IMU-UWB-based double-anchor two-dimensional positioning method, device and equipment
By combining UWB ranging and IMU inertial navigation data, the intersection of the distance circle is constructed and the yaw angle is calculated. Ambiguous points are eliminated, which solves the problems of high cost of UWB positioning and cumulative error of IMU, and realizes low-cost and high-precision car digital key positioning.
Patent Information
- Application Number
- CN202511148162.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-16
- Publication Date
- 2025-10-17
AI Technical Summary
Existing UWB positioning technology requires the deployment of multiple anchor points in car digital keys, resulting in high costs and increased complexity of the positioning system. When the IMU is used alone, the cumulative error is large and accurate positioning cannot be achieved.
By combining high-precision ranging data from UWB and inertial navigation data from IMU, dual-anchor point positioning is achieved by constructing the intersection of the distance circle and calculating the yaw angle, eliminating fuzzy points and retaining the true positioning point.
Achieving precise positioning with only two base stations reduces deployment costs, improves positioning accuracy, and simplifies the positioning system.
Smart Images
Figure CN120802174A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the field of automobile digital key positioning technology, in particular to a double-anchor two-dimensional positioning method, device and equipment based on IMU-UWB. BACKGROUND
[0002] UWB (Ultra Wide Band, Ultra Wide Band) positioning technology is widely used in indoor positioning, industrial automation and automobile digital key fields due to its high precision and strong anti-interference ability. In the application of automobile digital key, the existing multi-anchor point scheme needs to deploy multiple anchor point devices to ensure precision, which greatly increases the positioning cost and complexity.
[0003] A nine-axis inertial measurement unit (IMU) usually includes an accelerometer, a gyroscope and a magnetometer, which can measure acceleration, angular velocity and magnetic field data. IMU products are widely used in consumer electronics, industrial control, unmanned aerial vehicles and other fields, and can provide all-around attitude detection and motion tracking. IMU products usually have a built-in digital motion processor (DMP) that can fuse nine-axis sensor data and output real-time device pose information, reducing the burden on the main control and improving data processing efficiency. However, due to its cumulative error and other problems, it cannot be used for positioning alone and is often used in combination with other positioning technologies.
[0004] Therefore, how to combine UWB and IMU to achieve accurate positioning of automobile digital key has become a problem that needs to be solved. SUMMARY
[0005] The present application provides a double-anchor two-dimensional positioning method, device and equipment based on IMU-UWB, which combines the high-precision ranging of UWB and the inertial navigation data of IMU to assist decision-making, realizes double-anchor positioning, and has high positioning accuracy.
[0006] In a first aspect, the present application provides a double-anchor two-dimensional positioning method based on IMU-UWB, which includes: Measuring the distance between the key and the two anchors based on UWB technology, constructing two distance circles with the distance as the radius, calculating the intersection of the two distance circles, and obtaining the real positioning point and the ambiguous point; According to the intersection and the intersection obtained by corresponding calculation again after the key moves, the yaw angle between the intersections before and after the key moves is determined; Based on IMU, the real-time yaw angle of the key is obtained, the real-time yaw angle and the yaw angle are compared, the ambiguous point is eliminated and the real positioning point is retained, and the positioning of the key is updated.
[0007] In combination with the first aspect, in an implementation manner, the distance between the key and the two anchor points is measured based on the UWB technology, two distance circles are constructed with the distance as the radius, the intersection points of the two distance circles are calculated to obtain the real positioning point and the ambiguous point, and specifically, the method comprises the following steps: The distance between the key and the first anchor point and the distance between the key and the second anchor point are respectively obtained by using the double-side and double-direction ranging method based on the UWB technology; A distance circle is constructed with the first anchor point as the center and the distance between the key and the first anchor point as the radius, and a distance circle is constructed with the second anchor point as the center and the distance between the key and the second anchor point as the radius; The intersection points of the two distance circles are calculated, and one of the intersection points of the two distance circles is the real positioning point and the other is the ambiguous point.
[0008] In combination with the first aspect, in an implementation manner, For the distance circle corresponding to the first anchor point, it is represented as:
[0009] wherein, represents the horizontal coordinate of the key, represents the vertical coordinate of the key, the first anchor point is located at the center of the coordinate system, and the coordinate is represented as , represents the distance between the key and the first anchor point; For the distance circle corresponding to the second anchor point, it is represented as:
[0010] wherein, represents the distance between the first anchor point and the second anchor point, and the coordinate of the second anchor point is , represents the distance between the key and the second anchor point; For the intersection points of the two distance circles, it is represented as: .
[0011] In combination with the first aspect, in an implementation manner, the yaw angle between the intersection points before and after the movement of the key is determined according to the intersection points and the intersection points calculated again after the movement of the key, and specifically, the method comprises the following steps: The intersection points calculated before the movement of the key are obtained , and the intersection points calculated after the movement of the key are obtained , ; The yaw angle between the intersection point and the intersection point is calculated, and the yaw angle between the intersection point and the intersection point is calculated.
[0012] In combination with the first aspect, in an implementation manner, For the yaw angle between the intersection point and the intersection point , specifically:
[0013] Wherein, The yaw angle between the intersection point and the intersection point , , , The intermediate quantity is represented by , , ; For the yaw angle between the intersection point and the intersection point , specifically:
[0014] Wherein, The yaw angle between the intersection point and the intersection point .
[0015] In combination with the first aspect, in an implementation manner, the real-time yaw angle of the key based on the IMU is specifically: The DMP of the IMU fuses the nine-axis data output of the IMU to output a quaternion, and the real-time yaw angle of the key is obtained based on the conversion of the quaternion to Euler angle, wherein the real-time yaw angle is represented as:
[0016] Wherein, The real-time yaw angle is represented by a quaternion, which is a hypercomplex number and is represented as , and after normalization, it satisfies .
[0017] In combination with the first aspect, in an implementation manner, the comparison between the real-time yaw angle and the yaw angle eliminates ambiguous points and retains real positioning points, and realizes the positioning update of the key, specifically including: The yaw angle between the intersection point before and after the key moves is compared and calculated with the real-time yaw angle: If , the intersection point is a real positioning point, and the intersection point is retained, and the intersection point is eliminated, wherein represents a set threshold value; If , the intersection point keep the intersection point , remove the intersection point .
[0018] In combination with the first aspect, in an implementation, for the judgment of the key movement, specifically: The acceleration data output by the IMU is compared with a preset threshold to determine whether the key moves.
[0019] The second aspect, the embodiment of the application provides a two-dimensional positioning device based on IMU-UWB double anchor points, the two-dimensional positioning device based on IMU-UWB double anchor points comprises: An information acquisition module is used to measure the distance between the key and two anchor points based on UWB technology, and obtain the real-time yaw angle of the key based on IMU; A calculation module is used to construct two distance circles with distance as radius according to the distance data and real-time yaw angle data obtained by the information acquisition module, calculate the intersection points of the two distance circles, obtain the real positioning point and the ambiguous point, and determine the yaw angle between the intersection points before and after the key moves according to the intersection points and the intersection points calculated again after the key moves, and compare the real-time yaw angle with the yaw angle, remove the ambiguous point and keep the real positioning point; A positioning information display module is used to display the positioning of the key based on the real positioning point data.
[0020] The third aspect, the embodiment of the application provides a two-dimensional positioning device based on IMU-UWB double anchor points, the two-dimensional positioning device based on IMU-UWB double anchor points comprises a processor, a memory, and a two-dimensional positioning program based on IMU-UWB double anchor points stored on the memory and executable by the processor, wherein when the two-dimensional positioning program based on IMU-UWB double anchor points is executed by the processor, the steps of the two-dimensional positioning method based on IMU-UWB double anchor points are implemented.
[0021] The technical scheme provided by the embodiment of the application has the beneficial effects of: In view of the problems that the existing UWB digital key anchor points are easy to cause cost increase and positioning system complexity, the IMU pose data is fused with the UWB ranging data, the relative yaw angle between the intersection point coordinates of the current time and the last time is calculated according to the ranging values of the two times, and then the real positioning point coordinates are confirmed according to the yaw angle calculated by the IMU for auxiliary decision, the UWB and IMU functions are integrated on the digital key, and only two base stations are needed to realize accurate positioning, which is simple and has low deployment cost. BRIEF DESCRIPTION OF DRAWINGS
[0022] Figure 1A flowchart of a two-dimensional positioning method based on IMU-UWB double anchor points of the present application is shown in FIG. 1. Figure 2 A schematic diagram for calculating the yaw angle is shown in FIG. 3. Figure 3 A schematic diagram of the principle of the two-dimensional positioning method based on IMU-UWB double anchor points of the present application is shown in FIG. 4. Figure 4 A functional module diagram of the two-dimensional positioning device based on IMU-UWB double anchor points of the present application is shown in FIG. 5. Figure 5 A hardware structure diagram of the two-dimensional positioning device based on IMU-UWB double anchor points of the present application is shown in FIG. 6. DETAILED DESCRIPTION
[0023] In order to enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of the present application.
[0024] In order to make the purpose, technical solutions and advantages of the present application clearer, the embodiments of the present application will be described in further detail below with reference to the accompanying drawings.
[0025] In a first aspect, the embodiments of the present application provide a two-dimensional positioning method based on IMU-UWB double anchor points. By combining the high-precision ranging of UWB and the inertial navigation data of IMU, the double anchor point positioning is realized, and the positioning result mainly depends on the ranging data of UWB. On the basis of the centimeter-level ranging accuracy of UWB, the positioning accuracy can be significantly improved.
[0026] In an embodiment, referring to Figure 1 , Figure 1 A flowchart of the two-dimensional positioning method based on IMU-UWB double anchor points of the present application is shown in FIG. 1. As shown in FIG. 1, the two-dimensional positioning method based on IMU-UWB double anchor points includes: Figure 1 S1: measuring the distances between the key and the two anchor points based on the UWB technology, constructing two distance circles with the distances as radii, calculating the intersection points of the two distance circles, and obtaining the real positioning point and the ambiguous point; S2: determining the yaw angle between the intersection points before and after the movement of the key according to the intersection points and the intersection points obtained by corresponding calculation again after the movement of the key. S3: Based on the IMU, the real-time yaw angle of the key is obtained, the real-time yaw angle is compared with the yaw angle, the ambiguous points are eliminated and the real positioning points are retained, and the positioning update of the key is realized, that is, after the key moves, the positioning coordinates are uploaded to the base station to update the key position information.
[0027] Further, in an embodiment, the distance between the key and the two anchor points is measured based on the UWB technology, two distance circles are constructed with the distance as the radius, the intersection of the two distance circles is calculated, and the real positioning point and the ambiguous point are obtained, which specifically includes: S101: The distance between the key and the first anchor point and the distance between the key and the second anchor point are obtained respectively based on the double-sided and double-direction ranging method of UWB technology; S102: A distance circle is constructed with the first anchor point as the center and the distance between the key and the first anchor point as the radius, and a distance circle is constructed with the second anchor point as the center and the distance between the key and the second anchor point as the radius; S103: The intersection of the two distance circles is calculated, and one of the intersection points of the two distance circles is a real positioning point and the other is an ambiguous point.
[0028] In this application, for the distance circle corresponding to the first anchor point, it is represented as:
[0029] wherein, represents the horizontal coordinate of the key, represents the vertical coordinate of the key, the first anchor point is located at the center of the coordinate system, and the coordinate is represented as , represents the distance between the key and the first anchor point; For the distance circle corresponding to the second anchor point, it is represented as:
[0030] wherein, represents the distance between the first anchor point and the second anchor point, and the coordinate of the second anchor point is , represents the distance between the key and the second anchor point; For the intersection of the two distance circles, it is represented as: .
[0031] Specifically, the relative distance between the key and the first anchor point and the second anchor point is obtained based on the double-sided and double-direction ranging method of UWB technology, as shown in Figure 2 , wherein A represents the first anchor point, B represents the second anchor point, for the sake of simplifying the calculation, the coordinate of the first anchor point is set as , the coordinate of the second anchor point is set as , and the coordinate of the key is set as , the distances between the key and the two anchor points obtained based on UWB ranging are 、 .
[0032] Construct a distance circle with the anchor point coordinates as the center and the distance between the key and the anchor point as the radius. The equation of the distance circle constructed between the first anchor point and the key is: , the distance circle equation between the second anchor point and the key is Based on the distance circle equation, the intersection point between the two distance circles can be solved, where one intersection point is the real positioning point and the other intersection point is the fuzzy point.
[0033] Furthermore, in one embodiment, determining the yaw angle between the intersection points before and after the key is moved based on the intersection point and the corresponding intersection point calculated again after the key is moved specifically includes: S201: Obtain the intersection point calculated before the key moves 、 , and the corresponding intersection calculated after the key moves 、 ; S202: Calculate the intersection point Intersection The yaw angle between them, and the intersection point Intersection Yaw angle between.
[0034] In this application, for the intersection Intersection The yaw angle between
[0035] in, Indicates the intersection Intersection The yaw angle between 、 、 Indicates the intermediate quantity, , , ; For the intersection Intersection The yaw angle between
[0036] in, Indicates the intersection Intersection The yaw angle between .
[0037] Specifically, initially, according to the equations of the two distance circles, two intersection points symmetrical about the coordinate axis x can be obtained, seeFigure 2 is shown, i.e. point is shown, i.e. point ; after the key moves again, two distance circles are constructed according to the distance between the key and the anchor points, and according to the equations of the two distance circles obtained again, two intersection points symmetrical about the coordinate axis x are obtained again, i.e. point is shown, i.e. point ; the angle between the line connecting the point and the positive direction of the y-axis is the yaw angle , and by analogy, the angle between the line connecting the point and the positive direction of the y-axis is the yaw angle . The projection coordinate of the point on the x-axis is A triangle is constructed with the point , the point , and the point , and according to the cosine formula of the triangle: ; i.e. ; Since the intersection points obtained are symmetrical about the x-axis, it can be known that the calculated yaw angle is complementary to the yaw angle , i.e. .
[0038] Further, in an embodiment, the real-time yaw angle of the key is obtained based on the IMU, and specifically includes: The DMP of the IMU fuses the nine-axis data output by the IMU to output a quaternion, and the real-time yaw angle of the key is obtained based on the conversion of the quaternion to Euler angle, wherein the real-time yaw angle is represented as:
[0039] wherein represents the real-time yaw angle, the quaternion is a hypercomplex number and is represented as , and after normalization, it satisfies .
[0040] Specifically, the real-time yaw angle of the key is solved based on the original nine-axis data of the IMU, auxiliary information of inertial navigation is introduced for the positioning system, the DMP in the IMU can effectively reduce the data processing load of the main control unit, the original nine-axis data is fused to output a quaternion, and the real-time yaw angle is output based on the conversion of the quaternion to Euler angle.
[0041] The quaternion output by the IMU can obtain Euler angle through specific mathematical conversion, and then obtain the real-time yaw angle of the key. The quaternion is a hypercomplex number and is represented as , and after normalization, it satisfies .
[0042] Euler angle contains yaw angle, pitch angle, roll angle, corresponding to rotation angle around coordinate axis z axis, x axis, y axis, the present application only needs yaw angle data auxiliary, the conversion formula of its quaternion to yaw angle is as follows:
[0043] In the present application, it is assumed that the positive direction of the y axis is the zero point of the yaw angle, that is, the angle between the positive direction of the y axis and the real-time yaw angle is defined as the real-time yaw angle .
[0044] Further, in an embodiment, compared with the real-time yaw angle and the yaw angle, the ambiguous points are eliminated and the real positioning points are retained, and the positioning update of the key is realized, specifically including: The yaw angle between the intersection points before and after the key moves is compared and calculated with the real-time yaw angle: If , the intersection point is a real positioning point, the intersection point is retained, and the intersection point is eliminated, wherein represents a set threshold value, and a reserved error interval; If , the intersection point is a real positioning point, the intersection point is retained, and the intersection point is eliminated.
[0045] Specifically, after the yaw angles and are calculated, the real-time yaw angle is combined, and the IMU yaw angle is used to assist in decision-making to eliminate ambiguous point coordinates. If , it means that the yaw angles calculated by two moving coordinates and the yaw angle measured by the IMU have high confidence, and the point is confirmed as a real positioning point; similarly, if , the point is confirmed as a real positioning point.
[0046] Further, in an embodiment, for the judgment of the movement of the key, specifically: The acceleration data output by the IMU is compared with the preset threshold value to determine whether the key moves.
[0047] Specifically, based on the original acceleration data of the IMU, the threshold value can be set to determine whether the key moves, The coordinate data is updated when the key moves. The acceleration sensor raw data includes x-axis, y-axis and z-axis data. The application is a two-dimensional positioning method, and the acceleration data change of the z-axis is not considered. When the acceleration data of the x-axis or the y-axis is greater than the calibration value, it is judged that the key moves.
[0048] Referring to Figure 3 Fig. 1 is a schematic diagram of the principle of the two-dimensional positioning method based on IMU-UWB double anchor points of the application. When the key moves, the IMU judges that the key moves based on the acceleration data, calculates the relative yaw angle between the intersection coordinates of the two times according to the ranging values of the current time and the last time, and then makes an auxiliary decision according to the yaw angle calculated by the IMU to confirm the real positioning point coordinates, so as to output the positioning coordinates each time the key moves.
[0049] The two-dimensional positioning method based on IMU-UWB double anchor points of the application embodiment fuses the IMU pose data and the UWB ranging data, calculates the relative yaw angle between the intersection coordinates of the two times according to the ranging values of the current time and the last time, and then makes an auxiliary decision according to the yaw angle calculated by the IMU to confirm the real positioning point coordinates, so as to output the positioning coordinates each time the key moves.
[0050] In a second aspect, the application embodiment also provides a two-dimensional positioning device based on IMU-UWB double anchor points.
[0051] In an embodiment, referring to Figure 4 , Figure 4 Fig. 1 is a schematic diagram of the principle of the two-dimensional positioning method based on IMU-UWB double anchor points of the application. When the key moves, the IMU judges that the key moves based on the acceleration data, calculates the relative yaw angle between the intersection coordinates of the two times according to the ranging values of the current time and the last time, and then makes an auxiliary decision according to the yaw angle calculated by the IMU to confirm the real positioning point coordinates, so as to output the positioning coordinates each time the key moves. Figure 4 As shown in Fig. 1, the two-dimensional positioning device based on IMU-UWB double anchor points includes an information acquisition module, a calculation module and a positioning information display module.
[0052] The information acquisition module is used to measure the distance between the key and the two anchor points based on the UWB technology, and to obtain the real-time yaw angle of the key based on the IMU. In actual application, the UWB chip is responsible for distance information acquisition, and the IMU chip is responsible for yaw angle information and acceleration information acquisition.
[0053] The calculation module is used to construct two distance circles with the distance as the radius based on the distance data and real-time yaw angle data obtained by the information acquisition module, calculate the intersection of the two distance circles, obtain the true positioning point and the fuzzy point, and determine the yaw angle between the intersection points before and after the key is moved based on the intersection point and the corresponding intersection point calculated again after the key is moved. It also compares the real-time yaw angle with the yaw angle, eliminates the fuzzy point, and retains the true positioning point. In actual applications, the STM32 microcontroller collects distance information and IMU data through SPI or IIC communication, and further calculates to ultimately obtain the positioning coordinates.
[0054] The positioning information display module is used to display the key's location based on the actual positioning point data. In actual applications, the STM32 microcontroller uploads key information such as positioning coordinates to a display terminal, such as a PC, through serial communication, thereby displaying the positioning coordinates in real time.
[0055] On the third aspect, an embodiment of the present application provides a dual-anchor two-dimensional positioning device based on IMU-UWB. The dual-anchor two-dimensional positioning device based on IMU-UWB can be a personal computer (PC), a laptop, a server, or other device with data processing capabilities.
[0056] Reference Figure 5 , Figure 5 The hardware structure diagram of the dual-anchor 2D positioning device based on IMU-UWB involved in the embodiment of the present application is shown in FIG. In the embodiment of the present application, the dual-anchor 2D positioning device based on IMU-UWB may include a processor, a memory, a communication interface, and a communication bus.
[0057] The communication bus may be of any type and is used to interconnect the processor, memory, and communication interface.
[0058] Communication interfaces include input / output (I / O), physical, and logical interfaces, which interconnect components within the IMU-UWB-based dual-anchor 2D positioning device and connect it to other devices (such as other computing devices or user devices). Physical interfaces can include Ethernet, fiber, or ATM interfaces; user devices can include displays and keyboards.
[0059] The memory can be various types of storage media, such as random access memory (RAM), read-only memory (ROM), non-volatile RAM (NVRAM), flash memory, optical storage, hard disk, programmable ROM (PROM), erasable PROM (EPROM), electrically erasable PROM (EEPROM), and the like.
[0060] The processor can be a general-purpose processor, which can invoke the IMU-UWB-based double-anchor point two-dimensional positioning program stored in the memory and execute the IMU-UWB-based double-anchor point two-dimensional positioning method provided in the embodiments of the present application. For example, the general-purpose processor can be a central processing unit (CPU). The method executed when the IMU-UWB-based double-anchor point two-dimensional positioning program is invoked can refer to various embodiments of the IMU-UWB-based double-anchor point two-dimensional positioning method of the present application, which will not be described here.
[0061] Those skilled in the art can understand that Figure 5 The hardware structure shown in the foregoing figures does not constitute a limitation on the present application, and can include more or fewer components than those shown, or combine certain components, or different arrangement of components.
[0062] The terms “include” and “have” and any variations thereof in the specification and claims of the present application and the foregoing drawings are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the listed steps or units, but can optionally include steps or units not listed, or can optionally include other steps or units inherent to these processes, methods, products, or devices. The terms “first”, “second”, and “third” and the like descriptions are used to distinguish different objects, and do not represent the order or limit the types of “first”, “second”, and “third”.
[0063] In the description of the embodiments of the present application, “exemplary”, “for example”, “for instance” or “such as” are used to represent an example, illustration, or description. Any embodiment or design scheme described as “exemplary”, “for example”, or “for instance” in the embodiments of the present application should not be interpreted as more preferred or more advantageous than other embodiments or design schemes. Rather, the words “exemplary”, “for example”, or “for instance” are intended to present the relevant concept in a specific manner.
[0064] In the description of the embodiments of the present application, unless otherwise specified, " / " means the meaning of or, for example, A / B can mean A or B; the text "and / or" only describes the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which can represent: A exists alone, A and B exist together, and B exists alone, and in addition, in the description of the embodiments of the present application, "multiple" means two or more than two.
[0065] In some of the processes described in the embodiments of the present application, a plurality of operations or steps are included in a specific order, but it should be understood that these operations or steps can be executed or in parallel without the order in which they appear in the embodiments of the present application, and the serial number of the operation is only used to distinguish different operations, and the serial number itself does not represent any execution order. In addition, these processes can include more or fewer operations, and these operations or steps can be executed in sequence or in parallel, and these operations or steps can be combined.
[0066] From the above description of the embodiments, those skilled in the art can clearly understand that the above-mentioned embodiment method can be realized by means of software and the necessary general hardware platform, of course, it can also be realized by hardware, but in many cases the former is a better embodiment. Based on such understanding, the technical solutions of the present application can be embodied in the form of a software product, which is stored in a storage medium (such as a ROM / RAM, a magnetic disk, an optical disk) as described above, and includes a plurality of instructions for making a terminal device execute the method described in each embodiment of the present application.
[0067] The above is only the preferred embodiment of the present application, and does not limit the patent scope of the present application, and any equivalent structure or equivalent process transformation using the content of the present application specification and drawings, or direct or indirect application in other related technical fields, are also included in the patent protection scope of the present application.
Claims
1. A dual-anchor two-dimensional positioning method based on IMU-UWB, characterized in that: The dual-anchor two-dimensional positioning method based on IMU-UWB includes: Based on UWB technology, the distance between the key and the two anchor points is measured, and two distance circles are constructed with the distance as the radius. The intersection of the two distance circles is calculated to obtain the true positioning point and the fuzzy point. Determining the yaw angle between the intersection points before and after the key is moved based on the intersection point and the corresponding intersection point calculated again after the key is moved; The real-time yaw angle of the key is obtained based on the IMU, and the real-time yaw angle is compared with the yaw angle to eliminate fuzzy points and retain the real positioning points to achieve the key positioning update.
2. The dual-anchor two-dimensional positioning method based on IMU-UWB according to claim 1, characterized in that: The method of measuring the distance between the key and the two anchor points based on UWB technology, constructing two distance circles with the distance as the radius, calculating the intersection of the two distance circles, and obtaining the true positioning point and the fuzzy point specifically includes: The distance between the key and the first anchor point, and the distance between the key and the second anchor point are obtained by using the bilateral two-way ranging method based on UWB technology; A distance circle is constructed with the first anchor point as the center and the distance between the key and the first anchor point as the radius; a distance circle is constructed with the second anchor point as the center and the distance between the key and the second anchor point as the radius; The intersection of the two distance circles is calculated, and one of the intersection points is the true positioning point and the other is the fuzzy point.
3. The dual-anchor two-dimensional positioning method based on IMU-UWB according to claim 2, characterized in that: For the distance circle corresponding to the first anchor point, it is expressed as: in, represents the horizontal coordinate of the key, Represents the vertical coordinate of the key. The first anchor point is located at the center of the coordinate system. The coordinates are expressed as , Indicates the distance between the key and the first anchor point; For the distance circle corresponding to the second anchor point, it is expressed as: in, Represents the distance between the first anchor point and the second anchor point, and the coordinates of the second anchor point are , Indicates the distance between the key and the second anchor point; For the intersection of two distance circles, it is expressed as: 。 4. The dual-anchor two-dimensional positioning method based on IMU-UWB according to claim 1, characterized in that: The determining of the yaw angle between the intersection points before and after the key is moved based on the intersection point and the corresponding intersection point calculated again after the key is moved specifically includes: Get the intersection point calculated before the key moves 、 , and the corresponding intersection calculated after the key moves 、 ; Calculate the intersection point Intersection The yaw angle between them, and the intersection point Intersection Yaw angle between.
5. The dual-anchor two-dimensional positioning method based on IMU-UWB according to claim 4, characterized in that: For the intersection Intersection The yaw angle between in, Indicates the intersection Intersection The yaw angle between 、 、 Indicates the intermediate quantity, , , ; For the intersection Intersection The yaw angle between in, Indicates the intersection Intersection The yaw angle between .
6. The dual-anchor two-dimensional positioning method based on IMU-UWB according to claim 4, characterized in that: The real-time yaw angle of the key is obtained based on the IMU, specifically including: The DMP of the IMU fuses the nine-axis data of the IMU and outputs a quaternion. Based on the method of converting the quaternion into Euler angles, the real-time yaw angle of the key is obtained. The real-time yaw angle is expressed as: in, Represents the real-time yaw angle. Quaternion is a hypercomplex number, expressed as , and after normalization, it satisfies .
7. The dual-anchor two-dimensional positioning method based on IMU-UWB according to claim 4, characterized in that: The comparing the real-time yaw angle with the yaw angle, eliminating fuzzy points and retaining true positioning points, and implementing key positioning update specifically includes: Compare the yaw angle between the intersection points before and after the key is moved with the real-time yaw angle: like , then the intersection For the real positioning point, keep the intersection point , remove intersection points ,in, Indicates setting threshold; like , then the intersection For the real positioning point, keep the intersection point , remove intersection points .
8. The dual-anchor two-dimensional positioning method based on IMU-UWB according to claim 4, characterized in that: For the judgment of key movement, specifically: The acceleration data output by the IMU is compared with the preset threshold to determine whether the key has moved.
9. A dual-anchor two-dimensional positioning device based on IMU-UWB, characterized in that: The IMU-UWB-based dual-anchor two-dimensional positioning device includes: An information acquisition module, which is used to measure the distance between the key and two anchor points based on UWB technology, and obtain the key's real-time yaw angle based on the IMU; a calculation module, configured to construct two distance circles with the distance as the radius based on the distance data and the real-time yaw angle data obtained by the information acquisition module, calculate the intersection of the two distance circles to obtain a true positioning point and an ambiguous point, determine the yaw angle between the intersection points before and after the key is moved based on the intersection point and the intersection point calculated again after the key is moved, and compare the real-time yaw angle with the yaw angle to eliminate the ambiguous point and retain the true positioning point; The positioning information display module is used to display the positioning of the key based on the real positioning point data.
10. A dual-anchor two-dimensional positioning device based on IMU-UWB, characterized in that: The IMU-UWB-based dual-anchor two-dimensional positioning device includes a processor, a memory, and an IMU-UWB-based dual-anchor two-dimensional positioning program stored in the memory and executable by the processor, wherein when the IMU-UWB-based dual-anchor two-dimensional positioning program is executed by the processor, the steps of the IMU-UWB-based dual-anchor two-dimensional positioning method according to any one of claims 1 to 8 are implemented.