Absolute pressure transmitter testing method based on curve boundary
By introducing qualitative and quantitative judgment methods for curve boundaries in the testing of absolute pressure transmitters, the problem of the inability to assess continuous output characteristics in existing technologies has been solved, and more accurate test results have been achieved.
Patent Information
- Application Number
- CN202510923055.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-04
- Publication Date
- 2025-11-04
AI Technical Summary
In the existing technology, the testing methods for absolute pressure transmitters can only detect the output accuracy at discrete points, and cannot assess the continuous output characteristics within the measurement range, resulting in inaccurate testing.
A test method based on curve boundaries is adopted. By establishing the maximum error curve, the minimum error curve, and the actual output curve in the same coordinate system, and combining qualitative and quantitative judgments, it is determined whether the output of the absolute pressure transmitter meets the requirements.
It improves the testing accuracy of absolute pressure transmitters, enabling the determination of whether their output trend is stable and whether their accuracy meets the standards within the measurement range.
Smart Images
Figure CN120890604A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the field of avionics, in particular to a curve boundary based absolute pressure transmitter testing method. BACKGROUND
[0002] In the absolute pressure transmitter inspection, the input and output characteristics and indexes of the absolute pressure transmitter are often judged according to some discrete experimental test points. Through this method, only the output accuracy of the absolute pressure transmitter at these characteristic points can be detected, and the continuous output characteristics in the measurement range cannot be examined. SUMMARY
[0003] Therefore, the present application provides a curve boundary based absolute pressure transmitter testing method, which solves the problems in the prior art and improves the testing accuracy.
[0004] The curve boundary based absolute pressure transmitter testing method provided by the present application adopts the following technical scheme: A curve boundary based absolute pressure transmitter testing method comprises the following steps: establishing an error maximum value curve and an error minimum value curve under a first input condition of the absolute pressure transmitter in the same coordinate system; establishing an actual output curve of the measured absolute pressure transmitter under the first input condition in the coordinate system of the error maximum value curve and the error minimum value curve; judging whether the output of the measured absolute pressure transmitter meets the requirements according to the positional relationship of the three curves; If the actual output curve is between the error maximum value curve and the error minimum value curve, it is considered that the output of the measured absolute pressure transmitter meets the requirements.
[0005] Optionally, in the process of judging whether the output of the measured absolute pressure transmitter meets the requirements: qualitative judgment is performed first, and then quantitative judgment is performed after the qualitative judgment; the qualitative judgment method is to observe the positional relationship of the three curves by naked eyes; the quantitative judgment is to judge whether the actual output curve exceeds the range of the two curves by calculating the parameters of the three curves.
[0006] Optionally, a line segment is obtained by connecting two points, one of which is the output error upper limit when the input is the upper limit of the measured pressure, and the other of which is the output error lower limit when the input is the lower limit of the measured pressure, the slope of the first line segment is Kmax, and the intercept of the first line segment is Bmin; a second line segment is obtained by connecting two points, one of which is the output error lower limit when the input is the upper limit of the measured pressure, and the other of which is the output error upper limit when the input is the lower limit of the measured pressure, the slope of the second line segment is Kmin, and the intercept of the first line segment is Bmax; the slope of the error minimum value curve is K; The step of quantitative judgment comprises: When the slope ks of the actual output curve is greater than K and less than Kmax, and the actual output curve satisfies B1>bs>Bmin, it is judged that the output of the sensor meets the requirements, wherein bs is the intercept of the actual output curve, and B1 is the intercept of a straight line with a slope of ks passing through a point corresponding to the maximum output value when the input is the upper limit of the pressure to be measured.
[0007] Optionally, the step of quantitative judgment further comprises: When the slope ks of the actual output curve is greater than Kmin and less than K, and the actual output curve satisfies Bmax>bs>B2, it is judged that the output of the sensor meets the requirements, wherein B2 is the intercept of a straight line with a slope of ks passing through a point corresponding to the minimum output value when the input is the upper limit of the pressure to be measured.
[0008] Optionally, the step of quantitative judgment further comprises: when the slope ks of the actual output curve is equal to K, and Bmax≥bs≥Bmin, it is judged that the output of the sensor meets the requirements.
[0009] Optionally, in the process of drawing the actual output curve, the slope and the intercept of the actual output curve are obtained by the least square method according to the actual input-output points, and the actual input-output curve is fitted.
[0010] Optionally, the error maximum value curve, the error minimum value curve and the actual output curve are drawn in different colors.
[0011] In summary, the present application includes the following beneficial technical effects: Through the analysis of the input-output characteristic curve of a certain type of absolute pressure transmitter, through the qualitative and quantitative method, it can be judged whether the output trend of the linear sensor in its measurement range is stable and the output precision is up to standard, so as to get rid of the shortcomings of insufficient and non-intuitive feature point test, and improve the accuracy of the test. BRIEF DESCRIPTION OF DRAWINGS
[0012] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed in the embodiments will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creating any creative labor.
[0013] Figure 1 The schematic diagram of the error maximum value curve, the error minimum value curve and the actual output curve in the embodiments of the present application; Figure 2 The input-output schematic diagram of the absolute pressure transmitter in the limit case in the embodiments of the present application. DETAILED DESCRIPTION
[0014] The embodiments of the present application will be described in detail below with reference to the drawings.
[0015] The above examples are merely illustrative of the embodiments of the present application, and non-limiting. Numerous modifications and adaptations thereof will be apparent to those skilled in the art without departing from the spirit and scope of the present application. Therefore, the scope of the present application is not intended to be limited to the above examples, but is only limited to the scope of the following claims.
[0016] It is to be understood that the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. It should be apparent that aspects of the application described herein can be implemented in any of numerous ways as the application is not limited to any particular manner of implementation. Examples of specific implementations are provided for illustrative purposes only.
[0017] It is also to be understood that the following description is only illustrative of the aspects of the present application and that no limitation of the scope of the present application is intended by the description. It is further understood that the aspects of the present application can be used in any combination and that the description of the aspects of the present application is not limited to any particular combination.
[0018] In addition, in the following description, numerous specific details are provided for a thorough understanding of the examples. One skilled in the relevant art will recognize, however, that the aspects described herein can be practiced without one or more of these specific details.
[0019] The embodiments of the present application provide a curve boundary based absolute pressure transmitter testing method.
[0020] In the sensor product test, the relationship between input and output can be obtained according to the experimental data, that is, the calibration curve between input and output. For linear sensors, the input-output characteristic curve is close to a straight line. Taking a certain type of absolute pressure transmitter as an example: the absolute pressure transmitter is used to measure the absolute pressure of the measured environment, and is widely used in aerospace, medical treatment, automation equipment and other fields. Its core is to use the Wheatstone strain bridge principle. When the sensor sensitive part is not subjected to external pressure, the bridge is in a balanced state, which is called zero position. When the sensitive part is subjected to pressure, the bridge loses balance and outputs a voltage signal. The bridge output voltage signal is proportional to the pressure difference acting on the silicon wafer, and the overall output shows a linear trend. This paper takes the absolute pressure transmitter as an example for discussion.
[0021] As shown in Figure 1 and Figure 2 , a curve boundary-based absolute pressure transmitter test method includes the following steps: In the same coordinate system, the error maximum curve and the error minimum curve under the first input condition of the absolute pressure transmitter are established. In the coordinate system of the error maximum curve and the error minimum curve, the actual output curve of the measured absolute pressure transmitter under the first input condition is established. According to the positional relationship of the three curves, it is judged whether the output of the measured absolute pressure transmitter meets the requirements.
[0022] If the actual output curve is between the error maximum curve and the error minimum curve, it is considered that the output of the measured absolute pressure transmitter meets the requirements.
[0023] The error maximum curve, the error minimum curve and the actual output curve are drawn in different colors. In the embodiment of the application, the error maximum curve is red, the error minimum curve is blue, and the actual output curve is blue. In the process of drawing the actual output curve, the slope and intercept of the actual output curve are obtained by the least square method according to the actual input-output points, and the actual input-output curve is fitted.
[0024] In theory, under the condition that the absolute pressure transmitter is qualified, the actual test output value should be between the upper and lower limits of the error, so the output curve should be between the red and green curves in Figure 1 .
[0025] Ideally, the actual output curve of the product should infinitely approach the blue line in Figure 1 , which means that the actual output value of the product infinitely approaches the theoretical output value.
[0026] In the process of judging whether the output of the measured absolute pressure transmitter meets the requirements: first qualitative judgment, and then quantitative judgment after qualitative judgment; the qualitative judgment method is to observe the position relationship of the three curves by naked eyes; the quantitative judgment is to judge whether the actual output curve exceeds the range of the two curves by calculating the parameters of the three curves.
[0027] The line connecting the two points of the error upper limit when the input is the upper limit of the measured pressure and the error lower limit when the input is the lower limit of the measured pressure is taken as the first line segment, the slope of the first line segment is Kmax, and the intercept of the first line segment is Bmin. The line connecting the two points of the error lower limit when the input is the upper limit of the measured pressure and the error upper limit when the input is the lower limit of the measured pressure is taken as the second line segment, the slope of the second line segment is Kmin, and the intercept of the first line segment is Bmax. Figure 2 The first line segment is represented by the medium purple line segment, and the second line segment is represented by the yellow line segment. The slope of the error minimum curve is defined as K, the slope of the actual output curve is defined as ks, and the intercept of the actual output curve is defined as bs.
[0028] The steps of quantitative judgment include: When the slope ks of the actual output curve is greater than K and less than Kmax, and the actual output curve satisfies B1>bs>Bmin, it is judged that the output of the sensor meets the requirements, wherein B1 is the intercept of the straight line passing through the point corresponding to the maximum output value when the input is the upper limit of the measured pressure and having a slope of ks.
[0029] When the slope ks of the actual output curve is greater than Kmin and less than K, and the actual output curve satisfies Bmax>bs>B2, it is judged that the output of the sensor meets the requirements, wherein B2 is the intercept of the straight line passing through the point corresponding to the minimum output value when the input is the upper limit of the measured pressure and having a slope of ks.
[0030] The steps of quantitative judgment further include: when the slope ks of the actual output curve is equal to K, and Bmax≥bs≥Bmin, it is judged that the output of the sensor meets the requirements.
[0031] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto, any changes or replacements easily thought of by those skilled in the art within the technical range disclosed in the present application should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.
Claims
1. A test method for absolute pressure transmitters based on curved boundaries, characterized in that, Includes the following steps: Establish the maximum and minimum error curves of the absolute pressure transmitter under the first input condition in the same coordinate system; Establish the actual output curve of the measured absolute pressure transmitter under the first input condition in the coordinate system of the error maximum and error minimum curves; Based on the positional relationship of the three curves, determine whether the output of the absolute pressure transmitter under test meets the requirements; If the actual output curve lies between the maximum and minimum error curves, the output of the measured absolute pressure transmitter is considered to meet the requirements.
2. The method for testing absolute pressure transmitters based on curved boundaries according to claim 1, characterized in that, In the process of determining whether the output of the absolute pressure transmitter under test meets the requirements: First, make a qualitative judgment, and then make a quantitative judgment based on the qualitative judgment. The qualitative judgment method is to visually observe the positional relationship of the three curves; Quantitative judgment is made by calculating the parameters of three curves to determine whether the actual output curve exceeds the range of two curves.
3. The method for testing absolute pressure transmitters based on curved boundaries according to claim 1, characterized in that, The first line segment is the line connecting the two points where the output is the upper limit of the measured pressure and the output is the lower limit of the error when the input is the lower limit of the measured pressure. The slope of the first line segment is Kmax and the intercept of the first line segment is Bmin. The second line segment is defined by connecting the two points where the output is the lower limit of error when the input is the upper limit of the measured pressure and the output is the upper limit of error when the input is the lower limit of the measured pressure. The slope of the second line segment is Kmin, and the intercept of the first line segment is Bmax. The slope of the error minimum curve is K; The steps for quantitative judgment include: When the slope ks of the actual output curve is greater than K and less than Kmax, and the actual output curve satisfies B1>bs>Bmin, the sensor output is judged to meet the requirements. Here, bs is the intercept of the actual output curve, and B1 is the intercept of the straight line with a slope of ks that passes through the point corresponding to the maximum output value when the input is the upper limit of the pressure to be measured.
4. The method for testing absolute pressure transmitters based on curved boundaries according to claim 3, characterized in that, The quantitative judgment process also includes: When the slope of the actual output curve ks is greater than Kmin and less than K, and the actual output curve satisfies Bmax>bs>B2, the sensor output is judged to meet the requirements. Here, B2 is the intercept of the straight line that passes through the point corresponding to the minimum output value when the input is the upper limit of the pressure to be measured and has a slope of ks.
5. The method for testing absolute pressure transmitters based on curved boundaries according to claim 3, characterized in that, The quantitative judgment steps also include: when the slope ks of the actual output curve is equal to K, and Bmax≥bs≥Bmin, it can be determined that the sensor output meets the requirements.
6. The method for testing absolute pressure transmitters based on curved boundaries according to claim 3, characterized in that, The process of plotting the actual output curve involves using the least squares method to calculate the slope and intercept of the actual output curve based on the actual input and output points, and then fitting the actual input and output curve.
7. The method for testing absolute pressure transmitters based on curved boundaries according to claim 1, characterized in that, The maximum error curve, the minimum error curve, and the actual output curve are drawn using different colors.