CN113110473B - Connectivity-based region judging method, chip and robot - Google Patents

Abstract

The invention discloses a region judging method based on connectivity, a chip and a robot, wherein the region judging method controls the robot to conduct connected region search on a known grid of a neighborhood from the view of the accessibility of the robot, the connectivity is identified in the known grid region from the near to the far in a connected region searching mode, and then the connectivity is identified in all types of grid regions from the near to the far in a connected mode, the method comprises the steps that a local map constructed at the current position of the robot is adjacently communicated with the known map region, the local map constructed at the current position of the robot is overlapped with the known map region, the local map constructed at the current position of the robot is not communicated with the known map region, and therefore whether the current position of the robot is communicated with the known map region at a corresponding distance or not is comprehensively judged, and whether the current position of the robot is in the known map region or not is judged.

Description

Connectivity-based region judging method, chip and robot

Technical Field

The invention relates to the technical field of robot map searching, in particular to a region judging method based on connectivity, a chip and a robot.

Background

In the prior art, in order to enable a robot to be restarted when being moved to a new position or to be capable of positioning itself when being started, the adopted technology is called SLAM (simultaneous localization AND MAPPING, synchronous positioning and mapping) technology, so as to realize the position positioning of the mobile device in an unknown environment, and the robot performs self positioning according to position estimation and a map in the moving process.

However, in a strange environment, the robot often needs to explore an unknown area, and some indoor environments are complex, so that a pre-established map and a currently constructed map are relatively discretely distributed, and therefore, the robot searches out an area supporting actual traffic in the strange environment comprehensively, which is a technical problem to be solved at present.

Disclosure of Invention

In order to solve the technical defects, the area judging method based on connectivity, the chip and the robot are suitable for the robot before navigation and movement, and help the robot to judge whether the current position or the local map built by the robot is communicated with other known areas. The specific technical scheme comprises the following steps:

A connectivity-based region judgment method, the region judgment method comprising: step 1, searching a connected domain by searching the nearest known grid in the neighborhood until judging that the latest searched known grid meets a first area passing condition, and determining that the current position of the robot is communicated with a preset known grid area, wherein a local map constructed at the current position of the robot is not overlapped with the preset known grid area; step 2, after searching all the known grids within the longest distance which can be reached by the robot through the connected domain search in the step 1, if the latest searched known grids are judged not to meet the first area passing condition, entering the step 3; step 3, searching a connected domain by searching the nearest grid in the neighborhood until judging that the latest searched known grid meets a second area passing condition, and determining that the current position of the robot is not connected with a preset known grid area; step 4, after searching all grids within the farthest distance which can be searched by the robot through the connected domain searching in the step 3, if the latest searched known grid does not meet the second area passing condition, determining that the current position of the robot is communicated with a preset known grid area, wherein a local map constructed at the current position of the robot overlaps the preset known grid area; wherein the preset known grid region is a map region constructed and stored in the same motion region by the robot before the region determination method is performed.

Compared with the prior art, the region judging method controls the robot to conduct connected domain searching on the known grids of the neighborhood from the accessibility angle of the robot, and identifies connectivity in the known grid region from the near to the far in a connected domain searching mode, and then identifies connectivity in all types of grid regions from the near to the far in a connected mode, wherein the method comprises the steps that a local map constructed at the current position of the robot is adjacently communicated with the known map region, the local map constructed at the current position of the robot is overlapped with the known map region, and the local map constructed at the current position of the robot is not mutually communicated with the known map region, so that whether the current position of the robot is communicated with the known map region at the corresponding distance is comprehensively judged, and whether the current position of the robot is in the known map region is judged.

Further, the robot builds a local map at its current position, this local map being specifically: the grids in the area with the current position of the robot as a circle center and the preset detection length as a radius are marked as known grids; the preset detection length is smaller than or equal to the diameter of the robot body; among them, known grids include barrier-free grids and barrier grids. According to the technical scheme, the robot is controlled to establish a real-time effective map-establishing area of the robot with the radius smaller than or equal to the diameter of the robot body by taking the center of the robot body as the center of the circle, so that a minimum effective detection area near the robot body is formed, and the minimum effective detection area is a known grid for supporting the robot to pass through.

Further, the first area passing condition is met, that is, the length of a line segment between the current position of the robot and the known grid searched in the step 1 is larger than the diameter of the body of the robot. And (2) enabling the first area passing condition to be met when the length of a line segment between the current position of the robot and the known grid searched in the step (1) is larger than the diameter of the robot body or the diameter of the robot body, wherein the detectable distance range or the reachable distance range of the robot is larger than the diameter of the robot body or the diameter of the robot body, and the map area built by the robot is communicated with the preset known grid area built in advance outside.

Further, in the step 1, the method step of searching the connected domain by searching the nearest known grid in the neighborhood specifically includes: step 11, screening a grid closest to the current searching position of the robot from a first storage space created in advance, determining the screened grid as the latest searched known grid in the step 1 or the step 2, and then entering the step 12; wherein the pre-created first storage space stores a known neighborhood grid of the current search position of the robot, the known neighborhood grid of the current search position of the robot being a known grid in the neighborhood grids of the current search position of the robot; step 12, storing grid information of the current searching position of the robot into a pre-created second storage space to be stored as a searched target grid; in the neighborhood grids of the grids screened in the step 11, storing grid information of the known grids into a first storage space created in advance so as to be stored as target grids to be searched; meanwhile, updating the searching radius of the robot to be the length of a line segment between the current position of the robot and the grid screened in the step S11; the neighborhood grids of the current searching position of the robot are corresponding to 8 adjacent grids on a grid map built by the robot in real time by taking the current searching position of the robot as a center, and the known grids in the 8 grids are known neighborhood grids; the grid screened in step 11 does not belong to the grid of the repeated screening. According to the technical scheme, the known grids are searched in the eight neighborhood with the current searching position of the robot as the center, the known grids with the shortest path characteristics are searched to serve as target grids to be searched, the reachable distance information of the robot is expanded, meanwhile, the searched known grids are stored to distinguish the searched area and the non-searched area of the robot, the purpose of quickly searching the connected area formed by the connection of the known grids in the local area is achieved, and whether the current position of the robot directly reaches the preset known grid area is accelerated.

Further, before executing the step 11, the method further includes: after the first storage space is created for storage, grid information of the current position of the robot is stored in the first storage space, and the current position of the robot is configured as the current searching position of the robot; screening grids closest to the current searching position of the robot from the first storage space, so that the current position of the robot is screened out from the first storage space and becomes the grids closest to the current searching position of the robot; then, storing the grid information of the current position of the robot into the second storage space, and storing the grid information of the known grids in the neighborhood grids of the current position of the robot into the first storage space; the first storage space created in advance is a memory space supporting grid information caching according to a first-in first-out sequence. According to the technical scheme, the current position of the robot is preferentially used as a searching starting point of the connected domain, and the current position is of course a last grid information, so that the effectiveness and the order of searching adjacent connected domains are improved.

Further, the step 1 specifically includes: repeating the steps 11 and 12 until the length of the line segment between the current position of the robot and the known grid searched by the step 11 is larger than the diameter of the robot body; before re-executing the step 11, updating the current search position of the robot by using the grid which is closest to the current search position of the robot and is not repeatedly searched and is screened out in the step 11; when detecting that the grid information of the grid screened in the step 11 does not appear in the second storage space, the grid participating in the detection is a grid which is not searched repeatedly; when detecting that the grid information of the grid screened in the step 11 appears in the second storage space, the grid participating in the detection is a grid which is repeatedly searched.

According to the technical scheme, a new known grid (the known grid which is not repeatedly searched) is searched in an eight neighborhood with the current searching position of the robot as the center, the current searching position of the robot is updated, the step 11 and the step 12 are repeatedly executed to update the current searching position of the robot, the reachable area formed by the communication of the known grids with the shortest path characteristic is searched, the reachable distance information of the robot is expanded one by one of the known grids, all the known grids in the farthest area reachable by the robot are not obtained until the first area passing condition is met, and the communication relation between the current position of the robot and the preset known grid area is rapidly identified in the near-distance area.

Further, in the step 1, the method further includes: repeatedly executing the step 11 and the step 12 until all the known grids in the longest distance reachable by the robot are searched when the latest searched known grids keep not meeting the first area passing condition and the pre-created first storage space is empty; wherein the furthest distance reachable by the robot is the maximum said search radius obtained by updating during execution of step 12. In the technical scheme, in the process of repeatedly executing the step 11 and the step 12, the condition that all the known grid searches in the furthest region reachable by the robot are finished is established.

Further, after finishing executing step 2, before starting executing step 3, the first storage space and the second storage space are emptied. Since the robot needs to execute step 3 to further search all the mark type grids in the neighborhood and guide and judge whether the preset known grid area is searched or not on the basis of the mark type grids, the grid information stored by searching only the known grids in the previous step is emptied so as to avoid influencing the searching range due to repeated searching.

Further, the second area passing condition is met, that is, the length of a line segment between the current position of the robot and the known grid searched in the step 3 is larger than the diameter of the body of the robot. The map area for representing the robot constructed at its current position is not in communication with the preset known grid area, the two areas being relatively separated.

Further, in the step 3, the method step of searching the connected domain by searching the nearest grid in the neighborhood specifically includes: step 31, screening a grid closest to the current searching position of the robot from neighbor grids of the current searching position of the robot in a first storage space which is created in advance, and then entering step 32; step 32, storing the grid information of the current searching position of the robot into a pre-created second storage space to be stored as a searched target grid, and storing the grid information of the neighborhood grid of the grid screened in step 31 into a pre-created first storage space to be stored as a target grid to be searched, so that the first storage space stores barrier-free grids, unknown grids and/or barrier grids in the neighborhood of the current position of the robot; when the grid screened in the step 31 is a known grid, determining the grid screened in the step 31 as the latest searched known grid in the step 3 or the step 4; the neighborhood grids of the current searching position of the robot take the current searching position of the robot as a center, 8 grids which are adjacent to each other are corresponding to the grid map which is built immediately by the robot, and the known grids in the 8 grids and the current searching position of the robot form a searched connected domain respectively; the grid screened in step 31 is not a grid that is repeatedly screened.

Compared with the steps 11 to 12 in the technical scheme, the method determines that the connected domain searching mode of searching the new known grids in the eight neighborhood with the current searching position of the robot as the center is not capable of searching the preset known grid area which is communicated with the current position of the robot, and then searches the eight neighborhood with the current searching position of the robot as the center to find the grid with the shortest path characteristic as the target grid to be searched and expands the reachable distance information of the robot, so that the preset known grid area which is not communicated with the preset known grid area which is communicated with the searching small range in all directions can be quickly searched, the constraint of the known grids and the unknown grids is avoided in the process of executing the steps 31 to 32, and the grid searching of the area with a larger range is facilitated, namely, the method is not limited to the marking attribute of the grid.

Further, after the first storage space and the second storage space are emptied, before performing the step 31, the method further includes: firstly, storing grid information of the current position of the robot into the first storage space, and configuring the current position of the robot as the current searching position of the robot; screening grids closest to the current searching position of the robot from the first storage space, so that the current position of the robot becomes the grid closest to the current searching position of the robot; and then storing the grid information of the current position of the robot into the second storage space, and storing all the grid information of the neighborhood grids of the current position of the robot into the first storage space. According to the technical scheme, the current position of the robot is preferentially used as a searching starting point of the neighborhood grid, and the effectiveness and the order of searching the neighborhood grid in multiple directions with the current position of the robot as the center are improved.

Further, the step 3 specifically includes: repeating the steps 31 and 32 until the length of the line segment between the current position of the robot and the newly screened known grid is greater than the diameter of the robot body; before re-executing the step 31, updating the current search position of the robot by using the grid which is closest to the current search position of the robot and is not repeatedly searched and is screened out by the step 31 which is executed last time; wherein, when detecting that the grid information of the grid screened in the step 31 does not appear in the second storage space, the grid participating in the detection is a grid which is not searched repeatedly; when it is detected that the grid information of the grid screened in the step 31 appears in the second storage space, the grid participating in the detection is a grid that is repeatedly searched.

According to the technical scheme, a new grid (a grid which is not repeatedly searched) is searched in an eight-neighborhood with the current searching position of the robot as the center, the current searching position of the robot is updated, a searchable area consisting of grids with shortest path characteristics is searched by repeatedly executing the steps 31 and 32, meanwhile, the reachable distance information of the robot is expanded to serve as a judging condition for stopping searching an unknown area until a known grid in a preset known grid area which is unreachable by the robot is obtained, and therefore the communication relation between the current position of the robot and the preset known grid area is rapidly identified in a larger area.

Further, in the step 3, the method further includes: repeating the steps 31 and 32 until the last searched known grid does not meet the second area traffic condition, and determining that the searching of all grids within the farthest searchable distance of the robot is finished; the furthest distance which the robot can search is determined by the size of the movement area in which the robot is positioned or the detectable distance of a sensor of the robot. In the technical scheme, in the process of repeatedly executing the steps 31 and 32, the condition that all grid searches in the furthest area which can be searched by the robot are finished is established.

Further, in the process of repeatedly executing the step 31 and the step 32, the known grid closest to the current search position of the robot screened in the step 31 and the current search position of the robot belong to the same connected domain, and the unknown grid closest to the current search position of the robot screened in the step 31 and the current search position of the robot do not belong to the same connected domain; when the latest searched known grid meets the second area passing condition, the searched connected domain is not communicated with the preset known grid area, so that the current position of the robot is located in an island area relative to the preset known grid area. Thereby gathering discrete map area information for the robot.

A chip storing the program codes corresponding to the region judgment method. Compared with the prior art, the area with the communication relation with the current position of the robot is efficiently determined by utilizing the shortest searching path distance, and the calculation load is saved.

A robot is provided with the chip. The path planning capability of the robot in searching for unknown environments is enhanced.

Further, the robot is equipped with visual sensors for detecting unknown environmental areas to construct a map and marking known grids on the map constructed in real time. Error accumulation of robot repositioning is reduced.

Drawings

Fig. 1 is a flow chart of a method for connectivity-based region determination in accordance with an embodiment of the present invention.

Detailed Description

The following describes the embodiments of the present application further with reference to the drawings. It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the application. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of exemplary embodiments according to the present application. As used herein, the singular is also intended to include the plural unless the context clearly indicates otherwise, and furthermore, it is to be understood that the terms "comprises" and/or "comprising" when used in this specification are taken to specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof.

In this embodiment, after the robot is started, or after the robot is triggered to reposition, after the repositioning is successful, or in the process of real-time navigation positioning, the robot marks an unobstructed grid or an obstacle grid near the starting position to construct a local map, specifically, the grids in the area taking the current position of the robot as the center and taking the preset detection length as the radius are marked as known grids; the preset detection length is smaller than or equal to the diameter of the robot body. Known grids include unobstructed grids and obstacle grids. As will be appreciated by those skilled in the art: the local map is marked with environmental information around the current position of the robot, the environmental information comprising grids within the map area constructed by the robot, the grids comprising three states marked free, occupied (occupied) and unknown (unknown); the grid in the idle state refers to a grid which is not occupied by an obstacle, is a grid position point which can be reached by a robot, is the barrier-free grid, and can form an unoccupied area; the grid in the occupied state refers to a grid occupied by an obstacle, and is the obstacle grid, so that an occupied area can be formed; the unknown grid is a grid area with unclear concrete conditions in the process of constructing a map by the robot, and the position points of the unknown grid are often blocked by obstacles, so that the unknown area can be formed.

It should be noted that, taking a sweeping robot as an example, a local probability grid may be established based on a single-line laser radar, or a local grid map may be established based on a vision sensor. And the global map is a map of the whole room drawn by the way of walking and recording in the room, and comprises occupied areas, unoccupied areas and unknown areas, wherein the occupied areas and the unoccupied areas can be attributed to the cleaned areas.

The embodiment of the invention discloses a region judging method based on connectivity, which comprises the following steps:

Step 1, searching a connected domain by searching the nearest known grid in the neighborhood until the latest searched known grid meets a first region passing condition, and determining that the current position of the robot is communicated with a preset known grid region, wherein the local map constructed at the current position of the robot is not overlapped with the preset known grid region; in the step 1, the robot moves in the motion area and traverses the generated local map, the local map comprises the current position of the robot, the current position of the robot is used as a search center to search a connected domain in eight neighborhoods, when the searched position of the search center is replaced, the neighborhood search is continuously performed by using a new search center to realize the search of all the known grids in the 360-degree direction and the neighborhood thereof, the connected domain search is stopped until the latest searched known grid meets the first area passing condition, and the current position of the robot is confirmed to be communicated with the preset known grid area, namely, the local map constructed at the current position of the robot is adjacently communicated with the preset known grid area, or the local map constructed at the current position of the robot is positioned in the coverage range of the preset known grid area and the two areas are overlapped together.

And2, in the process of executing the step 1, if the searching of all the known grids within the longest distance which can be reached by the robot is completed through the connected domain searching in the step 1, the step 3 is still carried out after the fact that the latest searched known grids still do not meet the first area passing condition is judged. Step 2 traverses the known grids within the local map constructed by the robot at the current position, but is insufficient to confirm that no known grids exist outside the constructed local map, because step 1 does not perform connected domain search for the unknown grids and their corresponding neighbors within the local map. The search determination operations of step 1 to step 2 are not comprehensive enough, so it is necessary to proceed to step 3 to continue the new connected domain search.

Step 3, searching a connected domain by searching the nearest grid in the neighborhood until judging that the latest searched known grid meets a second area passing condition, and determining that the current position of the robot is not connected with a preset known grid area; in the step 3, the current position of the robot is used as a search center to search the connected domain in the eight neighborhood regions, grid marking is performed at the same time, after the searched position of the search center is replaced, the neighborhood search is continuously performed by using a new search center to realize the search of all grids and the neighborhood thereof in the 360-degree direction, the search is stopped until the latest searched known grids meet the second region passing condition, namely, the connected domain search is stopped, and the fact that the current position of the robot is not connected with the preset known grid region is confirmed, namely, the local map constructed at the current position of the robot is positioned outside the preset known grid region and is not adjacent to the preset known grid region is confirmed.

Step 4, in the process of executing the step 3, after completing searching of all grids within the farthest searchable distance of the robot through the connected domain searching in the step 3, if the latest searched known grid does not meet the second area passing condition, determining that the current position of the robot is communicated with a preset known grid area, wherein the local map constructed at the current position of the robot overlaps with the preset known grid area; in step 4, traversing the grids in the range of the local map constructed by the robot at the current position, and confirming that no known grids exist outside the constructed local map, or considering that the constructed local map is overlapped with the preset known grid area, so that the searching range from step 3 to step 4 is more comprehensive.

Wherein the preset known grid region is a map region constructed and stored in the same motion region by the robot before the region determination method is performed. The embodiment may be a known map area and a traversed area which the robot reaches in advance, but the robot is forced to move out of the traversed area, and after being moved to the current position of the robot, the robot starts triggering repositioning, grid information of the current position of the robot can be determined, and a circular area with the radius of the preset detection length constructed at the current position of the robot is determined, wherein the coverage range of the circular area comprises a circle, a circle and a known grid area between the current position of the robot.

Compared with the prior art, the method comprises the steps of controlling the robot to conduct connected domain searching on the known grids of the neighborhood from the view of the accessibility of the robot, identifying connectivity in the known grid areas from the near to the far in a connected domain searching mode, and identifying connectivity in all types of grid areas from the near to the far in a connected mode, wherein the method comprises the steps of enabling a local map constructed at the current position of the robot to be communicated with the known map areas adjacently, enabling the local map constructed at the current position of the robot to overlap with the known map areas, enabling the local map constructed at the current position of the robot to be not communicated with the known map areas mutually, and comprehensively judging whether the current position of the robot is communicated with the known map areas at corresponding distances or not, and further judging whether the current position of the robot is located in the known map areas.

As an embodiment, as shown in fig. 1, the area determining method specifically includes:

Step S1, screening a grid closest to the current searching position of the robot from the neighbor grids of the current searching position of the robot in a first storage space which is created in advance, and determining the screened grid as: the aforementioned step 1 is performed by newly searching the known grid in the process of the connected domain search performed in the manner of neighborhood searching the nearest known grid. And then proceeds to step S2. It should be noted that, the first storage space created in advance stores a known neighborhood grid of the current search position of the robot, and the known neighborhood grid of the current search position of the robot is a known grid in the neighborhood grids of the current search position of the robot; in this step S1, the closest grid to the current search position of the robot is the smallest straight line distance from the current search position of the robot, and the straight line distances of at least the other neighbor grids with respect to the current search position of the robot are small.

Specifically, in step S1, the current search position of the robot is taken as a search starting point, the adjacent positions corresponding to the current search position of the robot all belong to the same connected domain with the current search position of the robot, namely eight-neighborhood grids, then one known grid closest to the current search position of the robot is selected from the eight-neighborhood grids, and is marked as an unobstructed grid or an obstacle grid closest to the current search position of the robot, if more than two known grids closest to the current search position exist, one of the known grids is randomly selected as the latest searched known grid, and the remaining known grids closest to the current search position of the robot are configured to be non-traversed, so that the subsequent search of all the known grids adjacent to the current search position of the robot is facilitated. In general, the adjacent positions above, below, left, and right of the current search position are all nearest to the current search position of the robot.

Step S2, updating the searching radius of the robot by the length of a line segment between the current position of the robot and the grid screened in the step S1 so as to describe the current reachable (directly reachable) distance of the robot; meanwhile, the grid information of the current searching position of the robot is stored in a second storage space which is created in advance, so that the grid position searched by the robot is stored in the second storage space, namely the grid information configured as the next searching starting point, preferably, the grid information of the current searching position is also stored in the second storage space, and the grid information is used for distinguishing the searched traversing grid position on the map area; meanwhile, grid information of the known grids in the neighborhood grids of the grids screened in the step S1 is stored in a first storage space created in advance and used for storing the grid information as a target grid to be searched, and preferably, if more than two known grids are equal in distance from the current searching position of the robot and are closest to the current searching position of the robot, the first storage space is further used for storing: in the neighbor grids of the current searching position of the robot, a plurality of known grids closest to the current searching position of the robot are selected except the grids selected in the step S1; and enabling the first storage space to only store grid information corresponding to barrier-free grids and/or barrier grids in the neighborhood of the current position of the robot. And then proceeds to step S3.

According to the embodiment, the step S1 and the step S2 are executed, the known grids are searched in the eight neighborhood centering on the current searching position of the robot, the known grids with the shortest path characteristics are searched to serve as target grids to be searched, the reachable distance information of the robot is expanded, meanwhile, the searched known grids are stored to distinguish the searched area and the unsearched area of the robot, the connected area formed by the connected known grids is quickly searched in the local area, and whether the current position of the robot reaches the preset known grid area is judged in an accelerating mode.

And step S3, judging whether the searching radius of the robot updated in the step S2 is larger than the diameter of the body of the robot, if so, entering the step S4, otherwise, entering the step S5. And step S4 is carried out when the latest searched known grids meet the first area passing condition, otherwise, after determining whether all the known grids in the constructed local map area are traversed, the step S1 and the step S2 are repeatedly executed. The connected domain search is implemented by searching the nearest known grid in the neighborhood.

Step S5, judging whether the first storage space created in advance is empty, if yes, stopping executing the steps S1 to S5, only searching the known grids when stopping executing the local map range, and then entering step S6; otherwise, returning to the step S1 to start to repeatedly execute the step S1 and the step S2, namely searching the map to search for the next connected domain formed by the adjacent known grids in a mode of continuously adopting the connected domain searching of the eight adjacent domains. Specifically, before step S5 is returned to execute step S1, the last executed grid which is screened out by step S1 and is closest to the current search position of the robot and is not repeatedly searched updates the current search position of the robot; when detecting that the grid information of the grids screened in the step S1 does not appear in the second storage space, the grid participating in the detection is a grid which is not repeatedly searched; when it is detected that the grid information of the grid screened in the step S1 has appeared in the second storage space, the grid participating in the detection is a grid that is repeatedly searched.

Step S4, determining that the current position of the robot is communicated with a preset known grid area, wherein the local map constructed by the robot at the current position of the robot is not overlapped with the preset known grid area, namely, the local map area (configured by the known grids) of the current position of the robot is adjacent to the preset known grid area, or the local map area (configured by the relatively small area range of the known grids) of the current position of the robot is located in the coverage area of the preset known grid area (relatively large area range), so that the robot can conveniently return to a target point (normal working position before repositioning) of the preset known grid area after repositioning, and simultaneously finishing executing the area judging method. In this embodiment, a new known grid (a known grid that is not repeatedly searched) is searched in an eight neighborhood around the current search position of the robot, and the current search position of the robot is updated, by repeatedly executing the step S1 and the step S2 to update the current search position of the robot, a reachable area formed by the communication of the known grids with the shortest path feature is searched, and the reachable distance information of the robot is expanded one by one of the known grids, until the first area passing condition is satisfied, all the known grids in the farthest area reachable by the robot are obtained, and the communication relationship between the current position of the robot and the preset known grid area is rapidly identified in the near-distance area. It should be noted that, in the process of repeatedly executing the step S1 and the step S2, the known grid closest to the current search position of the robot screened in the step S1 and the current search position of the robot belong to the same connected domain, and when the newly searched known grid meets the first area passing condition, the current position of the robot is connected with the preset known grid area through the connected domain, so that the current position of the robot, the connected domain and the preset known grid area become the connected domain supporting the robot to plan a feasible path.

It should be noted that, when the pre-created first storage space is determined to be empty, that is, when grid information of the known grids stored in the first storage space has been all read out to participate in the connected domain search, specifically, when the pre-created first storage space is empty and the connected domain search is completed by using the connected domain search in step 1, after it is determined that all the known grids within the farthest distance reachable by the robot have not been stored in the farthest distance reachable by the robot as the known grids to be searched for storing in the first storage space, and at the same time, it is determined that all the known grids screened from the first storage space are stored as searched target grids; wherein, the furthest distance that the robot can reach is the maximum search radius obtained by updating in the process of executing the steps S1 to S5. In the present embodiment, in the process of repeatedly executing the steps S1 and S2, the condition that all the known grid searches in the furthest region reachable by the robot are finished is established.

On the basis of the foregoing embodiment, before executing the step S1, the method further includes: after the first storage space and the second storage space are created, initializing the first storage space and the second storage space respectively; then, grid information of the current position of the robot is stored in the first storage space, and the current position of the robot is configured as a current searching position of the robot; screening grids closest to the current searching position of the robot from the first storage space, wherein the longest distance which can be reached by the robot is the largest searching radius obtained by updating in the process of executing the step 12, and the searching radius of the robot is updated to be 0 at the moment; then, storing the grid information of the current position of the robot into the second storage space, and storing the grid information of the known grids in the neighborhood grids of the current position of the robot into the first storage space, so that the first storage space only stores detected barrier-free grids and/or detected barrier grids in the neighborhood of the current position of the robot; the first storage space created in advance is a memory space supporting grid information caching according to a first-in first-out sequence. When the first storage space is set as the priority queue, the step S5 determines that the current position node of the robot may be dequeued from the priority queue when the first storage space is empty. In the embodiment, the current position of the robot is preferentially used as the searching starting point of the connected domain, so that the effectiveness and the order of searching adjacent connected domains are improved. The second storage space is preferably arranged in a list structure.

It is noted that, the first storage space created in advance in step S5 is empty, and when it is determined that the latest searched known grid does not meet the first area traffic condition, step S6 is entered. In step S6, the first storage space is emptied to avoid the influence of the target grid to be searched stored in the foregoing embodiment, and the second storage space is emptied to avoid the influence of the searched target grid stored in the foregoing embodiment, so that the initialization of the first storage space and the initialization of the second storage space are completed, and then step S7 is performed.

In this embodiment, if the length of the line segment between the last searched known grid and the current position of the robot is smaller than or equal to the body diameter of the robot, it indicates that no new known grid exists in the neighborhood of the last searched known grid, and indicates that no passable path is searched for in the neighborhood of the last searched known grid. When the robot is mapped and positioned at a new position, if only unknown grids can be searched from the surrounding neighborhood of the current searching position, the robot has searched all the known grids in the area within one body diameter from the current position of the robot, and the rest is the unknown grids concentrated outside one body diameter from the current position of the robot, so that the robot can traverse the map area built by the robot. Since the robot needs to execute step 3 to further search all the mark type grids in the neighborhood and guide and judge whether the preset known grid area is searched or not on the basis of the mark type grids, the grid information stored by searching only the known grids in the previous step is emptied so as to avoid influencing the searching range due to repeated searching.

Step S7, in the first storage space created in advance, one grid closest to the current searching position of the robot is screened out from neighbor grids of the current searching position of the robot, but the screened grid is not necessarily: the aforementioned step 3 is to newly search for a known grid in the course of the connected domain search performed in such a manner that the nearest grid is searched for in the neighborhood. And then proceeds to step S8. The first storage space created in advance stores a neighborhood grid of the current search position of the robot, wherein the neighborhood grid of the current search position of the robot comprises a known grid and an unknown grid in the neighborhood grids of the current search position of the robot. Specifically, in step S7, the current search position of the robot is taken as the search starting point, the adjacent positions corresponding to the current search position of the robot all belong to the same connected domain with the current search position of the robot, namely eight neighbor grids, then one grid closest to the current search position of the robot is selected from the eight neighbor grids, if more than two grids closest to the current search position of the robot exist, one of the grids closest to the current search position is randomly selected, the remaining grids closest to the current search position are configured as non-traversed and serve as candidate search target points, and a new connected domain search using the newly searched grids as the search starting point is also reserved.

Step S8, storing the grid information of the current searching position of the robot into a pre-created second storage space so that the second storage space stores the searched grid position of the robot, namely the grid information configured as the next searching starting point, and the grid information is used for distinguishing the searched traversing grid position on the map area; meanwhile, grid information of the neighborhood grids of the grids screened in the step S7 is stored in a first storage space which is created in advance to be stored as a target grid to be searched, so that the first storage space stores barrier-free grids, unknown grids and/or barrier grids in the neighborhood of the current position of the robot; preferably, if there are more than two grids closest to the current search position of the robot, the first storage space is further used to store: among the neighbor grids of the current search position of the robot, the grids closest to the current search position of the robot are selected in step S7. When the grid screened in the step S7 is a known grid, determining the grid screened in the step S7 as the known grid which is searched most recently in the step 3 or the step 4, updating the searching radius of the robot according to the length of a line segment between the current position of the robot and the known grid which is searched most recently (screened most recently), and searching a map area according to the ray with the searching radius as the searching length so as to describe the current searchable distance of the robot, but not necessarily the reachable distance of the robot because the unknown grid can be covered. It is noted that the grid selected in step S7 is not a grid that is repeatedly selected.

With respect to steps S1 to S2 in the foregoing embodiments, steps S7 to S8 determine that the connected domain searching method of searching for a new known grid in the eight neighborhood centered on the current searching position of the robot cannot find a preset known grid area connected to the current position of the robot, and then find a grid with the shortest path characteristic in the eight neighborhood centered on the current searching position of the robot as a target grid to be searched and expand the reachable distance information of the robot, so as to quickly search for the preset known grid area which is not connected to the preset known grid area and the preset known grid area which is connected to the searching small area in all directions, and perform the grid searching of the larger area (the known grids which are not limited by the possible discrete distribution) without being limited by the known grids and the unknown grids in the process of performing steps S7 to S8.

And step S9, judging whether the searching radius of the robot updated in the step S8 is larger than the diameter of the body of the robot, if so, entering the step S11, otherwise, entering the step S10.

And step S10, judging whether the first storage space is empty, if yes, stopping executing the steps S6 to S10, stopping searching grids in the local map range, and then entering the step S12, otherwise, returning to the step S7 to start repeatedly executing the steps S7 and S8, namely searching the map to search the next adjacent connected domain in a mode of continuously adopting the eight-neighborhood connected domain searching. Specifically, before step S10 returns to execute step S7, the last executed grid that is screened out by step S7 and is closest to the current search position of the robot and is not repeatedly searched updates the current search position of the robot; when detecting that the grid information of the grids screened in the step S7 does not appear in the second storage space, the grid participating in the detection is a grid which is not repeatedly searched; when it is detected that the grid information of the grid screened in the step S7 has appeared in the second storage space, the grid participating in the detection is a grid that is repeatedly searched.

Step S11, determining that the current position of the robot is not communicated with a preset known grid area, namely that the local map area (configured by the known grids) where the current position of the robot is located is not communicated with the preset known grid area. It should be noted that, the known grid closest to the current search position of the robot screened in the step S8 belongs to the same connected domain as the current search position of the robot, and the unknown grid closest to the current search position of the robot screened in the step S8 does not belong to the same connected domain as the current search position of the robot; when the latest searched known grid meets the second area passing condition, the searched connected domain is not communicated with the preset known grid area, and the current position of the robot is determined to be located in an island area relative to the preset known grid area. Thus gathering discrete map area information for the robot but increasing the difficulty of navigating back to a target point of the preset known grid area after repositioning of the robot.

Step S12, determining that the current position of the robot is communicated with a preset known grid area, wherein the local map constructed by the robot at the current position of the robot is overlapped with the preset known grid area. Specifically, when step S10 determines that the first storage space is empty, that is, when grid information of grids (all types of grids) stored in the first storage space has been read out to participate in the connected domain search, specifically, when the previously created first storage space is empty while the last searched known grid remains unsatisfied with the second area traffic condition, after searching of all grids within the farthest distance that the robot can explore has been completed using the connected domain search described in step 3, it is determined that after searching of all grids within the farthest distance that the robot can search is completed, the updated search radius of the robot remains smaller than the body diameter of the robot, that is, the known grids searched within the farthest distance that the robot can search are all within the coverage area of the local map constructed at the current position of the robot, and then it is determined that the local map constructed at the current position of the robot overlaps with the preset known grid area. The furthest distance which the robot can search is determined by the size of the movement area in which the robot is positioned or the detectable distance of a sensor of the robot. When the detectable distance of the sensor of the robot is greater than the maximum length of the movement region where the sensor is located, the furthest distance the robot can search for is equal to the maximum length of the movement region where the sensor is located; when the detectable distance of the sensor of the robot is less than or equal to the maximum length of the movement zone in which it is located, the furthest distance the robot can search is equal to the detectable distance of the sensor of the robot.

Step S10 also determines that there is no known grid for storing as a target grid to be searched within the furthest distance that the robot can search to store in the first storage space when it is determined that the first storage space is empty, and determines that all grids screened from the first storage space are stored as searched target grids. In the present embodiment, in the process of repeatedly performing the steps S7 and S8, the condition that all the known grid searches in the farthest area that the robot can search are ended is established.

In summary, in the embodiment of the present invention, a new grid (a grid that is not repeatedly searched) is searched in an eight-neighborhood with the current search position of the robot as the center, and the current search position of the robot is updated, by repeatedly executing the steps S7 and S8, a searchable area composed of grids with shortest path features is searched, and meanwhile, the reachable distance information of the robot is expanded to serve as a judging condition for stopping searching an unknown area until a known grid in a preset known grid area that is unreachable by the robot is obtained, so that the communication relationship between the current position of the robot and the preset known grid area is rapidly identified in a larger area.

On the basis of the foregoing steps S7 to S12, after the first storage space and the second storage space are emptied, before executing the step S7, the method further includes: firstly, storing grid information of the current position of the robot into the first storage space, and configuring the current position of the robot as the current searching position of the robot; screening grids closest to the current searching position of the robot from the first storage space, enabling the current position of the robot to be the grid closest to the current searching position of the robot, and enabling the searching radius of the robot to be updated to be 0 when the known grids are screened; and then storing the grid information of the current position of the robot into the second storage space, and storing the grid information of the neighborhood grid of the current position of the robot into the first storage space, so that the first storage space stores the detected barrier-free grid, the unknown grid and/or the detected barrier grid in the neighborhood of the current position of the robot. According to the technical scheme, the current position of the robot is preferentially used as a searching starting point of the neighborhood grid, and the effectiveness and the order of searching the neighborhood grid in multiple directions with the current position of the robot as the center are improved.

A chip storing program codes corresponding to the region determination method of the foregoing embodiment. Compared with the prior art, the method and the device have the advantages that the area with the communication relation with the current position of the robot is efficiently determined by utilizing the shortest searching path distance based on the robot assembled by the chip, and the calculation load is saved.

A robot is provided with the chip. The path planning capability of the robot in searching for unknown environments is enhanced. Preferably, the robot is equipped with visual sensors for detecting unknown areas of the environment to build a map and marking known grids on the map built in real time. Error accumulation of robot repositioning is reduced. When the robot is a sweeping robot, the sweeping robot rotates a circle at the current position, the furthest distance seen by the camera is the furthest distance reachable by the sweeping robot, the circle determined by taking the furthest distance reachable as the radius and the field of view area in the circle are determined as reachable areas of the sweeping robot, and the sweeping robot can be used for updating a local map constructed in time and updating searched area information, but does not necessarily represent the current searchable area of the robot, and the current searchable area is mainly used for evaluating whether the navigable navigation points exist in all directions.

It will be appreciated by those skilled in the art that embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention in any way, and any person skilled in the art may make modifications or alterations to the above disclosed technical content to the equivalent embodiments. However, any simple modification, equivalent variation and variation of the above embodiments according to the technical substance of the present invention still fall within the protection scope of the technical solution of the present invention.

Claims (10)

1. A connectivity-based region judgment method, the region judgment method comprising:

step 1, searching a connected domain by searching the nearest known grid in the neighborhood until judging that the latest searched known grid meets a first area passing condition, and determining that the current position of the robot is communicated with a preset known grid area, wherein a local map constructed at the current position of the robot is not overlapped with the preset known grid area;

Step 2, after searching all the known grids within the longest distance which can be reached by the robot through the connected domain search in the step 1, if the latest searched known grids are judged not to meet the first area passing condition, entering the step 3;

Step 3, searching a connected domain by searching the nearest grid in the neighborhood until judging that the latest searched known grid meets a second area passing condition, and determining that the current position of the robot is not connected with a preset known grid area;

Step 4, after searching all grids within the farthest distance which can be searched by the robot through the connected domain searching in the step 3, if the latest searched known grid does not meet the second area passing condition, determining that the current position of the robot is communicated with a preset known grid area, wherein a local map constructed at the current position of the robot overlaps the preset known grid area;

The method comprises the steps that a known grid area is preset, and before the area judging method is executed, a robot builds and stores a map area in the same motion area;

The robot builds a local map at its current position, which is specifically: the grids in the area with the current position of the robot as a circle center and the preset detection length as a radius are marked as known grids;

The preset detection length is smaller than or equal to the diameter of the robot body;

wherein the known grid includes an unobstructed grid and an obstacle grid;

the condition that the first area passing condition is met means that the length of a line segment between the current position of the robot and the known grid newly searched in the step 1 is larger than the diameter of a body of the robot;

The condition of the second area passing is that the length of a line segment between the current position of the robot and the known grid which is searched out in the step 3 is larger than the diameter of the robot body;

In the step 1, the method step of searching the connected domain by searching the nearest known grid in the neighborhood specifically includes:

Step 11, screening a grid closest to the current searching position of the robot from a first storage space created in advance, determining the screened grid as the latest searched known grid in the step 1 or the step 2, and then entering the step 12; wherein the pre-created first storage space stores a known neighborhood grid of the current search position of the robot, the known neighborhood grid of the current search position of the robot being a known grid in the neighborhood grids of the current search position of the robot;

Step 12, storing grid information of the current searching position of the robot into a pre-created second storage space to be stored as a searched target grid; in the neighborhood grids of the grids screened in the step 11, storing grid information of the known grids into a first storage space created in advance so as to be stored as target grids to be searched; meanwhile, updating the searching radius of the robot to be the length of a line segment between the current position of the robot and the grid screened in the step S11;

The neighborhood grids of the current searching position of the robot are corresponding to 8 adjacent grids on a grid map built by the robot in real time by taking the current searching position of the robot as a center, and the known grids in the 8 grids are known neighborhood grids; the grids screened in the step 11 do not belong to the grids screened repeatedly;

In the step 1, further includes:

Repeatedly executing the step 11 and the step 12 until all the known grids in the longest distance reachable by the robot are searched when the latest searched known grids keep not meeting the first area passing condition and the pre-created first storage space is empty;

wherein the furthest distance reachable by the robot is the maximum said search radius updated and obtained during execution of step 12;

in the step 3, the method step of searching the connected domain by searching the nearest grid in the neighborhood specifically includes:

Step 31, screening a grid closest to the current searching position of the robot from neighbor grids of the current searching position of the robot in a first storage space which is created in advance, and then entering step 32;

Step 32, storing the grid information of the current searching position of the robot into a pre-created second storage space to be stored as a searched target grid, and storing the grid information of the neighborhood grid of the grid screened in step 31 into a pre-created first storage space to be stored as a target grid to be searched, so that the first storage space stores barrier-free grids, unknown grids and/or barrier grids in the neighborhood of the current position of the robot; when the grid screened in the step 31 is a known grid, determining the grid screened in the step 31 as the latest searched known grid in the step 3 or the step 4;

The neighborhood grids of the current searching position of the robot take the current searching position of the robot as a center, 8 grids which are adjacent to each other are corresponding to the grid map which is built immediately by the robot, and the known grids in the 8 grids and the current searching position of the robot form a searched connected domain respectively; the grid screened in step 31 is not a grid that is repeatedly screened.

2. The area determination method according to claim 1, further comprising, before performing the step 11: after the first storage space is created for storage, grid information of the current position of the robot is stored in the first storage space, and the current position of the robot is configured as the current searching position of the robot; screening grids closest to the current searching position of the robot from the first storage space, so that the current position of the robot is screened out from the first storage space and becomes the grids closest to the current searching position of the robot; then, storing the grid information of the current position of the robot into the second storage space, and storing the grid information of the known grids in the neighborhood grids of the current position of the robot into the first storage space;

the first storage space created in advance is a memory space supporting grid information caching according to a first-in first-out sequence.

3. The area determining method according to claim 2, wherein the step 1 specifically includes: repeating the steps 11 and 12 until the length of the line segment between the current position of the robot and the known grid searched by the step 11 is larger than the diameter of the robot body;

before re-executing the step 11, updating the current search position of the robot by using the grid which is closest to the current search position of the robot and is not repeatedly searched and is screened out in the step 11;

When detecting that the grid information of the grid screened in the step 11 does not appear in the second storage space, the grid participating in the detection is a grid which is not searched repeatedly; when detecting that the grid information of the grid screened in the step 11 appears in the second storage space, the grid participating in the detection is a grid which is repeatedly searched.

4. The area determination method according to claim 1, wherein the first storage space and the second storage space are emptied before starting to execute step 3 after ending to execute step 2.

5. The area determination method according to claim 4, further comprising, after the first storage space and the second storage space are emptied, before performing the step 31: firstly, storing grid information of the current position of the robot into the first storage space, and configuring the current position of the robot as the current searching position of the robot; screening grids closest to the current searching position of the robot from the first storage space, so that the current position of the robot becomes the grid closest to the current searching position of the robot; and then storing the grid information of the current position of the robot into the second storage space, and storing all the grid information of the neighborhood grids of the current position of the robot into the first storage space.

6. The method according to claim 5, wherein the step 3 specifically includes: repeating the steps 31 and 32 until the length of the line segment between the current position of the robot and the newly screened known grid is greater than the diameter of the robot body;

before re-executing the step 31, updating the current search position of the robot by using the grid which is closest to the current search position of the robot and is not repeatedly searched and is screened out by the step 31 which is executed last time;

Wherein, when detecting that the grid information of the grid screened in the step 31 does not appear in the second storage space, the grid participating in the detection is a grid which is not searched repeatedly; when it is detected that the grid information of the grid screened in the step 31 appears in the second storage space, the grid participating in the detection is a grid that is repeatedly searched.

7. The area determination method according to claim 6, further comprising, in the step 3:

Repeating the steps 31 and 32 until the last searched known grid does not meet the second area traffic condition, and determining that the searching of all grids within the farthest searchable distance of the robot is finished;

the furthest distance which the robot can search is determined by the size of the movement area in which the robot is positioned or the detectable distance of a sensor of the robot.

8. A chip configured to execute the program code corresponding to the area determination method according to any one of claims 1 to 7.

9. A robot incorporating the chip of claim 8.

10. The robot of claim 9, wherein the robot is equipped with visual sensors for detecting unknown areas of the environment to construct a map and marking known grids on the map constructed in real time.