Disclosure of Invention
In order to solve the defects and shortcomings in the prior art, the invention provides a method for drawing a route based on the prior navigation technology and a geomagnetic navigation scheme respectively, comparing the two routes, and judging whether a geomagnetic sensor is available in the current environment or not based on the error obtained by comparison.
Specifically, the usability detection method for the geomagnetic sensor in the intelligent mower provided by the application comprises the following steps:
acquiring a real-time position of the intelligent mower based on the existing navigation mode, and drawing an actual travelling route of the intelligent mower based on the real-time position;
in the process that the intelligent mower carries out mowing operation along an actual travelling route, acquiring geomagnetic data acquired by a geomagnetic sensor installed in the intelligent mower in real time, and drawing the geomagnetic travelling route of the intelligent mower based on the geomagnetic data;
and comparing the geomagnetic travelling route with the actual travelling route, and if the error value obtained by comparison is greater than a threshold value, judging that the geomagnetic sensor is unavailable in the current working environment.
Optionally, the obtaining a real-time position of the intelligent mower based on the existing navigation manner, and drawing an actual traveling route of the intelligent mower based on the real-time position include:
acquiring the real-time position of the intelligent mower at preset intervals based on the existing navigation mode;
connecting the real-time positions acquired within a preset time period to obtain a theoretical advancing route of the intelligent mower;
and correcting the theoretical advancing route based on the steering parameters of the intelligent mower to obtain a corrected actual advancing route.
Optionally, the correcting the theoretical traveling route based on the steering parameter of the intelligent mower to obtain a corrected actual traveling route includes:
determining steering parameters of the intelligent mower based on the size of the body of the intelligent mower and the steering angle;
and selecting error nodes which cannot be realized by the intelligent mower in the theoretical advancing route according to the steering parameters, deleting the error nodes, and performing curve fitting on the deleted missing route to obtain the corrected actual advancing route.
Optionally, in the process of mowing along the actual travelling route by the intelligent mower, acquiring, in real time, geomagnetic data acquired by a geomagnetic sensor installed in the intelligent mower, and drawing the geomagnetic travelling route of the intelligent mower based on the geomagnetic data, the method includes:
in the process of mowing along an actual travelling route by the intelligent mower, acquiring geomagnetic data which is output by a geomagnetic sensor and represents the travelling direction and travelling speed of the intelligent mower, wherein the geomagnetic data is installed in the intelligent mower at preset time intervals;
and drawing a geomagnetic travelling route of the intelligent mower based on the known travelling direction and travelling speed.
Optionally, the plotting a geomagnetic travel route of the intelligent lawn mower based on the known travel direction and travel speed includes:
determining a traveling direction and a traveling distance of the intelligent mower relative to the previous moment according to the time interval for acquiring the geomagnetic data and the traveling speed in the geomagnetic data in the previous moment;
and accumulating the travelling direction and the travelling distance of the intelligent mower in at least two time periods to finish the drawing of the geomagnetic travelling route of the intelligent mower.
Optionally, the existing navigation mode comprises
Real-time dynamic positioning, and or inertial navigation.
The technical scheme provided by the invention has the beneficial effects that:
the method for verifying the geomagnetic navigation by taking other navigation methods as samples can effectively judge whether the current environment can interfere with the geomagnetic navigation, thereby accurately verifying the effectiveness of the geomagnetic navigation mode.
Detailed Description
To make the structure and advantages of the present invention clearer, the structure of the present invention will be further described with reference to the accompanying drawings.
Example one
The geomagnetic sensor is a very useful sensor in the design of an intelligent mower control system, the heading angle of a machine can be obtained through the geomagnetic sensor (compass principle), and the geomagnetic sensor can also be used for correcting the drift of an inertial element, but the geomagnetic sensor is easily interfered by other magnetic field environments, so that the geomagnetic sensor is not available.
In order to verify whether the geomagnetic sensor is effective in the current working environment, the usability detection method for the geomagnetic sensor in the intelligent lawn mower, as shown in fig. 1, includes:
11. acquiring a real-time position of the intelligent mower based on the existing navigation mode, and drawing an actual travelling route of the intelligent mower based on the real-time position;
12. in the process that the intelligent mower carries out mowing operation along an actual travelling route, acquiring geomagnetic data acquired by a geomagnetic sensor installed in the intelligent mower in real time, and drawing the geomagnetic travelling route of the intelligent mower based on the geomagnetic data;
13. and comparing the geomagnetic travelling route with the actual travelling route, and if the error value obtained by comparison is greater than a threshold value, judging that the geomagnetic sensor is unavailable in the current working environment.
The main idea of the geomagnetic sensor availability detection method provided by the application is that an existing mature navigation method is used as a standard sample, an error value existing between geomagnetic navigation data and the standard sample is obtained, and if the error value exceeds a threshold value representing an acceptable range, it represents that the current geomagnetic environment has too much interference on a geomagnetic sensor, and navigation cannot be performed based on geomagnetic data generated by the geomagnetic sensor, that is, the geomagnetic sensor is unavailable at this time.
It should be noted that the comparison in step 13 may be a comparison between the actual travel route and the geomagnetic travel route by sampling the coordinates of the key points, or a comparison between the overall route shapes of the two travel routes.
Existing navigation approaches include Real-time kinematic (RTK) carrier-phase differential techniques, or inertial navigation, and combinations thereof. By means of a positioning technology or an inertial navigation method, a real-time travelling route of the intelligent mower based on the existing navigation mode and a geomagnetic travelling route under geomagnetic navigation are calculated, and whether geomagnetic navigation is effective or not is judged based on an error value obtained by comparing the two travelling routes. And as another implementation mode, the heading angles of the intelligent mower in different navigation modes can be calculated, the heading angle data obtained in the two navigation modes are compared, and the reliability of the data of the geomagnetic sensor is analyzed, so that whether the geomagnetic sensor is available in the environment or not is judged.
Firstly, the scheme for comparing whether the geomagnetic sensor is available or not based on the travel route is as follows:
the content realized in the step 11 is to draw an actual traveling route of the intelligent mower based on the existing navigation mode, and specifically comprises the following steps:
111. acquiring the real-time position of the intelligent mower at preset intervals based on the existing navigation mode;
112. connecting the real-time positions acquired within a preset time period to obtain a theoretical advancing route of the intelligent mower;
113. and correcting the theoretical advancing route based on the steering parameters of the intelligent mower to obtain a corrected actual advancing route.
According to the implementation manner shown in step 111-113, the real-time positions of the intelligent mower in a plurality of time periods are obtained, and all the real-time positions are connected to obtain the theoretical travel route of the intelligent mower in all the time periods. However, in consideration of the inevitable error of the theoretical travel route obtained based on the navigation information, the theoretical travel route is taken as a sample for subsequent comparison, and therefore the theoretical travel route needs to be corrected so as to obtain an actual travel route more conforming to the actual travel path of the intelligent lawn mower.
The process of correcting the theoretical travel route comprises the following steps:
1131. determining steering parameters of the intelligent mower based on the size of the body of the intelligent mower and the steering angle;
1132. and selecting error nodes which cannot be realized by the intelligent mower in the theoretical advancing route according to the steering parameters, deleting the error nodes, and performing curve fitting on the deleted missing route to obtain the corrected actual advancing route.
Considering that the position where an error may exist is a turn, it is important here to correct the turning portion in the theoretical travel route. The correction method comprises the steps of determining the minimum turning radius which can be realized by the intelligent mower based on the size of the intelligent mower and the steering angle of a steering wheel, deleting wrong nodes with turning radii obviously smaller than the minimum turning radius in a theoretical advancing route, and carrying out curve fitting processing based on actual coordinate values on a discontinuous route obtained after deletion, so as to finally obtain an actual advancing route which is more in line with the advancing mode of the intelligent mower.
Step 12 provides the content of plotting the geomagnetic travel route based on the geomagnetic data obtained by the geomagnetic sensor, which specifically includes:
121. in the process of mowing along an actual travelling route by the intelligent mower, acquiring geomagnetic data which is output by a geomagnetic sensor and represents the travelling direction and travelling speed of the intelligent mower, wherein the geomagnetic data is installed in the intelligent mower at preset time intervals;
122. and drawing a geomagnetic travelling route of the intelligent mower based on the known travelling direction and travelling speed.
The geomagnetic data which can be generated by the geomagnetic sensor comprises a traveling direction and a traveling speed which represent the traveling state of the intelligent mower, and the traveling direction and the traveling distance relative to the intelligent mower at the previous moment are determined according to the time interval for acquiring the geomagnetic data and the traveling speed in the geomagnetic data at the previous moment; and accumulating the travelling direction and the travelling distance of the intelligent mower in at least two time periods to finish the drawing of the geomagnetic travelling route of the intelligent mower.
In addition, comparing whether the geomagnetic sensor is available or not based on the heading angle data is to replace the traveling route in the scheme with a heading angle, and whether the difference value between the heading angle obtained by the existing navigation at a plurality of sampling moments and the heading angle obtained by the geomagnetic navigation is larger than a threshold value is taken as a basis for judging whether the geomagnetic sensor is available or not in the current environment.
The sequence numbers in the above embodiments are merely for description, and do not represent the sequence of the assembly or the use of the components.
The above description is only exemplary of the present invention and should not be taken as limiting the invention, as any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.