pressure acquisition units connected in parallel, a dual-mode synchronous clock unit, and a subsequent data processing unit. The dual-mode synchronous clock unit is electrically connected to the multiple pressure acquisition units to provide a unified timing reference. Each pressure acquisition unit performs sampling autonomously based on the signal from the dual-mode synchronous clock unit, timestamps the acquired data, and uploads it to the subsequent data processing unit, thereby realizing high refresh rate sampling and synchronous data restoration of the large-format detection area.

[0022] Each pressure acquisition unit consists of a sensor array with identical parameters and a corresponding sensor control board electrically connected to the sensor array. The dual-mode synchronous clock unit includes a voltage-controlled crystal oscillator (VCO), a temperature controller, and a GPS receiver module. The PPS signal output of the GPS receiver module is electrically connected to the clock calibration signal input of the VCO, used to transmit the PPS signal to the VCO. By comparing the error between the PPS signal and the VCO's own clock, the control voltage of the VCO is adjusted. The temperature control output of the temperature controller is coupled to the temperature adjustment interface of the VCO to maintain a constant temperature state. The horizontal and vertical synchronization signal outputs of the VCO are both electrically connected to the sensor control boards of multiple pressure acquisition units. The system is connected, and the pressure-controlled crystal oscillator is also connected in series with the bus interface of the sensor main control board of multiple pressure acquisition units via the communication bus interface. The sensor main control board receives the line synchronization signal, field synchronization signal and absolute timestamp generated by the pressure-controlled crystal oscillator, and locks its own time system with the synchronization time. Taking the rising edge of the field synchronization signal as the starting point of a single frame sampling and the falling edge of the line synchronization signal as the starting point of a single line sampling, it controls the corresponding sensor array to collect pressure electrical signals point by point. Then, it preprocesses the collected raw electrical signals and adds the corresponding absolute timestamp to each frame of data. Finally, during the synchronization idle time, the preprocessed electrical signals with absolute timestamps are independently uploaded to the post-data processing unit. The synchronization idle time is the total time for data processing and transmission.

[0023] like Figure 2 As shown, a high refresh rate sampling method for a large-format high refresh rate dynamic and static pressure sampling system includes the following steps: S1. Clock source initialization and calibration when satellite is valid: The dual-mode synchronous clock unit connects to the PPS signal output by the GPS receiver module and activates the temperature controller to maintain a constant temperature environment for the voltage-controlled crystal oscillator; using the falling edge of the PPS signal as the time reference point, it compares the 1-second clock signal generated by its own crystal oscillator with the signal, and calculates the average error after accumulating a set number of counting cycles. The error is corrected by adjusting the control voltage of the voltage-controlled crystal oscillator until the error is ≤5ppm; the temperature parameters and control voltage parameters of the voltage-controlled crystal oscillator are recorded synchronously and stored as reference data. S2, Clock Source Broadcast Synchronization Signal and Timestamp: Based on the calibrated clock, generate horizontal synchronization signal and vertical synchronization signal, and generate absolute timestamp; broadcast the horizontal synchronization signal, vertical synchronization signal and timestamp to all sensor main control boards simultaneously through the horizontal synchronization signal output terminal, the vertical synchronization signal output terminal and the communication bus interface; S3. Sensor Main Control Board Synchronous Sampling and Data Labeling: After receiving the line synchronization signal, field synchronization signal, and timestamp, the sensor main control board locks its own time system with the synchronization signal; and takes the rising edge of the field synchronization signal as the starting point of a single frame sampling and the falling edge of the line synchronization signal as the starting point of a single row sampling, controls the corresponding sensor array to collect the pressure electrical signal of each sensor point row by row and column by column; then preprocesses the raw data collected in each frame and appends the corresponding timestamp. S4. Independent data upload of sensor main control boards: During the synchronization idle time, preprocessed data with absolute timestamps is independently uploaded to the subsequent data processing unit through the data transmission interface, and each sensor main control board completes the transmission in parallel. S5. Post-processing data stitching and integration: The post-processing data unit receives pre-processed data with absolute timestamps uploaded by all sensor main control boards, stitches the collected data of each sensor array according to the time dimension based on the absolute timestamps, restores the pressure distribution and pressure change process over time in the large-format detection area, and outputs complete large-format dynamic and static pressure detection data.

[0024] Preferably, in step S1, the target control voltage of the voltage-controlled crystal oscillator is... The expression is as follows: ; in, ; ; In the formula, This indicates the current actual control voltage of the voltage-controlled crystal oscillator; This indicates the adjustment amount of the control voltage of the voltage-controlled crystal oscillator; This indicates the current actual average frequency error of the voltage-controlled crystal oscillator, and , This indicates that the voltage-controlled crystal oscillator is in The actual cumulative clock pulses within each PPS cycle This indicates that the voltage-controlled crystal oscillator is in Ideal cumulative clock pulse count within one PPS cycle; Indicates the target frequency error; This indicates the frequency error difference that needs to be corrected; This indicates the voltage-frequency sensitivity of the voltage-controlled crystal oscillator.

[0025] Preferably, in step S1, if the satellite signal is interrupted, the stored reference data of voltage-controlled crystal oscillator temperature and control voltage are automatically retrieved; the temperature of the voltage-controlled crystal oscillator is adjusted by the temperature controller, and the control voltage is adjusted synchronously to restore the temperature and pressure environment during calibration and maintain the clock output accuracy.

[0026] The preferred formula for adjusting the temperature of a voltage-controlled crystal oscillator is as follows: ; in, ; In the formula, Indicates temperature regulation bias; This indicates the temperature reference data of the voltage-controlled crystal oscillator stored after calibration when the satellite signal is valid; This indicates the target operating temperature of the voltage-controlled crystal oscillator when the satellite signal is interrupted. This indicates the current operating temperature of the voltage-controlled crystal oscillator when the satellite signal is interrupted. The voltage adjustment formula is as follows: ; in, ; In the formula, This indicates the adjustment bias of the control voltage; This indicates the voltage-controlled crystal oscillator control voltage reference data stored after calibration when the satellite signal is valid; This indicates the current control voltage of the voltage-controlled crystal oscillator when the satellite signal is interrupted; This indicates the target control voltage of the voltage-controlled crystal oscillator when the satellite signal is interrupted.

[0027] Preferably, in steps S2 and S3, the duration of the horizontal synchronization signal... The calculation formula is as follows: ; In the formula, Indicates the number of columns in a single sensor array; This indicates the acquisition time of a single pressure sensor point; Interval time of field synchronization signal The calculation formula is as follows: ; In the formula, Indicates the number of rows in a single sensor array; Indicates the duration of synchronization idle time; The formula for calculating the synchronization idle time duration mentioned in step S4 is as follows: ; In the formula, This represents the total time it takes for a single sensor array to complete all row scans.

[0028] Verification test Experimental objective: To verify the effect of the "multi-module parallel connection + dual-mode synchronous clock" design of this invention on improving the refresh rate of a large-format pressure dynamic and static sampling system, to compare the refresh time, refresh rate and data synchronization performance of the traditional solution (no synchronous clock, PC unit-by-unit triggering) and the solution of this invention, and to verify the feasibility and superiority of the technical solution.

[0029] Test conditions: Pressure sensor single-point acquisition time: 5μs (the minimum reasonable value to ensure detection accuracy); Transmission rate: 100Mbps (traditional solution), 1000Mbps (the solution of this invention); Sensor matrix specifications: 32×32 (small format single module, a total of 1024 sensor points), 1024×1024 (large format, a total of 1,048,576 sensor points); Module split specifications: The 1024×1024 matrix is ​​split into 16 pressure acquisition units of 256×256 specifications (each unit has the same parameters); Synchronization clock unit: including GPS receiver module, pressure-controlled crystal oscillator and temperature controller, clock error calibrated to ≤5ppm.

[0030] Test metrics: Total refresh time per frame (including acquisition, data processing, transmission and scheduling time); System equivalent refresh rate (1 / total refresh time per frame); Data synchronization accuracy (timestamp deviation of data in each module).

[0031] Experimental steps: (I) Traditional scheme test (control group: no synchronous clock, PC unit-by-unit trigger): 1. Small area single module test (64×64): First, a single pressure acquisition unit is used, and the PC host computer issues an acquisition trigger command with a timestamp; then the acquisition time T2 (64×64×5μs=20480μs=20.5ms), data processing time (ignore), transmission time T4 (8192byte÷1000Mbps=0.082ms) and PC scheduling time T1 (at least 3ms) are recorded; finally, the total refresh time of a single frame and the equivalent refresh rate (1000 / (20.5+3+0.082)=35hz) are calculated. 2. Large format unsplit test (1024×1024): First, a single pressure acquisition unit was used, and the line-by-line scanning mode was followed; then the acquisition time T2 (1024×1024×5μs=5242880μs=5.242s) and transmission time T4 (20.9M÷1000Mbps=20.9ms) were recorded; finally, the total refresh time of a single frame and the equivalent refresh rate (1 / (5.242+0.02)) were calculated. 3. Large Format (1024×1024) Module Splitting Test (256 64×64 modules): First, after splitting, each module runs independently. The PC sends trigger commands to each module and receives data. Then, record the single-module acquisition time T2 (64×64×5μs=20480μs=20.5ms), data processing time T3 (consistent for each module), PC scheduling time T1 (T1 incremented 256 times for a single module), and transmission time T4 (T4 incremented 256 times for a single module; total transmission time at 1000Mbps is 0.02s). Since T1 is a two-way response communication, it is at least 3ms. Calculate the total refresh time for a single frame: (T1×1024+T2+T3+T4×1024)=3 256 + 20.5 + 0.2 = 788.7ms. This is 5 times faster than the unsplit test, but the refresh rate is still very low.

[0032] (II) Testing of the Invention Scheme (Experimental Group: Multi-module Parallel Connection + Dual-mode Synchronous Clock): Large-format module splitting test (256 64×64 modules), such as... Figure 3 and Figure 4As shown, each small-area single module is (64×64). A dual-mode synchronous clock source broadcasts synchronization signals and timestamps to all small-area single modules, eliminating the need for trigger commands from the PC. Each pressure acquisition unit achieves time synchronization through the synchronous clock signal, autonomously advancing the sampling, data processing, and transmission processes. The cyclic timing of each small-area single module includes acquisition time T2 = 20.5ms, transmission time T4 = 0.2ms, and synchronization idle time (the total time for data processing and transmission is slightly increased). Due to the high-precision clock source synchronizing the entire system, all the split small modules can sequentially and interleavedly complete the above steps. Assuming that the data transmission time is not compressible, the maximum data transmission time needs to be 20.9ms, which is greater than the acquisition time of each small-area single module. In this way, the data acquisition refresh time of the entire module can be shortened to at least 20.9ms, with an equivalent refresh rate of 1000 / 20.9 = 47.8Hz.

[0033] As can be seen, the present invention completely eliminates the PC host computer scheduling time (T1=0) through the design of "dual-mode synchronous clock unit + multi-module autonomous synchronous sampling", which greatly shortens the total refresh time of a single frame; in small-format scenarios, the present invention increases the refresh rate to 50Hz, realizing the coordinated optimization of large-format detection and high refresh rate; The data timestamp deviation of each pressure acquisition unit is ≤5ppm, and the subsequent data processing unit can accurately splice the data according to the timestamp, which verifies the high synchronization accuracy of the synchronous clock design. In summary, this invention effectively solves the problem of mutual exclusion between large-format printing and high refresh rate and high synchronization accuracy in traditional technologies through the design of "parallel expansion of module area + synchronous clock to ensure performance". The technical solution has significant advantages and feasibility, thus proving the effectiveness of this invention.

[0034] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A large-format, high-refresh-rate dynamic and static pressure sampling system, characterized in that: It includes multiple pressure acquisition units connected in parallel, a dual-mode synchronous clock unit, and a subsequent data processing unit. The dual-mode synchronous clock unit is electrically connected to multiple pressure acquisition units to provide a unified timing reference. Each pressure acquisition unit performs sampling autonomously based on the signal from the dual-mode synchronous clock unit, timestamps the acquired data, and uploads it to the subsequent data processing unit, realizing high refresh rate sampling and synchronous data restoration in a large-format detection area.

2. The large-format high refresh rate dynamic and static pressure sampling system according to claim 1, characterized in that: Each pressure acquisition unit consists of a sensor array with identical parameters and a corresponding sensor main control board connected to the sensor array; The dual-mode synchronous clock unit includes a voltage-controlled crystal oscillator (VCO), a temperature controller, and a GPS receiver module. The PPS signal output of the GPS receiver module is electrically connected to the clock calibration signal input of the VCO, which is used to transmit the PPS signal to the VCO. By comparing the error between the PPS signal and the VCO's own clock, the control voltage of the VCO is adjusted. The temperature control output of the temperature controller is coupled to the temperature adjustment interface of the VCO to maintain the constant temperature of the VCO. The horizontal and vertical synchronization signal outputs of the pressure-controlled crystal oscillator are electrically connected to the main control boards of the sensors of multiple pressure acquisition units. The pressure-controlled crystal oscillator is also connected in series with the bus interface of the main control boards of the sensors of multiple pressure acquisition units via a communication bus interface. The main control board of the sensors receives the horizontal synchronization signal, the vertical synchronization signal and the absolute timestamp generated by the pressure-controlled crystal oscillator, and locks its own time system with the synchronization time. Taking the rising edge of the vertical synchronization signal as the starting point of a single frame sampling and the falling edge of the horizontal synchronization signal as the starting point of a single line sampling, the board controls the corresponding sensor array to collect pressure electrical signals point by point. The collected raw electrical signals are then preprocessed, and a corresponding absolute timestamp is added to each frame of data. Finally, during the synchronization idle time, the preprocessed electrical signals with absolute timestamps are independently uploaded to the post-data processing unit. The synchronization idle time is the total time for data processing and transmission.

3. The high refresh rate sampling method for a large-format high refresh rate dynamic and static pressure sampling system as described in claim 2, characterized in that: Includes the following steps: S1. Clock source initialization and calibration when satellite is valid: The dual-mode synchronous clock unit connects to the PPS signal output by the GPS receiver module and starts the temperature controller to maintain a constant temperature environment for the voltage-controlled crystal oscillator; using the falling edge of the PPS signal as the time reference point, it compares the 1-second clock signal generated by its own crystal oscillator, accumulates to the set number of counting cycles to calculate the average error, and corrects the error by adjusting the control voltage of the voltage-controlled crystal oscillator until the error is ≤5ppm; Simultaneously record the temperature parameters and control voltage parameters of the voltage-controlled crystal oscillator and store them as reference data; S2, Clock Source Broadcast Synchronization Signal and Timestamp: Based on the calibrated clock, generate horizontal synchronization signal and vertical synchronization signal, and generate absolute timestamp; broadcast the horizontal synchronization signal, vertical synchronization signal and timestamp to all sensor main control boards simultaneously through the horizontal synchronization signal output terminal, the vertical synchronization signal output terminal and the communication bus interface; S3. Sensor main control board synchronous sampling and data labeling: After receiving the line synchronization signal, field synchronization signal and timestamp, the sensor main control board locks its own time system with the synchronization signal; and takes the rising edge of the field synchronization signal as the starting point of single frame sampling and the falling edge of the line synchronization signal as the starting point of single row sampling, and controls the corresponding sensor array to collect the pressure electrical signal of each sensor point row by row and column by column. The raw data collected for each frame is then preprocessed and a corresponding timestamp is appended. S4. Independent data upload of sensor main control boards: During the synchronization idle time, preprocessed data with absolute timestamps is independently uploaded to the subsequent data processing unit through the data transmission interface, and each sensor main control board completes the transmission in parallel. S5. Post-processing data stitching and integration: The post-processing data unit receives pre-processed data with absolute timestamps uploaded by all sensor main control boards, stitches the collected data of each sensor array according to the time dimension based on the absolute timestamps, restores the pressure distribution and pressure change process over time in the large-format detection area, and outputs complete large-format dynamic and static pressure detection data.

4. The high refresh rate sampling method for a large-format high refresh rate dynamic and static pressure sampling system according to claim 3, characterized in that: In step S1, the target control voltage of the voltage-controlled crystal oscillator The expression is as follows: ； in, ； ； In the formula, This indicates the current actual control voltage of the voltage-controlled crystal oscillator; This indicates the adjustment amount of the control voltage of the voltage-controlled crystal oscillator; This indicates the current actual average frequency error of the voltage-controlled crystal oscillator, and , This indicates that the voltage-controlled crystal oscillator is in The actual cumulative clock pulses within each PPS cycle This indicates that the voltage-controlled crystal oscillator is in Ideal cumulative clock pulse count within one PPS cycle; Indicates the target frequency error; This indicates the frequency error difference that needs to be corrected; This indicates the voltage-frequency sensitivity of the voltage-controlled crystal oscillator.

5. The high refresh rate sampling method for a large-format high refresh rate dynamic and static pressure sampling system according to claim 3, characterized in that: In step S1, if the satellite signal is interrupted, the stored reference data of voltage-controlled crystal oscillator temperature and control voltage are automatically retrieved; the temperature of the voltage-controlled crystal oscillator is adjusted by the temperature controller, and the control voltage is adjusted synchronously to restore the temperature and pressure environment during calibration and maintain the clock output accuracy.

6. The high refresh rate sampling method of a large-format high refresh rate dynamic and static pressure sampling system according to claim 5, characterized in that: The formula for adjusting the temperature of a voltage-controlled crystal oscillator is as follows: ； in, ； In the formula, Indicates temperature regulation bias; This indicates the temperature reference data of the voltage-controlled crystal oscillator stored after calibration when the satellite signal is valid; This indicates the target operating temperature of the voltage-controlled crystal oscillator when the satellite signal is interrupted. This indicates the current operating temperature of the voltage-controlled crystal oscillator when the satellite signal is interrupted. The voltage adjustment formula is as follows: ； in, ； In the formula, This indicates the adjustment bias of the control voltage; This indicates the voltage-controlled crystal oscillator control voltage reference data stored after calibration when the satellite signal is valid; This indicates the current control voltage of the voltage-controlled crystal oscillator when the satellite signal is interrupted; This indicates the target control voltage of the voltage-controlled crystal oscillator when the satellite signal is interrupted.

7. The high refresh rate sampling method for a large-format high refresh rate dynamic and static pressure sampling system according to claim 5, characterized in that: In steps S2 and S3, the duration of the horizontal synchronization signal The calculation formula is as follows: ； In the formula, Indicates the number of columns in a single sensor array; This indicates the acquisition time of a single pressure sensor point; Interval time of field synchronization signal The calculation formula is as follows: ； In the formula, Indicates the number of rows in a single sensor array; Indicates the duration of synchronization idle time; The formula for calculating the synchronization idle time duration mentioned in step S4 is as follows: ； In the formula, This represents the total time it takes for a single sensor array to complete all row scans.

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