Indoor / Outdoor Switching Positioning Method and System Based on Multi-Sensor Input Fusion

Abstract

This invention relates to an indoor / outdoor switching positioning method and system based on multi-sensor input fusion. The invention first determines whether the current location information contains a GPS signal. If a GPS signal is present, RTK real-time differential positioning is used for positioning; otherwise, laser SLAM positioning is used. During laser SLAM positioning, it continuously checks whether QR code information is detected. If a QR code is detected, positioning is based on the QR code information. If no QR code is detected, it determines whether the current scene is outdoors. If outdoors, RTK real-time differential positioning is used; otherwise, laser SLAM positioning is used. This achieves the goal of applying different positioning schemes according to different areas. Furthermore, through seamless switching between positioning schemes, the system's integration can be improved while maintaining positioning accuracy.

Description

Technical Field

[0001] This invention relates to the field of switching positioning technology, and in particular to an indoor / outdoor switching positioning method and system based on multi-sensor input fusion. Background Technology

[0002] Currently, there are relatively mature solutions for both indoor and outdoor positioning. When mobile robots are positioned indoors, they often use methods such as laser SLAM (Simultaneous Localization and Mapping), visual SLAM, or QR codes for positioning.

[0003] SLAM requires matching the currently identified feature points with feature points in a pre-built map, then obtaining depth information from the point cloud to calculate the robot's location on the map. This method needs a sufficient amount of feature information for matching to improve the confidence level of localization accuracy. In outdoor environments, especially in the wild, the terrain is complex and varied, so SLAM methods often lose localization information in outdoor environments, resulting in relatively low reliability.

[0004] The QR code needs to be scanned by a camera to obtain the position of the QR code relative to the camera, and then the position information of the current mobile robot is obtained through coordinate transformation. However, the robot is affected by motion and camera perspective during movement, and often fails to scan the QR code, resulting in missing positioning information and limited applicability.

[0005] Due to the limitations of SLAM outdoors, GPS (Global Positioning System) is often used for positioning outdoors. However, GPS positioning accuracy is often insufficient to meet the level required for navigation. Therefore, RTK (Real-time kinematic) carrier phase differential technology is also needed to achieve centimeter-level positioning accuracy. However, indoors, walls can weaken satellite signals or even cause the connection to be lost, making differential calculation impossible.

[0006] Based on the above description, the limitations of GPS positioning indoors and the limitations of laser SLAM outdoors mean that when mobile robots need to work alternately indoors and outdoors, a single positioning scheme cannot be used alone. The method of achieving fusion positioning by filtering data from various sensors using a Kalman filter is currently the mainstream method for multi-sensor fusion positioning, but its implementation is relatively complex and requires a deep understanding of the performance of each sensor and the characteristics of data noise (e.g., Chinese patent document CN202010840047.4). Furthermore, positioning switching achieved through inertial navigation methods depends on the measurement accuracy of the inertial measurement unit (IMU) (e.g., Chinese patent document CN202010993315.6). The positioning information calculated by the inertial measurement unit (IMU) will accumulate errors, which will increase over time. Summary of the Invention

[0007] To address the aforementioned problems in the existing technology, this invention provides an indoor / outdoor switching positioning method and system based on multi-sensor input fusion.

[0008] To achieve the above objectives, the present invention provides the following solution:

[0009] An indoor / outdoor switching positioning method based on multi-sensor input fusion includes:

[0010] Get the current location information;

[0011] Determine whether the current point's location information contains a GPS signal to obtain a first determination result;

[0012] When the first determination result indicates that the GPS signal is included, the RTK real-time differential positioning method is used for positioning.

[0013] When the first determination result is that the GPS signal is not included, the laser SLAM positioning method is used for positioning.

[0014] During the positioning process using the laser SLAM positioning method, it is determined in real time whether the QR code information is recognized, and a second judgment result is obtained.

[0015] When the second judgment result indicates that QR code information has been identified, the location is determined based on the QR code information;

[0016] If the second judgment result is that no QR code information is recognized, then determine whether the current scene is outdoors to obtain the third judgment result;

[0017] When the third determination result indicates that the current scene is outdoors, the RTK real-time differential positioning method is used for positioning.

[0018] When the third judgment result indicates that the current scene is not outdoors, the laser SLAM positioning method is used for positioning.

[0019] Preferably, before obtaining the location information of the current point, the method further includes:

[0020] The current scene is constructed as a grid map using LiDAR.

[0021] Preferably, after constructing a raster map of the current scene using LiDAR, the method further includes:

[0022] The station-centric coordinate system corresponding to the raster map is constructed with the initial mapping point as the origin and due north as the positive direction of the x-axis.

[0023] Preferably, during the positioning process using the RTK real-time differential positioning method, the current point's location information is converted into station center coordinates corresponding to the grid map.

[0024] Preferably, the location information of the current point is converted into station-centric coordinates corresponding to the grid map, specifically including:

[0025] Get the latitude and longitude of the current point and the latitude and longitude of the origin in the raster map;

[0026] Convert the latitude and longitude of the origin of the coordinate system in the raster map to radians;

[0027] The transformation matrix from the geocentric coordinate system to the station-centric coordinate system is determined based on the aforementioned radian system.

[0028] Based on the transformation matrix, the location information of the current point is converted into the station coordinates corresponding to the grid map.

[0029] Preferably, the location information of the current point is converted into station-centric coordinates corresponding to the grid map, specifically including:

[0030] Determine the coordinates of the current point in the Earth-centered Earth-fixed coordinate system based on the current point's location information;

[0031] Determine the position of the current point in the geocentric coordinate system relative to the coordinate origin of the raster map in the geocentric coordinate system;

[0032] Based on the coordinates, the current point's location coordinates are converted into the corresponding station center coordinates on the raster map.

[0033] Preferably, during the positioning process based on the QR code information, the ROS_AprilTag function package is used to obtain the QR code information, and the positioning information of the current point is calculated based on the QR code information; the QR code information includes the location information of the QR code.

[0034] According to specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0035] This invention provides an indoor / outdoor switching positioning method based on multi-sensor input fusion. It determines whether the current location information contains a GPS signal. If a GPS signal is present, RTK real-time differential positioning is used for positioning; otherwise, laser SLAM positioning is used. During laser SLAM positioning, it continuously checks whether QR code information is detected. If a QR code is detected, positioning is performed based on the QR code. If no QR code is detected, it determines whether the current scene is outdoors. If the scene is outdoors, RTK real-time differential positioning is used; otherwise, laser SLAM positioning is used. This allows for the application of different positioning schemes depending on the location, and seamless switching between positioning schemes improves system integration while maintaining positioning accuracy.

[0036] Corresponding to the above-mentioned indoor / outdoor switching positioning method based on multi-sensor input fusion, the present invention also provides an indoor / outdoor switching positioning system based on multi-sensor input fusion, the system comprising: a sensing module, a processor, and a memory;

[0037] Both the memory and the sensing module are connected to the processor; the sensing module is used to acquire the location information of the current point; the memory stores a computer software program; the computer software program is used to implement the above-mentioned indoor / outdoor switching positioning method based on multi-sensor input fusion; the processor is used to execute the computer software program based on the location information of the current point.

[0038] Since the technical effects achieved by the indoor / outdoor switching positioning system based on multi-sensor input fusion provided by this invention are the same as those achieved by the indoor / outdoor switching positioning method based on multi-sensor input fusion provided above, they will not be described again here. Attached Figure Description

[0039] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0040] Figure 1 This is an implementation framework diagram of the indoor / outdoor switching positioning method based on multi-sensor input fusion provided by the present invention;

[0041] Figure 2 This is a schematic diagram of the geocentric coordinate system provided in an embodiment of the present invention;

[0042] Figure 3 This is a flowchart of switching latitude and longitude to the geocentric coordinate system provided in an embodiment of the present invention;

[0043] Figure 4 This is a flowchart of switching from a geocentric coordinate system to a raster map coordinate system, provided in an embodiment of the present invention.

[0044] Figure 5 This is a schematic diagram of the positioning and switching coordinate system provided in an embodiment of the present invention;

[0045] Figure 6 A flowchart for creating a raster map using SLAM provided in an embodiment of the present invention;

[0046] Figure 7 This is a schematic diagram of the camera perspective provided in an embodiment of the present invention;

[0047] Figure 8 This is a schematic diagram of the structure of the indoor / outdoor switching positioning system based on multi-sensor input fusion provided by the present invention. Detailed Implementation

[0048] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0049] The purpose of this invention is to provide an indoor / outdoor switching positioning method and system based on multi-sensor input fusion, which enables seamless switching between various positioning schemes, thereby improving the system integration while ensuring positioning accuracy.

[0050] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0051] The indoor / outdoor switching positioning method based on multi-sensor input fusion provided by this invention includes:

[0052] Step 100: Obtain the current location information.

[0053] Step 101: Determine whether the current location information contains a GPS signal to obtain the first determination result.

[0054] Step 102: When the first judgment result is that GPS signal is included, the RTK real-time differential positioning method is used for positioning.

[0055] Step 103: When the first judgment result is that there is no GPS signal, the laser SLAM positioning method is used for positioning.

[0056] Step 104: During the positioning process using the laser SLAM positioning method, determine in real time whether the QR code information is recognized, and obtain the second judgment result.

[0057] Step 105: When the second judgment result is that the QR code information is recognized, locate the location based on the QR code information.

[0058] Step 106: When the second judgment result is that the QR code information is not recognized, determine whether the current scene is outdoors, and obtain the third judgment result.

[0059] Step 107: When the third judgment result indicates that the current scene is outdoors, the RTK real-time differential positioning method is used for positioning.

[0060] Step 108: When the third judgment result indicates that the current scene is not outdoors, use the laser SLAM positioning method for positioning.

[0061] The above implementation process is simplified as follows: Figure 1 As shown.

[0062] To further improve the accuracy and real-time performance of positioning, the indoor / outdoor switching positioning method based on multi-sensor input fusion provided by this invention further includes the following step before proceeding to step 100:

[0063] The current scene is constructed as a grid map using LiDAR.

[0064] The station-centric coordinate system corresponding to the raster map is constructed with the starting mapping point as the origin and due north as the positive direction of the x-axis.

[0065] Based on the constructed station-centric coordinates, during the positioning process using the RTK real-time differential positioning method, the current point's location information is converted into station-centric coordinates corresponding to the raster map. For example... Figure 5As shown, converting the current point's location information into station-centric coordinates on the raster map is mainly achieved through two methods. One method involves obtaining the latitude and longitude of the current point and the latitude and longitude of the origin in the raster map. The latitude and longitude of the origin in the raster map are then converted to radians. Based on the radians, a transformation matrix from the geocentric coordinate system to the station-centric coordinate system is determined. Based on this transformation matrix, the current point's location information is converted into station-centric coordinates on the raster map. The other method involves determining the current point's coordinates in the geocentric coordinate system based on its location information. The coordinates of the current point in the geocentric coordinate system are determined relative to the origin in the raster map. Based on this coordinate position, the current point's location coordinates are converted into station-centric coordinates on the raster map.

[0066] In the process of locating based on QR code information, this invention mainly uses the ROS_AprilTag package to obtain the QR code information and then calculates the current location information based on the QR code information. The QR code information includes the location information of the QR code.

[0067] The following example illustrates the specific implementation process of the indoor / outdoor switching positioning method based on multi-sensor input fusion.

[0068] Example 1

[0069] In this embodiment, a method of dividing the positioning interval is used to achieve seamless switching between RTK and laser SLAM positioning. A QR code guidance method is used to address the shortcomings of laser SLAM in confined spaces caused by the blind spot of the lidar. The SLAM algorithm used is the ROS open-source Gmapping algorithm. Gmapping locates the robot by identifying and matching feature points through laser point clouds. Therefore, this algorithm relies on extracting feature information from the environment. If the feature objects are insufficient to provide enough confidence for positioning, it will severely affect the positioning accuracy.

[0070] In this embodiment, the RTK positioning information used can be directly obtained from the GNSS integrated navigation device. According to the protocol output by the GNSS navigation device, the latitude, longitude and heading angle of the corresponding location are extracted. When the number of satellites received by the GNSS antenna is large, the obtained positioning information is more accurate. However, when the mobile robot is indoors, the received satellite signal is affected by the wall, and the positioning will be greatly affected.

[0071] In this embodiment, the QR code positioning method used is the open-source AprilTag QR code positioning method. The QR code adopts the TAG36H11 family. There are 587 families of TAG36H11, each with a corresponding ID from 0 to 586. After the camera recognizes the QR code, it can obtain the positioning information of the QR code relative to the camera.

[0072] Based on the above settings, when switching positioning methods, it is essential to ensure that the coordinate transformations of various positioning schemes are within the same coordinate system. This embodiment converts the latitude and longitude information acquired by RTK into x, y, yaw values ​​in the rectangular coordinate system of the raster map. By calibrating the latitude, longitude, and azimuth of a point, coordinate system unification is achieved. In the process of converting latitude and longitude information into rectangular coordinates, the method used is to first convert the latitude and longitude to rectangular coordinates in the geocentric coordinate system, such as... Figure 2 As shown, the Earth-Centered, Earth-Fixed (ECEF) coordinate system is a Cartesian coordinate system with the Earth's center as its origin. The origin O (0,0,0) is the Earth's center of mass. The z-axis is parallel to the Earth's axis and points towards the North Pole. The x-axis points towards the intersection of the Prime Meridian and the equator. The y-axis is perpendicular to the xOz plane (the intersection of 90°E and the equator), forming a right-handed coordinate system. In this embodiment, the ECEF uses the WGS84 coordinate system. The x and y planes defined in the WGS84 coordinate system are perfect circles with a radius of 6378137. The xz or yz circles are ellipses with a z-axis radius of 6356752.3142451793.

[0073] The specific implementation process of switching latitude and longitude to the Earth-centered Earth-fixed coordinate system is as follows: Figure 3 As shown, specifically:

[0074] When converting coordinates from the Earth-centered, Earth-fixed coordinate system to the coordinate system of the grid map where the laser positioning is located, calibration is required first, based on a point. In this embodiment, the origin (0, 0) of the laser positioning coordinates and the due north direction will be used as the calibration point. For convenience, when the laser radar performs mapping, mapping will begin from the boundary between indoor and outdoor areas. This location ensures the accuracy of the laser radar positioning and also allows for the acquisition of RTK positioning information. Using the heading angle information obtained from RTK, the mobile robot is aligned with the due north direction before mapping begins. During the mapping process, the starting mapping point will be used as the coordinate origin, and the forward direction will be the positive x-axis. Based on this, this embodiment uses the starting point position (x, y, yaw) as (0, 0, 0) and records the latitude and longitude coordinates through the information returned by RTK, which are then input into the program for calibration.

[0075] The specific implementation process for switching from the geocentric coordinate system to raster map coordinates (i.e., the station-centered coordinate system) is as follows: Figure 4 As shown. After completing the coordinate system calibration, through... Figure 4 The two algorithms shown can convert the acquired RTK information into station-centric coordinates corresponding to the grid map, so that RTK and LiDAR positioning are in the same coordinate system.

[0076] Taking the example of a mobile robot returning to its indoor charging station, the unified coordinate system is as follows: Figure 5 As shown. The mobile robot maps the area at the entrance, which also serves as a location switching point. After entering the building, it switches to LiDAR for point cloud matching to achieve localization. When the robot needs to enter the charging compartment to dock with the charging station, due to the limited space, it first uses LiDAR to locate itself and walk to the charging station. Figure 5 At the first QR code outside the charging station shown, after recognizing the first QR code, the mobile robot will obtain the positioning information corresponding to the first QR code and use the position of the first QR code as the new origin of the coordinate system, switching to a new positioning.

[0077] When switching to QR code positioning, the ROS_AprilTag package can be used to obtain information such as x, y, z, roll, pitch, yaw, and ID of the currently scanned QR code. Therefore, different QR codes have different locations, and the robot's current position can be calculated from these locations. For example, if the first QR code, with ID 0, is taken as the origin of the coordinate system (x, y, yaw = (0, 0, 0)), and the QR codes with ID 1 and ID 0 have moved 15cm along the x-axis of the coordinate system, then when the QR code with ID 1 is detected, the robot's current position (X, Y, Yaw) is calculated by obtaining the x, y, and yaw values ​​relative to the QR code with ID 1. The specific calculation method is as follows:

[0078] X = tag_ID * 0.15 + y;

[0079] Y = x;

[0080] Yaw = yaw / 180*PI.

[0081] Example 2

[0082] To achieve seamless switching of location information in practical applications, the specific implementation steps of this embodiment are as follows:

[0083] Step 1: Place the mobile robot in such a location Figure 5 The indoor-outdoor boundary position shown is directly in front of the mobile robot, that is, the x-axis of its own coordinate system is aligned with due north. Due north can be determined by the latitude, longitude and azimuth information transmitted back by RTK, and the latitude, longitude and azimuth information can be recorded.

[0084] Step Two: Starting from the initial position, open the mapping program of the LiDAR localization software. Use a remote control or other controller to guide the mobile robot into the indoor area, circle the area, and finally return to the initial position. Convert the acquired point cloud image into a raster map, and use a drawing tool to optimize the raster map, such as... Figure 6 As shown.

[0085] Step 3: After completing the mapping, SLAM can be used for navigation, moving the mobile robot to locations such as... Figure 7 The four positions ABCD shown are obtained, and the positioning information of these four positions is used to realize the positioning switch, which are recorded as A(x1,y1), B(x2,y2), C(x3,y3) and D(x4,y4) respectively.

[0086] Step 4: Place QR codes on the ground in the area where they will be used for positioning. The size and spacing of the QR codes should be determined based on the height of the mobile robot's camera from the ground and its viewing angle. Specifically, first determine the QR code size based on its height from the ground; the greater the height, the larger the QR code. Use the formula L = 0.02 + (3*h) / 10 to determine the side length of the QR code, where L is the side length of the QR code and h is the height of the camera from the ground. For example, when the robot's camera is 0.5m from the ground, the side length of the QR code is 0.17m. The center distance of the QR codes is positively correlated with the camera's viewing angle and height from the ground. When the viewing angle is u, such as... Figure 7 As shown, the camera scans two QR codes at the same time. At this time, only one QR code can be used as the reference. Therefore, during the movement of the mobile robot, it is necessary to set the center distance between the two QR codes so that when the current QR code is missing in the field of vision, the next QR code will appear in the field of vision. Based on this, the center distance C between the two QR codes is set as C = h * tan(u / 2) * 2 - L.

[0087] Step 5: Start the positioning program. First, determine whether there is an RTK signal. If there is an RTK signal, it means that the current location is outdoors, and RTK positioning can be used directly. If there is no signal, determine whether the QR code recognition returns QR code positioning information. If QR code positioning is returned, QR code positioning can be used directly; otherwise, LiDAR positioning is used.

[0088] Step Six: During the positioning switching process, the switching between laser positioning and RTK positioning is achieved by calibrating both to the same coordinate system and then determining the positioning coordinates, such as... Figure 7 As shown, if the camera does not recognize the QR code, the coordinates are determined to be indoors if they are within ABCD, and outdoors if they are outside ABCD. The determination method is as follows: the current coordinate value (x0, y0) obtained by RTK positioning or LiDAR positioning is input into the determination program. If the following formula is satisfied, it can be determined to be indoors; otherwise, it is outdoors, thus realizing the location switching.

[0089]

[0090]

[0091]

[0092]

[0093] Step 7: The switch between laser positioning and QR code positioning is determined by detecting whether the camera recognizes the QR code. When the QR code is recognized, the information of the QR code is obtained and QR code positioning is used. When the QR code is not recognized, laser radar positioning is used.

[0094] Based on the above description, the present invention has the following advantages compared to the prior art:

[0095] 1. This invention achieves the purpose of applying different positioning schemes according to different regions by unifying the coordinate system under the grid map. Furthermore, by seamlessly switching between positioning schemes, it ensures positioning accuracy while improving the system integration.

[0096] 2. When using an indoor SLAM positioning solution, if it is necessary to enter a narrow and enclosed space, the blind zone of the lidar (generally 30-40cm) will prevent the lidar from achieving positioning when passing through the narrow box. In this case, the present invention switches to QR code positioning, and the positioning accuracy can reach the millimeter level, which solves the shortcomings of SLAM positioning in narrow and enclosed spaces.

[0097] 3. Regarding the determination of critical values ​​during the positioning switching process, this invention adopts a method of dividing the positioning interval after unifying the positioning coordinate system and a method of switching the positioning mode after recognizing the QR code, which realizes seamless switching between different sensor positioning and solves the problem of positioning loss or reuse of two positioning information due to inaccurate timing of switching in traditional methods.

[0098] Furthermore, corresponding to the above-mentioned indoor / outdoor switching positioning method based on multi-sensor input fusion, this invention also provides an indoor / outdoor switching positioning system based on multi-sensor input fusion, such as... Figure 8 As shown, the system includes: a sensing module 1, a processor 2, and a memory 3.

[0099] Both the memory 3 and the sensing module 1 are connected to the processor 2. The sensing module 1 is used to acquire the location information of the current point. The memory 3 stores a computer software program. The computer software program is used to implement the indoor / outdoor switching positioning method based on multi-sensor input fusion provided above. The processor 2 is used to execute the computer software program based on the location information of the current point.

[0100] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the systems disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple; relevant parts can be referred to the method section.

[0101] This document uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. Furthermore, those skilled in the art will recognize that, based on the ideas of the present invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A method for indoor / outdoor switching positioning based on multi-sensor input fusion, characterized in that, include: The current scene is constructed as a grid map using LiDAR; Using the initial mapping point as the origin and the north direction as the positive x-axis, construct the station-centric coordinate system corresponding to the raster map; Get the current location information; Determine whether the current point's location information contains a GPS signal to obtain a first determination result; When the first determination result is that the GPS signal is included, the RTK real-time differential positioning method is used for positioning; during the positioning process using the RTK real-time differential positioning method, the location information of the current point is converted into the station center coordinates corresponding to the grid map; When the first determination result is that the GPS signal is not included, the laser SLAM positioning method is used for positioning. During the positioning process using the laser SLAM positioning method, it is determined in real time whether the QR code information is recognized, and a second judgment result is obtained. When the second judgment result indicates that QR code information has been identified, the location is determined based on the QR code information; When the second judgment result is that no QR code information is recognized, the third judgment result is obtained by judging whether the current scene is outdoors. The judgment method is as follows: the current coordinate value (x0, y0) obtained by RTK positioning or LiDAR positioning is input into the judgment program. If the following formula is satisfied, it can be judged as indoors; otherwise, it is outdoor. In the formula, (x1,y1), (x2,y2), C(x3,y3) and (x4,y4) represent the positioning information of the four positions A, B, C and D, respectively; When the third determination result indicates that the current scene is outdoors, the RTK real-time differential positioning method is used for positioning. When the third judgment result indicates that the current scene is not outdoors, the laser SLAM positioning method is used for positioning. To determine the critical value during the positioning switching process, a method of dividing the positioning interval after unifying the positioning coordinate system and a method of switching the positioning mode after recognizing the QR code are adopted to achieve seamless switching between positioning of different sensors.

2. The indoor / outdoor switching positioning method based on multi-sensor input fusion according to claim 1, characterized in that, Convert the current point's location information into the corresponding station-centric coordinates on the raster map, specifically including: Get the latitude and longitude of the current point and the latitude and longitude of the origin in the raster map; Convert the latitude and longitude of the origin of the coordinate system in the raster map to radians; The transformation matrix from the geocentric coordinate system to the station-centric coordinate system is determined based on the aforementioned radian system. Based on the transformation matrix, the location information of the current point is converted into the station coordinates corresponding to the grid map.

3. The indoor / outdoor switching positioning method based on multi-sensor input fusion according to claim 1, characterized in that, Convert the current point's location information into the corresponding station-centric coordinates on the raster map, specifically including: Determine the coordinates of the current point in the Earth-centered Earth-fixed coordinate system based on the current point's location information; Determine the position of the current point in the geocentric coordinate system relative to the coordinate origin of the raster map in the geocentric coordinate system; Based on the coordinates, the current point's location coordinates are converted into the corresponding station center coordinates on the raster map.

4. The indoor / outdoor switching positioning method based on multi-sensor input fusion according to claim 1, characterized in that, During the location process based on the QR code information, the ROS_AprilTag package is used to obtain the QR code information, and the location information of the current point is calculated based on the QR code information; the QR code information includes the location information of the QR code.

5. An indoor / outdoor switching positioning system based on multi-sensor input fusion, characterized in that, include: Sensing module, processor, and memory; Both the memory and the sensing module are connected to the processor; The sensing module is used to acquire the location information of the current point; the memory stores a computer software program; the computer software program is used to implement the indoor / outdoor switching positioning method based on multi-sensor input fusion as described in any one of claims 1-4; the processor is used to execute the computer software program based on the location information of the current point.

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