Patent Application
20230305575
The present disclosure claims priority of Chinese Patent Application No. CN202011336257.6, filed on November, 25, 2020, entitled “Automatic generation method for robot return-to-base code”, the contents of which are hereby incorporated by reference in its entirety.
The disclosure relates to the technical field of robot navigation and distance measurement, in particular to an environment boundary construction method based on a remote sensor and a mobile robot.
In recent years, robots having automatic action functions, such as common household cleaning sweepers are blooming. At present, common simultaneous localization and mapping (slam) technologies include visual navigation, laser navigation and inertial navigation. Compared with the other two technologies, laser navigation can bring better user experience because a room outline can be scanned in advance to be visually presented in a user interface. However, it has a defect that a rotary laser mechanism is required, such that cost is relatively higher, and a hollow or a protrusion is required on a mold.
According to the disclosure, on the basis that light detection and ranging is not required to rotationally scan an environment outline, only according to physical boundary information which is sensed and marked by a remote sensor on a side surface of a robot, a room outline may be acquired in advance. The specific technical solution is as follows:
An environment boundary construction method based on a remote sensor includes: step 1, starting a mobile robot, and then controlling the mobile robot to rotate, so as to enable the mobile robot to mark exploration boundaries according to sensed distance information of the remote sensor; step 2, marking a local boundary according to a sensed distance of the remote sensor on the same side surface of the mobile robot when the mobile robot advances in a preset planned direction after the mobile robot completes rotation, where the preset planned direction is selected and configured from directions of all the marked exploration boundaries; and step 3, delimiting environment boundaries of an effective distance measurement area of the mobile robot by the local boundary and the exploration boundaries, where at least one remote sensor is arranged on a side surface of a body of the mobile robot.
Optionally, after the step 3, the method further includes: in the case that it is determined that the degree of overlap between the environment boundaries delimited in the step 3 and outline boundaries of the same area on a historical map do not conform to a preset map overlap ratio, calling position and orientation information of the outline boundaries of the same area for adjustment, specifically, rotating and translating the environment boundaries delimited in the step 3 to adjust the degree of overlap between the environment boundaries delimited in the step 3 and the outline boundaries of the same area on the historical map to conform to the preset map overlap ratio, so as to supplement boundaries of distance detection blind areas of the remote sensor on the basis of the environment boundaries. The distance detection blind areas go beyond an effective detection distance of the remote sensor. The historical map is a grid map of environment boundaries pre-marked and delimited by the mobile robot in the same effective distance measurement area.
Optionally, the preset map overlap ratio includes a preset position and orientation difference. In the case that the degree of overlap between the environment boundaries delimited in the step 3 and the outline boundaries of the same area on the historical map do not conform to the preset map overlap ratio, a difference between a position and orientation of the environment boundaries delimited in the step 3 and a position and orientation the outline boundaries of the same area on the historical map is greater than the preset position and orientation difference.
Optionally, between the step 1 and the step 2, the method further includes: in the case that the mobile robot selects an exploration sub-boundary from the exploration boundaries marked by means of the rotation in the step 1, after the mobile robot completes rotation in the step 1, controlling the mobile robot to advance in an extending direction of a direction of the exploration sub-boundary. The preset planned direction of the mobile robot in the step 2 is parallel to the extending direction of the exploration sub-boundary. The exploration boundaries include the exploration sub-boundary, and the exploration sub-boundary is selected for planning a traveling direction of the mobile robot.
Optionally, in the case that the exploration sub-boundary is a linear boundary, the mobile robot is controlled to advance in an extending direction of the linear boundary, such that the preset planned direction in the step 2 is a linear direction. Then the mobile robot is controlled to advance in the linear direction in the step 2 and mark a local boundary on a fixed side of the linear direction according to the sensed distance of the remote sensor arranged on the same side surface of the mobile robot. When the mobile robot advances in the linear direction, a detection direction of the remote sensor is unique and fixed. The extending direction of the linear boundary is a linear direction.
Optionally, in the case that the exploration sub-boundary is a curved boundary, the mobile robot is controlled to advance in a direction of the curved boundary, such that after the mobile robot proceeds to the step 2, the preset planned direction is a curved direction. Then the mobile robot is controlled to advance in the curved direction and mark a local boundary on a fixed side of the curved direction according to the sensed distance of the remote sensor arranged on the same side surface of the mobile robot. When the mobile robot advances in the curved direction, a detection direction of the remote sensor is not unique. An extending direction of the curved boundary is a curved direction.
Optionally, when the mobile robot advances in the preset planned direction, in the case that the remote sensor does not sense distance information of an obstacle within the effective detection distance, a direction of the local boundary marked in the step 2 is parallel to the preset planned direction. A line distance between a path on which the mobile robot travels for marking the local boundary and the local boundary is equal to the effective detection distance, and a projection of the path on which the mobile robot travels for marking the local boundary on the local boundary overlaps the local boundary.
Optionally, when the mobile robot advances in the preset planned direction, in the case that the remote sensor senses the distance information of the obstacle within the effective detection distance, the local boundary marked in the step 2 is an outline of a corresponding side of the obstacle, and the corresponding side of the obstacle is a side surface reflecting a detection signal of the remote sensor. A linear distance between a body center of the mobile robot and a boundary point of the local boundary marked in real time is less than or equal to the effective detection distance.
Optionally, after the local boundary is marked on a grid map instantly constructed by the mobile robot, the mobile robot is controlled to transmit the grid map with the marked local boundary to a visual mobile terminal by means of wireless/wired signals such that the visual mobile terminal may display an area delimited by means of the local boundary to a user.
A mobile robot includes a processing unit. At least one remote sensor is mounted on a side surface of a body of the mobile robot, and the processing unit is used for executing a program corresponding to the above environment boundary construction method.
Optionally, a mounting position of the remote sensor is in a direction perpendicular to an advancing direction of the mobile robot, where a detector direction of the remote sensor is in the direction perpendicular to the advancing direction of the mobile robot, or the detector direction of the remote sensor forms a preset detection angle relative to the advancing direction of the mobile robot; alternatively the mounting position of the remote sensor is on an advancing plane of the mobile robot and forms an inclined mounting angle relative to the advancing direction of the mobile robot, where the detector direction of the remote sensor is in the direction perpendicular to the advancing direction of the mobile robot, or the detector direction of the remote sensor forms a preset detection angle relative to the advancing direction of the mobile robot. The remote sensor is used for measuring distance information of the environment boundaries (including the exploration boundaries and the local boundary in the above technical solutions) on the fixed side of the advancing direction of the mobile robot.
Optionally, the mobile robot includes at least two remote sensors. The two remote sensors are arranged on a left side surface and a right side surface of a body of the mobile robot respectively, have detection directions both perpendicular to the advancing direction of the mobile robot, and are used for measuring distance information of obstacles on a left side and a right side of the mobile robot on the advancing plane of the mobile robot simultaneously. The advancing direction of the mobile robot points to a front end of the body of the mobile robot.
Optionally, the remote sensor is mounted on a front half side surface or a rear half side surface of a body of the mobile robot. The front half side surface and the rear half side surface of the mobile robot are separated by a central axis passing through a body center of the mobile robot, and the central axis is perpendicular to the advancing direction of the mobile robot.
The technical solutions in the embodiments of the disclosure will be described in detail below with reference to the accompanying drawings in the embodiments of the disclosure.
An embodiment of the disclosure discloses an environment boundary construction method based on a remote sensor. In order to acquire room outline information without using light detection and ranging to rotationally scan environment outlines, the environment boundary construction method only uses a remote sensor on a side surface of a robot to mark physical boundary information, so as to acquire a room outline in advance. The specific steps include:
step 1, start a mobile robot, specifically, carry out power on to start the mobile robot or awaken the mobile robot from a dormant state, and then control the mobile robot to rotate a preset number of times at an initial position, so as to enable the mobile robot to sense distance information of an obstacle within an effective detection distance with a current position of the mobile robot as a center by means of a remote sensor, and distance information on the premise that no obstacle is detected, and then correspondingly mark exploration boundaries within the effective detection distance with the current position of the mobile robot as the center on a grid map. Actually, boundary points of sensed distances of the remote sensor less than or equal to the effective detection distance are marked on the grid map by the mobile robot, and grids where the boundary points are positioned are connected to form the exploration boundaries, and the boundary points are within an effective distance measurement area of the current position of the mobile robot. It should be noted that distances between the initial position of the mobile robot or a body center of the mobile robot and the boundary points of the exploration boundaries are regarded as the sensed distances acquired when the remote sensor of the mobile robot maintains rotating at the initial position. The mobile robot may acquire 360-degree environment distance information within the effective detection distance with the initial position of the mobile robot as the center when rotating, which belongs to relatively rough local area boundary information in a map exploration stage, such that it is necessary to proceed to step 2 to supplement boundary points and to adjust and perfect position coordinate information. In the step 1, the remote sensor for distance measurement may be arranged on a left side surface or a right side surface of a body of the mobile robot; or the remote sensors may be arranged on a left side surface and a right side surface of the body of the mobile robot.
It should be noted that the remote sensor may be a single-point time of flight (TOF) position sensor or a position sensitive detector (PSD) suitable for remote detection, but not light detection and ranging. The remote sensor is used for acquiring distance information between an obstacle within an effective detection distance range and the mobile robot, and the distance information is converted into angle distance obstacle information in an angle direction on a grid map to serve as map boundary information to be provided for the mobile robot for navigation and planning.
In the embodiment, the effective detection distance of the remote sensor is a distance measurement distance greater than 1 meter, and in some implementation scenarios, the effective detection distance of the remote sensor is generally required to be greater than 4 meters.
In the embodiment, at least one remote sensor is arranged on a side surface of the body of the mobile robot, a mounting position of the remote sensor is in a direction perpendicular to an advancing direction of the mobile robot, where a detector direction of the remote sensor is in the direction perpendicular to the advancing direction of the mobile robot, or the detector direction of the remote sensor forms a preset detection angle relative to the advancing direction of the mobile robot. The preset detection angle satisfies measurement of distance information on any side of the advancing direction of the mobile robot.
In another embodiment, the mounting position of the remote sensor is on an advancing plane of the mobile robot and forms an inclined mounting angle relative to the advancing direction of the mobile robot, where the detector direction of the remote sensor is in the direction perpendicular to the advancing direction of the mobile robot, or the detector direction of the remote sensor forms the preset detection angle relative to the advancing direction of the mobile robot, and the inclined mounting angle is not 90 degrees. However, in this case, measured distance information of the remote sensor subjected to angle conversion may achieve distance measurement and positioning effects the same as that of the remote sensor in the above embodiment.
It should be noted that the remote sensor may be arranged on one side surface of the body of the mobile robot or the remote sensors may be arranged on two side surfaces of the body of the mobile robot. In the case that the remote sensors are mounted on two sides of the body, as shown in
Step 2, when the mobile robot advances in a preset planned direction, control the remote sensor mounted on the same side surface of the mobile robot to sense and mark a local boundary, that is, to connect corresponding grid marks on the grid map into the local boundary according to the distance information sensed by the remote sensor arranged on the same side surface, and then proceed to step 3. The preset planned direction is selected and configured from directions of all marked exploration boundaries, and is used for controlling the mobile robot to continue to carry out distance measurement in a current working area or to start cleaning in an untraversed area. In the step 2, the mobile robot completes rotation in the step 1, acquires local environment information, and then advances in the preset planned direction, where the preset planned direction is an extending direction of a marked boundary selected from the local environment information acquired by means of the rotation, and the extending direction of the boundary means a direction of a line where the exploration boundary is positioned and means a line where the local boundary is positioned. Then, in the embodiment, the remote sensor is used to sense obstacle information on at least one side of the preset planned direction of the robot, and the remote sensor for remote detection on the left side or the right side of the mobile robot may be used to sense the obstacle information on the corresponding fixed side of the preset planned direction. For example, in the step 2, only the remote sensor 106 on the left side of the mobile robot is controlled to sense obstacle boundary distance information (local boundary) in a left direction 107 of the preset planned direction, and in this process, the remote sensor 104 on the right side of the mobile robot may not carry out distance measurement; or in the step 2, only the remote sensor 104 on the right side of the mobile robot is controlled to sense the obstacle boundary distance information (local boundary) in a right direction 105 of the preset planned direction, and in this process, the remote sensor 106 on the left side of the mobile robot may not carry out distance measurement. Therefore, distances between the left side or the right side of the body 101 and local boundaries (including obstacle boundaries and virtual boundaries set due to limited detection distances) are continuously acquired, and the obstacle boundary position information are supplementarily marked on grids within the effective detection distance from a marked grid of the current position of the mobile robot, and the grids are connected into the local boundaries on the grid map. In both the step 1 and step 2, the boundary information is marked on the same grid map.
It should be noted that the above marking step actually belongs to a boundary construction process of the grid map.
Step 3, delimit environment boundaries of an effective distance measurement area of the mobile robot by the local boundary and the exploration boundaries, and mark the environment boundaries on the grid map in the step 2. The effective distance measurement area of the mobile robot is an area (an area not certainly traversed by the mobile robot) covered with the remote sensor when the mobile robot executes the step 1 and the step 2, and may be understood as an indoor room area where the mobile robot executes distance measurement and mapping tasks. When the preset planned direction in the step 2 does not point to a fixed direction, the remote sensor supplements the sensed obstacle boundary distance information by sequentially sensing reflected signals in different directions, and marks a local boundary in a new direction on the grid map in combination with the effective detection distance of the remote sensor. Therefore, complete surrounding boundary information of the current position of the mobile robot may be gradually supplemented on the basis of the above exploration boundaries, overall environment outline characteristics in an effective detection range of the remote sensor may be scanned in advance, such that path planning of the mobile robot may be conveniently carried out.
Compared with the prior art, the technical solution has the effects that in the above step 1 and step 3, when the robot advances, a rotary laser mechanism mounted on a top surface of a body is not required to scan and mark surrounding environment boundaries, and the remote sensor arranged on a side surface is used to mark local boundaries step by step; and then in combination with the exploration boundaries acquired by means of rotation of the remote sensor at the initial position, the delimited environment boundaries of a current effective distance measurement area of the mobile robot instead of boundaries of an actual movement area of the mobile robot are formed, such that the technical effect of acquiring an outline of an indoor untraversed room area in advance is achieved.
As one embodiment, after the step 3, the method further includes: carry out matching and alignment on the environment boundaries delimited in the step 3 with the historical map, specifically, in the case that it is determined that the degree of overlap between the the environment boundaries delimited in the step 3 and outline boundaries of the same area on the historical map do not conform to a preset map overlap ratio, rotate and translate the environment boundaries delimited in the step 3 to adjust the degree of the overlap between the environment boundaries delimited in the step 3 and the outline boundaries of the same area on the historical map to conform to the preset map overlap ratio, which is an adjustment process of position and orientation information of the environment boundaries; in the case that the environment boundaries become the same as the position and orientation information of the outline boundaries of the same area on the historical map, supplement boundaries of distance detection blind areas of the remote sensor on the basis of the environment boundaries; and in the case that the adjusted environment boundaries overlap the outline boundaries of the same area on the historical map within an error allowable range, realize the matching and alignment. The distance detection blind areas go beyond the effective detection distance of the remote sensor, and the position and orientation information of the outline boundaries of the same area on the historical map is environment boundaries of the distance measurement area of the mobile robot marked in the pre-executed step 1 to step 3 by the mobile robot, and is a known grid map. In the embodiment, the known historical map is used for supplementing the boundaries of the detection blind areas which are not be detected due to limitation of a detection distance of the remote sensor, so as to enhance reliability of size and shape information of a map environment area instantly constructed by the mobile robot. It is worth noting that the outline boundaries of the same area on the historical map are sensed and marked by the remote sensor at the same mounting position.
Optionally, the preset map overlap ratio includes a preset position and orientation difference. In the case that the degree of overlap between the environment boundaries delimited in the step 3 and the outline boundaries of the same area on the historical map do not conform to the preset map overlap ratio, a difference between a position and orientation of the environment boundaries delimited in the step 3 and a position and orientation the outline boundaries of the same area on the historical map is greater than the preset position and orientation difference. In the case that the degree of the overlap between the environment boundaries delimited in the step 3 and the outline boundaries of the same area on the historical map conform to the preset map overlap ratio, a difference between a position and orientation of the environment boundaries delimited in the step 3 and a position and orientation the outline boundaries of the same area on the historical map is less than or equal to the preset position and orientation difference, and it is determined that the environment boundaries delimited in the step 3 overlap the outline boundaries of the same area on the historical map. In the embodiment, an overlap degree of the maps is determined according to the difference between the position and orientation of the environment boundaries marked by the remote sensor on the side surface of the mobile robot and the position and orientation of the corresponding boundaries of the historical map, so as to reduce map matching errors, such that position and orientation differences and map matching errors may be minimized in some implementation scenarios.
As one embodiment, between the step 1 and the step 2, the method further includes: in the case that the remote sensor of the mobile robot selects an exploration sub-boundary from the exploration boundaries marked by means of the rotation in the step 1, which is specifically as follows: as shown in
In some implementation scenarios, when it is detected that a current advancing direction of the mobile robot deviates from the extending direction (understood as a direction of the exploration sub-boundary) of the exploration sub-boundary, the current advancing direction of the mobile robot is adjusted to be the extending direction of the exploration sub-boundary, such that the mobile robot maintains advancing in the extending direction of the exploration sub-boundary, where the exploration boundaries include the exploration sub-boundary. Before the mobile robot starts to travel and work in the preset planned direction, the exploration sub-boundary is selected from measured distance information acquired by means of rotation of the remote sensor to provide guiding information of a standard working path direction for the robot, so as to use measured distance information of a local environment included in the exploration sub-boundary to correct the preset planned direction of the mobile robot in the step 2, and further to correct the local boundary marked by the mobile robot when traveling in the preset planned direction.
As shown in
As shown in
In the embodiment of
As one embodiment, as shown in
It should be noted that the local boundaries may be divided into linear boundaries and curved boundaries, and the linear boundaries may be divided into physical boundaries (obstacle boundaries) and virtual boundaries.
Optionally, as shown in
On the basis of the above embodiments, as shown in
Optionally, in the case that the exploration sub-boundary is a curved boundary, the mobile robot is controlled to advance in a direction of the curved boundary, such that after the mobile robot proceeds to the step 2, the preset planned direction is a curved direction. Then the mobile robot is made to advance in the curved direction and mark a local boundary on a fixed side of the curved direction by means of the remote sensor mounted on the same side surface of the mobile robot. When the mobile robot advances in the curved direction, a detection direction of the remote sensor is not unique, and the detection directions of the remote sensor will constantly change along with a tortuous advance of the mobile robot, so as to acquire measured distance information in a plurality of different directions. Compared with a mobile robot in the above embodiment which linearly travels and only acquires measured distance information in a fixed direction, the mobile robot in the embodiment may gradually “supplements” surrounding boundary point measured distance information when traveling in the curve direction, so as to scan relatively complete environment outlines, and further to conveniently carry out more intelligent path planning according to the environment outline information. It should be noted that a marking method of the curved boundaries (curved boundaries may also be divided into physical boundaries (obstacle boundaries) and virtual boundaries) may be determined with reference to a marking method of the linear boundaries in the above embodiment, and will not repeated herein.
In the above embodiment, after the local boundary is marked on the grid map instantly constructed by the mobile robot, the mobile robot is controlled to transmit the grid map with the marked local boundary to a visual mobile terminal by means of wireless/wired signals such that the visual mobile terminal may display an area delimited by means of the local boundary to a user. In the embodiment, all marked local boundaries are marked on the same grid map and may be displayed to a user in an interface form, such that the user may see an outline of a local environment in advance in a map exploration stage of the mobile robot, so as to improve user experience.
An embodiment of the disclosure further discloses a mobile robot. The mobile robot includes a processing unit, at least one remote sensor is mounted on a side surface of a body of the mobile robot, and the processing unit is used for executing a program corresponding to the environment boundary construction method. The mobile robot rotates a body to scan distance information of a local environment at first, the remote sensor arranged on a side surface is used to mark local boundaries step by step, and then in combination with exploration boundaries acquired by means of rotation of the remote sensor at an initial position, delimited environment boundaries of a current effective distance measurement area of the mobile robot are formed, so as to acquire an outline of an indoor room area by means of a distance measurement method which is lower in cost and simpler. Compared with a solution that a laser sensor acquires outline information of environment boundaries by means of rotary laser scanning, the technical solution reduces manufacture cost of the robot, is easy to implement and has excellent expandability.
It should be noted that the processing unit controls operations of the mobile robot, and the processing unit may also be referred to as a central processing unit (CPU). The processing unit may be an integrated circuit chip having a signal sequence processing capability. The processing unit may also be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices and discrete hardware components. The general-purpose processing unit may be a microprocessor, or the processing unit may be any conventional processor, etc. The remote sensor may acquire distance information between an obstacle within a measurement range (equivalent to the above effective detection distance) and the remote sensor, which may also be considered that the remote sensor may acquire distance information between an obstacle within the measurement range (equivalent to the effective detection distance) and the body center of the mobile robot. The processing unit is used for executing instructions, so as to implement the method provided by any embodiment of the environment boundary construction method based on a remote sensor in the disclosure, as well as non-conflicting combinations.
In the embodiment, a mounting position of the remote sensor is in a direction perpendicular to an advancing direction of the mobile robot, where a detector direction of the remote sensor is in the direction perpendicular to the advancing direction of the mobile robot, or the detector direction of the remote sensor forms a preset detection angle relative to the advancing direction of the mobile robot, and the remote sensor is used for measuring distance information of environment boundaries (including the exploration boundaries and the local boundary in the above embodiment) on a fixed side of the advancing direction of the mobile robot; alternatively the mounting position of the remote sensor is on an advancing plane of the mobile robot and forms an inclined mounting angle relative to the advancing direction of the mobile robot, where the detector direction of the remote sensor is in the direction perpendicular to the advancing direction of the mobile robot, or the detector direction of the remote sensor forms a preset detection angle relative to the advancing direction of the mobile robot, and the remote sensor is used for measuring the distance information of the environment boundaries (including the exploration boundaries and the local boundary in the above embodiment) on the fixed side of the advancing direction of the mobile robot. It should be noted that the inclined mounting angle is not 90 degrees, but in this case, the measured distance information of the remote sensor subjected to position and orientation coordinate conversion of a software algorithm may achieve distance measurement and positioning effects the same as that of the remote sensor mounted perpendicular to the advancing direction of the mobile robot.
Optionally, the mobile robot includes at least two remote sensors, as shown in
It should be noted that the remote sensor may be a single-point laser ranging sensor, and may emit a laser ranging ray, where the laser ranging ray may be visible light or invisible light. The laser ranging ray emitted by the remote sensor may irradiate a surface of an obstacle, and a straight line where a direction of a laser beam of the remote sensor is positioned just passes through the body center of the mobile robot in a left-right direction. The effective detection distance of the remote sensor is 4 meters to 50 meters.
Optionally, the remote sensor is mounted on a front half side surface or a rear half side surface of a body of the mobile robot, which correspond to a front side or a rear side of the remote sensor 104 of
Obviously, the above embodiments are merely examples given for clear illustration, and are not intended to limit implementations. For a person of ordinary skill in the pertained field, modifications or variations in other forms may make on the basis of the above description. There are no need and no way to exhaust all the implementations. Obvious modifications or variations derived shall still fall within the protection scope of the disclosure.
| Number | Date | Country | Kind |
|---|---|---|---|
| 202011336257.6 | Nov 2020 | CN | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/CN2021/120083 | 9/24/2021 | WO |
