A mower navigation method and device, a mower robot and a medium

Abstract

The application discloses a mower navigation method and device, a mower robot and a medium, and relates to the technical field of mowers. The method comprises the following steps: acquiring sensor data of a mower; wherein the sensor data comprises data output by a single-antenna RTK and data output by an inertial measurement unit; judging the motion state of the mower according to the sensor data; and calculating a heading angle based on the motion state, so as to navigate the mower according to the heading angle. According to the technical scheme of the application, a long-term stable heading angle can be obtained by using a low-cost sensor scheme, and the heading angle calculation method is simpler in combination with the motion state of the mower.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of lawn mowers, in particular to a lawn mower navigation method and device, a lawn mower robot and a medium. BACKGROUND

[0002] A lawn mower robot needs to measure accurate position information and attitude information of the lawn mower to complete a parallel mowing task. The heading angle of the lawn mower is an important parameter for ensuring the parallel degree of parallel mowing. Although RTK (Real-time kinematic) modules can measure positioning data with an error range of centimeters, and a consumer-grade IMU (Inertial Measurement Unit) can be used to calculate the roll angle and pitch angle of the lawn mower, the heading angle directly calculated by the consumer-grade IMU will have a large cumulative error when performing a long-time parallel mowing task, resulting in failure of autonomous navigation of the lawn mower.

[0003] At present, in order to provide a long-time accurate heading angle for a lawn mower robot, commonly used methods include measuring the heading angle by using a double-antenna RTK and combining RTK and INS (Inertial Navigation System) navigation. However, the method of using multiple antennas is high in cost and difficult to install; and the alignment process of the heading angle of the RTK and INS combined navigation requires a motion speed of the carrier to be above 1 meter per second, and since the working speed of the lawn mower robot is below 0.5 meters per second, the alignment process cannot be completed, and therefore the method is not suitable for providing a stable and reliable heading angle for the lawn mower robot.

[0004] Therefore, how to provide a solution to the above technical problems is a problem that those skilled in the art need to solve at present. SUMMARY

[0005] Therefore, the purpose of the present application is to provide a lawn mower navigation method, device, lawn mower robot and medium, which can obtain a long-term stable heading angle using a low-cost sensor solution. The specific solution is as follows:

[0006] In a first aspect, the present application discloses a lawn mower navigation method, comprising:

[0007] obtaining sensor data of the lawn mower; wherein the sensor data includes data output by a single-antenna RTK and data output by an inertial measurement unit;

[0008] determining a motion state of the lawn mower according to the sensor data;

[0009] calculating a heading angle based on the motion state, so as to navigate the lawn mower according to the heading angle.

[0010] Optionally, the sensor data of the mower comprises:

[0011] the real-time latitude and longitude data of the mower obtained from the single-antenna RTK output of the mower and the partial velocities of the mower in the directions of the coordinate axes in the navigation coordinate system;

[0012] and the heading angular rate obtained from the inertial measurement unit output of the mower.

[0013] Optionally, the determining the motion state of the mower according to the sensor data comprises:

[0014] determining whether the mower is in a stationary state according to the sensor data;

[0015] or determining whether the mower is in a turning motion state according to the sensor data;

[0016] or determining whether the mower is in a straight motion state according to the sensor data.

[0017] Optionally, the determining whether the mower is in a stationary state according to the sensor data comprises:

[0018] if the heading angular rate obtained from the inertial measurement unit output is not greater than a first preset threshold, determining that the mower is in the stationary state;

[0019] Correspondingly, the calculating the heading angle based on the motion state comprises:

[0020] if the mower is in the stationary state, determining the heading angle of the mower at the current time according to the heading angle of the mower at the previous time.

[0021] Optionally, the determining whether the mower is in a turning motion state according to the sensor data comprises:

[0022] if the heading angular rate obtained from the inertial measurement unit output is not less than a second preset threshold, determining that the mower is in the turning motion state;

[0023] Correspondingly, the calculating the heading angle based on the motion state comprises:

[0024] if the mower is in the turning motion state, obtaining a sampling period of the mower and determining the heading angle of the mower at the current time based on the sampling period and the heading angle of the mower at the previous time and the heading angular rate of the mower at the previous time.

[0025] Optionally, the determining whether the mower is in a straight motion state according to the sensor data comprises:

[0026] if the absolute value of the speed of the mower in each coordinate axis direction output by the single-antenna RTK is not less than a third preset threshold value, and the absolute value of the heading rate output by the inertial measurement unit is not greater than a fourth preset threshold value, it is determined that the mower is in the straight motion state;

[0027] Correspondingly, the heading angle is calculated based on the motion state, including:

[0028] if the mower is in the straight motion state, a preset number of continuous real-time latitude and longitude data output by the single-antenna RTK is collected;

[0029] The real-time latitude and longitude data is converted into coordinate values in the Universal Transverse Mercator Grid System, and the coordinate values are sequentially saved to an RTK data set;

[0030] determine whether the distance between the two coordinate values newly added to the RTK data set is within a preset distance range, if so, perform data cleaning on the RTK data set, then perform linear fitting and determine the slope after linear fitting, based on the slope, the heading angle of the mower at the last time and the heading angle rate at the last time, according to the sampling period of the mower, the first preset heading angle update weight corresponding to the single-antenna RTK and the second preset heading angle update weight corresponding to the inertial measurement unit, determine the heading angle of the mower at the current time; if not, jump to the step of obtaining the sampling period of the mower, and based on the sampling period, the heading angle of the mower at the last time and the heading angle rate at the last time to determine the heading angle of the mower at the current time.

[0031] Optionally, after obtaining the sensor data of the mower, the method further comprises:

[0032] When the single-antenna RTK enters a fixed solution working state, the current data output by the single-antenna RTK is obtained, and the initial heading angle of the mower is determined according to the current data.

[0033] In a second aspect, the application discloses a mower navigation device, comprising:

[0034] a sensor data acquisition module for acquiring sensor data of the mower; wherein the sensor data includes data output by a single-antenna RTK and data output by an inertial measurement unit;

[0035] a motion state determination module for determining the motion state of the mower according to the sensor data;

[0036] A heading angle calculation module is configured to calculate a heading angle based on the motion state, so as to navigate the mower according to the heading angle.

[0037] In a third aspect, the application discloses a mowing robot, comprising a processor and a memory; wherein the memory is configured to store a computer program, the computer program is loaded and executed by the processor to implement the mowing robot navigation method as described above.

[0038] In a fourth aspect, the application discloses a computer readable storage medium configured to store a computer program; wherein the computer program is executed by a processor to implement the mowing robot navigation method as described above.

[0039] The application provides a mowing robot navigation method, comprising: obtaining sensor data of a mowing robot; wherein the sensor data comprises data output by a single-antenna RTK and data output by an inertial measurement unit; determining a motion state of the mowing robot according to the sensor data; and calculating a heading angle based on the motion state, so as to navigate the mowing robot according to the heading angle. It can be seen that the single-antenna RTK and the inertial measurement unit are combined to perform navigation, which not only ensures high precision of navigation, but also reduces the configuration cost of the mowing robot. Further, the motion state of the mowing robot is determined by using the sensor data of the mowing robot, and the heading angle is calculated based on the motion state, so that the heading angle calculation method is simpler, and the navigation failure caused by accumulated error due to long-time execution of the mowing task can be avoided, and a long-term stable heading angle can be obtained.

[0040] In addition, the application provides a mowing robot navigation device, a mowing robot and a storage medium, which correspond to the above-mentioned mowing robot navigation method and have the same effects. BRIEF DESCRIPTION OF DRAWINGS

[0041] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiment or prior art description. Obviously, the drawings in the following description only constitute the embodiments of the application, and for those skilled in the art, other drawings can also be obtained without creative labor based on the provided drawings.

[0042] Figure 1 A mowing robot navigation method flow chart is disclosed in the application;

[0043] Figure 2 A heading angle output schematic diagram is disclosed in the application;

[0044] Figure 3 A mowing robot navigation device structure schematic diagram is disclosed in the application;

[0045] Figure 4A structure diagram of a mowing robot is disclosed in the present application. DETAILED DESCRIPTION

[0046] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0047] Currently, in order to provide a long-term accurate heading angle for a mowing robot, commonly used methods include: double-antenna RTK measurement of the heading angle and RTK and INS combined navigation. However, the double-antenna RTK has a complex structure design, is difficult to install, requires higher performance of the configured module, and has an extra antenna, resulting in higher cost; and the alignment process of the heading angle of the RTK and INS combined navigation requires a motion speed of the carrier to be above 1 meter per second, and since the working speed of the mowing robot is below 0.5 meters per second, it can be seen that the working speed of the mowing robot cannot meet the alignment process of the heading angle of the combined navigation, and therefore, the method is not suitable for providing a stable and reliable heading angle for the mowing robot.

[0048] Therefore, the present application provides a mowing robot navigation scheme, which can obtain a long-term stable heading angle using a low-cost sensor scheme.

[0049] The embodiments of the present application disclose a mowing robot navigation method, referring to Figure 1 as shown, the method comprises:

[0050] Step S11: acquiring sensor data of the mowing robot; wherein the sensor data comprises data output by a single-antenna RTK and data output by an inertial measurement unit.

[0051] In the embodiments of the present application, the single-antenna RTK is used as one of the sensors of the mowing robot to output real-time position data of the mowing robot and component speeds in each coordinate axis direction under a navigation coordinate system. In this way, the single-antenna RTK is used to overcome the problems of the double-antenna RTK, such as complex structure design, higher performance requirement of the configured module, and an extra antenna resulting in higher cost.

[0052] It should be noted that the real-time position data of the mowing robot is real-time latitude and longitude data of the mowing robot, and the real-time position of the mowing robot is acquired through the real-time latitude and longitude data. The navigation coordinate system in which the mowing robot is located can be a northeast celestial coordinate system or a north east terrestrial coordinate system, and is not specifically limited here, and therefore, acquiring the component speeds in each coordinate axis direction under the navigation coordinate system can be acquiring the component speeds in each coordinate axis direction under the northeast celestial coordinate system or acquiring the component speeds in each coordinate axis direction under the north east terrestrial coordinate system.

[0053] In the embodiment of the application, another sensor in the sensor data output by the mower is an inertial measurement unit of the mower, which outputs a heading rate of the mower. In the process of sensor installation, the RTK antenna and the inertial measurement unit (IMU) are fixedly installed at the center of the rear wheel axis of the mower robot. The Z-axis of the IMU is aligned with the heading axis of the mower, and the IMU outputs the heading rate of the mower, and the RTK module outputs the real-time latitude and longitude data of the mower and the directional speed of each coordinate axis of the navigation coordinate system.

[0054] Step S12: determining the motion state of the mower according to the sensor data.

[0055] It can be understood that, since the inertial measurement unit is used in navigation, the positioning calculation is based on motion integration, and the positioning error in the previous positioning result will be accumulated into the current positioning result. At the same time, due to the zero offset of the IMU itself, the final result is that the positioning error will accumulate over time. In the embodiment of the application, the integral of the positioning over time is not calculated by using the inertial measurement unit, but the angle change of the heading angle is measured by the inertial measurement unit to determine the motion state of the mower. Therefore, there is no error factor caused by time accumulation.

[0056] Specifically, when the mower robot performs parallel mowing tasks in autonomous navigation, the mower moves according to a 'bow' trajectory, and the main motion states include a static state, a straight motion state and a turning motion state. According to the sensor data, it is determined whether the mower is in a static state, a turning motion state or a straight motion state.

[0057] Step S13: calculating the heading angle based on the motion state, so as to navigate the mower according to the heading angle.

[0058] It should be noted that, after determining the motion state of the mower according to the sensor data, the heading angle is calculated according to the current motion state of the mower. Before calculating the heading angle, the heading angle needs to be initialized. The embodiment of the application is different from the traditional heading angle initialization process. In the traditional heading angle initialization process, an initialization value of the heading angle is set, and then the heading angle is constantly adjusted to the set initialization value during the initialization process. In the embodiment of the application, the heading angle does not need to be gradually adjusted, but when the single-antenna RTK enters the fixed solution working state, the current data output by the single-antenna RTK is directly obtained, and the initial heading angle of the mower is determined according to the current data.

[0059] For example, in the northeast celestial coordinate system, when the single-antenna RTK enters the fixed solution state, the mower exits the charging pile, and the heading angle ψ0=arctan(VE / VN) of the mower is initialized by the eastward velocity and the northward velocity output by the single-antenna RTK. Wherein, ψ0 is the initial heading angle of the mower, VE is the eastward velocity, and VN is the northward velocity.

[0060] In the first specific embodiment, if the heading angle rate output by the inertial measurement unit is not greater than a first preset threshold, it is determined that the mower is in the static state. At this time, the calculation of the heading angle is determined according to the heading angle of the mower at the last time, to determine the heading angle of the mower at the current time. That is, ψk=ψk-1; wherein ψk-1 is the heading angle of the mower at the k-1 time, and ψk is the heading angle of the mower at the k time.

[0061] In the second specific embodiment, if the heading angle rate output by the inertial measurement unit is not less than a second preset threshold, it is determined that the mower is in the turning motion state. At this time, the calculation of the heading angle is first to obtain the sampling period of the mower, and then to determine the heading angle of the mower at the current time based on the sampling period, the heading angle at the last time and the heading angle rate at the last time. Specifically, ψk=ψk-1+Wk-1*T; wherein ψk-1 is the heading angle of the mower at the k-1 time, ψk is the heading angle of the mower at the k time, Wk-1 is the heading angle rate of the mower at the k-1 time, and T is the sampling period.

[0062] In the third specific embodiment, if the absolute values of the component velocities of the mower in each coordinate axis direction in the navigation coordinate system output by the single-antenna RTK are not less than a third preset threshold, and the absolute value of the heading angle rate output by the inertial measurement unit is not greater than a fourth preset threshold, it is determined that the mower is in the straight motion state. For example, if the navigation coordinate system adopts the northeast celestial coordinate system, when the absolute value of VE or VN output by the single-antenna RTK is greater than or equal to the third preset threshold, and the absolute value of the heading angle rate output by the inertial measurement unit IMU is less than or equal to the fourth preset threshold, it is determined to be in the straight motion state.

[0063] At this time, if the mower is in the straight motion state, the heading angle is calculated based on the motion state. First, a preset number of continuous real-time latitude and longitude data output by the single-antenna RTK is collected. That is, when it is determined that the current mower is in a straight motion state, the collection of continuous N RTK output latitude and longitude data is started. Then, the real-time latitude and longitude data is converted into coordinate values of the Universal Transverse Mercartor Grid System (UTM) coordinate system, and the coordinate values are sequentially saved to the RTK data set.

[0064] Further, the heading angle is calculated using the data in the RTK data set. It can be understood that since the IMU will have a cumulative error caused by time integration, and the cumulative error can be ignored when turning, the heading angle in the straight motion state is calculated to ensure that the mower is parallel during turning. Specifically, it is determined whether the distance between the two coordinate values newly added to the RTK data set is within a preset distance range. If yes, the RTK data set is cleaned, then linear fitting is performed, and the slope after linear fitting is determined. Based on the slope, the heading angle and the heading angle rate of the mower at the last time, according to the sampling period of the mower, the first preset heading angle update weight corresponding to the single-antenna RTK, and the second preset heading angle update weight corresponding to the inertial measurement unit, the heading angle of the mower at the current time is determined. If not, jump to the step of obtaining the sampling period of the mower, and based on the sampling period, the heading angle of the mower at the current time is determined using the heading angle and the heading angle rate of the mower at the last time.

[0065] For example, first, it is calculated whether the distance between the latest two points in the data set is greater than the minimum distance preset range and less than the maximum distance of 1 meter, that is, it is kept within the preset distance range, and the condition is met, and then the following step is continued, otherwise, it is returned, and the heading angle is updated in a manner that does not meet the straight line motion state; that is, if the straight motion state is not met during the data collection process, the heading angle calculation method is: ψk=ψk-1+Wk-1*T. When the distance between the two coordinate values in the RTK data set is within the preset distance range, the RTK data is cleaned and then linear fitting is performed. The purpose of cleaning is to remove coordinate value data in the data set that does not meet the condition and deviates from the condition. At this time, the linear fitting obtains equation B: y=kx+b, and the slope k of the equation is the heading angle ψrtk calculated by the trajectory. Further, the heading angle at time K is ψk=ψk-1+β*(ψrtk-ψk-1)+α*Wk-1*T; wherein ψk-1 is the heading angle of the mower at time k-1, ψk is the heading angle of the mower at time k, Wk-1 is the heading angle rate of the mower at time k-1, T is the sampling period, β is the update weight of the heading angle calculated by the RTK data set, and α is the update weight of the heading angle rate measured by the gyroscope. It should be noted that β and α as update weights in the calculation process can be fixedly set or updated according to actual conditions, and are not limited here.

[0066] As shown in Figure 2 The whole output stable heading angle process schematic diagram is shown. After collecting sensor data, the motion state of the mower is judged, and the heading angle is calculated by distinguishing different motion states. In this way, the heading angle calculation method is simpler in combination with the motion state of the mower. In addition, since the sensor in the mower is based on single-antenna RTK and inertial measurement unit IMU combination, a low-cost sensor scheme can be used to ensure that a long-term stable heading angle can be obtained in the parallel mowing task of the mower.

[0067] The application provides a mower navigation method, including: acquiring sensor data of a mower; wherein the sensor data includes data output by a single-antenna RTK and data output by an inertial measurement unit; judging a motion state of the mower according to the sensor data; and calculating a heading angle based on the motion state, so as to navigate the mower according to the heading angle. It can be seen that the single-antenna RTK and the inertial measurement unit are combined for navigation, which not only ensures the high precision of navigation, but also reduces the configuration cost of the mower. Further, the motion state of the mower is judged by using the sensor data of the mower, and the heading angle is calculated based on the motion state, so that the heading angle calculation method is simpler, and the navigation failure caused by the accumulated error of long-time mowing task can be avoided, and a long-term stable heading angle can be obtained.

[0068] Correspondingly, the application also discloses a mower navigation device, referring to Figure 3 The device comprises:

[0069] a sensor data acquisition module 11, configured to acquire sensor data of the mower; wherein the sensor data comprises data output by a single-antenna RTK and data output by an inertial measurement unit;

[0070] a motion state determination module 12, configured to determine a motion state of the mower according to the sensor data;

[0071] a heading angle calculation module 13, configured to calculate a heading angle based on the motion state, so as to navigate the mower according to the heading angle.

[0072] Wherein, the more specific working process of each module can refer to the corresponding content disclosed in the foregoing embodiments, which will not be repeated here.

[0073] Therefore, through the above scheme of the embodiment, the sensor data of the mower is acquired; wherein the sensor data comprises data output by a single-antenna RTK and data output by an inertial measurement unit; the motion state of the mower is determined according to the sensor data; and a heading angle is calculated based on the motion state, so as to navigate the mower according to the heading angle. It can be seen that the single-antenna RTK and the inertial measurement unit are combined for navigation, which not only ensures high precision of navigation, but also reduces the configuration cost of the mower. Further, the motion state of the mower is determined by using the sensor data of the mower, and the heading angle is calculated based on the motion state, so that the heading angle calculation method is simpler, and the navigation failure caused by the accumulated error of long-time execution of the mowing task can be avoided, and a long-term stable heading angle can be obtained.

[0074] Further, the application also discloses an electronic device, Figure 4 is a structure diagram of a mower robot 20 according to an exemplary embodiment, and the content in the figure cannot be considered as any limitation on the use range of the application.

[0075] Figure 4 A structure diagram of a mower robot 20 is provided in the embodiment of the application. The mower robot 20 can specifically comprise at least one processor 21, at least one memory 22, a power supply 23, a communication interface 24, an input / output interface 25 and a communication bus 26. Wherein, the memory 22 is used to store a computer program, the computer program is loaded and executed by the processor 21, so as to realize the related steps in the mower navigation method disclosed in any of the foregoing embodiments.

[0076] In this embodiment, the power supply 23 is configured to provide working voltage for each hardware device on the lawn mowing robot 20; the communication interface 24 is configured to create a data transmission channel between the lawn mowing robot 20 and external devices, and the communication protocol followed by the communication interface 24 can be any communication protocol applicable to the technical solution of the present application, which will not be specifically limited herein; the input / output interface 25 is configured to obtain external input data or output data to the outside, and the specific interface type can be selected according to the specific application needs, which will not be specifically limited herein.

[0077] In addition, the memory 22 as a carrier of resource storage can be a read-only memory, a random access memory, a magnetic disk or an optical disk, etc., and the resources stored thereon can include an operating system 221, a computer program 222 and data 223, etc., and the data 223 can include various data. The storage mode can be temporary storage or permanent storage.

[0078] The operating system 221 is configured to manage and control each hardware device on the lawn mowing robot 20 and the computer program 222, and can be Windows Server, Netware, Unix, Linux, etc. In addition to the computer program capable of completing the lawn mowing robot navigation method disclosed in any of the preceding embodiments, the computer program 222 can further include a computer program capable of completing other specific work.

[0079] Further, the present application also discloses a computer readable storage medium, which includes a random access memory (RAM), a memory, a read-only memory (ROM), an electrically programmable ROM, an electrically erasable programmable ROM, a register, a hard disk, a magnetic disk or an optical disk, or any other form of storage medium known in the technical field. The computer program is executed by the processor to implement the aforementioned lawn mowing robot navigation method. For the specific steps of the method, please refer to the corresponding content disclosed in the preceding embodiments, which will not be described here.

[0080] Each embodiment in the specification is described in a progressive manner, and each embodiment focuses on the difference from other embodiments. The same or similar parts between each embodiment can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant part can be referred to the method part.

[0081] The steps of the mower navigation or algorithm described in connection with the embodiments disclosed herein can be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. A software module can reside in random access memory (RAM), memory, read-only memory (ROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art.

[0082] Finally, it should be noted that, in the present document, relational terms such as first and second, and the like can be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises", "comprising", or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without limitation, an element preceded by "comprises... a" does not, without more constraints, foreclose the existence of additional identical elements in the process, method, article, or apparatus.

[0083] The above provides a detailed description of the mower navigation method, device, mower robot and medium provided by the present application. The principles and implementation modes of the present application are described by applying specific examples in the present document. The above description of the embodiments is only used to help understand the method of the present application and its core idea. Meanwhile, for those skilled in the art, according to the idea of the present application, the specific implementation mode and application range will be changed. In summary, the content of the present specification should not be understood as a limitation of the present application.

Claims

1. A lawnmower navigation method, characterized in that, include: Acquire sensor data from the lawnmower; wherein the sensor data includes data output from a single-antenna RTK and data output from an inertial measurement unit; The motion state of the lawnmower is determined based on the sensor data. The heading angle is calculated based on the motion state in order to navigate the lawnmower according to the heading angle; Determining the motion state of the lawnmower based on the sensor data includes: If the heading angular rate output by the inertial measurement unit is not greater than the first preset threshold, the lawnmower is determined to be stationary. If the heading angular rate output by the inertial measurement unit is not less than the second preset threshold, then the lawnmower is determined to be in a turning motion state. If the absolute value of the component velocities of the lawnmower in each coordinate axis direction in the navigation coordinate system output by the single-antenna RTK is not less than the third preset threshold, and the absolute value of the heading angular rate output by the inertial measurement unit is not greater than the fourth preset threshold, then the lawnmower is determined to be in a straight-line motion state. Accordingly, the calculation of the heading angle based on the motion state includes: If the lawnmower is in the stationary state, then the current heading angle of the lawnmower is determined based on the heading angle of the lawnmower at the previous moment; If the lawnmower is in the turning motion state, the sampling period of the lawnmower is obtained, and based on the sampling period, the heading angle of the lawnmower at the current moment is determined by using the heading angle and heading angular rate of the lawnmower at the previous moment. If the lawnmower is in the straight-line motion state, a preset number of consecutive real-time latitude and longitude data output by the single-antenna RTK are collected; The real-time latitude and longitude data is converted into coordinate values ​​in the general transverse Mercka Togo grid system coordinate system, and the coordinate values ​​are sequentially saved to the RTK dataset; If the distance between two coordinate values ​​in the newly added RTK dataset is within a preset distance range, the RTK dataset is cleaned, linearly fitted, and the slope of the linear fit is determined. Based on the slope, the mower's heading angle and angular rate at the previous moment, the current heading angle of the mower is determined according to the mower's sampling period, the first preset heading angle update weight corresponding to the single-antenna RTK, and the second preset heading angle update weight corresponding to the inertial measurement unit. Otherwise, the process jumps to the step of obtaining the mower's sampling period and determining the current heading angle of the mower based on the sampling period and the mower's heading angle and angular rate at the previous moment.

2. The lawnmower navigation method according to claim 1, characterized in that, The acquisition of sensor data from the lawnmower includes: The real-time latitude and longitude data of the lawnmower and the component velocities of the lawnmower in each coordinate axis direction in the navigation coordinate system are obtained from the RTK output of the single antenna of the lawnmower. And, obtain the heading angular rate output by the inertial measurement unit of the lawnmower.

3. The lawnmower navigation method according to claim 1, characterized in that, Determining the motion state of the lawnmower based on the sensor data includes: The sensor data is used to determine whether the lawnmower is stationary. Alternatively, the sensor data can be used to determine whether the lawnmower is in a turning motion. Alternatively, the sensor data can be used to determine whether the lawnmower is in a straight-line motion.

4. The lawnmower navigation method according to any one of claims 1 to 3, characterized in that, After acquiring the sensor data from the lawnmower, the process also includes: When the single-antenna RTK enters the fixed solution working state, the current data output by the single-antenna RTK is acquired, and the initial heading angle of the lawnmower is determined based on the current data.

5. A lawnmower navigation device, characterized in that, include: A sensor data acquisition module is used to acquire sensor data from the lawnmower; wherein, the sensor data includes data output by a single-antenna RTK and data output by an inertial measurement unit; A motion state determination module is used to determine the motion state of the lawnmower based on the sensor data. A heading angle calculation module is used to calculate the heading angle based on the motion state, so as to navigate the lawnmower according to the heading angle; The motion state determination module is specifically used for: If the heading angular rate output by the inertial measurement unit is not greater than the first preset threshold, the lawnmower is determined to be stationary. If the heading angular rate output by the inertial measurement unit is not less than the second preset threshold, then the lawnmower is determined to be in a turning motion state. If the absolute value of the component velocities of the lawnmower in each coordinate axis direction in the navigation coordinate system output by the single-antenna RTK is not less than the third preset threshold, and the absolute value of the heading angular rate output by the inertial measurement unit is not greater than the fourth preset threshold, then the lawnmower is determined to be in a straight-line motion state. Accordingly, the heading angle calculation module is specifically used for: If the lawnmower is in the stationary state, then the current heading angle of the lawnmower is determined based on the heading angle of the lawnmower at the previous moment; If the lawnmower is in the turning motion state, the sampling period of the lawnmower is obtained, and based on the sampling period, the heading angle of the lawnmower at the current moment is determined by using the heading angle and heading angular rate of the lawnmower at the previous moment. If the lawnmower is in the straight-line motion state, a preset number of consecutive real-time latitude and longitude data output by the single-antenna RTK are collected; The real-time latitude and longitude data is converted into coordinate values ​​in the general transverse Mercka Togo grid system coordinate system, and the coordinate values ​​are sequentially saved to the RTK dataset; If the distance between two coordinate values ​​in the newly added RTK dataset is within a preset distance range, the RTK dataset is cleaned, linearly fitted, and the slope of the linear fit is determined. Based on the slope, the mower's heading angle and angular rate at the previous moment, the current heading angle of the mower is determined according to the mower's sampling period, the first preset heading angle update weight corresponding to the single-antenna RTK, and the second preset heading angle update weight corresponding to the inertial measurement unit. Otherwise, the process jumps to the step of obtaining the mower's sampling period and determining the current heading angle of the mower based on the sampling period and the mower's heading angle and angular rate at the previous moment.

6. A lawnmower robot, characterized in that, The lawnmower robot includes a processor and a memory; wherein the memory is used to store a computer program, which is loaded and executed by the processor to implement the lawnmower navigation method as described in any one of claims 1 to 4.

7. A computer-readable storage medium, characterized in that, Used to store computer programs; wherein the computer programs, when executed by a processor, implement the lawnmower navigation method as described in any one of claims 1 to 4.

Images