UWB-based unmanned vehicle positioning method and terminal

Abstract

The invention provides a UWB-based unmanned vehicle positioning method and terminal, and the method comprises the steps: judging whether a vehicle with a vehicle-mounted UWB tag enters a preset space or not, deploying a plurality of UWB base stations in a square array in the preset space, and enabling the distances between the transversely and longitudinally adjacent UWB base stations to be equal; when the vehicle runs into the preset space, the course angle of the vehicle is calculated in real time; two UWB base stations which are perpendicular to the course angle or one component of the course angle and are closest to the vehicle in the square array are selected according to the course angle, and GPS position information of the current vehicle is determined through the two UWB base stations. According to the method, the reference UWB base station for positioning the vehicle can be selected in real time in the vehicle driving process, and the minimum vehicle positioning error of the selected UWB base station is ensured, so that the problem of unmanned driving of the vehicle in a wide-range open field and a dusty road surface due to unobvious surrounding environment characteristics is solved, and unmanned driving of the vehicle can be ensured to be realized with maximum precision.

Description

Technical Field

[0001] The present invention relates to the technical field of unmanned vehicle, and in particular to an unmanned vehicle positioning method and terminal based on UWB. Background Art

[0002] Currently, the method for vehicles to achieve unmanned driving by repeatedly driving along a trajectory in open areas, dusty roads, and in areas with unclear surrounding features is generally based on GPS navigation, but unmanned driving is not possible in the absence of GPS signals.

[0003] In response to the problem of missing GPS signals, there are currently solutions to achieve unmanned driving based on the ranging principle of UWB (ultra-wideband) technology. However, the UWB ranging range is short, with a conventional test distance of about 500m, which is suitable for indoor positioning. As the communication distance increases, the ranging accuracy will decrease, and the real-time performance will decrease. For unmanned driving with a wide range, such as 5km×5km, there is currently no effective solution. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a UWB-based unmanned vehicle positioning method and terminal to solve the problem of unmanned driving of vehicles in wide open areas and dusty roads with unclear surrounding environment features, and ensure that the vehicle can achieve unmanned driving with maximum accuracy.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is: A UWB-based unmanned vehicle positioning method comprises the following steps: S1. Determine whether the vehicle enters a preset space, wherein a plurality of UWB base stations are deployed in a square array in the preset space, wherein the distances between the UWB base stations adjacent in the horizontal and vertical directions are equal, and the vehicle carries an on-board UWB tag; S2. When the vehicle enters the preset space, calculating the heading angle of the vehicle in real time; S3. Select two UWB base stations in the square array that are perpendicular to the heading angle or one component of the heading angle and closest to the vehicle according to the heading angle, and use the two UWB base stations to determine the current GPS position information of the vehicle.

[0006] In order to solve the above technical problems, another technical solution adopted by the present invention is: A UWB-based unmanned vehicle positioning terminal includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the following steps when executing the computer program: S1. Determine whether the vehicle enters a preset space, wherein a plurality of UWB base stations are deployed in a square array in the preset space, wherein the distances between the UWB base stations adjacent in the horizontal and vertical directions are equal, and the vehicle carries an on-board UWB tag; S2. When the vehicle enters the preset space, calculating the heading angle of the vehicle in real time; S3. Select two UWB base stations in the square array that are perpendicular to the heading angle or one component of the heading angle and closest to the vehicle according to the heading angle, and use the two UWB base stations to determine the current GPS position information of the vehicle.

[0007] The beneficial effects of the present invention are as follows: the present invention provides a UWB-based unmanned vehicle positioning method and terminal, which realizes real-time positioning of unmanned vehicles traveling in the preset space by deploying a square UWB base station array in a preset space and using multiple UWB base stations to detect unmanned vehicles with on-board UWB tags in real time, wherein the heading angle of the vehicle, that is, the direction of movement, can be calculated in real time based on two UWB base stations, and then two reference UWB base stations in the array are selected to calculate the position of the vehicle based on the heading angle, ensuring that the error of the selected UWB base station in positioning the vehicle is minimized, solving the problem of unmanned driving of vehicles in wide open areas and dusty roads with unclear surrounding environment features, and ensuring that the vehicle can be unmanned with the greatest accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 This is a flow chart of a UWB-based unmanned vehicle positioning method according to an embodiment of the present invention; Figure 2 A schematic diagram of a square array composed of multiple UWB base stations in a UWB-based unmanned vehicle positioning method according to an embodiment of the present invention; Figure 3 A schematic diagram of selecting a UWB base station in a UWB-based unmanned vehicle positioning method according to an embodiment of the present invention; Figure 4 The present invention is a schematic structural diagram of a UWB-based unmanned vehicle positioning terminal according to an embodiment of the present invention.

[0009] Description of labels: 1. A UWB-based unmanned vehicle positioning terminal; 2. Memory; 3. Processor. DETAILED DESCRIPTION

[0010] In order to explain the technical content, achieved objectives and effects of the present invention in detail, the following is an explanation in conjunction with the implementation modes and the accompanying drawings.

[0011] Please refer to Figures 1 to 3, a UWB-based unmanned vehicle positioning method, comprising the steps of: S1. Determine whether the vehicle enters a preset space, wherein a plurality of UWB base stations are deployed in a square array in the preset space, wherein the distances between the UWB base stations adjacent in the horizontal and vertical directions are equal, and the vehicle carries an on-board UWB tag; S2. When the vehicle enters the preset space, calculating the heading angle of the vehicle in real time; S3. Select two UWB base stations in the square array that are perpendicular to the heading angle or one component of the heading angle and closest to the vehicle according to the heading angle, and use the two UWB base stations to determine the current GPS position information of the vehicle.

[0012] From the above description, it can be seen that the beneficial effect of the present invention is that: by deploying a square UWB base station array in a preset space, and having multiple UWB base stations detect unmanned vehicles with on-board UWB tags in real time, real-time positioning of unmanned vehicles traveling in the preset space can be achieved, wherein the heading angle of the vehicle, that is, the direction of movement, can be calculated in real time based on the two UWB base stations, and then two reference UWB base stations in the array are selected to calculate the position of the vehicle based on the heading angle, ensuring that the error of the selected UWB base station in positioning the vehicle is minimized, solving the problem of unmanned driving of vehicles in areas with unclear surrounding environment features, wide open areas and dusty roads, and ensuring that the vehicle can achieve unmanned driving with the greatest accuracy.

[0013] Furthermore, between step S2 and step S3, the following steps are also included: The smallest square array where the vehicle is currently located in the square array is determined according to the UWB base station that can detect the vehicle-mounted UWB tag.

[0014] From the above description, it can be seen that before selecting a UWB base station according to the heading angle, the minimum square array in which the current vehicle is located is first determined, so that multiple UWB base stations in the array are reduced to four UWB base stations, thereby improving the efficiency of base station selection.

[0015] Furthermore, step S3 is specifically as follows: S31. If the heading angle is [0°, 45°) or (135°, 225°) or (315°, 360°], select the two left and right UWB base stations closest to the current vehicle in the minimum square array; If the heading angle is (45°, 135°) or (225°, 315°), then selecting the upper and lower UWB base stations closest to the current vehicle in the minimum square array; If the heading angle is 45°, 135°, 225° or 315°, any group of the UWB base stations from the left and right or upper and lower UWB base stations closest to the current vehicle in the minimum square array is randomly selected.

[0016] From the above description, it can be seen that according to the heading angle, that is, the direction of movement of the vehicle, when the heading angle is [0°, 45°) or (135°, 225°) or (315°, 360°], that is, the direction of movement of the vehicle in the array may be horizontal or inclined to the horizontal direction, then the base station in the minimum square array can be selected as the upper and lower UWB base stations that are perpendicular to the horizontal vertical or oblique horizontal component, but because there are four UWB base stations in the minimum square array, that is, there are two groups of upper and lower UWB base stations, therefore, according to the distances measured by the four UWB base stations from the vehicle, a group of upper and lower UWB base stations with the smallest distance, that is, the closest distance to the vehicle, can be selected; similarly, when the heading angle is (45°, 135°) or (225°, 315°), that is The direction of movement of the vehicle in the array may be vertical or inclined to the vertical, so the base stations in the smallest square array can be selected as two left and right UWB base stations that are perpendicular to the vertical or oblique vertical components, and a group of two left and right UWB base stations with the closest distance to the vehicle measured by the four UWB base stations respectively; in addition, since the vertical component of the heading angle of 45°, 135°, 225° or 315° is equal to the horizontal component, a group of two upper and lower UWB base stations or two left and right UWB base stations can be randomly selected, and it is only necessary to ensure that the two UWB base stations in this group are closest to the vehicle compared to the other group. That is, during the entire driving process of the vehicle, it can be ensured that the UWB base station selected each time is the base station closest to the vehicle and with the best position, thereby ensuring the accuracy of positioning.

[0017] Furthermore, step S2 is specifically as follows: S21. When the vehicle enters the preset space, obtain the GPS location information of two of the UWB base stations that can measure the vehicle-mounted UWB tag, and obtain the longitude and latitude coordinates (lon01, at0) and (lon1, lat1) of the two UWB base stations: S22, calculating the latitude distance distance_North=R×(lat1-lat0) and the longitude distance distance_East=R×cos(lat0)×(lon1-lon0) of the two UWB base stations; S23. Obtain the current heading angle of the vehicle according to the latitude distance and the longitude distance: bearing=mod(atan2(distance_East, distance_North), 2π); Wherein, R is the straight-line distance between the two UWB base stations.

[0018] From the above description, it can be seen that during the driving process of the vehicle, the real-time heading angle of the vehicle is first determined by the longitude and latitude positions of two UWB base stations in the array, which provides a reference basis for the selection of base stations for subsequent calculation of the vehicle position information. That is, the base station in the array is selected based on the real-time heading angle of the vehicle to ensure the accuracy of vehicle positioning.

[0019] Furthermore, the preset space is an area of ​​5 km×5 km; The square array is a 6×6 array, and the distance between the UWB base stations adjacent in the horizontal and vertical directions is 1 km; Before step S1, the method further includes: Automatically calibrate and obtain the GPS location information of each of the UWB base stations deployed in the square array.

[0020] From the above description, it can be seen that in order to solve the problem of unmanned vehicle positioning in a wide range of 5Km×5Km area, a UWB base station can be arranged at intervals of 1Km in the area, and finally a 6×6 rectangular base station array can be formed to ensure the best ranging effect of the UWB base station. At the same time, after the UWB base station is arranged, the GPS location information of each base station is automatically calibrated and obtained, which is compatible with the GPS unmanned driving algorithm, and provides a basis for the subsequent selection of base stations to calculate the vehicle's location information in real time.

[0021] Please refer to Figure 4 , a UWB-based unmanned vehicle positioning terminal, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the following steps when executing the computer program: S1. Determine whether the vehicle enters a preset space, wherein a plurality of UWB base stations are deployed in a square array in the preset space, wherein the distances between the UWB base stations adjacent in the horizontal and vertical directions are equal, and the vehicle carries an on-board UWB tag; S2. When the vehicle enters the preset space, calculating the heading angle of the vehicle in real time; S3. Select two UWB base stations in the square array that are perpendicular to the heading angle or one component of the heading angle and closest to the vehicle according to the heading angle, and use the two UWB base stations to determine the current GPS position information of the vehicle.

[0022] From the above description, it can be seen that the beneficial effects of the present invention are: based on the same technical concept, in conjunction with the above-mentioned UWB-based unmanned vehicle positioning method, a UWB-based unmanned vehicle positioning terminal is provided, by deploying a square UWB base station array in a preset space, and multiple UWB base stations detect unmanned vehicles with on-board UWB tags in real time, so as to realize real-time positioning of unmanned vehicles traveling in the preset space, wherein the heading angle of the vehicle, that is, the direction of movement, can be calculated in real time according to the two UWB base stations, and then two reference UWB base stations in the array for position calculation for the vehicle are selected according to the heading angle, to ensure that the error of the selected UWB base station for positioning the vehicle is minimized, to solve the problem of unmanned driving of vehicles in areas with unclear surrounding environment features, wide open areas and dusty roads, and to ensure that the vehicle can achieve unmanned driving with the highest accuracy.

[0023] Furthermore, between step S2 and step S3, the following steps are also included: The smallest square array where the vehicle is currently located in the square array is determined according to the UWB base station that can detect the vehicle-mounted UWB tag.

[0024] From the above description, it can be seen that before selecting a UWB base station according to the heading angle, the minimum square array in which the current vehicle is located is first determined, so that multiple UWB base stations in the array are reduced to four UWB base stations, thereby improving the efficiency of base station selection.

[0025] Furthermore, step S3 is specifically as follows: S31. If the heading angle is [0°, 45°) or (135°, 225°) or (315°, 360°], select the two left and right UWB base stations closest to the current vehicle in the minimum square array; If the heading angle is (45°, 135°) or (225°, 315°), then selecting the upper and lower UWB base stations closest to the current vehicle in the minimum square array; If the heading angle is 45°, 135°, 225° or 315°, any group of the UWB base stations from the left and right or upper and lower UWB base stations closest to the current vehicle in the minimum square array is randomly selected.

[0026] From the above description, it can be seen that according to the heading angle, that is, the direction of movement of the vehicle, when the heading angle is [0°, 45°) or (135°, 225°) or (315°, 360°], that is, the direction of movement of the vehicle in the array may be horizontal or inclined to the horizontal direction, then the base station in the minimum square array can be selected as the upper and lower UWB base stations that are perpendicular to the horizontal vertical or oblique horizontal component, but because there are four UWB base stations in the minimum square array, that is, there are two groups of upper and lower UWB base stations, therefore, according to the distances measured by the four UWB base stations from the vehicle, a group of upper and lower UWB base stations with the smallest distance, that is, the closest distance to the vehicle, can be selected; similarly, when the heading angle is (45°, 135°) or (225°, 315°), that is The direction of movement of the vehicle in the array may be vertical or inclined to the vertical, so the base stations in the smallest square array can be selected as two left and right UWB base stations that are perpendicular to the vertical or oblique vertical components, and a group of two left and right UWB base stations with the closest distance to the vehicle measured by the four UWB base stations respectively; in addition, since the vertical component of the heading angle of 45°, 135°, 225° or 315° is equal to the horizontal component, a group of two upper and lower UWB base stations or two left and right UWB base stations can be randomly selected, and it is only necessary to ensure that the two UWB base stations in this group are closest to the vehicle compared to the other group. That is, during the entire driving process of the vehicle, it can be ensured that the UWB base station selected each time is the base station closest to the vehicle and with the best position, thereby ensuring the accuracy of positioning.

[0027] Furthermore, step S2 is specifically as follows: S21. When the vehicle enters the preset space, obtain the GPS location information of two of the UWB base stations that can measure the vehicle-mounted UWB tag, and obtain the longitude and latitude coordinates (lon0, lat0) and (lon1, lat1) of the two UWB base stations: S22, calculating the latitude distance distance_North=R×(lat1-lat0) and the longitude distance distance_East=R×cos(lat0)×(lon1-lon0) of the two UWB base stations; S23. Obtain the current heading angle of the vehicle according to the latitude distance and the longitude distance: bearing=mod(atan2(distance_East, distance_North), 2π); Wherein, R is the straight-line distance between the two UWB base stations.

[0028] From the above description, it can be seen that during the driving process of the vehicle, the real-time heading angle of the vehicle is first determined by the longitude and latitude positions of two UWB base stations in the array, which provides a reference basis for the selection of base stations for subsequent calculation of the vehicle position information. That is, the base station in the array is selected based on the real-time heading angle of the vehicle to ensure the accuracy of vehicle positioning.

[0029] Furthermore, the preset space is an area of ​​5 km×5 km; The square array is a 6×6 array, and the distance between the UWB base stations adjacent in the horizontal and vertical directions is 1 km; Before step S1, the method further includes: Automatically calibrate and obtain the GPS location information of each of the UWB base stations deployed in the square array.

[0030] From the above description, it can be seen that in order to solve the problem of unmanned vehicle positioning in a wide range of 5Km×5Km area, a UWB base station can be arranged at intervals of 1Km in the area, and finally a 6×6 rectangular base station array can be formed to ensure the best ranging effect of the UWB base station. At the same time, after the UWB base station is arranged, the GPS location information of each base station is automatically calibrated and obtained, which is compatible with the GPS unmanned driving algorithm, and provides a basis for the subsequent selection of base stations to calculate the vehicle's location information in real time.

[0031] The present invention provides a UWB-based unmanned vehicle positioning method and terminal, which are suitable for scenarios where the surrounding environment features are not obvious within a range of 5km×5km, unmanned driving environment setting up in open areas, dusty roads, and real-time positioning of unmanned vehicles. The following is a detailed description in conjunction with the embodiments.

[0032] Please refer to Figure 1 , Embodiment 1 of the present invention is: A UWB-based unmanned vehicle positioning method, such as Figure 1 As shown, the steps include: S1. Determine whether the vehicle enters a preset space, where multiple UWB base stations are deployed in a square array, where the distances between adjacent UWB base stations in the horizontal and vertical directions are equal, and the vehicle is equipped with an on-board UWB tag; S2. When the vehicle enters the preset space, the heading angle of the vehicle is calculated in real time; S3. Select two UWB base stations in the square array that are perpendicular to the heading angle or one of the components of the heading angle and closest to the vehicle according to the heading angle, and use the two UWB base stations to determine the GPS position information of the current vehicle.

[0033] Among them, UWB is a new type of unmanned driving technology. Its principle is that in the absence of GPS signals, the simplest model is to install a UWB tag on the unmanned vehicle, install two UWB base stations at the boundary of the unmanned driving range, and measure the distance between the vehicle and the two UWB base stations through real-time communication between the vehicle-mounted UWB expression and the UWB base station. The distance of the vehicle based on the two-dimensional plane of the two UWB base stations is calculated by trigonometric functions. In order to be compatible with the GPS unmanned driving algorithm, the GPS location information of the two UWB base stations can be obtained in advance, so that the GPS location information of the vehicle can be calculated in real time.

[0034] However, the communication distance of UWB is generally 500~1000m. Although it can reach 1.5km by modifying the antenna gain, it still cannot meet the requirements of unmanned driving of vehicles within a wide range of 5km×5km. Therefore, in this embodiment, a square UWB base station array is deployed in a preset space, and multiple UWB base stations detect unmanned vehicles with on-board UWB tags in real time. Vehicles with on-board UWB tags are detected by multiple base stations in the square array. When a UWB base station detects the UWB tag, it can be determined that a vehicle has entered the array. At the same time, the real-time positioning of the unmanned vehicle traveling in the preset space can also be performed, wherein the heading angle of the vehicle, that is, the direction of movement, can be calculated in real time according to the two UWB base stations, and then two reference UWB base stations in the array for calculating the position of the vehicle can be selected according to the heading angle to ensure that the error of the selected UWB base station in positioning the vehicle is minimized, thereby solving the problem of unmanned driving of vehicles in wide open areas and dusty roads with unclear surrounding environment features, and ensuring that the vehicle can achieve unmanned driving with the highest accuracy.

[0035] Please refer to Figure 2 and Figure 3 , Embodiment 2 of the present invention is: A method for positioning an unmanned vehicle based on UWB, based on the above embodiment 1, in this embodiment, the preset space is an area of ​​5Km×5Km, such as Figure 2 As shown, the square array is a 6×6 array, and the distance between adjacent UWB base stations in the horizontal and vertical directions is 1 km.

[0036] That is, in order to solve the problem of unmanned vehicle positioning in a wide range of 5Km×5Km area, a UWB base station can be deployed every 1Km in the area, eventually forming a 6×6 rectangular base station array, with a total of 36 UWB base stations, to ensure the best ranging effect of the UWB base station.

[0037] In this embodiment, before step S1, the following steps are also included: Automatically calibrate and obtain the GPS location information of each UWB base station deployed in the square array.

[0038] That is, after the UWB base station is deployed, the GPS location information of each base station is automatically calibrated and obtained, which is compatible with the GPS unmanned driving algorithm, providing a basis for the subsequent selection of base stations to calculate the vehicle's location information in real time.

[0039] Wherein, step S2 is specifically as follows: S21. When the vehicle enters the preset space, the GPS location information of two UWB base stations that can measure the vehicle-mounted UWB tag is obtained, and the longitude and latitude coordinates (lon0, lat0) and (lon1, lat1) of the two UWB base stations are obtained: In this embodiment, after the vehicle enters the square array, it can randomly select two UWB base stations from the UWB base stations in the square array that can detect the vehicle-mounted UWB tags, and then obtain their pre-calibrated GPS position information, i.e., longitude and latitude coordinates, or select two UWB base stations closest to the current measurement distance from the UWB base stations that can detect the vehicle-mounted UWB tags, and obtain their longitude and latitude coordinates.

[0040] S22. Calculate the latitude distance distance_North=R×(lat1-lat0) and the longitude distance distance_East=R×cos(lat0)×(lon1-lon0) of the two UWB base stations.

[0041] Then, the heading angle is calculated according to the inverse tangent formula of the trigonometric function, namely: S23. Obtain the current heading angle of the vehicle according to the latitude distance and the longitude distance: bearing=mod(atan2(distance_East,distance_North),2π); Here, R is the straight-line distance between two UWB base stations. For the convenience of calculation, when selecting two UWB base stations in step S21, two adjacent UWB base stations can be selected, and then R is 1.

[0042] That is, in this embodiment, the real-time heading angle of the vehicle is first determined by the longitude and latitude positions of two UWB base stations in the array during the driving process of the vehicle, providing a reference basis for the selection of base stations for subsequent calculation of the vehicle position information, that is, the base stations in the array are selected based on the real-time heading angle of the vehicle to ensure the accuracy of vehicle positioning.

[0043] Among them, between step S2 and S3 also includes: The smallest square array in which the current vehicle is located is determined based on the UWB base station that can detect the vehicle-mounted UWB tag.

[0044] That is, before selecting a UWB base station according to the heading angle, the minimum square array in which the current vehicle is located is determined first, thereby reducing the multiple UWB base stations in the array to four UWB base stations, improving the efficiency of base station selection, such as Figure 2 In the square array shown, a square array consisting of four UWB base stations adjacent in both horizontal and vertical directions is a minimum square array.

[0045] Wherein, step S3 is specifically as follows: S31. If the heading angle is [0°, 45°) or (135°, 225°) or (315°, 360°], select the two left and right UWB base stations closest to the current vehicle in the minimum square array; That is, the direction of movement of the vehicle in the array may be horizontal or inclined to the horizontal direction, then the base station in the minimum square array can be selected as the upper and lower UWB base stations that are perpendicular to the horizontal component or the oblique horizontal component. However, since there are four UWB base stations in the minimum square array, that is, there are two groups of upper and lower UWB base stations, therefore, according to the distances to the vehicle measured by the four UWB base stations respectively, a group of upper and lower UWB base stations with the smallest distance, that is, the closest distance to the vehicle can be selected. Figure 3 When the moving direction is A, two UWB base stations 1 and 7 can be selected. When the vehicle continues to move in the moving direction A to the intersection of the minimum square array, it can switch to two UWB base stations 2 and 8.

[0046] If the heading angle is (45°, 135°) or (225°, 315°), select the upper and lower UWB base stations closest to the current vehicle in the minimum square array; That is, similar to the above, when the heading angle is (45°, 135°) or (225°, 315°), that is, the direction of movement of the vehicle in the array may be vertical or inclined to the vertical, then the base stations in the minimum square array can be selected as the left and right UWB base stations that are perpendicular to the vertical or inclined vertical component, and according to the left and right UWB base stations with the closest distance to the vehicle measured by the four UWB base stations, refer to Figure 3 When the moving direction is B, two UWB base stations 1 and 2 can be selected. When the vehicle continues to move in the moving direction B to the intersection of the minimum square array, it can switch to two UWB base stations 7 and 8.

[0047] If the heading angle is 45°, 135°, 225° or 315°, any group of UWB base stations from the left or right or upper and lower UWB base stations closest to the current vehicle in the minimum square array is randomly selected; That is, since the vertical component of a heading angle of 45°, 135°, 225° or 315° is equal to the lateral component, a group of two upper and lower UWB base stations or two left and right UWB base stations can be randomly selected, and it is only necessary to ensure that the two UWB base stations in this group are closest to the vehicle compared to the other group.

[0048] That is, in this embodiment, the heading angle is divided and the UWB base station is selected according to the classification of the heading angle. During the entire driving process of the vehicle, it can be ensured that the UWB base station selected each time is the base station closest to the vehicle and has the best position, thereby ensuring the accuracy of positioning.

[0049] Please refer to Figure 3 , Embodiment 3 of the present invention is: A UWB-based unmanned vehicle positioning terminal 1 includes a memory 2, a processor 3, and a computer program stored in the memory 2 and executable on the processor 3. In this embodiment, the processor 3 implements the steps of any one of the above-mentioned embodiments 1 to 2 when executing the computer program.

[0050] In summary, the present invention provides a UWB-based unmanned vehicle positioning method and terminal, which realizes real-time positioning of unmanned vehicles traveling in the preset space by deploying a square UWB base station array in a preset space, and having multiple UWB base stations detect unmanned vehicles with on-board UWB tags in real time, wherein the heading angle of the vehicle, that is, the direction of movement, can be calculated in real time according to two UWB base stations, and then the minimum square array in which the current vehicle is located in the square array can be determined according to the UWB base station that can measure the on-board UWB tag, and then two reference UWB base stations in the minimum square array are selected for position calculation for the vehicle according to the heading angle, to ensure that the error of the selected UWB base station in the vehicle positioning calculation is minimized, solve the problem of unmanned driving of vehicles in areas with unclear surrounding environment features, wide open areas and dusty roads, and ensure that the vehicle can achieve unmanned driving with the highest accuracy.

[0051] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent transformations made using the contents of the present invention's specification and drawings, or directly or indirectly applied in related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A UWB-based unmanned vehicle positioning method, characterized in that: Includes steps: S1. Determine whether the vehicle enters a preset space, wherein a plurality of UWB base stations are deployed in a square array in the preset space, wherein the distances between the UWB base stations adjacent in the horizontal and vertical directions are equal, and the vehicle carries an on-board UWB tag; S2. When the vehicle enters the preset space, calculating the heading angle of the vehicle in real time; S3. Select two UWB base stations in the square array that are perpendicular to the heading angle or one of the components of the heading angle and closest to the vehicle according to the heading angle, and use the two UWB base stations to determine the current GPS position information of the vehicle.

2. The UWB-based unmanned vehicle positioning method according to claim 1, characterized in that: The steps between step S2 and step S3 also include: The smallest square array where the vehicle is currently located in the square array is determined according to the UWB base station that can detect the vehicle-mounted UWB tag.

3. The UWB-based unmanned vehicle positioning method according to claim 2, characterized in that: Step S3 is specifically as follows: S31. If the heading angle is [0°, 45°) or (135°, 225°) or (315°, 360°], select the two left and right UWB base stations closest to the current vehicle in the minimum square array; If the heading angle is (45°, 135°) or (225°, 315°), then selecting the upper and lower UWB base stations closest to the current vehicle in the minimum square array; If the heading angle is 45°, 135°, 225° or 315°, any group of the UWB base stations from the left and right or upper and lower UWB base stations closest to the current vehicle in the minimum square array is randomly selected.

4. The UWB-based unmanned vehicle positioning method according to claim 1, characterized in that: Step S2 is specifically as follows: S21. When the vehicle enters the preset space, obtain the GPS location information of two of the UWB base stations that can measure the vehicle-mounted UWB tag, and obtain the longitude and latitude coordinates (lon0, lat0) and (lon1, lat1) of the two UWB base stations: S22, calculating the latitude distance distance_North=R×(lat1-lat0) and the longitude distance distance_East=R×cos(lat0)×(lon1-lon0) of the two UWB base stations; S23. Obtain the current heading angle of the vehicle according to the latitude distance and the longitude distance: bearing=mod(atan2(distance_East, distance_North), 2π); Wherein, R is the straight-line distance between the two UWB base stations.

5. The UWB-based unmanned vehicle positioning method according to claim 1, characterized in that: The preset space is an area of ​​5 km×5 km; The square array is a 6×6 array, and the distance between the UWB base stations adjacent in the horizontal and vertical directions is 1 km; Before step S1, the method further includes: Automatically calibrate and obtain the GPS location information of each of the UWB base stations deployed in the square array.

6. A UWB-based unmanned vehicle positioning terminal, characterized in that: The invention comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor implements the following steps when executing the computer program: S1. Determine whether the vehicle enters a preset space, wherein a plurality of UWB base stations are deployed in a square array in the preset space, wherein the distances between the UWB base stations adjacent in the horizontal and vertical directions are equal, and the vehicle carries an on-board UWB tag; S2. When the vehicle enters the preset space, calculating the heading angle of the vehicle in real time; S3. Select two UWB base stations in the square array that are perpendicular to the heading angle or one of the components of the heading angle and closest to the vehicle according to the heading angle, and use the two UWB base stations to determine the current GPS position information of the vehicle.

7. The UWB-based unmanned vehicle positioning terminal according to claim 6, characterized in that: The steps between step S2 and step S3 also include: The smallest square array where the vehicle is currently located in the square array is determined according to the UWB base station that can detect the vehicle-mounted UWB tag.

8. The UWB-based unmanned vehicle positioning terminal according to claim 7, characterized in that: Step S3 is specifically as follows: S31. If the heading angle is [0°, 45°) or (135°, 225°) or (315°, 360°], select the two left and right UWB base stations closest to the current vehicle in the minimum square array; If the heading angle is (45°, 135°) or (225°, 315°), then selecting the upper and lower UWB base stations closest to the current vehicle in the minimum square array; If the heading angle is 45°, 135°, 225° or 315°, any group of the UWB base stations from the left and right or upper and lower UWB base stations closest to the current vehicle in the minimum square array is randomly selected.

9. The UWB-based unmanned vehicle positioning terminal according to claim 6, characterized in that: Step S2 is specifically as follows: S21. When the vehicle enters the preset space, obtain the GPS location information of two of the UWB base stations that can measure the vehicle-mounted UWB tag, and obtain the longitude and latitude coordinates (lon0, lat0) and (lon1, lat1) of the two UWB base stations: S22, calculating the latitude distance distance_North=R×(lat1-lat0) and the longitude distance distance_East=R×cos(lat0)×(lon1-lon0) of the two UWB base stations; S23. Obtain the current heading angle of the vehicle according to the latitude distance and the longitude distance: bearing=mod(atan2(distance_East, distance_North), 2π); Wherein, R is the straight-line distance between the two UWB base stations.

10. The UWB-based unmanned vehicle positioning terminal according to claim 6, characterized in that: The preset space is an area of ​​5 km×5 km; The square array is a 6×6 array, and the distance between the UWB base stations adjacent in the horizontal and vertical directions is 1 km; Before step S1, the method further includes: Automatically calibrate and obtain the GPS location information of each of the UWB base stations deployed in the square array.

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