Device and method for calibrating tilt angle sensor

Abstract

The invention discloses a device and method for calibrating a tilt angle sensor, the device comprises a platform and a liquid pipe arranged on the platform, a top plane for placing the tilt angle sensor is formed at the top of the platform, the liquid pipe extends along the length direction, the liquid pipe is parallel to the top plane of the platform, and a diaphragm is arranged in the liquid pipe. The diaphragm divides a tube cavity of the liquid tube into a first tube cavity and a second tube cavity in the length direction, and the differential pressure sensor is used for detecting the pressure difference of the two sides of the diaphragm. A method for measuring and calibrating an inclination angle sensor by adopting a total station is abandoned, the inclination angle of the platform is calculated based on the pressure difference between the first pipe cavity and the second pipe cavity in the liquid pipe inclining along with the platform, and then the actual result measured by calibration equipment is compared, so that the aim of calibration is fulfilled. According to the technical scheme, the tedious steps of carrying a total station, placing a foot stool, leveling the total station, measuring and the like required by monitoring through the traditional total station are omitted, the efficiency is greatly improved, the cost is lower, and the precision is higher.

Description

Technical Field

[0001] The invention is used in the field of sensor calibration, and in particular relates to a device and method for calibrating a tilt sensor. Background Art

[0002] Inclination sensors are usually used for monitoring and detection in use scenarios, and the calibration of the accuracy of the inclinometer is a very important step. The accuracy determines the accuracy of monitoring. The traditional method of measuring inclinometers is total station measurement. The traditional method requires tedious steps such as carrying the total station, placing the tripod, leveling the total station, and measuring. It is inefficient, the process is cumbersome, and the accuracy is low. Summary of the invention

[0003] The purpose of the present invention is to solve at least one of the technical problems existing in the prior art and to provide a device and method for calibrating a tilt sensor.

[0004] The technical solution adopted by the present invention to solve the technical problem is:

[0005] In a first aspect, a device for calibrating an inclination sensor comprises a platform and a liquid tube arranged on the platform, wherein the top of the platform forms a top plane for placing the inclination sensor, the liquid tube extends along the length direction, the liquid tube is parallel to the top plane of the platform, a diaphragm is provided in the liquid tube, the diaphragm separates the lumen of the liquid tube into a first lumen and a second lumen along the length direction, and also comprises a differential pressure sensor for detecting the pressure difference on both sides of the diaphragm.

[0006] In combination with the first aspect, in some implementations of the first aspect, the differential pressure sensor includes a strain gauge disposed on a surface of the diaphragm.

[0007] In combination with the first aspect and the above-mentioned implementations, in some implementations of the first aspect, the diaphragm separates the lumen of the liquid tube into a symmetrical first lumen and a second lumen along the length direction.

[0008] In combination with the first aspect and the above-mentioned implementations, in some implementations of the first aspect, it also includes an inclination adjustment mechanism, which is connected to the platform and is used to adjust the inclination of the platform around an axis, and the axis is located on a plane parallel to the top plane and perpendicular to the length direction of the liquid tube.

[0009] In combination with the first aspect and the above-mentioned implementation methods, in some implementation methods of the first aspect, the inclination adjustment mechanism includes a first support leg, a second support leg and a third support leg, the first support leg and the second support leg are supported at one end of the platform, the third support leg is supported at the other end of the platform, the first support leg and the second support leg are of the same height and are symmetrically distributed on both sides of the liquid pipe, and the height of the third support leg is adjustable.

[0010] In combination with the first aspect and the above-mentioned implementations, in some implementations of the first aspect, a base is also included, and the first leg, the second leg and the third leg are placed on the top surface of the base.

[0011] In combination with the first aspect and the above-mentioned implementations, in some implementations of the first aspect, the liquid pipe is arranged at the bottom of the platform, and both ends of the liquid pipe are bent upward to form an upward pipe opening, and the pipe opening is provided with an end cover.

[0012] In a second aspect, a method for calibrating an inclination sensor is provided, wherein the device as described in any implementation of the first aspect is used, the inclination sensor is placed on the top plane of the platform, the first lumen and the second lumen of the liquid tube are respectively filled with liquid, the length direction of the liquid tube is the x-axis direction, the direction perpendicular to the top plane of the platform is the z-axis direction, and the direction perpendicular to the x-axis and the z-axis is the y-axis direction, and the calibration method comprises the following steps:

[0013] Measuring the pressure difference Δp1 on both sides of the diaphragm;

[0014] The platform is adjusted to rotate around the y-axis, the pressure difference Δp2 on both sides of the diaphragm is measured, and the inclination angle α of the platform rotating around the y-axis is obtained by calculation;

[0015] The inclination angle measured by the inclination sensor is compared with the inclination angle α.

[0016] In conjunction with the second aspect, in some implementations of the second aspect, calculating the inclination angle α includes the following steps:

[0017] Calculate the pressure difference change Δp before and after the platform rotates around the y-axis:

[0018] Δp=Δp2-Δp1

[0019] Calculate the height difference increment Δh before and after the platform rotates around the y-axis:

[0020]

[0021] Wherein, ρ is the density of the liquid in the liquid pipe, and g is the gravitational acceleration at the location of the device;

[0022] Calculate the inclination angle α of the platform around the y-axis:

[0023]

[0024] Wherein, L is the distance between the center of mass of the first lumen liquid and the center of mass of the second lumen liquid.

[0025] In combination with the second aspect and the above implementations, in some implementations of the second aspect, the tilt sensor is rotated 90° in the x- and y-axis planes, and the calibration method steps are repeated.

[0026] One of the above technical solutions has at least one of the following advantages or beneficial effects: the technical solution of the present invention abandons the method of using a total station to measure and calibrate the inclination sensor in the prior art, calculates the inclination of the platform based on the pressure difference between the first lumen and the second lumen in the liquid tube that tilts with the platform, and then compares the actual result measured by the calibration equipment, thereby achieving the purpose of calibration. The technical solution of the present invention eliminates the tedious steps of carrying the total station, placing the tripod, leveling the total station, and measuring required for traditional monitoring using a total station, greatly improving efficiency, and having lower costs and higher accuracy.

[0027] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0029] Figure 1 It is a structural isometric diagram of an embodiment of a device for calibrating a tilt sensor of the present invention;

[0030] Figure 2 It is a front view of the structure of an embodiment of a device for calibrating a tilt sensor of the present invention;

[0031] Figure 3 It is a schematic diagram of an embodiment of the device for calibrating the tilt sensor of the present invention after being tilted. DETAILED DESCRIPTION

[0032] This section will describe in detail the specific embodiments of the present invention. The preferred embodiments of the present invention are shown in the accompanying drawings. The purpose of the accompanying drawings is to supplement the description of the text part of the specification with graphics, so that people can intuitively and vividly understand each technical feature and the overall technical solution of the present invention, but it cannot be understood as a limitation on the scope of protection of the present invention.

[0033] In the present invention, if directions (up, down, left, right, front and back) are described, it is only for the convenience of describing the technical solution of the present invention, and does not indicate or imply that the technical features referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, it cannot be understood as a limitation of the present invention.

[0034] In the present invention, "several" means one or more, "multiple" means more than two, "greater than", "less than", "exceed" and the like are understood to exclude the number itself; "above", "below", "within" and the like are understood to include the number itself. In the description of the present invention, if there is a description of "first" or "second", it is only used for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0035] In the present invention, unless otherwise clearly defined, the words "set", "install", "connect" and the like should be understood in a broad sense, for example, they can be directly connected or indirectly connected through an intermediate medium; they can be fixedly connected or detachably connected or integrally formed; they can be mechanically connected or electrically connected or able to communicate with each other; they can be the internal connection of two elements or the interaction relationship between two elements. Those skilled in the art can reasonably determine the specific meanings of the above words in the present invention in combination with the specific content of the technical solution.

[0036] in, Figure 1 The reference direction coordinate system of the embodiment of the present invention is given. Figure 1 The embodiment of the present invention is described with reference to the direction shown.

[0037] See also Figure 1 , Figure 2 The embodiment of the present invention provides a device for calibrating an inclination sensor, comprising a platform 4 and a liquid tube 3 disposed on the platform 4, the top of the platform 4 forming a top plane 41 for placing the inclination sensor, the liquid tube 3 connected to the platform 4, the liquid tube 3 extending along the length direction, the liquid tube 3 parallel to the top plane 41 of the platform 4, a diaphragm 31 is disposed in the liquid tube 3, the diaphragm 31 divides the lumen of the liquid tube 3 into a first lumen 32 and a second lumen 33 along the length direction, and the device for calibrating the inclination sensor further comprises a differential pressure sensor 5 for detecting the pressure difference on both sides of the diaphragm 31. The specific calibration method of the device for calibrating the inclination sensor is described in detail below.

[0038] The technical solution of the present invention abandons the method of measuring and calibrating the inclination sensor using a total station in the prior art, and calculates the inclination of the platform 4 based on the pressure difference between the first lumen 32 and the second lumen 33 in the liquid tube 3 that tilts along with the platform 4, and then compares the actual result measured by the calibration equipment, thereby achieving the purpose of calibration. The technical solution of the present invention eliminates the tedious steps of carrying the total station, placing the tripod, leveling the total station, and measuring required for traditional monitoring using a total station, greatly improving efficiency, and having lower costs and higher precision.

[0039] In order to facilitate the placement of the inclination sensor, a slot or buckle can be set on the top plane 41 of the platform 4. The slot and buckle can limit the inclination sensor to the top plane 41 of the platform 4 along a specific direction to detect the inclination angle of the platform 4.

[0040] The differential pressure sensor 5 is used to detect the pressure difference on both sides of the diaphragm 31. In some embodiments, the differential pressure sensor 5 includes a strain gauge arranged on the surface of the diaphragm 31. The strain gauge can be made of a resistive material. When the strain gauge is mechanically deformed under the action of an external force, its resistance value changes accordingly, thereby further detecting the pressure difference on both sides of the diaphragm 31.

[0041] It is understandable that the device may also use other types of pressure sensors in the prior art, which will not be described in detail here.

[0042] The volumes of the first lumen 32 and the second lumen 33 are the same or different. For example, in some embodiments, the diaphragm 31 separates the lumen of the liquid tube 3 into a symmetrical first lumen 32 and a second lumen 33 along the length direction. The first lumen 32 and the second lumen 33 can be respectively injected with liquids of approximately equal weight to facilitate debugging and use.

[0043] When calibrating the inclination sensor, the inclination of the platform 4 needs to be adjusted and changed. The inclination of the platform 4 can be adjusted by placing the platform 4 on different inclined planes, or it can be adjusted manually, or a special inclination adjustment mechanism can be provided. For example, in some embodiments, the device for calibrating the inclination sensor also includes an inclination adjustment mechanism, which is connected to the platform 4 and is used to adjust the inclination of the platform 4 around an axis, and the axis is located on a plane parallel to the top plane 41 and perpendicular to the length direction of the liquid pipe 3. The inclination adjustment mechanism can more accurately tilt the platform 4 around the axis, avoiding errors in the data detected by the differential pressure sensor 5 due to the deviation of the tilt direction from the axis.

[0044] Further, in some embodiments, see Figure 1 , Figure 2 , Figure 3The inclination adjustment mechanism includes a first support leg 11, a second support leg 12 and a third support leg 13. The first support leg 11 and the second support leg 12 are supported at one end of the platform 4, and the third support leg 13 is supported at the other end of the platform 4. The first support leg 11 and the second support leg 12 are of equal height and symmetrically distributed on both sides of the liquid pipe 3, and the height of the third support leg 13 is adjustable. The third support leg 13 can be adjusted in height by telescoping, or by cooperating with a stud and a screw hole. When the inclination angle of the platform 4 is adjusted, the height of the third support leg 13 is adjusted, and the connecting line direction of the first support leg 11 and the second support leg 12 defines the swing axis of the platform 4, so that the platform 4 tilts around the axis, causing the liquid pressure difference on both sides of the liquid pipe 3 to change, constituting a pressure difference change at both ends of the differential pressure sensor 5, and the rotation angle of the platform 4 is calculated by the pressure difference change.

[0045] In some embodiments, see Figure 1 , Figure 2 The device for calibrating the inclination sensor also includes a base 2, and a first support leg 11, a second support leg 12 and a third support leg 13 are placed on the top surface of the base 2. The base 2 is located at the bottom of the device and plays a role in providing a plane support. The first support leg 11, the second support leg 12 and the third support leg 13 are located between the platform 4 and the base 2 to achieve the function of adjusting the inclination angle.

[0046] The liquid pipe 3 can be arranged on the side, top or bottom of the platform 4. In some embodiments, see Figure 1 , Figure 2 The liquid pipe 3 is arranged at the bottom of the platform 4, and the two ends of the liquid pipe 3 are bent upward to form an upward pipe opening, and the pipe opening is provided with an end cap. In this embodiment, the liquid pipe 3 is arranged at the bottom of the platform 4, which can avoid the top plane 41 of the platform 4, and is more convenient for calibrating the tilt sensor. At the same time, with the help of the upward pipe openings at both ends, it is convenient to fill the first tube cavity 32 and the second tube cavity 33 with liquid.

[0047] The embodiment of the present invention also provides a method for calibrating a tilt sensor, see Figure 1-Figure 3 , using the device in any of the above embodiments, the inclination sensor is placed on the top plane 41 of the platform 4, the first tube cavity 32 and the second tube cavity 33 of the liquid tube 3 are respectively filled with liquid, the length direction of the liquid tube 3 is the x-axis direction, the direction perpendicular to the top plane 41 of the platform 4 is the z-axis direction, and the direction perpendicular to the x-axis and the z-axis is the y-axis direction. The calibration method includes the following steps:

[0048] Measure the pressure difference Δp1 on both sides of the diaphragm 31;

[0049] The platform 4 is adjusted to rotate around the y-axis, and the pressure difference Δp2 on both sides of the diaphragm 31 is measured, and the inclination angle α of the platform 4 rotating around the y-axis is obtained by calculation;

[0050] The inclination angle measured by the inclination sensor is compared with the inclination angle α.

[0051] Specifically, see Figure 2 , Figure 3 , the calculation of the inclination angle α includes the following steps:

[0052] Calculate the pressure difference change Δp before and after the platform 4 rotates around the y-axis:

[0053] Δp=Δp2-Δp1

[0054] Calculate the height difference increment Δh before and after the platform 4 rotates around the y-axis:

[0055]

[0056] Wherein, ρ is the density of the liquid in the liquid pipe 3, and g is the gravitational acceleration at the location of the device;

[0057] Calculate the inclination angle α of platform 4 around the y-axis:

[0058]

[0059] Wherein, L is the distance between the center of mass of the liquid in the first lumen 32 and the center of mass of the liquid in the second lumen 33.

[0060] In some embodiments, the inclination sensor is rotated 90° in the x- and y-axis planes and the calibration method steps are repeated. This embodiment can measure the rotation angle measurement value of the inclination sensor in another direction; finally, the data measured by the inclination sensor is compared with the actual measured inclination, thereby achieving the purpose of calibration.

[0061] The embodiment of the present invention has a simple, compact and reasonable structure, eliminates the complicated process of traditional calibration using a total station, and greatly improves the efficiency of inclination correction of the inclination sensor.

[0062] In the description of this specification, the description with reference to the terms "example", "embodiment" or "some embodiments" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0063] Of course, the invention is not limited to the above-mentioned embodiments, and those skilled in the art may make equivalent modifications or substitutions without violating the spirit of the invention, and these equivalent modifications or substitutions are all included in the scope defined by the claims of this application.

Claims

1. A device for calibrating a tilt sensor, characterized in that: It includes a platform and a liquid tube arranged on the platform, the top of the platform forms a top plane for placing a tilt sensor, the liquid tube extends along the length direction, the liquid tube is parallel to the top plane of the platform, a diaphragm is provided in the liquid tube, the diaphragm separates the lumen of the liquid tube into a first lumen and a second lumen along the length direction, and also includes a differential pressure sensor for detecting the pressure difference on both sides of the diaphragm.

2. The device for calibrating a tilt sensor according to claim 1, characterized in that: The differential pressure sensor includes a strain gauge disposed on a surface of the diaphragm.

3. The device for calibrating a tilt sensor according to claim 1, characterized in that: The diaphragm separates the lumen of the liquid tube into a first lumen and a second lumen that are symmetrical along the length direction.

4. The device for calibrating a tilt sensor according to claim 1, characterized in that: It also includes an inclination adjustment mechanism, which is connected to the platform and is used to adjust the inclination of the platform around an axis, where the axis is located on a plane parallel to the top plane and perpendicular to the length direction of the liquid pipe.

5. The device for calibrating a tilt sensor according to claim 4, characterized in that: The inclination adjustment mechanism includes a first support leg, a second support leg and a third support leg. The first support leg and the second support leg are supported at one end of the platform, and the third support leg is supported at the other end of the platform. The first support leg and the second support leg are of the same height and are symmetrically distributed on both sides of the liquid pipe. The height of the third support leg is adjustable.

6. The device for calibrating a tilt sensor according to claim 5, characterized in that: It also includes a base, wherein the first supporting leg, the second supporting leg and the third supporting leg are placed on the top surface of the base.

7. The device for calibrating a tilt sensor according to claim 1, characterized in that: The liquid pipe is arranged at the bottom of the platform, and both ends of the liquid pipe are bent upward to form an upward pipe opening, and the pipe opening is provided with an end cover.

8. A method for calibrating a tilt sensor, characterized in that: Using the device according to any one of claims 1 to 7, placing the inclination sensor on the top plane of the platform, filling the first lumen and the second lumen of the liquid tube with liquid respectively, taking the length direction of the liquid tube as the x-axis direction, taking the direction perpendicular to the top plane of the platform as the z-axis direction, and taking the direction perpendicular to the x-axis and the z-axis as the y-axis direction, the calibration method comprises the following steps: Measuring the pressure difference Δp1 on both sides of the diaphragm; The platform is adjusted to rotate around the y-axis, the pressure difference Δp2 on both sides of the diaphragm is measured, and the inclination angle α of the platform rotating around the y-axis is obtained by calculation; The inclination angle measured by the inclination sensor is compared with the inclination angle α.

9. The method for calibrating a tilt sensor according to claim 8, characterized in that: Calculating the inclination angle α includes the following steps: Calculate the pressure difference change Δp before and after the platform rotates around the y-axis: Δp=Δp2-Δp1 Calculate the height difference increment Δh before and after the platform rotates around the y-axis: Wherein, ρ is the density of the liquid in the liquid pipe, and g is the gravitational acceleration at the location of the device; Calculate the inclination angle α of the platform around the y-axis: Wherein, L is the distance between the center of mass of the first lumen liquid and the center of mass of the second lumen liquid.

10. The method for calibrating a tilt sensor according to claim 8, characterized in that: The tilt sensor is rotated 90° in the x- and y-axis planes, and the calibration method steps are repeated.

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