A multi-acceleration sensor parallel calibration system and calibration method

Abstract

The present invention discloses a multi-acceleration sensor parallel calibration system and calibration method, wherein the system comprises: a base plate, an elastic element, an exciter and a standard plate; the base plate and the standard plate are connected by the elastic element, the exciter is installed on the base plate and located between the base plate and the standard plate, the output end of the exciter is connected to the standard plate, and two or more mounting positions are provided on the side of the standard plate facing away from the base plate, and the mounting positions are used to mount standard acceleration sensors or acceleration sensors to be calibrated. The system of the present invention can simultaneously realize batch calibration and measurement of two or more acceleration sensors to be calibrated, and the calibration efficiency is higher.

Description

Technical Field

[0001] The invention belongs to the technical field of accelerometer measurement and calibration, and in particular relates to a multi-acceleration sensor parallel calibration system and calibration method. Background Art

[0002] In order to ensure the consistency of the measured parameters, the measuring instruments need to be measured according to the verification procedures or calibration specifications to ensure the use status of the measuring instruments. Accelerometers are used to evaluate the comfort of living, the ability of equipment to transmit externally, and the performance of vibration reduction and isolation devices, and are assessed by collecting and normalizing the acceleration level. Accelerometers have many applications, and the number of accelerometers used for each collection is also large. If the accelerometer needs to be measured once a year according to the verification procedures or calibration specifications, and during major tests or a measurement cycle, the equipment users also need to conduct periodic inspections to ensure the performance status of the accelerometer. The main measurement parameter in the measurement of accelerometers is the measurement of sensitivity, and the methods used are comparison method and absolute method. At present, the comparison method is widely used by metrological technical institutions. This method is to rigidly install the accelerometer to be tested and the reference standard accelerometer back to back at the center of the vibration table, or coaxially install it with the reference standard accelerometer installed in the vibration table, or coaxially install it with the reference standard accelerometer in the additional fixing device on the vibration table of the device, and finally perform measurement calibration.

[0003] However, the common acceleration sensor calibration system calibrates a single acceleration sensor. Each acceleration sensor needs to measure multiple frequency points. The calibration of one acceleration sensor takes a long time. When there are multiple sensors that need to be calibrated, the total time required is very long. It is time-consuming and laborious to disassemble each acceleration sensor. Therefore, the problem with the existing technology is that it is difficult to efficiently calibrate multiple acceleration sensors and cannot achieve batch calibration. Summary of the invention

[0004] In view of the above problems, the present invention proposes a multi-acceleration sensor parallel calibration system and calibration method, which can simultaneously realize batch calibration measurement of two or more acceleration sensors to be calibrated, and the calibration efficiency is higher.

[0005] In the first aspect, the present application provides the following technical solution through an embodiment:

[0006] A multi-acceleration sensor parallel calibration system comprises: a base plate, an elastic element, an exciter and a standard plate; the base plate and the standard plate are connected via the elastic element, the exciter is mounted on the base plate and located between the base plate and the standard plate, the output end of the exciter is connected to the standard plate, and two or more mounting positions are arranged on a side of the standard plate facing away from the base plate, and the mounting positions are used to mount standard acceleration sensors or acceleration sensors to be calibrated.

[0007] Optionally, the standard plate is a rigid plate, and the first-order natural frequency of the standard plate is greater than 5 kHz.

[0008] Optionally, the connection position between the exciter and the standard plate is located at the center of the standard plate.

[0009] Optionally, it further includes: a standard acceleration sensor, wherein the standard acceleration sensor is installed on a side of the standard plate facing the base plate.

[0010] Optionally, there are two or more standard acceleration sensors installed on the side of the standard plate facing the base plate; and the two or more standard acceleration sensors are evenly distributed on the standard plate.

[0011] Optionally, the mounting positions are evenly distributed on a side of the standard plate facing away from the base plate.

[0012] Optionally, the elastic element, the base plate and the standard plate form a support structure, and the natural frequency of the support structure is less than 1 / 10 of the lowest calibration frequency of the acceleration sensor to be calibrated.

[0013] Optionally, it further includes: an exciting rod, the exciter and the standard plate are connected to two ends of the exciting rod.

[0014] Optionally, it further includes: a force sensor, and the excitation rod is connected to the standard plate through the force sensor.

[0015] In the second aspect, based on the same inventive concept, the present application provides the following technical solution through an embodiment:

[0016] A method for parallel calibration of multiple acceleration sensors, applied to any system described in the first aspect above, the method comprising:

[0017] Installing standard acceleration sensors at all the above mentioned mounting positions;

[0018] The exciter is started to excite the standard plate to obtain a first transfer function and a first sensitivity of each standard acceleration sensor; the first transfer function represents a parameter value of the standard acceleration sensor in response to the corresponding excitation, and the first sensitivity represents a relationship between a signal change of the standard acceleration sensor and a measured acceleration;

[0019] replacing the standard acceleration sensor installed at the installation position with the acceleration sensor to be calibrated;

[0020] Starting the exciter to perform the same excitation on the standard plate to obtain a second transfer function of each acceleration sensor to be calibrated; the second transfer function represents a parameter value of the acceleration sensor to be calibrated in response to the corresponding excitation;

[0021] The acceleration sensor to be calibrated is calibrated according to the first transfer function, the first sensitivity and the second transfer function of the target installation position to obtain a second sensitivity of the target installation position; wherein the target installation position is any one of all the installation positions, and the second sensitivity represents a change relationship between a signal change of the acceleration sensor to be calibrated and a measured acceleration.

[0022] In a multi-acceleration sensor parallel calibration system provided in an embodiment of the present invention, since the base plate and the standard plate are connected by an elastic element, the influence of the weight of the accessories of the standard plate on the calibration can be eliminated; further, the exciter is installed on the base plate and is located between the base plate and the standard plate, and the output end of the exciter is connected to the standard plate, so that the exciter can be used to generate excitations of different frequencies to calibrate multiple frequency points; two or more mounting positions are provided on the side of the standard plate facing away from the base plate, and the mounting positions are used to install standard acceleration sensors or acceleration sensors to be calibrated. The system itself can be verified by two or more mounting positions, making the calibration more accurate, and batch calibration and measurement of two or more acceleration sensors to be calibrated can be achieved simultaneously, and the calibration efficiency is higher.

[0023] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented according to the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0025] Figure 1 A schematic structural diagram of a multi-acceleration sensor parallel calibration system provided by a preferred embodiment of the present invention is shown;

[0026] Figure 2 A schematic diagram of the structure of a standard plate in a preferred embodiment of the present invention is shown;

[0027] Figure 3 A flow chart of a method for parallel calibration of multiple acceleration sensors provided by a preferred embodiment of the present invention is shown.

[0028] Figure markings: 100 - parallel calibration system for multiple acceleration sensors; 1 - base plate; 2 - elastic element; 3 - standard acceleration sensor; 4 - standard plate; 5 - mounting position; 6 - acceleration sensor to be calibrated; 7 - exciting rod; 8 - force sensor; 9 - embedded cable; 10 - main cable; 11 - panel centralized cable; 12 - data acquisition instrument; 13 - communication cable; 14 - host computer; 15 - exciter cable, 16 - force sensor cable; 17 - exciter. DETAILED DESCRIPTION

[0029] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0030] Example

[0031] See also Figure 1 , Figure 1 The schematic diagram of the structure of a multi-acceleration sensor parallel calibration system 100 provided in this embodiment is shown. The calibration system comprises: a base plate 1 , an elastic element 2 , an exciter 17 and a standard plate 4 .

[0032] Specifically, the base plate 1 and the standard plate 4 are connected via an elastic element 2, the exciter 17 is installed on the base plate 1 and is located between the base plate 1 and the standard plate 4, the output end of the exciter 17 is connected to the standard plate 4, and a mounting position 5 is provided on the side of the standard plate 4 facing away from the base plate 1, and the mounting position 5 is used to install a standard acceleration sensor 3 or an acceleration sensor to be calibrated 6.

[0033] The bottom plate 1 is used as a carrier to install the elastic element 2 and the exciter 17. The bottom plate 1 may be provided with fixing buckles or threaded holes for fixing the elastic element 2 and the exciter 17.

[0034] The elastic element 2 is used to provide elastic support to support the standard plate 4 and reduce the influence of the additional weight of the standard plate 4 on the calibration result. The elastic element 2 in this embodiment should be soft enough to ensure that the standard plate 4 is not affected by the preload when the exciter 17 excites the standard plate 4, and the standard plate 4 can move freely without jamming. Specifically, the elastic element 2, the base plate 1 and the standard plate 4 form a support structure, and the natural frequency of the support structure should be less than 1 / 10 of the lowest calibration frequency of the acceleration sensor 6 to be calibrated. The natural frequency of the support structure can be expressed as Where W n is the natural frequency of the supporting structure, K is the stiffness coefficient of the elastic element 2, and M is the mass of the load borne by the elastic element 2.

[0035] The elastic element 2 may be a metal elastic element 2 or a non-metal elastic element 2; for example, a metal spring, a rubber shock absorber, and the like.

[0036] The standard plate 4 is installed with the standard acceleration sensor 3 and the acceleration sensor to be calibrated 6. The connection relationship between the standard plate 4 and the exciter 17 and the elastic element 2 can be a modular detachable connection, for example, connected by a snap mechanism, bolts and / or screws. When in use, multiple standard plates 4 can be used for replacement to ensure a high correction efficiency. The connection position between the exciter 17 and the standard plate 4 should be located at the center of the lower surface of the standard plate 4. At the same time, the standard plate 4 should be a rigid plate, and the first-order natural frequency of the standard plate 4 should be greater than 5kHz, so that when the standard plate 4 is excited, the standard plate 4 can better transmit the applied excitation. Among them, the lower surface of the standard plate 4 is the side facing the base plate 1.

[0037] There should be two or more mounting positions 5 set on the standard plate 4, so that multiple acceleration sensors 6 to be calibrated can be calibrated at the same time. Specifically, the mounting positions 5 can be evenly distributed on the side of the standard plate 4 facing away from the base plate 1, and the standard acceleration sensor 3 and the acceleration sensor 6 to be calibrated can be connected to the mounting positions 5 by screws. For example, the mounting positions 5 are evenly distributed in an m×n array, where m and n are m rows and n columns respectively; Figure 2 , showing a uniform array distribution of mounting positions 56×6. This ensures that after the sensor to be calibrated is installed at the mounting position 5, the mass distribution of the standard plate 4 is uniform, avoiding affecting the calibration result.

[0038] Furthermore, a standard acceleration sensor 3 can be set on the lower surface of the standard plate 4. The standard acceleration sensor 3 on the lower surface of the standard plate 4 and the standard acceleration sensor 3 installed on the mounting position 5 on the upper surface of the standard plate 4 can be used to inspect the standard plate 4 to determine whether there is an error or deviation in the excitation transmitted by the standard plate 4. This ensures that the final calibration result of the acceleration sensor 6 to be calibrated is credible. The number of standard acceleration sensors 3 set on the lower surface of the standard plate 4 can be two or more, and the two or more standard acceleration sensors 3 are evenly distributed on the standard plate 4. The data between the two or more standard acceleration sensors 3 can verify each other, and at the same time, the mass distribution of the standard plate 4 is uniform. In a preferred solution, the standard acceleration sensor 3 on the lower surface of the standard plate 4 should be directly opposite to a mounting position 5 on the upper surface of the standard plate 4.

[0039] Furthermore, the exciter 17 can be connected to the center of the lower surface of the standard plate 4 through an excitation rod 7, and the excitation rod 7 should be a rigid rod structure. The end of the excitation rod 7 can be connected to the standard plate 4 through a force sensor 8, and the relevant data of the excitation force generated can be read through the force sensor 8 when the exciter 17 is excited.

[0040] In this embodiment, in order to facilitate data collection and calculation, a host computer 14 and a data acquisition instrument 12 can be set up. The host computer 14 can be connected to the data acquisition instrument 12 through a communication cable 13. The installation position 5 and the standard acceleration sensor 3 can lead out the embedded cable 9 and connect a main cable 10 to transmit the data to the data acquisition instrument 12. A panel centralized cable 11 can be set on the data acquisition instrument 12 to transmit the data collected by the installation position 5 and the standard acceleration sensor 3 to the data acquisition instrument 12 respectively. The embedded cable 9 is a cable embedded in the standard board 4. The force sensor 8 can be connected to the data acquisition instrument 12 through the force sensor cable 16, and the exciter 17 can be connected to the data acquisition instrument 12 through the exciter cable 15. The data acquisition instrument 12 uploads the data to the host computer 14 through the communication cable 13 for processing and calculation, so as to realize automatic correction calculation.

[0041] The above-mentioned embedded cable 9 is a cable that matches the connector of the acceleration sensor to be calibrated, fixed on the standard board 4, and the number is consistent with the number of the acceleration sensors 6 to be calibrated. The host computer 14 is a computer installed with matching acceleration sensor metrology calibration analysis software, in which the analysis software can realize the calculation and processing of the collected data. The embedded cable 9, the main cable 10, and the panel centralized cable 11 can all be made into integrated cables, and the connectors are plug-in type to realize modular installation and connection. The data acquisition instrument 12 can collect the signals transmitted by the standard acceleration sensor 3, the acceleration sensor to be calibrated 6 and the force sensor 8, and has a multi-excitation signal output function. The number of channels of the acquisition instrument is greater than the number of acceleration sensors to be calibrated.

[0042] In a multi-acceleration sensor parallel calibration system 100 provided in this embodiment, since the base plate 1 and the standard plate 4 are connected by the elastic element 2, the influence of the accessory weight of the standard plate 4 on the calibration can be eliminated; further, the exciter 17 is installed on the base plate 1 and is located between the base plate 1 and the standard plate 4, and the output end of the exciter 17 is connected to the standard plate 4, so that the exciter 17 can be used to generate excitations of different frequencies to calibrate multiple frequency points; two or more mounting positions 5 are provided on the side of the standard plate 4 facing away from the base plate 1, and the mounting positions 5 are used to install standard acceleration sensors 3 or acceleration sensors to be calibrated 6. The system itself can be verified by two or more mounting positions 5, making the calibration more accurate, and batch calibration measurement of two or more acceleration sensors to be calibrated 6 can be achieved simultaneously, and the calibration efficiency is higher.

[0043] See also Figure 3 In this embodiment, a multi-acceleration sensor parallel calibration method is also provided, which is applied to the multi-acceleration sensor parallel calibration system mentioned above, and the method includes:

[0044] Step S10: Install standard acceleration sensors on all the installation positions.

[0045] Step S20: Start the exciter to excite the standard plate to obtain a first transfer function and a first sensitivity of each standard acceleration sensor; the first transfer function represents a parameter value of the standard acceleration sensor in response to the corresponding excitation, and the first sensitivity represents a relationship between a signal change of the standard acceleration sensor and a measured acceleration.

[0046] In steps S10-S20, the first transfer function and the first sensitivity can be received, recorded and saved by the host computer. Specifically, the first transfer function can be expressed as H1=F / X1, where F is the parameter value of the force sensor during the current excitation, and X1 represents the magnitude of the standard acceleration sensor's response to the excitation. In other embodiments, if the force sensor has low accuracy, the first transfer function can be replaced by X1 alone. The first sensitivity is the sensitivity used as a standard reference. Furthermore, the first transfer function of the standard acceleration sensor on the lower surface of the standard plate can be compared and verified with the first transfer function of the standard acceleration sensor on the upper surface of the standard plate to determine the accuracy of the multi-acceleration sensor parallel calibration system. For example, if the first transfer functions of the standard acceleration sensors on the lower surface and the upper surface of the standard plate are the same or the difference is within an acceptable range, it is determined that the standard plate and the elastic element of the multi-acceleration sensor parallel calibration system are reliable.

[0047] Step S30: replacing the standard acceleration sensor installed at the installation position with the acceleration sensor to be calibrated.

[0048] In step S30, all standard acceleration sensors on the panel of the standard board are removed, and then the acceleration sensor to be calibrated is installed. If there are redundant installation positions, standard acceleration sensors of the same mass are used to replace them, ensuring that the mass of the entire standard board and the entire spring system remains unchanged, avoiding calibration errors caused by mass changes.

[0049] Step S40: starting the exciter to perform the same excitation on the standard plate to obtain a second transfer function of each acceleration sensor to be calibrated; the second transfer function represents a parameter value of the acceleration sensor to be calibrated in response to the corresponding excitation.

[0050] In step S40, the excitation parameters such as frequency and amplitude of the excitation generated by the exciter are the same as those of the excitation generated by the exciter in step S30. Similarly, the host computer is used to receive and store the data generated after this excitation. Specifically, the second transfer function can be expressed as H2=F / X2, where F is the parameter value of the force sensor during the current excitation, and X2 represents the magnitude of the excitation response of the acceleration sensor to be calibrated at the current installation position. In other embodiments, if the force sensor has low accuracy, the first transfer function can be represented by only X2.

[0051] Furthermore, the first transfer function and the second transfer function values ​​respectively collected by the same standard acceleration sensor on the lower surface and the upper surface of the standard plate after two excitations by the exciter can be compared to determine whether the exciter is reliable. For example, if the first transfer function and the second transfer function respectively generated by the same standard acceleration sensor in the two excitation processes are the same or the difference is within an acceptable range, it is determined that the standard plate and the elastic element of the multi-acceleration sensor parallel calibration system are both reliable.

[0052] Step S50: calibrating the acceleration sensor to be calibrated according to the first transfer function, the first sensitivity and the second transfer function of the target installation position to obtain a second sensitivity of the target installation position; wherein the target installation position is any one of all the installation positions, and the second sensitivity represents the relationship between the signal change of the acceleration sensor to be calibrated and the measured acceleration.

[0053] In step S50, the second sensitivity corresponding to each installation position can be expressed as S1 is the first sensitivity of the target installation position, that is, the sensitivity of the standard acceleration sensor installed at the target installation position, and S2 is the second sensitivity of the target installation position, that is, the sensitivity of the acceleration sensor to be calibrated installed at the target installation position.

[0054] After step S50, steps S10-S50 are repeated in sequence by using an exciter with different frequencies to perform excitation, thereby achieving metrological calibration of the acceleration sensor to be calibrated at different frequency points.

[0055] In the multi-acceleration sensor parallel calibration method provided in this embodiment, multiple acceleration sensors to be calibrated can be calibrated simultaneously with high calibration accuracy.

[0056] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the invented product is usually placed when in use, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0057] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0058] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A multi-acceleration sensor parallel calibration method is applied to a multi-acceleration sensor parallel calibration system, the system comprising: Base plate, elastic element, exciter and standard plate; The base plate and the standard plate are connected via the elastic element, the exciter is mounted on the base plate and located between the base plate and the standard plate, the output end of the exciter is connected to the standard plate, the upper and lower surfaces of the standard plate are respectively provided with two or more mounting positions, the mounting positions are used to mount a standard acceleration sensor or an acceleration sensor to be calibrated, and the method comprises: Installing standard acceleration sensors at all the above mentioned mounting positions; The exciter is started to excite the standard plate to obtain a first transfer function and a first sensitivity of each standard acceleration sensor; the first transfer function represents a parameter value of the standard acceleration sensor in response to the corresponding excitation, and the first sensitivity represents a relationship between a signal change of the standard acceleration sensor and a measured acceleration; Comparing and verifying the first transfer function of the standard acceleration sensor on the lower surface of the standard plate with the first transfer function of the standard acceleration sensor on the upper surface of the standard plate, thereby determining the accuracy of the multi-acceleration sensor parallel calibration system; If the first transfer functions of the standard acceleration sensors on the lower surface and the upper surface of the standard plate are the same or the difference is within an acceptable range, it is determined that the standard plate and the elastic element of the multi-acceleration sensor parallel calibration system are both reliable; replacing the standard acceleration sensor installed at the installation position with the acceleration sensor to be calibrated; Starting the exciter to perform the same excitation on the standard plate to obtain a second transfer function of each acceleration sensor to be calibrated; the second transfer function represents a parameter value of the acceleration sensor to be calibrated in response to the corresponding excitation; The acceleration sensor to be calibrated is calibrated according to the first transfer function, the first sensitivity and the second transfer function of the target installation position to obtain a second sensitivity of the target installation position; wherein the target installation position is any one of all the installation positions, and the second sensitivity represents a change relationship between a signal change of the acceleration sensor to be calibrated and a measured acceleration.

2. The method according to claim 1, characterized in that The standard plate is a rigid plate, and the first-order natural frequency of the standard plate is greater than 5 kHz.

3. The method according to claim 1, characterized in that The connection position between the exciter and the standard plate is located at the center of the standard plate.

4. The method according to claim 3, characterized in that Also includes: A standard acceleration sensor is mounted on a side of the standard plate facing the bottom plate.

5. The method according to claim 4, characterized in that There are two or more standard acceleration sensors installed on the side of the standard plate facing the bottom plate; and the two or more standard acceleration sensors are evenly distributed on the standard plate.

6. The method according to claim 3, characterized in that The mounting positions are evenly distributed on a side of the standard plate facing away from the base plate.

7. The method according to claim 1, characterized in that The elastic element, the bottom plate and the standard plate form a support structure, and the natural frequency of the support structure is less than 1 / 10 of the lowest calibration frequency of the acceleration sensor to be calibrated.

8. The method according to claim 1, characterized in that Also includes: The excitation rod, the exciter and the standard plate are connected at two ends of the excitation rod.

9. The method according to claim 8, characterized in that Also includes: A force sensor is provided, wherein the excitation rod is connected to the standard plate through the force sensor.

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