A pressure signal fitting method and apparatus

Abstract

The application provides a pressure signal fitting method and device, the method comprises: applying pressure to each sensing point in a pressure sensor, measuring the relationship between pressure and resistance of each sensing point, and integrating to obtain the pressure-resistance relationship; the pressure-resistance relationship is corrected through a numerical filtering algorithm, and the corrected pressure-resistance relationship is fitted to obtain an optimized pressure-resistance relationship; the switching of the voltage sensing circuit sensing points is carried out through an integrated analog electronic switch, the voltage of the stressed multiple array sensing points is measured; the resistance of the multiple array sensing points is calculated according to the measured voltage combined with the acquisition circuit; and the pressure of the multiple array sensing points is calculated through the optimized pressure-resistance relationship; based on the area of the stress area and the non-stress area of the multiple array sensing points, the actual stress of the multiple array sensing points is calculated through the relationship between force and pressure.

Description

Technical Field

[0001] This invention relates to the field of signal fitting technology, and more particularly to a method and apparatus for fitting pressure signals. Background Technology

[0002] Data fitting is a crucial step in sensor measurement systems, enabling the quantitative analysis of the sensor's physical signals. FSR (Pressure Distribution Detector) products measure pressure distribution, and their data fitting varies depending on the sensor used. Product datasheets from different manufacturers for FSR sensors include the following key information: the force range at the sensing point during normal operation and a table (curve) showing the force-resistance relationship at the sensing point. The force-resistance curve is shown below. Figure 1 As shown, the force-resistance relationship curve is obtained through operation in a specific environment. In actual operation, within the measurement range specified in the datasheet, the resistance value at the sensing point and the actual force generally follow the correspondence described in the sensor datasheet, but there may be inconsistencies between different sensing points. Therefore, FSR measurement sensors from different manufacturers have the following problems: potentially different measurement ranges, inconsistencies in the measurement sensing points, potential interference introduced into the measurement circuit, and different force display effects when the same circuit is connected to different pressure points. Theoretical derivation, numerical filtering, and result calibration are usually required to achieve higher measurement results.

[0003] Therefore, a pressure signal fitting scheme that can be used in actual operating environments is needed. Summary of the Invention

[0004] In view of this, embodiments of the present invention provide a pressure signal fitting method and apparatus to eliminate or improve one or more defects existing in the prior art.

[0005] One aspect of the present invention provides a pressure signal fitting method, the method comprising the following steps:

[0006] Based on each sensing point in the pressure acquisition device, pressure is applied to each sensing point by a force application device, the relationship between pressure and resistance at each sensing point under force is measured, and the relationship between pressure and resistance at each sensing point is integrated to obtain the pressure-resistance relationship;

[0007] Based on the integrated pressure-resistance relationship, the pressure-resistance relationship is corrected by a numerical filtering algorithm, and the corrected pressure-resistance relationship is fitted by a curve fitting formula to obtain an optimized pressure-resistance relationship.

[0008] By switching the sensing points of the voltage sensing circuit through an integrated analog electronic switch, the voltage of multiple array sensing points under force is measured respectively.

[0009] The resistance of the multiple array sensing points subjected to the force is calculated based on the measured voltage and the acquisition circuit.

[0010] The pressure of the multiple array sensing points is calculated based on the calculated resistance using the optimized pressure-resistance relationship.

[0011] Based on the area of ​​the force-bearing region and the non-force-bearing region of the multiple force-sensing points, the pressure of the multiple array sensing points is obtained by calculating the actual force of the multiple array sensing points through the relationship between force and pressure.

[0012] In some embodiments of the present invention, the method further includes: using drawing software to visualize the optimized pressure-resistance relationship by plotting points.

[0013] In some embodiments of the present invention, the step of measuring the voltage of the multiple array sensing points subjected to force includes:

[0014] The voltage of multiple array sensing points subjected to the force is measured by an on-chip integrated analog electronic switch or an off-chip digital-to-analog converter.

[0015] In some embodiments of the present invention, the method further includes: outputting the measured voltage through the conversion unit of a digital-to-analog converter.

[0016] In some embodiments of the present invention, the method further includes: appropriately increasing or decreasing the number of integrated analog electronic switches based on the number of rows and columns of the pressure sensor.

[0017] In some embodiments of the present invention, the method further includes: displaying the area where the force-applying device applies pressure to the array of sensing points using a heat map.

[0018] In some embodiments of the present invention, fitting the obtained modified pressure-resistance relationship using a curve fitting formula includes:

[0019] The corrected pressure-resistance relationship is fitted by selecting the appropriate curve fitting betweenness.

[0020] Another aspect of the present invention provides a pressure signal fitting device, which includes a processor and a memory, wherein the memory stores computer instructions, and the processor is used to execute the computer instructions stored in the memory. When the computer instructions are executed by the processor, the device implements the steps of the method described above.

[0021] The present invention also provides a computer-readable storage medium having a computer program stored thereon, characterized in that the program, when executed by a processor, implements the steps of the method described above.

[0022] The present invention provides a pressure signal fitting method and apparatus that can correct the measured pressure-resistance relationship through a numerical filtering algorithm, and fit the corrected pressure-resistance relationship according to a suitable curve fitting betweenness, thereby standardizing the signal fitting process and improving the accuracy of signal measurement; it can also switch the voltage of the sensing points of the measurement array by integrating an analog switch, realizing multi-channel signal switching and improving the efficiency of signal acquisition.

[0023] Additional advantages, objects, and features of the invention will be set forth in part in the description which follows, and will also become apparent in part to those skilled in the art upon studying the description, or may be learned by practice of the invention. The objects and other advantages of the invention can be realized and obtained by means of the structures specifically pointed out in the description and drawings.

[0024] Those skilled in the art will understand that the objectives and advantages achievable with the present invention are not limited to those specifically described above, and that the above and other objectives achievable with the present invention will become clearer from the following detailed description. Attached Figure Description

[0025] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, are not intended to limit the scope of the invention. In the drawings:

[0026] Figure 1 This is a pressure-resistance relationship curve measured by the manufacturer in this invention.

[0027] Figure 2 This is a schematic diagram of a pressure signal fitting method in one embodiment of the present invention.

[0028] Figure 3 This is a fitted pressure-resistance curve from one embodiment of the present invention.

[0029] Figure 4 This is a schematic diagram of the pinout of a digital-to-analog converter in one embodiment of the present invention.

[0030] Figure 5 This is a flowchart of the array sensing point voltage acquisition process in one embodiment of the present invention.

[0031] Figure 6 This is a schematic diagram of the force applied to the array sensing points in one embodiment of the present invention.

[0032] Figure 7 This is a force hotspot diagram of the array sensing points in one embodiment of the present invention.

[0033] Figure 8 This is a schematic diagram of the force-bearing area of ​​the array sensing points in one embodiment of the present invention. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the embodiments and accompanying drawings. Here, the illustrative embodiments and descriptions of this invention are used to explain the invention, but are not intended to limit the invention.

[0035] It should also be noted that, in order to avoid obscuring the invention with unnecessary details, only the structures and / or processing steps closely related to the solution according to the invention are shown in the accompanying drawings, while other details that are not closely related to the invention are omitted.

[0036] It should be emphasized that the term "including / comprises" as used herein refers to the presence of a feature, element, step, or component, but does not exclude the presence or addition of one or more other features, elements, steps, or components.

[0037] It should also be noted that, unless otherwise specified, the term "connection" in this article can refer not only to a direct connection, but also to an indirect connection involving an intermediary.

[0038] In the following description, embodiments of the invention will be illustrated with reference to the accompanying drawings. In the drawings, the same reference numerals represent the same or similar parts, or the same or similar steps.

[0039] To overcome the problems of inconsistent sensing point performance, different measurement ranges, and varying results in existing technologies, this invention proposes a pressure signal fitting method and apparatus. This method corrects the measured pressure-resistance relationship using a numerical filtering algorithm and fits the corrected pressure-resistance relationship based on a suitable curve fitting betweenness factor. This standardizes the signal fitting process and improves the accuracy of signal measurement. Furthermore, it enables multi-channel signal switching by integrating an analog switch to switch the voltage of the sensing points in the measurement array, thereby improving the efficiency of signal acquisition.

[0040] Figure 2 This invention provides a pressure signal fitting method in one embodiment, such as... Figure 1 As shown, the method includes the following steps:

[0041] Step S110: Based on each sensing point in the pressure acquisition device, pressure is applied to each sensing point through a force application device, the relationship between pressure and resistance of each sensing point under force is measured, and the relationship between pressure and resistance of each sensing point is integrated to obtain the pressure-resistance relationship.

[0042] In this step, pressure is applied to each sensing point in the pressure acquisition device using a force-applying device, and the pressure and resistance of each sensing point are measured separately. The pressure and resistance are then used to form a pressure-resistance relationship for each sensing point, and finally integrated to obtain the sum of the pressure-resistance relationships for all sensing points in the pressure acquisition device.

[0043] In one embodiment of the present invention, each force sensing point in the pressure acquisition device is equivalent to an adjustable resistor. The measured resistance value varies depending on the force applied to each sensing point, and the resistance value changes with the change in force. Therefore, the pressure-resistance relationships formed by each sensing point are different. These relationships are integrated to obtain the overall pressure-resistance relationship of the pressure acquisition device. The integration method includes, but is not limited to, weighted average summation or arithmetic average summation.

[0044] In one embodiment of the present invention, the pressure sensor used in the pressure acquisition device includes, but is not limited to, an FSR pressure sensor.

[0045] Step S130: Based on the integrated pressure-resistance relationship, the pressure-resistance relationship is corrected by a numerical filtering algorithm, and the corrected pressure-resistance relationship is fitted by a curve fitting formula to obtain an optimized pressure-resistance relationship.

[0046] In this step, based on the integrated pressure-resistance relationship, the integrated pressure-resistance relationship is corrected by a numerical filtering algorithm, and a suitable curve fitting betweenness is selected to fit the corrected pressure-resistance relationship using a curve fitting formula to obtain an optimized pressure-resistance relationship.

[0047] In one embodiment of the present invention, the modified pressure-resistance relationship is fitted using a curve fitting formula to obtain an optimized pressure-resistance relationship curve, as shown below. Figure 3 As shown in the figure, the horizontal axis (x) represents the magnitude of the force, in kilograms (kg), and the vertical axis (y) represents the conductivity (the reciprocal of the resistance) at the point where the force is applied. The curve fitting formula is shown in the figure:

[0048] y = 0.5537x 2 +0.7827x -0.0353;

[0049] in, Figure 3 The left side shows the specific pressure and resistance values. Since the pressure acquisition device's measurement system generally uses an integrated analog switch (MXU) for processing, it is necessary to appropriately select the curve fitting betweenness factor. The curve fitting betweenness factor cannot be too high. Depending on the selected betweenness factor, the curve fitting formula will change accordingly. Therefore, the above curve fitting formula is only an example, and this invention is not limited to it.

[0050] In one embodiment of the present invention, the optimized pressure-resistance relationship can be visualized using plotting software via a point-plotting method. For example, software such as Excel or MATLAB can be used to visualize the pressure-resistance relationship.

[0051] Step S150: The voltage sensing points of the voltage sensing circuit are switched by an integrated analog electronic switch, and the voltages of multiple array sensing points subjected to force are measured respectively.

[0052] In this step, the column sensing point and row sensing point circuits are switched by an integrated analog electronic switch, and the voltage of the column sensing point and row sensing point under force is measured respectively.

[0053] In one embodiment of the present invention, a digital-to-analog converter (DAC) is used to measure the voltage of multiple array sensing points subjected to force. However, the number of channels of the DAC is limited. When measuring multiple array sensing points, it is necessary to switch them using an analog electronic switch. In this embodiment of the present invention, the DAC used is a 74HC4051, and the pin diagram is shown below. Figure 4 As shown, its digital-to-analog converter includes: 8 input channels (A0-A7), 3 digital selection terminals (S0-S2), and 1 enable terminal. The device has one positive power supply terminal (VCC), one negative power supply terminal (VEE), one ground terminal (GND), and one common output terminal (A), with the common output terminal connected to an integrated analog electronic switch. During voltage measurement, the integrated analog electronic switch controls the digital selection terminals (S0-S2) to select which of the input terminals (A0-A7) should be connected to the common output terminal. Once one terminal is connected to the common output terminal, the signals on the other terminals are disconnected. This is how voltage measurement is performed.

[0054] In one embodiment of the present invention, the voltage measurement flowchart is as follows: Figure 5 As shown, the integrated analog electronic switch switches the sensing points to a row and supplies power. After the power supply is complete, it switches to the sensing points to a column and supplies power. After the signal stabilizes, the voltage values ​​of different columns in that row are read to complete the voltage measurement.

[0055] In one embodiment of the present invention, the voltage of multiple array sensing points subjected to force can be measured by an on-chip integrated analog electronic switch or an off-chip digital-to-analog converter.

[0056] In one embodiment of the present invention, the measured voltage value is output by the conversion unit of the data converter.

[0057] In one embodiment of the present invention, based on the diversity of integrated analog electronic switches in terms of type, number of channels and control methods, the present invention does not limit their model.

[0058] In one embodiment of the present invention, during actual operation, the number of integrated analog electronic switches can be appropriately increased or decreased according to the number of rows and columns of array sensing points in the actual pressure sensor, so that a digital-to-analog converter with fewer channels can complete the measurement of voltage at more array sensing points.

[0059] Step S170: Calculate the resistance of the multiple array sensing points under force based on the measured voltage and the acquisition circuit.

[0060] In this step, the resistance of multiple array sensing points under force is calculated by the acquisition circuit in the pressure acquisition device based on the voltage measured in step S150.

[0061] In one embodiment of the present invention, the acquisition circuit of the pressure acquisition device may include a programmable gain amplifier (PGA) or a series fixed resistor voltage divider. The measured voltage, combined with the settings of the acquisition circuit, is used to calculate the resistance values ​​of multiple array sensing points under force.

[0062] Step S190: The pressure of the multiple array sensing points is calculated based on the calculated resistance using the optimized pressure-resistance relationship.

[0063] In one embodiment of the invention, the pressure of multiple array sensing points is calculated based on the pressure-resistance relationship optimized in step S130 and the resistance value calculated in step S170.

[0064] Step S210: Based on the area of ​​the force-bearing region and the non-force-bearing region of the plurality of force-sensing points, the pressure of the plurality of array sensing points is obtained by calculating the actual force of the plurality of array sensing points through the relationship between force and pressure.

[0065] In this step, pressure is applied to the array sensing points, and the area of ​​the force-bearing and non-force-bearing areas of the sensing points is obtained based on the force on the array sensing points. The actual force on multiple array sensing points is calculated based on the pressure obtained in step S190 through the relationship between force and pressure.

[0066] In one embodiment of the present invention, pressure is applied over a large area to the array sensing points, and the force diagram is shown below. Figure 6 As shown, the circular area is the pressure sensing area, the white area is the non-pressure sensing point area, and the darker area is the force-receiving area (force application area).

[0067] In one embodiment of the present invention, pressure is applied to the pressure sensor by the palm of the hand, and the force display can be shown as a heat map on a host computer, such as... Figure 7 As shown, the white area represents the area under stress.

[0068] In one embodiment of the present invention, when applying pressure to a large area of ​​the array sensing points using a force-applying device, the force is generally uniformly applied. The array-type FSR can be evenly distributed among n measurement units, and the force-bearing area of ​​the array sensing points is as follows: Figure 8 As shown in the figure, each unit has 9 elements. Each element consists of a region P where force can be measured and a region U where force cannot be measured. Let the area of ​​region P be Sp and the area of ​​region U be Su. Based on the optimized pressure-resistance relationship and resistance value, the actual force F at each pressure point in region P is calculated. P The actual force on each measuring unit is calculated using the formulas for force and pressure, and the formula for the actual force satisfies:

[0069]

[0070] Based on the calculated actual force, when the force direction of each force sensing point is the same, the sum of all actual force values ​​results in the overall pressure; if the force directions are different, the force value of each sensing point is the frontal pressure.

[0071] Based on the pressure signal fitting method described above, in practical applications, it can be used to fit various resistive array pressure signals such as foot pressure distribution, hand grip pressure distribution, seat cushion pressure distribution, and backrest pressure distribution, and is compatible with common pressure distribution measurement sensors from different manufacturers.

[0072] Corresponding to the above method, the present invention also provides a pressure signal fitting device, which includes a computer device, the computer device including a processor and a memory, the memory storing computer instructions, the processor executing the computer instructions stored in the memory, and when the computer instructions are executed by the processor, the device performs the steps of the method as described above.

[0073] In summary, this invention proposes a pressure signal fitting method and apparatus that can correct the measured pressure-resistance relationship using a numerical filtering algorithm, and fit the corrected pressure-resistance relationship according to a suitable curve fitting betweenness factor. This standardizes the signal fitting process and improves the accuracy of signal measurement. Furthermore, it enables multi-channel signal switching by integrating an analog switch to switch the voltage of the sensing points of the measurement array, thereby improving the efficiency of signal acquisition.

[0074] This invention also provides a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the steps of the aforementioned edge computing server deployment method. The computer-readable storage medium can be a tangible storage medium, such as random access memory (RAM), main memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, floppy disks, hard disks, removable storage disks, CD-ROMs, or any other form of storage medium known in the art.

[0075] Those skilled in the art will understand that the exemplary components, systems, and methods described in conjunction with the embodiments disclosed herein can be implemented in hardware, software, or a combination of both. Whether implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this invention. When implemented in hardware, it can be, for example, electronic circuits, application-specific integrated circuits (ASICs), appropriate firmware, plug-ins, function cards, etc. When implemented in software, the elements of this invention are programs or code segments used to perform the desired tasks. The programs or code segments can be stored in a machine-readable medium or transmitted over a transmission medium or communication link via data signals carried in a carrier wave.

[0076] It should be clarified that the present invention is not limited to the specific configurations and processes described above and shown in the figures. For the sake of brevity, detailed descriptions of known methods are omitted here. In the above embodiments, several specific steps are described and shown as examples. However, the method process of the present invention is not limited to the specific steps described and shown. Those skilled in the art can make various changes, modifications, and additions, or change the order of steps, after understanding the spirit of the present invention.

[0077] In this invention, features described and / or illustrated for one embodiment may be used in the same or similar manner in one or more other embodiments, and / or combined with or in place of features of other embodiments.

[0078] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, various modifications and variations of the embodiments of the present invention are possible. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A pressure signal fitting method, characterized in that, The method includes the following steps: Based on each sensing point in the pressure acquisition device, pressure is applied to each sensing point by a force application device, the relationship between pressure and resistance at each sensing point under force is measured, and the relationship between pressure and resistance at each sensing point is integrated to obtain the pressure-resistance relationship; Based on the integrated pressure-resistance relationship, the pressure-resistance relationship is corrected by a numerical filtering algorithm, and the corrected pressure-resistance relationship is fitted by a curve fitting formula to obtain an optimized pressure-resistance relationship. By switching the sensing points of the voltage sensing circuit through an integrated analog electronic switch, the voltage of multiple array sensing points under force is measured respectively. The resistance of the multiple array sensing points subjected to the force is calculated based on the measured voltage and the acquisition circuit. The pressure of the multiple array sensing points is calculated based on the calculated resistance using the optimized pressure-resistance relationship. Based on the areas of the force-bearing and non-force-bearing regions of multiple force-sensing points, the pressure of the multiple array sensing points is calculated using the relationship between force and pressure to obtain the actual force of the multiple array sensing points. The array sensing points include multiple measuring units, each measuring unit including a region where force can be measured and a region where force cannot be measured. The actual force of each region where force can be measured is calculated based on the optimized pressure-resistance relationship and resistance. The actual force of each measuring unit is calculated according to the following formula, thereby obtaining the actual force of the corresponding array sensing point: in, This indicates the actual force acting on the measuring unit. This represents the actual force in the area where force can be measured. This represents the area of ​​the region where force can be measured. This represents the area of ​​the region where the force cannot be measured.

2. The method according to claim 1, characterized in that, The method also includes: using drawing software to visualize the optimized pressure-resistance relationship through a point plotting method.

3. The method according to claim 1, characterized in that, The measurement of the voltage at multiple array sensing points under force includes: The voltage of multiple array sensing points subjected to the force is measured by an on-chip integrated analog electronic switch or an off-chip digital-to-analog converter.

4. The method according to claim 3, characterized in that, The method further includes: outputting the measured voltage through the conversion unit of a digital-to-analog converter.

5. The method according to claim 1, characterized in that, The method further includes: appropriately increasing or decreasing the number of integrated analog electronic switches based on the number of rows and columns of pressure sensors in the pressure acquisition device.

6. The method according to claim 1, characterized in that, The method further includes: displaying the area where the force-applying device applies pressure to the array of sensing points using a heat map.

7. The method according to claim 1, characterized in that, The step of fitting the obtained modified pressure-resistance relationship using a curve fitting formula includes: The corrected pressure-resistance relationship is fitted by selecting the appropriate curve fitting betweenness.

8. A pressure signal fitting device, comprising a processor and a memory, characterized in that, The memory stores computer instructions, and the processor executes the computer instructions stored in the memory. When the computer instructions are executed by the processor, the device implements the steps of the method as described in any one of claims 1 to 7.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the steps of the method as described in any one of claims 1 to 7.

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