An inertial sensor core and an inertial sensor detection method

Abstract

The present invention provides an inertial sensor core and an inertial sensor detection method, belonging to the field of inertial measurement technology. The inertial sensor core includes a base and an inertial module. The base has three mounting surfaces evenly distributed around its central axis, and the mounting surfaces are gradually inclined away from the central axis from top to bottom; the inertial module includes three circuit boards and wires connected between the three circuit boards, and the three circuit boards are mounted in a one-to-one correspondence with the three mounting surfaces. The inertial sensor detection method includes: S10: loading the inertial sensor core into a carrier; S20: the current vector space obtained by measurement is [X1, Y1, Z1] T ; S30: Use the transformation matrix C to calculate the actual orthogonal space vector [X, Y, Z] T :#imgabs0#.

Description

Technical Field

[0001] The invention belongs to the technical field of inertial measurement, and in particular relates to an inertial sensor core and a detection method of the inertial sensor. Background Art

[0002] The inertial measurement unit (IMU) can measure the angular velocity and acceleration information of the carrier in three orthogonal directions, thereby obtaining the angular motion state and linear motion state of the carrier. The IMU produced based on MEMS inertial devices has the characteristics of small size, low power consumption, good short-term stability and seismic resistance, and can be used in a smaller space environment. Therefore, it is widely used in short-term attitude control, inertial navigation and other fields.

[0003] The existing IMU design method of MEMS inertial devices is mainly to install the MEMS inertial devices in the three sensitive directions of the IMU in a pairwise orthogonal fixing manner, and compensate the installation error angle through the IMU system to achieve accurate measurement of the angular velocity or acceleration information of the three orthogonal axes; this installation method can meet most application occasions, but it still has the following defects:

[0004] (1) Some space limitations are high and cannot provide enough space to achieve orthogonal installation of MEMS inertial devices;

[0005] (2) The measuring range of the MEMS inertial device itself cannot meet the actual use requirements of a certain axis of the carrier;

[0006] (3) There are differences in the performance of inertial devices in the three axes, resulting in poor environmental adaptability of the inertial devices in one axis. Summary of the invention

[0007] The embodiments of the present invention provide an inertial sensor core and an inertial sensor detection method, aiming to solve the technical problems that the existing orthogonal installation occupies a large space, its own range cannot meet the use requirements, and the environmental adaptability is poor due to performance differences.

[0008] In a first aspect, an embodiment of the present invention provides an inertial sensor core, comprising:

[0009] The base has three mounting surfaces evenly distributed around its central axis, and the mounting surfaces are gradually inclined away from the central axis from top to bottom;

[0010] The inertial module includes three circuit boards and wires connected between the three circuit boards. The three circuit boards are mounted on the three mounting surfaces in a one-to-one correspondence.

[0011] In combination with the first aspect, in a possible implementation manner, the base further has three assembly parts, each of the mounting surfaces is located between two adjacent assembly parts, and the assembly part is higher than the mounting surface.

[0012] In combination with the first aspect, in a possible implementation manner, each of the mounting surfaces is recessed with a receiving groove, and the receiving groove is used to receive a chip on the corresponding circuit board.

[0013] In combination with the first aspect, in a possible implementation manner, two opposite side walls of the accommodating groove are both provided with openings.

[0014] In combination with the first aspect, in a possible implementation manner, both upper and lower sides of the mounting surface are provided with blocking bars protruding from the mounting surface.

[0015] In combination with the first aspect, in a possible implementation manner, an angle between the circuit board and the central axis is 45° to 60°.

[0016] In combination with the first aspect, in a possible implementation manner, a supporting surface perpendicular to the central axis is provided on the top of the base, and a chamfer is provided between the supporting surface and the mounting surface.

[0017] In combination with the first aspect, in a possible implementation manner, the circuit board is bonded to the corresponding mounting surface.

[0018] The solution shown in the embodiment of the present application is compared with the prior art. The inertial sensor core in the embodiment is encapsulated in a shell to form an inertial sensor, which can be installed on a carrier. When the carrier undergoes dynamic changes, the angular velocity and acceleration changes of the carrier are determined by measuring the changes in the space vector. The three circuit boards on the inertial module are installed in a manner that fits the mounting surface. The inertial module after installation is in an inverted shape. The overall height of the inertial module is the length of the component of the height of the circuit board projected on the central axis, which improves space utilization and can adapt to a more compact installation environment. When installed in a non-orthogonal manner, the data needs to be converted into orthogonal data. If the measurement range of a single orthogonal axis exceeds the range in an actual working condition, the measurement range on each measurement axis does not need to meet the measurement range required in the working condition through the decomposition of the non-orthogonal axis, thereby achieving over-range measurement. The non-orthogonal installation method can make a certain orthogonal axis have components on multiple measurement axes. During use, a measurement axis that is more suitable for the working condition can be selected to improve adaptability.

[0019] In a second aspect, an embodiment of the present invention further provides a detection method of an inertial sensor, using the above-mentioned inertial sensor core, comprising the following steps:

[0020] S10: installing the inertial sensor core into a carrier;

[0021] S20: The current vector space measured is [X1, Y1, Z1] T ;

[0022] S30: Calculate the actual orthogonal space vector [X, Y, Z] using the transformation matrix C T :

[0023] .

[0024] In conjunction with the second aspect, in a possible implementation manner, the conversion matrix C is:

[0025] Get the unit vector [1,0,0] T , [0,1,0] T , [0,0,1] T ;

[0026] Calculate the unit vector [1,0,0] T The projection vectors on the three circuit boards are C 11 , C 12 , C 13 ;

[0027] Calculate the unit vector [0,1,0] T The projection vectors on the three circuit boards are C 21 , C 22 , C 23 ;

[0028] Calculate the unit vector [0,0,1] T The projection vectors on the three circuit boards are C 31 , C 32 , C 33 .

[0029] Compared with the prior art, the solution shown in the embodiment of the present application adopts a non-orthogonal installation method, and finally the data needs to be converted into orthogonal data. If the measurement range of a single orthogonal axis in an actual working condition exceeds the range, through the decomposition of the non-orthogonal axis, the measurement range on each measurement axis does not need to reach the measurement range required in the working condition, thereby realizing over-range measurement; the use of a non-orthogonal installation method can make a certain orthogonal axis have components on multiple measurement axes, and during use, a measurement axis that is more suitable for the working condition can be selected to improve adaptability. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 A schematic diagram of the main structure of an inertial sensor core provided by an embodiment of the present invention;

[0031] Figure 2A schematic diagram of the three-dimensional structure of an inertial sensor core provided by an embodiment of the present invention;

[0032] Figure 3 A schematic diagram of the three-dimensional structure of a base used in an embodiment of the present invention;

[0033] Figure 4 It is a schematic diagram of the three-dimensional structure of the inertial module used in an embodiment of the present invention.

[0034] Description of reference numerals:

[0035] 10-base; 11-installation surface; 12-assembly portion; 13-accommodation groove; 14-opening; 15-stop bar; 16-supporting surface; 17-rounded corner;

[0036] 20- inertial module; 21- circuit board; 22- wire. DETAILED DESCRIPTION

[0037] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0038] In the claims, specifications and the above-mentioned drawings of the present invention, the terms "upper", "lower", "top" and "bottom" are the same as the Z-axis direction; other directional words, unless otherwise explicitly defined, such as the use of terms "front", "back", "inside", "outside", "center", "lateral", "longitudinal", "horizontal", "vertical", "left", "right", "clockwise", "counterclockwise", "high", "low" and the like to indicate directions or positional relationships are based on the directions and positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the specific protection scope of the present invention.

[0039] In the claims, specification and the above drawings of the present invention, unless otherwise clearly defined, if the term "fixed connection" or "fixed connection" is used, it should be understood in a broad sense, that is, any connection method without a displacement relationship and relative rotation relationship between the two, that is to say, including non-detachable fixed connection, detachable fixed connection, integrated connection and fixed connection through other devices or elements.

[0040] In the claims, description and drawings of the present invention, if the terms "include", "have" and their variations are used, they are intended to mean "including but not limited to".

[0041] Please also read Figures 1 to 4The inertial sensor core provided by the present invention is now described. The inertial sensor core includes a base 10 and an inertial module 20. The base 10 has three mounting surfaces 11 evenly distributed around its central axis, and the mounting surfaces 11 are gradually inclined away from the central axis from top to bottom; the inertial module 20 includes three circuit boards 21 and wires 22 connected between the three circuit boards 21. The three circuit boards 21 are mounted in a one-to-one correspondence with the three mounting surfaces 11.

[0042] Specifically, the circuit board 21 is bonded to the corresponding mounting surface 11 .

[0043] It should be noted that the central axis of the base 10 is the Z axis.

[0044] For ease of understanding, a simple description of a traditional inertial sensor is now given: the circuit board 21 in the traditional inertial sensor is installed in an orthogonal manner, and the corresponding base 10 also needs to have three mounting plates, and the plate surfaces of the three mounting plates are respectively parallel to the XY plane, the YZ plane, and the XZ plane. Therefore, the installed circuit board 21 is also parallel to the XY plane, the YZ plane, and the XZ plane, respectively. Then, the measured spatial vector is directly an orthogonal spatial vector, and the angular velocity and acceleration information can be directly obtained.

[0045] Compared with the prior art, the inertial sensor core provided in the present embodiment is encapsulated in a housing to form an inertial sensor, which can be installed on a carrier. When the carrier undergoes dynamic changes, the angular velocity and acceleration changes of the carrier are determined by measuring the changes in the space vector. The three circuit boards 21 on the inertial module 20 are installed in contact with the mounting surface 11, and the inertial module 20 after installation is in an inverted shape. The overall height of the inertial module 20 is the length of the component of the height of the circuit board 21 projected on the central axis, which improves space utilization and can adapt to a more compact installation environment. When installed in a non-orthogonal manner, the data needs to be converted into orthogonal data. If the measurement range of a single orthogonal axis exceeds the range in an actual working condition, the measurement range on each measurement axis does not need to meet the measurement range required in the working condition through the decomposition of the non-orthogonal axis, thereby achieving over-range measurement. The non-orthogonal installation method can make a certain orthogonal axis have components on multiple measurement axes. In use, a measurement axis that is more suitable for the working condition can be selected to improve adaptability.

[0046] In some embodiments, an improved implementation of the base 10 can be as follows: Figures 1 to 3 See the structure shown. Figures 1 to 3The base 10 also has three assembly parts 12, each mounting surface 11 is located between two adjacent assembly parts 12, and the assembly part 12 is higher than the mounting surface 11. The three assembly parts 12 and the three mounting surfaces 11 are alternately distributed, which can ensure the uniformity of the three installations around the Z axis. The base 10 is fixed by the assembly parts 12 on the base 10, which can improve the stability of the base 10 after being fixed, thereby improving the accuracy of the measurement; wherein the assembly part 12 is higher than the mounting surface 11, and the circuit board 21 can be limited on both sides of the circuit board 21 after it is installed, so that the circuit board 21 is conveniently aligned with the mounting surface 11 when installed, and the circuit board 21 has higher stability after installation.

[0047] Optionally, the assembly part 12 is a platform with a table top perpendicular to the Z axis, and each assembly part 12 is provided with a through hole for installing a threaded connector.

[0048] In some embodiments, an improved implementation of the base 10 can be as follows: Figure 3 See the structure shown. Figure 3 , each mounting surface 11 is recessed with a receiving groove 13, and the receiving groove 13 is used to receive the chip on the corresponding circuit board 21. A chip needs to be soldered on each circuit board 21. When installing the circuit board 21, one side of the chip on the circuit board 21 faces the mounting surface 11, and the chip is placed in the receiving groove 13. The circuit board 21 is connected to the mounting surface 11. The chip occupies the space of the base 10, which can further save the space occupied by the inertial sensor core; the chip is placed in the receiving groove 13 and soldered to the circuit board 21, so the receiving groove 13 limits the position of the chip and the circuit board 21 at the same time. After the chip is placed in the receiving groove 13, the circuit board 21 can be aligned and fitted with the mounting surface 11, which is convenient for the installation of the circuit board 21.

[0049] In some embodiments, an improved implementation of the above-mentioned receiving groove 13 can be adopted as follows Figure 3 See the structure shown. Figure 3 , openings 14 are provided on opposite side walls of the receiving groove 13. The openings 14 on both sides of the receiving groove 13 can be used to observe the installation of the chip in the receiving groove 13 from the openings 14 when assembling the circuit board 21; and the openings 14 on both sides provide space for taking and placing the circuit board 21 on the mounting surface 11, and when clamping the circuit board 21, the position of the circuit board 21 corresponding to the openings 14 can be clamped to avoid bumping the mounting surface 11 and affecting the installation stability of the circuit board 21; after the circuit board 21 is installed on the mounting surface 11, the receiving groove 13 will be closed, and at this time, the chip in the receiving groove 13 can also be cooled through the openings 14 to extend the service life.

[0050] Optionally, the opening 14 extends to the mounting surface 11 .

[0051] In some embodiments, an improved implementation of the base 10 can be as follows: Figure 3 See the structure shown. Figure 3 The upper and lower sides of the mounting surface 11 are both provided with stoppers 15 protruding from the mounting surface 11. After the circuit board 21 is placed on the mounting surface 11, the upper and lower sides are limited by the two stoppers 15, and the left and right sides are limited by the two assembly parts 12, so as to facilitate the connection operation between the circuit board 21 and the base 10 and ensure the installation accuracy of the circuit board 21.

[0052] In some implementations, a specific implementation of the circuit board 21 may adopt the following structure, where the angle between the circuit board 21 and the central axis is 45° to 60°. The overall height of the inertial module 20 will change with different inclination angles of the circuit board 21. The angle between the circuit board 21 and the central axis may be adjusted according to the actual installation environment.

[0053] In some embodiments, an improved implementation of the base 10 can be as follows: Figure 3 See the structure shown. Figure 3 The top of the base 10 is provided with a supporting surface 16 perpendicular to the central axis, and a rounded corner 17 is provided between the supporting surface 16 and the mounting surface 11. Since the three circuit boards 21 need to be connected by wires 22, the wires 22 can be placed on the supporting surface 16 after connecting the three circuit boards 21. By rounding the corners 17 between the supporting surface 16 and the mounting surface 11, friction cutting of the wires 22 at the sharp corners can be avoided, thereby improving product quality.

[0054] Based on the same inventive concept, an embodiment of the present application further provides a detection method of an inertial sensor, using the above-mentioned inertial sensor core, comprising the following steps:

[0055] S10: Installing the inertial sensor core into the carrier;

[0056] S20: The current vector space measured is [X1, Y1, Z1] T ;

[0057] S30: Calculate the actual orthogonal space vector [X, Y, Z] using the transformation matrix C T :

[0058] .

[0059] Compared with the prior art, the detection method of the inertial sensor provided in this embodiment is installed in a non-orthogonal manner, and finally the data needs to be converted into orthogonal data. If the measurement range of a single orthogonal axis exceeds the range in an actual working condition, the measurement range on each measurement axis does not need to reach the measurement range required in the working condition through the decomposition of the non-orthogonal axis, thereby realizing over-range measurement. The non-orthogonal installation method can make a certain orthogonal axis have components on multiple measurement axes, and during use, a measurement axis that is more suitable for the working condition can be selected to improve adaptability.

[0060] In some embodiments, the conversion matrix C is:

[0061] Get the unit vector [1,0,0] T , [0,1,0] T , [0,0,1] T ;

[0062] Calculate the unit vector [1,0,0] T The projection vectors on the three circuit boards 21 are C 11 , C 12 , C 13 ;

[0063] Calculate the unit vector [0,1,0] T The projection vectors on the three circuit boards 21 are C 21 , C 22 , C 23 ;

[0064] Calculate the unit vector [0,0,1] T The projection vectors on the three circuit boards 21 are C 31 , C 32 , C 33 .

[0065] Depending on the different angles between the circuit board 21 and the central axis, the corresponding values ​​in the transformation matrix are also different. The projection vectors on the three circuit boards 21 are calculated based on the unit vector to obtain the current transformation matrix, thereby calculating the actual orthogonal space vector.

[0066] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An inertial sensor core, characterized in that: include: The base has three mounting surfaces evenly distributed around its central axis, and the mounting surfaces are gradually inclined away from the central axis from top to bottom; The inertial module comprises three circuit boards and wires connected between the three circuit boards, the three circuit boards are mounted in a one-to-one correspondence with the three mounting surfaces, the three circuit boards on the inertial module are mounted in a mounted conformity with the mounting surfaces, the inertial module after installation is in an inverted shape, and the overall height of the inertial module is the length of the component of the height of the circuit board projected on the central axis; The base is also provided with three assembly parts, each of the mounting surfaces is located between two adjacent assembly parts, and the assembly part is higher than the mounting surface. After the circuit board is installed, the assembly parts limit the circuit board on both sides of the circuit board.

2. The inertial sensor core according to claim 1, characterized in that: Each mounting surface is recessed with a receiving groove, and the receiving groove is used to receive a chip on the corresponding circuit board.

3. The inertial sensor core according to claim 2, characterized in that: The two opposite side walls of the containing groove are both provided with openings.

4. The inertial sensor core according to claim 1, characterized in that: The upper and lower sides of the installation surface are both provided with blocking bars protruding from the installation surface.

5. The inertial sensor core according to claim 1, characterized in that: The included angle between the circuit board and the central axis is 45° to 60°.

6. The inertial sensor core according to claim 1, characterized in that: A supporting surface perpendicular to the central axis is provided on the top of the base, and a rounded corner is provided between the supporting surface and the mounting surface.

7. The inertial sensor core according to claim 1, characterized in that: The circuit board is bonded to the corresponding mounting surface.

8. A detection method of an inertial sensor, characterized in that: Using the inertial sensor core according to any one of claims 1 to 7, comprising the following steps: S10: installing the inertial sensor core into a carrier; S20: The current vector space measured is [X1, Y1, Z1] T ; S30: Calculate the actual orthogonal space vector [X, Y, Z] using the transformation matrix C T : 。 9. The detection method of the inertial sensor according to claim 8, characterized in that: The conversion matrix C is: Get the unit vector [1,0,0] T , [0,1,0] T , [0,0,1] T ; Calculate the unit vector [1,0,0] T The projection vectors on the three circuit boards are C 11 , C 12 , C 13 ; Calculate the unit vector [0,1,0] T The projection vectors on the three circuit boards are C 21 , C 22 , C 23 ; Calculate the unit vector [0,0,1] T The projection vectors on the three circuit boards are C 31 , C 32 , C 33 .

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