A positioning method of a robot and a robot

Abstract

The present disclosure relates to a positioning method of a robot and the robot. The robot is provided with a satellite positioning sensor and a radar sensor. The satellite positioning sensor is used to obtain a satellite positioning position of the robot at a position detection point. The radar sensor is used to obtain a radar positioning position of the position detection point. The radar positioning position is used to correct the satellite positioning position. The satellite positioning sensor is low in cost, and the positioning precision is high, which meets the positioning requirement of the robot.

Description

Technical Field

[0001] This disclosure relates to the field of automatic control technology, and in particular to a robot positioning method and a robot. Background Technology

[0002] Robots, including automatic lawnmowers, automatic snowplows, and automatic sprinklers, can travel along pre-set paths or move freely without human intervention to perform functions such as mowing, snow removal, and watering. During operation, the robot's position needs to be determined to prevent it from entering unauthorized areas. Related technologies use satellite positioning for robot location; however, satellite positioning is affected by weather, clouds, buildings, and obstructions. Low-cost satellite positioning has low accuracy, while high-precision differential satellite positioning is expensive. Furthermore, satellite positioning has a low frequency, making low-cost satellite positioning insufficient for meeting the positioning needs of robots. Summary of the Invention

[0003] To overcome the problems existing in related technologies and improve the accuracy of satellite positioning while reducing the cost of satellite positioning, this disclosure provides a method, apparatus, and automatic walking device equipped with the apparatus.

[0004] According to a first aspect of the present disclosure, a robot localization method is provided, wherein the robot is equipped with a satellite positioning sensor and a radar sensor, including:

[0005] The satellite positioning sensor is used to obtain the robot's satellite positioning position at the position detection point;

[0006] The radar sensor is used to obtain the radar positioning position of the position detection point;

[0007] The satellite positioning position is corrected using the radar positioning position.

[0008] In one possible implementation, obtaining the radar positioning location of the position detection point using the radar sensor includes:

[0009] The distance between the location detection point and multiple radar reflectors is obtained using the radar sensor.

[0010] The radar positioning location of the location detection point is determined based on the distance.

[0011] In one possible implementation, the plurality of radar reflectors includes at least three radar reflectors.

[0012] In one possible implementation, obtaining the radar positioning location of the position detection point using the radar sensor includes:

[0013] The distance between the position detection point and the radar reflector, and the angle between the radar reflector and the robot's direction of travel are obtained using the radar sensor.

[0014] The radar positioning position of the location detection point is determined based on the distance, the included angle, and the heading angle of the robot at the location detection point.

[0015] In one possible implementation, the robot is further equipped with an inertial sensor, and the heading angle of the robot at the position detection point is set to be obtained in the following manner:

[0016] Based on the robot's pose data acquired by the inertial sensor, the heading angle of the robot at the position detection point is determined.

[0017] In one possible implementation, obtaining the angle between the radar reflector and the robot's travel direction using the radar sensor includes:

[0018] The radar sensor is used to obtain the moment when the robot sends a signal to the radar reflector at the location detection point.

[0019] Based on the correlation between the time when the radar sensor sends a signal and the angle of signal transmission, the angle between the radar reflector and the robot's direction of travel is determined.

[0020] In one possible implementation, obtaining the radar positioning location of the position detection point using the radar sensor includes:

[0021] The distances between multiple consecutive detection points and radar-reflecting objects are obtained respectively;

[0022] Determine the angle between the radar-reflecting object and the robot's direction of travel at the plurality of consecutive detection points;

[0023] The relative positions between adjacent position detection points are determined based on the distances between the multiple consecutive position detection points and the radar-reflecting object, as well as the angle between the radar-reflecting object and the robot's direction of travel.

[0024] In one possible implementation, determining the relative positions between adjacent position detection points based on the distances between the plurality of consecutive position detection points and the radar-reflecting object, and the angle between the radar-reflecting object and the robot's travel direction, includes:

[0025] Based on the distances between the multiple consecutive position detection points and the radar-reflecting object, and the angle between the radar-reflecting object and the robot's direction of travel, the relative distances between adjacent position detection points are determined.

[0026] The relative positions of adjacent detection points are determined based on the relative distance between them and the direction of travel of the robot.

[0027] In one possible implementation, correcting the satellite positioning position using the radar positioning position includes:

[0028] Replace the satellite positioning location at the location detection point with the radar positioning location.

[0029] In one possible implementation, correcting the satellite positioning position using the radar positioning position includes:

[0030] Using the satellite positioning location as the first location detection point, the position of the location detection point adjacent to the first location detection point is determined based on the relative position of the location detection point adjacent to the first location detection point.

[0031] In one possible implementation, the radar-reflecting object is positioned on the boundary of the robot's working area.

[0032] In one possible implementation, the radar-reflecting object includes obstacles within the robot's working area.

[0033] According to a second aspect of this disclosure, a robot is provided, comprising:

[0034] The robot body includes a movement module, an energy module, a control module, and a function module. The movement module includes a wheel set and a drive motor to drive the wheel set. The energy module includes a battery pack for powering the robot's movement. The function module is used to realize the robot's purpose. The control module is electrically connected to the movement module, energy module, and function module to control the robot's movement and operation.

[0035] Satellite positioning sensors and radar sensors;

[0036] A processor configured to perform the methods described in any embodiment of this disclosure.

[0037] In one possible implementation, the robot also includes inertial sensors.

[0038] In one possible implementation, the functional module includes at least one of the following:

[0039] A cutting function component, including a cutting blade and a motor that drives the cutting blade to operate;

[0040] Snow removal function components include a snow removal brush and a motor that drives the snow removal brush to operate;

[0041] The water spraying function components include a water tank, a water gun, and a motor that drives the water gun to operate.

[0042] The technical solutions provided by the embodiments of this disclosure can include the following beneficial effects: By utilizing a radar sensor to obtain the radar positioning position of the position detection point and performing position correction on the satellite positioning position at the position detection point, the beneficial effect achieved is that high positioning accuracy can be obtained even with low-cost satellite positioning, meeting the positioning requirements of the robot. Furthermore, considering the potential inconsistency between the positioning frequency and the transmission frequency, this disclosure corrects for them, ensuring the uniformity of the position detection points and guaranteeing the accuracy of the position correction.

[0043] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure. Attached Figure Description

[0044] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure.

[0045] Figure 1(a) is an application scenario diagram of a robot localization method according to an exemplary embodiment.

[0046] Figure 1(b) is an application scenario diagram of a robot localization method according to an exemplary embodiment.

[0047] Figure 2(a) is an application scenario diagram of a robot localization method according to an exemplary embodiment.

[0048] Figure 2(b) is an application scenario diagram of a robot localization method according to an exemplary embodiment.

[0049] Figure 3(a) is an application scenario diagram of a robot localization method according to an exemplary embodiment.

[0050] Figure 3(b) is an application scenario diagram of a robot localization method according to an exemplary embodiment.

[0051] Figure 4 This is a flowchart illustrating a robot localization method according to an exemplary embodiment.

[0052] Figure 5This is a schematic diagram of the structure of a robot according to an exemplary embodiment. Detailed Implementation

[0053] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numerals in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this disclosure. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this disclosure as detailed in the appended claims.

[0054] To facilitate understanding of the technical solutions provided by the embodiments of this disclosure by those skilled in the art, the technical environment for implementing the technical solutions will be described below.

[0055] Satellite positioning technologies, such as the commonly used GPS global positioning system, are frequently applied in areas such as robot positioning and mobile phone positioning. Low-cost GPS positioning technology suffers from positioning errors due to cloud cover and weather conditions, resulting in an accuracy of 10-20 meters. For robots with cleaning functions, this can lead to significant deviations in their movement, affecting operational efficiency. High-cost GPS technologies, such as differential GPS, utilize ground-based base stations. The precise location of these base stations is known. When the distance between the base station's GPS receiver and the robot's GPS receiver is close (<30km), their GPS signals are considered to travel through the same atmospheric region, and their signal errors are essentially the same. By using the precise location of the base station and the signal propagation time, the signal propagation error caused by weather can be deduced. This error can then be used to correct the vehicle's GPS signal, reducing the impact of clouds and weather on signal transmission. Differential GPS technology can achieve meter-level positioning accuracy, but its high cost limits its application. Furthermore, satellite positioning has a low positioning frequency, typically only 10Hz, meaning it takes 100ms to get a position. When the robot is moving at a high speed, the distance between two positioning results may differ significantly.

[0056] Based on practical technical needs similar to those described above, this disclosure provides a robot positioning method that can achieve high-precision positioning using low-cost satellite positioning sensors.

[0057] Figures 1(a) and 1(b) are application scenario diagrams illustrating a robot localization method according to an exemplary embodiment. Referring to Figure 1(a), a robot 100 is equipped with a satellite positioning sensor and a radar sensor 106. The robot 100 moves within a working area 105, which contains a first radar reflector 107, a second radar reflector 103, and a third radar reflector 108. The robot 100 continuously uses the satellite positioning sensor to determine its satellite positioning position and simultaneously uses the radar sensor 106 to scan. When 103 is within the scanning range 101 of the radar sensor 106, the distance between the robot 100's current position detection point and the radar reflector can be determined using the radar sensor data. Referring to Figure 1(b), assuming the robot 100 is located at position detection point A, the distance R1 from position detection point A to the first radar reflector 107, the distance R2 to the second radar reflector 103, and the distance R3 to the third radar reflector 108 can be determined using the received radar sensor data. With the first radar reflector 107 as the center and R1 as the radius, we obtain circle one; with the second radar reflector 103 as the center and R2 as the radius, we obtain circle two; and with the third radar reflector 108 as the center and R3 as the radius, we obtain circle three. Assuming the coordinates of the first radar reflector 107, the second radar reflector 103, and the third radar reflector 108 are known, the coordinates of the intersection point of the two circles can be calculated using the equations for circles one and two. By substituting these two intersection point coordinates into the equation for circle three, the intersection point that satisfies the equation for circle three is determined as point A.

[0058] Figures 2(a) and 2(b) are application scenario diagrams illustrating a robot localization method according to an exemplary embodiment. Referring to Figure 2(a), a robot 100 is equipped with a satellite positioning sensor and a radar sensor 106. The robot 100 travels within a working area 105, where a second radar reflector 103 is provided. By receiving radar sensor data, the distance between the second radar reflector 103 and the current position detection point of the robot 100 can be determined, as well as the angle between the second radar reflector 103 and the robot 100's traveling direction. Referring to Figure 2(b), the current position detection point of robot 100 is at point A. The heading angle a of robot 100 can be obtained, as well as the angle b between the direction AC of the second radar reflector 103 and the direction AF. By using ab = c, the angle c between the direction AC of the second radar reflector 103 and the due north direction can be determined. Since the distance AC can be determined by sensor data, the distance CH from the position C of the second radar reflector 103 to the due north direction AG can be determined, and the distance AH can also be determined. If the position of point C is known, the coordinate position of the position detection point A can be determined.

[0059] Figures 3(a) and 3(b) are application scenario diagrams illustrating a robot positioning method according to an exemplary embodiment. Referring to Figure 1(a), a robot 100 is equipped with a satellite positioning sensor and a radar sensor 106. The robot 100 moves within a work area 105, which contains a second radar reflector 103 and a fourth radar reflector 104. The robot 100 continuously uses the satellite positioning sensor to determine its satellite positioning position and simultaneously uses the radar sensor 106 to scan. When the radar reflector 103 is within the scanning range 101 of the radar sensor 106, the distance from the robot 100's position detection point to the radar reflector 103 can be determined using radar sensor data. Referring to Figure 1(b), the position detection point... The distance from point A to radar reflector 103 is l1, and the distance from point B to radar reflector 103 is l2. When the lidar reflects back along l1, the angle between the lidar and the direction of travel (the direction indicated by the arrow, i.e., the direction of the line connecting AB) at the corresponding moment the lidar was emitted can be determined. This angle is the angle between l1 and the direction of travel. Similarly, the angle between l2 and the direction of travel can be determined. Based on the length values ​​of l1 and l2, the radar measurement distances of point A and point B can be obtained. Based on this distance and the direction of travel, the relative position of point B and point A can be determined, and the satellite positioning position of point B can be corrected.

[0060] The following is in conjunction with the appendix Figure 4 The robot positioning method described in this disclosure is explained in detail. Figure 4 This is a flowchart illustrating one embodiment of a robot localization method provided in this disclosure. While this disclosure provides method operation steps as shown in the following embodiments or figures, more or fewer operation steps may be included in the method based on conventional or non-inventive effort. For steps that do not logically have a necessary causal relationship, the execution order of these steps is not limited to the execution order provided in the embodiments of this disclosure. These include:

[0061] Step S401: Use the satellite positioning sensor to obtain the satellite positioning position of the robot at the position detection point.

[0062] In this embodiment, the satellite positioning sensor can receive signals from a combined Global Navigation Satellite System (GNSS), as well as signals from independent navigation satellite systems, such as the US GPS, Russia's GLONASS, Europe's Galileo, and China's BeiDou Navigation Satellite System. It can also receive signals from related augmentation systems, such as the US WAAS (Wide Area Augmentation System), Europe's EGNOS (European Geostationary Navigation Overlay System), and Japan's MSAS (Multifunctional Transport Satellite Augmentation System). Furthermore, it can receive signals from other satellite navigation systems under construction or planned for future construction. The multiple continuous position detection points can include position points along any travel path within the work area or position points on the boundaries of the work area. When a position detection point is located within the work area, it indicates that the robot may be performing a navigation task; when a position detection point is located on the boundaries of the work area, it indicates that the robot may be performing a mapping task. The work area includes, for example, the robot's mowing area, garden path, sprinkler path, etc. The boundary of the work area includes a virtual boundary used to define the robot's working range, such as the boundary between the robot's mowing area and the non-mowing area, the two sides of the garden path, the two sides of the sprinkler path, or the boundary of certain facilities within the work area, such as the boundaries of the fountain, the boundaries of the trees, etc.

[0063] Step S402: Use the radar sensor to obtain the radar positioning position of the position detection point.

[0064] In this embodiment, the radar sensor includes a single-line radar sensor and a multi-line radar sensor. To reduce costs, this solution can also be implemented using a single-line radar sensor. Specifically, based on the working principle of the radar sensor: the transmitter of the lidar rotates uniformly inside the lidar, emitting a laser beam once for each small rotation angle. After the laser beam encounters an object, it returns to the laser receiver after diffuse reflection. The radar sensor calculates the distance between the transmitter and the object by multiplying the time interval between the transmitted and received signals by the speed of light and then dividing by 2. Therefore, in one example, the position of the location detection point can be determined using the lidar's emission angle and the distance between the lidar and the radar reflector, thus obtaining the radar positioning position of the location detection point. In another example, the radar positioning position of the location detection point can be determined using the lidar's emission angle, the distance between the lidar and the object, and the robot's heading angle at the location detection point. In another example, multiple single-line radars are used to pre-scan the surrounding environment and create a map of the surrounding environment using lidar. During operation, the lidar scans the surrounding environment to obtain the point cloud features of radar reflectors. The point cloud features are then matched with the pre-created map to determine the robot's position on the map. It should be noted that the method of obtaining the radar positioning position of the position detection point is not limited to the above example. Those skilled in the art may make other changes based on the essence of the technology in this application, but as long as the function and effect achieved are the same as or similar to this application, they should all be covered within the scope of protection of this application.

[0065] Step S403: Correct the satellite positioning position using the radar positioning position.

[0066] In this embodiment, the satellite positioning location includes the location of the position detection point determined by the aforementioned satellite sensor. Considering that the positioning frequency of the satellite signal (the reciprocal of the interval between receiving satellite signals) and the transmission frequency of the lidar (the reciprocal of the interval between emitting laser signals) may differ, the positioning frequency and transmission frequency can be calibrated to ensure the uniformity of the position detection point. In one example, correcting the satellite positioning location using the radar positioning location includes replacing the position detection point except for the first satellite positioning location with the radar positioning location. In another example, replaceable position detection points can be set according to the strength of the satellite signal on the satellite signal receiver. For example, when a strong satellite signal is detected, the satellite positioning signal location is used as the position detection point; when a weak satellite signal is detected, the radar positioning location is used as the position detection point. It should be noted that the method of correcting the satellite positioning location using the radar positioning location is not limited to the above examples. Those skilled in the art may make other modifications based on the essence of this application, but as long as the function and effect achieved are the same as or similar to this application, they should be covered within the scope of protection of this application.

[0067] This disclosure utilizes a radar sensor to acquire the radar positioning position of the position detection point and then corrects the satellite positioning position at that point. The beneficial effect is that high positioning accuracy can be achieved even with low-cost satellite positioning, meeting the positioning requirements of the robot. Furthermore, this disclosure considers the potential inconsistency between the positioning frequency and the transmission frequency, and therefore corrects for them, ensuring the uniformity of the position detection point and the accuracy of the position correction.

[0068] In one possible implementation, step S402, which uses the radar sensor to obtain the radar positioning location of the position detection point, includes:

[0069] Step S404: Use the radar sensor to obtain the distance between the position detection point and multiple radar reflectors;

[0070] Step S405: Determine the radar positioning position of the position detection point based on the distance.

[0071] In this embodiment, the radar reflector may include a pre-set object, and the type of radar reflector may include obstacles, large trees, rocks, landscapes, etc. The spatial location of the radar reflector may be known. The scanning angle range of the radar sensor may include 360 ​​degrees or other preset angles, and multiple radar reflectors scanned at the same location detection point may be selected as the basis for calculating the location detection point. According to the method described in any of the above embodiments for determining the distance from the location detection point to the radar reflector using radar sensor data, the distance between the location detection point and multiple radar reflectors is determined.

[0072] Based on the distance, the radar location of the position detection point can be determined using a triangulation algorithm or a maximum likelihood positioning method. The triangulation algorithm involves drawing circles with each of the multiple radar reflectors as its center and the distance from the position detection point to the radar reflector as its radius; the intersection of these three circles is the location of the position detection point.

[0073] The embodiments disclosed herein determine the radar positioning position of the position detection point by pre-setting multiple radar reflectors and measuring the distance from the position detection point to the multiple radar reflectors. This has the advantages of low computational complexity, ease of implementation, and reduced cost.

[0074] In one possible implementation, the plurality of radar reflectors includes at least three radar reflectors. In this embodiment of the disclosure, when the number of radar reflectors is three, the radar positioning location of the position detection point can be determined; when the number of radar reflectors is greater than three, a more accurate radar positioning location can be obtained through multiple calculations.

[0075] In one possible implementation, step S402, which uses the radar sensor to obtain the radar positioning location of the position detection point, includes:

[0076] Step S406: Use the radar sensor to obtain the distance between the position detection point and the radar reflector and the angle between the radar reflector and the robot's driving direction;

[0077] Step S407: Determine the radar positioning position of the position detection point based on the distance, the included angle, and the heading angle of the robot at the position detection point.

[0078] In this embodiment of the disclosure, the number of radar reflectors may include one or more. If a radar reflector is detected within the scanning range of the radar sensor, the distance can be determined using the method described in any of the above embodiments for determining the distance from the location detection point to the radar reflector. In one example, the angle between the radar reflector and the robot's travel direction can be determined by the electromagnetic wave signal reflected by the radar reflector received by the radar sensor, or by the rotation angle of the radar sensor.

[0079] In this embodiment of the disclosure, the heading angle of the position detection point includes the angle between the robot's walking direction and the due north (east, south, west) direction. The angle between the radar reflector and the due north (east, south, west) direction can be determined based on the angle between the radar reflector and the robot's walking direction, and the robot's heading angle at the position detection point. The abscissa and ordinate of the position detection point relative to the radar reflector can then be determined using the distance from the position detection point to the radar reflector. When the position of the radar reflector is known, the position of the position detection point can be determined.

[0080] This disclosure allows the robot's position at a location detection point to be determined using a radar sensor, a radar reflector at a known location, and the robot's heading angle at the location detection point. This method has the advantages of low computational complexity, ease of implementation, and reduced costs.

[0081] In one possible implementation, the robot is further equipped with an inertial sensor, and the heading angle of the robot at the position detection point is set to be obtained in the following manner:

[0082] Step S408: Determine the heading angle of the robot at the position detection point based on the robot's pose data acquired by the inertial sensor.

[0083] In this embodiment of the disclosure, a strapdown inertial navigation system can be installed on the robot to acquire the robot's position data using inertial sensors, and the heading angle of the robot at the position detection point can be determined by a strapdown algorithm.

[0084] In one possible implementation, step S406, which uses the radar sensor to obtain the angle between the radar reflector and the robot's travel direction, includes:

[0085] Step S410: Use the radar sensor to obtain the time when the robot sends a signal to the radar reflector at the position detection point;

[0086] Step S411: Determine the angle between the radar reflector and the robot's driving direction based on the correlation between the time the radar sensor sends the signal and the angle of signal transmission.

[0087] In this embodiment, based on the working principle of the radar sensor, the lidar transmitter rotates uniformly inside the lidar, emitting a laser beam for each small rotation angle. The signal transmission angle includes the rotation angle of the lidar transmitter. Therefore, a correlation can be established between the signal transmission time and the signal transmission angle. In one example, this correlation includes setting the initial position of the lidar transmitter to the leftmost end, corresponding to an initial time of 0 seconds. Afterward, each small rotation angle of the lidar transmitter corresponds to one time. When the lidar transmitter scans from the left end to the right end, it scans from the right end to the left end. Thus, the emission angle of the lidar transmitter corresponds to multiple times. The determination of these times can be achieved using a timing device. Therefore, by obtaining the signal transmission time of the lidar transmitter, the signal transmission angle can be determined. When the radar reflector is close to the robot, the signal transmission angle and the signal reception angle are consistent. It can be pre-set that, before installing the lidar sensor, the robot's driving direction is perpendicular to the lidar's emission surface. Therefore, the angle between the radar reflector and the robot's driving direction can be determined.

[0088] In one possible implementation, the positions of other location detection points can be determined as follows: In one example, the same method as in the above embodiments can be used to determine the positions of other location detection points. This allows the machine to operate automatically without setting boundary lines in the work area. In another example, the same method as in the above embodiments can be used to determine the positions of multiple other location detection points. Based on the precise coordinates of the multiple location detection points and the acquired satellite positioning positions of the multiple location detection points, the correlation between the two can be obtained. For example, the correlation can be obtained through a fitting method. For subsequent location detection points, the precise position coordinates can be determined using this correlation. In another example, if the positioning accuracy of the satellite positioning position conforms to a Gaussian distribution, that is, if the satellite positioning position changes with the Gaussian model over time, the precise coordinate positions of other location detection points can be calculated based on the usage time of the satellite positioning sensor and the precise coordinates of the location detection points determined by any of the methods in the above embodiments.

[0089] In one possible implementation, step S402, which utilizes the radar sensor to obtain the radar positioning location of the position detection point, includes:

[0090] Step S412: Obtain the distances between the plurality of consecutive position detection points and the radar-reflecting object;

[0091] Step S413: Determine the angle between the radar-reflecting object and the robot's direction of travel at the plurality of consecutive position detection points;

[0092] Step S414: Based on the distance between the multiple consecutive position detection points and the radar reflective object, and the angle between the radar reflective object and the robot's driving direction, determine the relative position between adjacent position detection points.

[0093] In this embodiment of the disclosure, the distance between the location detection point and the radar reflector can be obtained by emitting a laser beam at the radar reflector using a lidar. After the laser beam encounters the object, it undergoes diffuse reflection and returns to the laser receiver. The distance is then obtained by multiplying the time interval between the transmitted and received signals by the speed of light and dividing by 2 using a radar sensor.

[0094] In this embodiment of the disclosure, the angle between the radar-reflecting object and the robot's direction of travel can, in one example, be obtained by measuring the amplitude or phase response of electromagnetic waves arriving from different directions using a radar signal receiving device. Specifically, this can include amplitude-based direction finding and phase-based direction finding. The amplitude-based direction finding involves determining the angle of arrival of the signal based on the relative amplitude of the received radar signal, including the maximum signal method, the equal signal method, and the comparison signal method. The phase-based direction finding involves determining the angle of arrival of the signal based on the relative phase difference of the received signals. Furthermore, the angle error signal can be demodulated using the phase difference to drive the radar signal receiving device to passively track the radar reflector. In another example, the transmission angle of the radar signal, i.e., the angle between the radar reflector and the robot's direction of travel, can also be determined by utilizing the correlation between the transmission time and the transmission angle of the radar signal.

[0095] In this embodiment, the relative position between adjacent position detection points includes the relative position of the robot's next position detection point compared to its current position detection point, with the interval between the two moments determined by the satellite positioning frequency. In one example, at a certain position detection point, a lidar sends a radar signal to a radar-reflecting object and receives a feedback signal from the object. Using the method described in the above embodiment, the distance from the radar-reflecting object to the position detection point, and the angle between the radar-reflecting object's direction and the travel direction, can be obtained. Similarly, at the next position detection point, the distance between the radar-reflecting object and the next position detection point, as well as the angle between the radar-reflecting object's direction and the travel direction, can also be obtained. Thus, the relative position between the next position detection point and the current position detection point is determined using triangulation. It should be noted that the method of obtaining the relative position between adjacent position detection points is not limited to the examples described above. Those skilled in the art may make other modifications based on the essence of this application, but as long as the achieved function and effect are the same as or similar to this application, they should be covered within the scope of protection of this application.

[0096] In one possible implementation, step S414, determining the relative position between adjacent position detection points based on the distances between the plurality of consecutive position detection points and the radar-reflecting object and the angle between the radar-reflecting object and the robot's travel direction, includes:

[0097] Step S415: Based on the distance between the multiple consecutive position detection points and the radar reflective object, and the angle between the radar reflective object and the robot's driving direction, determine the relative distance between adjacent position detection points.

[0098] Step S416: Determine the relative positions between adjacent detection points based on the relative distance between the adjacent detection points and the robot's travel direction.

[0099] In this embodiment, the distance between the current position detection point and the radar reflector, the angle between the radar reflector and the driving direction at the current moment, and the distance between the next adjacent position detection point and the radar reflector, as well as the angle between the next adjacent radar reflector and the driving direction, can be used to determine the angle between the two reflections of the radar reflector based on the relationship between the exterior and interior angles of a triangle. Using this angle, the distance from the radar reflector to the current position detection point, and the distance to the next adjacent position detection point, the distance from the next adjacent position detection point to the current position detection point can be calculated using the law of cosines. Since the interval between adjacent position detection points is short, the driving direction of the current position detection point can be used as the relative direction between the two detection points, and combined with the distance between the detection points, the relative position between adjacent detection points can be determined. It should be noted that the method for calculating the distance between adjacent position detection points and the method for calculating the relative position based on the distance and driving direction are not limited to the examples described above. Those skilled in the art may make other modifications based on the essence of this application, but as long as the achieved function and effect are the same as or similar to this application, they should be covered within the scope of protection of this application.

[0100] In one possible implementation, step S403 involves correcting the satellite positioning position using the radar positioning position. This includes:

[0101] Step S417: Using the satellite positioning location as the first position detection point, determine the position of the position detection point adjacent to the first position detection point based on the relative position of the position detection point adjacent to the first position detection point and the first position detection point.

[0102] In this embodiment, the satellite positioning location is used as the first position detection point. Based on the radar sensor data described in the previous embodiment, the relative positions of adjacent position detection points and the first position detection point are determined, thereby identifying the adjacent position detection points. The position of these adjacent points may differ from the position of the satellite positioning point at the same time. The position calculated using radar sensor data is taken as the standard and used as the adjacent position detection point. In another example, the position of the position detection point at the next moment can be determined based on the strength of the satellite signal. If the satellite signal is strong, the satellite positioning position can be used; if the satellite signal is weak, the radar positioning position can be used.

[0103] In one possible implementation, step S417, using the satellite positioning location as the first position detection point, determines the position of the position detection points adjacent to the first position detection point based on their relative positions to the first position detection point, including:

[0104] Step S418: Using the satellite positioning location as the first position detection point, determine the position of the position detection point adjacent to the first position detection point based on the relative position of the position detection point adjacent to the first position detection point and the first position detection point.

[0105] Step S419: Using the position detection point adjacent to the first position detection point as the second position detection point, determine a number of position detection points between the first position detection point and the second position detection point.

[0106] In this embodiment, the positions of adjacent position detection points can be determined according to the method of any of the above embodiments, which will not be elaborated here. In this embodiment, several position detection points are inserted between the first and second position detection points, taking into account the positioning frequencies of the first and second position detection points. These positioning frequencies include the positioning frequency of satellite positioning sensors and the positioning frequency of radar sensors. If the positioning frequency is relatively low, it indicates a longer time interval between the position detection points. If the robot's travel speed is high, there will be a longer distance between the first and second position detection points. Therefore, in one example, more refined positioning of the interval distance is required. The positioning method may include: ultrasonic positioning technology, Bluetooth positioning technology, infrared positioning technology, radio frequency positioning technology, ultra-wideband positioning technology, wireless local area network, optical tracking positioning technology, as well as image analysis, computer vision, etc.

[0107] In one possible implementation, step S419 involves determining a plurality of position detection points between the first and second position detection points, using position detection points adjacent to the first position detection point as second position detection points. This includes:

[0108] Step S420: Obtain sensor data between the first position detection point and the second position detection point;

[0109] Step S421: Based on the sensor data between the first position detection point and the second position detection point, determine a plurality of position detection points between the first position detection point and the second position detection point.

[0110] In this embodiment of the disclosure, the sensor may include: an inertial navigation sensor, such as a gyroscope and an accelerometer, wherein the gyroscope is used to calculate the angular velocity value, and the deflection angle relative to the initial direction is calculated by integrating and accumulating the angular velocity value. Where δ is the deflection angle relative to the initial direction at time t, w is the instantaneous angular velocity, and t0 is the initial time. The angle or position parameter can be obtained by one or two integrations of the measured value. In another example, the sensor may further include: a rotating receiver; given three or more beacon positions, the rotating receiver scans the beacon positions to obtain the relative angle between the beacon positions and the location of the rotating receiver; and the position of the measurement point is calculated using triangulation based on the relative angle. It should be noted that the sensor configuration is not limited to the examples above. Those skilled in the art may make other modifications based on the essence of this application, but as long as the function and effect achieved are the same as or similar to this application, they should be covered within the scope of protection of this application.

[0111] In one possible implementation, the robot localization method further includes:

[0112] Step S422: Use the known position detection point as the starting point of the plurality of consecutive position detection points.

[0113] In this embodiment of the disclosure, the known location may include pre-obtained precise location coordinates, which may be obtained through carrier phase differential technology (RTK) combined with GPS. Considering that radar positioning sensors obtain the relative positions between adjacent location detection points when performing location point positioning, using a known location as the starting point is beneficial for the accuracy of subsequent position correction. In one example, when performing path planning, a known location can be set as the starting point. In another example, an object with a specified known location within the work area can be used as the starting point; for example, if the location of a tree is known, the tree can be used as the robot's starting point. Alternatively, the robot's charging station can be used as the starting point.

[0114] In one possible implementation, the radar-reflecting object is positioned on the boundary of the robot's working area.

[0115] In this embodiment, the boundary of the working area is considered: it defines the robot's working range, such as the boundary between the robot's mowing area and the non-mowing area. Therefore, if the robot's positioning is inaccurate, it will cross the boundary of the working area, potentially causing adverse consequences. Thus, it is necessary to ensure the robot's positioning accuracy at the boundary of the mowing area. Therefore, the radar reflector is placed on the boundary of the robot's working area.

[0116] In one possible implementation, the radar-reflecting object includes obstacles within the robot's working area.

[0117] In this embodiment, the radar reflector can be an obstacle within the working area, such as a flowerpot, tree, or landscape structure. To prevent excessively large obstacles from causing differences in edge coordinates, a standard object can be artificially set as the radar reflector. This standard object includes cylindrical or rectangular objects with the same height and width. This embodiment allows for the selection of either an obstacle within the working area or a standard object as the radar reflector, improving the feasibility of the solution.

[0118] The robot with cutting function components in this embodiment may include an automatic lawnmower, a sweeping robot, an automatic snow sweeper, or an automatic sprinkler. Of course, the robot is not limited to automatic lawnmowers, sweeping robots, automatic snow sweepers, or automatic sprinklers, and may also be other devices suitable for unattended operation. This application does not limit the scope of the application.

[0119] In the following specific embodiments, the robot is described in detail using an automatic lawnmower as an example. Figure 5 This is a schematic diagram illustrating the structure of a robot according to an exemplary embodiment. (Reference) Figure 5As shown, the lawnmower body 20 includes a housing 27, a movement module, an energy module, a control module, and a functional module. The movement module includes a wheel set and a drive motor to move the wheel set. Typically, the wheel set includes a drive wheel 211 driven by a walking motor and an auxiliary wheel 212 that supports the housing. It is understood that the movement module may include a track structure. In one example, the walking motor can be directly connected to the drive wheel, with each of the right and left drive wheels connected to a separate walking motor to achieve differential output control steering. In another example, the walking motor can also be driven by a transmission device, i.e., the same motor drives the right and left drive wheels through different transmission devices to achieve differential output control steering. The functional module is used to realize the robot's purpose. In this embodiment, the functional module is the mowing module, including a cutting blade 221, which can be driven by a cutting motor 222. The center of the working module 22 is located on the central axis X of the lawnmower body 20, below the housing, between the auxiliary wheel and the drive wheel, or it can be offset to the left or right side of the housing. The energy module includes a battery pack for powering the robot's movement and movement. The energy module is fixedly or detachably mounted on the housing and may include the battery pack, etc. During operation, the battery pack releases electrical energy to maintain the lawnmower's operation and movement. When not in operation, the battery can be connected to an external power source to replenish power; the automatic lawnmower can also automatically locate a base station to replenish power when it detects insufficient power. The control module is electrically connected to the movement module, energy module, and functional module to control the robot's movement and operation; a satellite positioning sensor and a radar sensor; and a processor configured to execute the method described in any one of the embodiments of this disclosure. The lawnmower body may further include: a satellite positioning sensor and a radar sensor; a processor configured to execute the positioning method described in any embodiment of this disclosure; the processor may exist as a separate positioning device along with the satellite sensor and radar sensor, or it may be integrated with the robot; the positioning device may be detachably or fixedly mounted on the robot; and a communication module for communication between the lawnmower and a client or server.

[0120] In one possible implementation, the functional module includes at least one of the following:

[0121] A cutting function component, including a cutting blade and a motor that drives the cutting blade to operate;

[0122] Snow removal function components include a snow removal brush and a motor that drives the snow removal brush to operate;

[0123] The water spraying function components include a water tank, a water gun, and a motor for operating the water gun.

[0124] In this embodiment, the robot's working system includes a robot, a boundary, and a base station. The robot walks and works within the working area defined by the boundary. The base station can be used to allow the robot to return and replenish its energy when it is low on power. The boundary can include the perimeter of the entire working area, which can be called the outer boundary. It is usually connected end to end, enclosing the working area, and can be electronic or physical. The physical boundary can include the natural physical boundary formed between the working area and the non-working area, such as the natural boundary between grass and non-grass, or the boundary formed by walls, fences, railings, etc. The electronic boundary can be formed by laying lines around the working area and using a virtual boundary signal emitted by a boundary signal generator connected to the wire, such as electromagnetic signals, sound signals, or light signals. There may also be areas in the working area that are unsuitable for the robot to work in, and these areas can form a boundary, such as flower beds, pools, obstacles, etc., which can be called the inner boundary. The part outside the inner boundary is the working area.

[0125] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this disclosure are indicated by the following claims.

[0126] It should be understood that this disclosure is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this disclosure is limited only by the appended claims.

Claims

1. A robot localization method, characterized in that, The robot is equipped with a satellite positioning sensor, a radar sensor, and an inertial sensor. The method includes: The satellite positioning sensor is used to obtain the robot's satellite positioning position at the position detection point; The radar sensor is used to obtain the radar positioning position of the position detection point; In response to a satellite signal level below a threshold, the radar location is used as the current location detection point. Acquire inertial sensor data between a first position detection point and a second position detection point, wherein the first position detection point is the previous position detection point and the second position detection point is the current position detection point; Several other position detection points are provided between the first position detection point and the second position detection point. The positions of the several other position detection points are determined based on the inertial sensor data.

2. The method according to claim 1, characterized in that, The radar sensors include single-line radar sensors and multi-line radar sensors.

3. The method according to claim 1, characterized in that, The positioning frequency of the satellite positioning sensor is the same as the transmission frequency of the radar sensor.

4. The method according to claim 1, characterized in that, The step of obtaining the radar positioning location of the position detection point using the radar sensor includes: The distance between the location detection point and multiple radar reflectors is obtained using the radar sensor. The radar positioning location of the location detection point is determined based on the distance.

5. The method according to claim 4, characterized in that, The plurality of radar reflectors includes at least three radar reflectors.

6. The method according to claim 1, characterized in that, The step of obtaining the radar positioning location of the position detection point using the radar sensor includes: The distance between the position detection point and the radar reflector, and the angle between the radar reflector and the robot's direction of travel are obtained using the radar sensor. The radar positioning position of the location detection point is determined based on the distance, the included angle, and the heading angle of the robot at the location detection point.

7. The method according to claim 6, characterized in that, The robot's heading angle at the location detection point is set to be obtained in the following manner: Based on the robot's pose data acquired by the inertial sensor, the heading angle of the robot at the position detection point is determined.

8. The method according to claim 6, characterized in that, The step of obtaining the angle between the radar reflector and the robot's direction of travel using the radar sensor includes: The radar sensor is used to obtain the moment when the robot sends a signal to the radar reflector at the location detection point. Based on the correlation between the time when the radar sensor sends a signal and the angle of signal transmission, the angle between the radar reflector and the robot's direction of travel is determined.

9. The method according to claim 1, characterized in that, The step of obtaining the radar positioning location of the position detection point using the radar sensor includes: The distances between multiple consecutive detection points and radar reflectors are obtained respectively; Determine the angle between the radar reflector and the robot's direction of travel at the plurality of consecutive detection points; The relative positions between adjacent position detection points are determined based on the distances between the multiple consecutive position detection points and the radar reflector, as well as the angle between the radar reflector and the robot's travel direction.

10. The method according to claim 9, characterized in that, Determining the relative positions between adjacent position detection points based on the distances between the multiple consecutive position detection points and the radar reflector, and the angle between the radar reflector and the robot's travel direction, includes: Based on the distances between the multiple consecutive position detection points and the radar reflector, and the angle between the radar reflector and the robot's direction of travel, the relative distances between adjacent position detection points are determined. The relative positions of adjacent detection points are determined based on the relative distance between them and the direction of travel of the robot.

11. The method according to any one of claims 4, 6 or 9, characterized in that, The radar reflector is positioned on the boundary of the robot's working area.

12. The method according to any one of claims 4, 6 or 9, characterized in that, The radar reflectors include obstacles within the robot's working area.

13. A robot, characterized in that, include: The robot body includes a movement module, an energy module, a control module, and a function module. The movement module includes a wheel set and a drive motor to drive the wheel set. The energy module includes a battery pack for powering the robot's movement. The function module is used to realize the robot's purpose. The control module is electrically connected to the movement module, energy module, and function module to control the robot's movement and operation. Satellite positioning sensors and radar sensors; A processor configured to perform the method of any one of claims 1 to 12.

14. The robot according to claim 13, characterized in that, The robot also includes inertial sensors.

15. The robot according to claim 13, characterized in that, The functional module includes at least one of the following: A cutting function component, including a cutting blade and a motor that drives the cutting blade to operate; Snow removal function components include a snow removal brush and a motor that drives the snow removal brush to operate; The water spraying function components include a water tank, a water gun, and a motor that drives the water gun to operate.

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