CN111596662A

CN111596662A - Method for judging one circle along global working area, chip and visual robot

Info

Publication number: CN111596662A
Application number: CN202010456792.9A
Authority: CN
Inventors: 李明; 赖钦伟; 李永勇
Original assignee: Zhuhai Amicro Semiconductor Co Ltd
Current assignee: Zhuhai Amicro Semiconductor Co Ltd
Priority date: 2020-05-26
Filing date: 2020-05-26
Publication date: 2020-08-28
Anticipated expiration: 2040-05-26
Also published as: CN111596662B

Abstract

The invention discloses a method for judging one circle along a global working area, a chip and a visual robot, wherein the method comprises the following steps: controlling the cleaning robot to clean and traverse the global working area according to a preset cleaning mode and constructing a global grid map; and then controlling the cleaning robot to start to walk edgewise from a preset edgewise starting point in the global working area, and when the ratio of the area of a map area framed by the edgewise walking path of the cleaning robot in each global coordinate axis direction of the global grid map to the area of the map area traversed by the cleaning robot meets a preset coverage rate condition and the relative position relationship between the grid coordinate point of the current position of the cleaning robot on the global grid map and the grid coordinate point of the preset edgewise starting point on the global grid map meets a superposition error condition, determining that the cleaning robot completely walks for one circle along the global working area. The misjudgment that the robot walks for a circle completely along the global working area due to a complex and changeable cleaning scene is overcome.

Description

Method for judging one circle along global working area, chip and visual robot

Technical Field

The invention relates to the technical field of edgewise walking of sweeping robots, in particular to a method for judging a circle of a cleaning robot along a global working area based on a global grid map.

Background

Sweeping robots often sweep around corners of a room by sweeping around the edges. Due to the fact that the layout of rooms of different families and the furniture in the rooms are various, cleaning scenes of the robot are complex and changeable (such as various dynamic obstacles and the opening and closing states of doors) easily, and a map constructed by a visual sensor of the robot has drift errors along with the time, real-time positioning of the robot on the position of the robot is affected according to the constructed map, and the fact that how to judge whether the robot completely follows the indoor environment for a circle is always a difficulty which troubles the robot for cleaning the floor.

Disclosure of Invention

In order to solve the technical problem, the invention discloses a method for accurately judging a complete edge circle by depending on a global grid map, which comprises the following specific technical scheme:

a method for determining a turn along a global operating region, comprising: controlling the cleaning robot to clean and traverse the global working area according to a preset cleaning mode, and constructing a global grid map according to information recorded in the cleaning and traversing process; after the global working area is cleaned, controlling the cleaning robot to walk edgewise in the global working area from a preset edgewise starting point, and meanwhile calculating the area of a map area framed by an edgewise walking path of the cleaning robot in each global coordinate axis direction of the global grid map and the area of the map area traversed by the cleaning robot; the method comprises the following steps that the areas of all traversed map areas of a cleaning robot are calculated from the time when the cleaning robot sweeps and traverses a global working area according to a preset sweeping mode; when the ratio of the area of a map region framed by the edge walking path of the cleaning robot in each global coordinate axis direction of the global grid map to the area of the map region traversed by the cleaning robot meets a preset coverage condition, and the relative position relationship between the grid coordinate point of the current position of the cleaning robot on the global grid map and the grid coordinate point of the preset edge starting point on the global grid map meets a superposition error condition, the cleaning robot is determined to completely walk for one circle along the global working region.

Compared with the prior art, the technical scheme can utilize the judgment condition of the area framed on the global map by the edgewise walking path of the cleaning robot to measure the edgewise coverage of the robot in a complex and changeable cleaning scene, and simultaneously set the relative position relation between the current position of the cleaning robot and the preset edgewise starting point and the judgment condition of the optimized path to measure the position drift degree of the robot in the constructed global map.

Further, the preset coverage rate condition is that the ratio of the area of a map region framed by the edgewise walking path of the cleaning robot in the direction of the horizontal coordinate axis to the area of all map regions traversed by the cleaning robot is greater than the preset coverage rate, and the ratio of the area of the map region framed by the edgewise walking path of the cleaning robot in the direction of the vertical coordinate axis to the area of all map regions traversed by the cleaning robot is greater than the preset coverage rate; the global coordinate axis direction comprises a horizontal coordinate axis direction and a vertical coordinate axis direction; when the ratio of the area of a map region framed by the edgewise walking path of the cleaning robot in the horizontal coordinate axis direction to the area of all the traversed map regions of the cleaning robot is smaller than or equal to the preset coverage rate, or the ratio of the area of the map region framed by the edgewise walking path of the cleaning robot in the vertical coordinate axis direction to the area of all the traversed map regions of the cleaning robot is smaller than or equal to the preset coverage rate, determining that the cleaning robot does not completely walk for one circle along the global working region. According to the technical scheme, from the aspect of coverage rate of robot walking, the influence of the area of a map area framed by the edgewise walking path of the cleaning robot in the direction of a vertical coordinate axis or a horizontal coordinate axis on complete edgewise circle judgment is fully considered, so that the ratio of the area of the map area framed by the edgewise walking path of the cleaning robot to the area of all traversed map areas of the cleaning robot is used as the judgment amount of the coverage rate.

Further, before the cleaning robot cleans and traverses the global working area according to a preset cleaning mode, the method further comprises the following steps: setting the side length of a map traversal block according to the size of the global grid map, and determining the coverage quantity of the map traversal blocks in all global coordinate axis directions of the global grid map by calculating the ratio relation between the size of the global grid map and the side length of the map traversal block on the basis of the side length of the map traversal block; then calculating mapping coordinates of the map traversal blocks by combining the side lengths and the number of the map traversal blocks, and laying the map traversal blocks to each row and each column of the global grid map; the map traversal blocks of each row of the global grid map are arranged in the direction of the horizontal coordinate axis and the projections of the map traversal blocks in the direction of the vertical coordinate axis are overlapped, and the map traversal blocks of each column of the global grid map are arranged in the direction of the vertical coordinate axis and the projections of the map traversal blocks in the direction of the horizontal coordinate axis are overlapped; and each map traversal block is formed by combining grids of the global grid map according to the mapping coordinates of the map traversal block. According to the technical scheme, the global working area is regularly divided into the map traversal blocks, the map traversal blocks which are regularly arranged in rows and columns can reflect the environmental characteristics of the global working area, the method is suitable for processing the global grid maps with various scales, and the self-adaption degree of the algorithm is improved; meanwhile, the operation resources of the grid surface in the global map are saved, and the data processing speed is increased.

Further, when the cleaning robot traverses any grid in the map traversal block according to the preset cleaning mode, marking the corresponding map traversal block as a passed map traversal block; when the cleaning robot walks into the map traversal block along the edge, the map traversal block is marked to be the edge map traversal block and the map traversal block which has already been walked, so that the edge walking path is formed by the edge map traversal block on the global grid map, the cleaning path which has been traversed by the cleaning robot in the global working area is formed by the map traversal block which has already been walked, and compared with a grid marking mode, the map traversal block records a larger path area range, the number of the mark blocks used for marking the same path is reduced, the calculation force requirement and the storage space requirement on the cleaning robot are reduced, and the map building time is reduced.

Further, the calculating the area of the map area framed by the edgewise walking path of the cleaning robot in each global coordinate axis direction of the global grid map includes: calculating the area of a map area framed by the edgewise walking path of the cleaning robot in the vertical coordinate axis direction of the global grid map and calculating the area of a map area framed by the edgewise walking path of the cleaning robot in the horizontal coordinate axis direction of the global grid map; the method for calculating the area of the map area framed by the edgewise walking path of the cleaning robot in the horizontal coordinate axis direction of the global grid map comprises the following steps: judging whether the edgewise map traversal blocks exist in the map traversal blocks of each row of the global grid map, if so, counting the number of the map traversal blocks from the edgewise map traversal block at the lowest end to the edgewise map traversal block at the highest end in the corresponding row, and recording the number as the area of the edgewise walking path of the cleaning robot in the defined map area of the row; the map area framed by each row of the edgewise walking path of the cleaning robot comprises the bottommost edgewise map traversal block and the topmost edgewise map traversal block in the same row; when map traversal blocks of all rows of the global grid map are judged according to the steps, setting the sum of the areas of the map areas framed by the border walking path of the cleaning robot in each row as the area of the map area framed by the border walking path of the cleaning robot in the vertical coordinate axis direction of the global grid map; the method for calculating the area of the map area framed by the edgewise walking path of the cleaning robot in the horizontal coordinate axis direction of the global grid map comprises the following steps: judging whether the border map traversal blocks exist in each row of the global grid map, if so, counting the number of the map traversal blocks from the border map traversal block at the leftmost end to the border map traversal block at the rightmost end on the corresponding row, and recording the number as the area of the border walking path of the cleaning robot in the framed map area of the row; the map area framed by each row of the edgewise walking path of the cleaning robot comprises the edgewise map traversal block at the leftmost end and the edgewise map traversal block at the rightmost end of the same row; and when the map traversal blocks of all the rows of the global grid map are judged according to the steps, setting the sum of the areas of the map areas framed by the edge walking path of the cleaning robot in each row as the area of the map area framed by the edge walking path of the cleaning robot in the horizontal coordinate axis direction of the global grid map.

Compared with the prior art, in each row of map traversal blocks of the global grid map, the area of a map area framed by the edgewise walking path in the vertical coordinate axis direction of the global grid map is calculated by counting the number of the map traversal blocks included between the edgewise map traversal block at the lowest end and the edgewise map traversal block at the highest end; in each row of map traversal blocks of the global grid map, calculating the area of a map area framed by the edgewise walking path in the horizontal coordinate axis direction of the global grid map by counting the number of the map traversal blocks included between the edgewise map traversal block at the leftmost end and the edgewise map traversal block at the rightmost end; according to the technical scheme, the area of the map area framed by the edge walking path in each coordinate axis direction of the global coordinate system can completely represent the coverage area of the cleaning robot walking along the edge at present, and the use of the map traversal block also reduces the calculation amount of the grid area in the global map in the prior art.

Further, the relative position relationship between the current position of the cleaning robot and the preset edgewise starting point meets the superposition error condition, which includes: the distance between the grid coordinate point of the current position of the cleaning robot on the global grid map and the line segment of the preset edgewise starting point on the grid coordinate point of the global grid map meets the preset drifting threshold condition, and the optimal path searched between the current position of the cleaning robot and the preset edgewise starting point meets the preset coincident positioning condition. The cleaning robot can accurately judge whether to return to the preset edge starting point through one edge circle.

Further, the preset drift threshold condition is that the distance between the grid coordinate point of the current position of the cleaning robot on the global grid map and the line segment of the preset edge starting point on the grid coordinate point of the global grid map is smaller than a preset drift error threshold value; and when the connection line distance between the coordinate point of the current position of the cleaning robot on the global grid map and the coordinate point of the preset edge starting point on the global grid map is greater than or equal to a preset drift error threshold value, determining that the cleaning robot does not return to the preset edge starting point. According to the technical scheme, the distance between the current position of the cleaning robot and the coordinate connecting line of the preset edge starting point on the global grid map is used as a pre-judging condition for the robot to return to the preset edge starting point, and the influence of severe map drift on the return of the cleaning robot to the preset edge starting point is eliminated.

Further, the preset superposition positioning condition is that the number of grids contained in the optimal path searched between the current position of the cleaning robot and the preset edge starting point is less than the number of grids of the preset path; and on the premise that the connection distance between the grid coordinate point of the current position of the cleaning robot on the global grid map and the grid coordinate point of the preset edge starting point on the global grid map meets the preset drift threshold condition, if the number of grids contained in the optimal path searched between the current position of the cleaning robot and the preset edge starting point is greater than the number of grids in the preset path, determining that the cleaning robot does not return to the preset edge starting point. On the basis of the technical scheme, the optimal path length searched between the current position of the cleaning robot and the preset edge starting point is utilized to judge and determine the superposition positioning condition of the current position of the cleaning robot and the preset edge starting point, so that the robot is helped to select the shortest path to return to the preset edge starting point.

Further, the optimal path searched between the current position of the cleaning robot and the preset edgewise starting point is as follows: and according to the current position of the robot and the preset edge starting point, calculating a shortest path by using an A-x algorithm to serve as an optimal path for the robot to navigate back to the preset edge starting point. The positioning accuracy of the robot is improved.

A chip is internally provided with a control program, and the control program is used for controlling the cleaning robot and the judging method, so that the control program comprises part or all of the steps of the judging method.

The chip is arranged in the visual robot and is used for overcoming the influence of map drift in the process of executing the judgment method by the visual robot.

Drawings

Fig. 1 is a flowchart of a method for determining a circle along a global working area according to an embodiment of the present invention.

Fig. 2 is a schematic view of a working scene in which the cleaning robot completely follows an edge for one circle in the global working area and returns to a preset edge starting point a (ignoring the influence of the width of the wall).

Fig. 3 is a schematic diagram of a working scene in which the area framed in the X-axis direction by the border map traversal block (diagonal filling block) marked in the global working area by the cleaning robot does not meet the preset coverage condition.

Fig. 4 is a schematic diagram of a working scenario in which the length of a line between the current position of the cleaning robot and the preset edge starting point satisfies a preset drift threshold condition (ignoring the influence of the width of the wall).

Detailed Description

The technical solutions in the embodiments of the present invention will be described in detail below with reference to the accompanying drawings in the embodiments of the present invention. To further illustrate the various embodiments, the invention provides the accompanying drawings. The accompanying drawings, which are incorporated in and constitute a part of this disclosure, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the embodiments. Those skilled in the art will appreciate still other possible embodiments and advantages of the present invention with reference to these figures. Elements in the figures are not drawn to scale and like reference numerals are generally used to indicate like elements.

As shown in fig. 1, an embodiment of the present invention discloses a method for determining one turn along a global working area, including: step S101, controlling the cleaning robot to perform sweeping traversal on the global working area according to a preset sweeping manner, and constructing a global grid map according to information recorded in the sweeping traversal process, as shown in the working scene diagrams of fig. 2 and 4, the grid map areas corresponding to the room areas #1, #2, and #3 are all marked with a zigzag sweeping path, that is, the cleaning robot performs sweeping traversal on the global working area according to zigzag sweeping in this embodiment, so as to implement comprehensive coverage sweeping traversal on the global working area, and synchronously constructing the global grid map according to sweeping environment information recorded in the sweeping traversal process, and then entering step S102.

Step S102, after the cleaning robot finishes cleaning the global working area and marks related traversal information in the global grid map, controlling the cleaning robot to walk along the edge in the global working area from a preset edge starting point, meanwhile, calculating the area of a map area framed by the edge walking path of the cleaning robot in each global coordinate axis direction of the global grid map and the area of the map area traversed by the cleaning robot, and then entering step S103. As shown in fig. 2 to 4, the cleaning robot travels edgewise in the same global work area from a preset edgewise start point, and calculates the area of a map area framed by a dotted line in each global coordinate axis direction of the global grid map by the edgewise travel path of the cleaning robot and the area of a map area traversed by the cleaning robot, including the areas of areas marked by the dotted-lined map area and the zigzag path in room areas #1, #2, and # 3. The areas of all traversed map areas of the cleaning robot are calculated in an accumulated manner from the time when the cleaning robot sweeps the global working area in a preset sweeping manner, and also include the areas of the areas traversed by the edgewise walking of the cleaning robot, and actually are the sum of the areas of the map areas traversed by the cleaning robot in advance sweeping the global working area in the preset sweeping manner and the areas of the map areas covered by the current edgewise walking path of the cleaning robot.

The basic concept of the determination method described in step S103 to step S106 of fig. 1 is: when the ratio of the area of the map area framed by the edgewise walking path of the cleaning robot in each global coordinate axis direction of the global grid map to the area of the map area traversed by the cleaning robot meets the preset coverage condition and the relative position relationship between the current position of the cleaning robot and the preset edgewise starting point meets the coincidence error condition, it is determined that the cleaning robot completely walks for one circle along the global working area, that is, it is determined that the cleaning robot completely walks for one circle along the global working area shown in fig. 2. The embodiment of the invention comprehensively considers various factors such as influence of complex changeable environments such as a large number of static barriers such as walls, various dynamic barriers, opening and closing states of doors and the like existing in the working environment of the home service robot on continuous service of the home service robot across sub-working areas, measures the edge coverage of the robot in a complex changeable cleaning scene by utilizing the judgment condition of the area framed by the edge walking path of the cleaning robot on a global map, simultaneously sets the judgment condition of the relative grid position relation of the current position of the cleaning robot and the preset edge starting point to measure the position drift degree of the robot in the constructed global map, then overcomes the misjudgment of the robot on the complete walking of the robot along the global working area due to the complex changeable cleaning scene based on the two judgment conditions, realizes that the cleaning robot accurately judges whether the contour of the indoor environment completely follows one circle, the cleaning machine is better suitable for home environment and can continuously clean a plurality of sub-working areas.

Specifically, step S103 determines whether the ratio of the area of the map region framed by the edgewise travel path of the cleaning robot in each global coordinate axis direction to the area of the map region traversed by the cleaning robot is greater than a preset coverage rate, that is, whether the ratio of the area of the map region framed by the edgewise travel path of the cleaning robot in the horizontal coordinate axis direction to the area of the map region traversed by the cleaning robot is greater than the preset coverage rate, and the ratio of the area of the map region framed by the edgewise travel path of the cleaning robot in the vertical coordinate axis direction to the area of the map region traversed by the cleaning robot is greater than the preset coverage rate, if both determination conditions are satisfied, step S104 is performed, otherwise step S107 is performed. In this embodiment, the preset coverage condition is that a ratio of an area of a map region framed by the edgewise walking path of the cleaning robot in the horizontal coordinate axis direction to an area of a map region traversed by the cleaning robot is greater than a preset coverage, and a ratio of an area of a map region framed by the edgewise walking path of the cleaning robot in the vertical coordinate axis direction to an area of a map region traversed by the cleaning robot is greater than the preset coverage; the global coordinate axis direction comprises a horizontal coordinate axis direction and a vertical coordinate axis direction; when the ratio of the area of the map area framed by the edgewise walking path of the cleaning robot in the horizontal coordinate axis direction to the area of the map area traversed by the cleaning robot is smaller than or equal to the preset coverage rate, or the ratio of the area of the map area framed by the edgewise walking path of the cleaning robot in the vertical coordinate axis direction to the area of the map area traversed by the cleaning robot is smaller than or equal to the preset coverage rate, it is determined that the cleaning robot does not completely walk the global working area for one circle, and the cleaning robot may not return to the preset edgewise starting point. Preferably, a preset coverage is set at 2/3, and this preset coverage is related to the size of the cleaning robot itself and the walking path environment along the edge, and can be modified by the user according to the needs. In the embodiment, from the aspect of coverage rate of the robot walking area, the area of a map area framed by the edgewise walking path of the cleaning robot in the vertical coordinate axis direction or the horizontal coordinate axis direction is fully utilized to represent the coverage integrity of the edgewise walking area, and then the integrity of the edgewise circle is judged.

Before the cleaning robot cleans and traverses the global working area according to a preset cleaning mode, the judging method further comprises the following steps: step S1, setting the side length of the map traversal block according to the size (including the length and width of the map) of the global grid map, so that the map traversal block establishment method occupies a grid area which is large enough in the global grid map; step S2, calculating the covering number of the map traversal blocks in each global coordinate axis direction (including the X-axis direction and the Y-axis direction of a global coordinate system) of the global grid map by combining the dimension of the global grid map and the ratio relation of the side lengths of the map traversal blocks determined in the step S1, wherein the map traversal blocks are equivalent to sub-areas divided by the global grid map; step S3, according to the constraint effect of the coverage number of the map traversal block determined in step S2, performing row-by-row and column-by-column accumulation operation on the side length of the map traversal block determined in step S1 to calculate the mapping coordinates of each map traversal block, so that the map traversal block is established in each row and each column of the global grid map, that is, the coverage number of the map traversal block can determine the boundary information of the global grid map, and the distribution number and the distribution position of the map traversal block in each row and each column of the global grid map are constrained, wherein each map traversal block is formed by combining corresponding grids according to the mapping coordinates and the side length thereof. The invention combines the grids of each row and each column in the map to establish map traversal blocks with a certain size and quantity, each map traversal block corresponds to a small block area occupied in the actual environment, and the robot can plan the general path of the robot by setting the size of the grids slightly larger, thereby reducing the calculated amount and facilitating the robot to process the map information; the map traversal block establishment method realizes the division of the large-scale global grid map into a plurality of map sub-areas, reduces the navigation positioning calculation force requirement and the map data storage space requirement on the mobile robot, saves the calculation resources of the grid surface in the global map and accelerates the data processing speed. The method can be applied to the calculation of the coverage rate and the area of path planning, walking along the edge and recharging path planning. It should be noted that the map traversal blocks of each row of the global grid map are all arranged in the direction of the horizontal coordinate axis and the projections of the map traversal blocks in the direction of the vertical coordinate axis are overlapped, and the map traversal blocks of each column of the global grid map are all arranged in the direction of the vertical coordinate axis and the projections of the map traversal blocks in the direction of the horizontal coordinate axis are overlapped; the global coordinate axis directions include a vertical coordinate axis direction and a horizontal coordinate axis direction. The invention merges grids on the global map row by row and column by column to establish a regularly distributed map traversal block. Equivalent to a small map tile that partitions the global map into blocks.

Preferably, a standard side length E is preset for the map traversal blocks, and the maximum value thereof may be set to 16, so that each map traversal block fills 16X16 grids at maximum. The global grid map corresponding to the global working area of the embodiment is a rectangular map, the map traversal block filling and covering the global grid map is square, and when the length and the width of the global grid map are both greater than 2 times of E, the side length of the map traversal block is set as E; when the length and the width of the global grid map are both larger than E but smaller than 2 times of E, setting the side length of the map traversal block as half of E; and when the length of the global grid map is less than or equal to E or the width of the global grid map is less than or equal to E, setting the side length of the map traversal block to be one fourth of E. Compared with the prior art, the grid expansion processing of the global grid map is realized by every map traversal block formed by 16X16 map grids, so that the map traversal block occupies a grid area large enough in the global grid map, and the robot can conveniently traverse the map path information on the mark adaptation range. Therefore, the size of the grid is slightly larger, only the general path of the robot needs to be planned, the calculated amount is reduced, and the method is suitable for path planning, walking along the edge and recharging path planning.

In this embodiment, a ratio of an effective length of the global grid map to a side length of the map traversal block is calculated, and a processing is performed to obtain a coverage number of the map traversal block established in a vertical coordinate axis direction of the global grid map; and calculating the ratio of the effective width of the global grid map to the side length of the map traversal block, and adding one to process to obtain the coverage quantity of the map traversal block established in the horizontal coordinate axis direction of the global grid map. The necessity of the adding process is that the software system rounds up the ratio of the effective length of the global grid map to the side length of the map traversal block, and omits a decimal part, so that the adding process is needed to ensure that the map traversal blocks with the coverage number completely record the actually covered global working area, and the redundancy of the spatial area is improved.

On the basis of determining the side length of the map traversal block according to the method, the number of the map traversal blocks in each global coordinate axis direction of the global grid map is determined through calculation, and the method specifically comprises the following steps: the number H of map traversal blocks in the vertical coordinate axis direction (i.e., in the length direction) of the global grid map = the ratio of the effective length of the global grid map to the side length of the map traversal block +1, and the number W of map traversal blocks in the horizontal coordinate axis direction (i.e., in the width direction) of the global grid map = the ratio of the effective width of the global grid map to the side length of the map traversal block + 1. The effective length and effective width in this embodiment comprise a grid area traversed by the robot for constructing the map traversal block.

Then, calculating grid coordinates corresponding to each map traversal block, specifically including: step S31, taking the grid position at the lower left corner of the global grid map as a reference origin, and then entering step S32; and calculating the mapping coordinates of the map traversal block by taking the lower left corner of the global grid map as a reference origin. Supposing minx and miny are respectively reference origin coordinates of the global grid map and are also respectively equivalent to the minimum coordinate value on the X axis of the global grid map and the minimum coordinate value on the Y axis of the global grid map; i is set as the offset of the map traversal block relative to the reference origin in the X-axis direction, and i +1 is equivalent to the number of the map traversal blocks of which the mapping coordinates are determined in the horizontal coordinate axis direction; j is set as the offset of the map traversal block relative to the reference origin in the Y-axis direction, and j +1 is equivalent to the number of the map traversal blocks of which the mapping coordinates are determined in the vertical coordinate axis direction; e is the side length of the map traversal block; x (i, j) is a mapping coordinate of the map traversal block in the horizontal coordinate axis direction of the global grid map, and Y (i, j) is a mapping coordinate of the map traversal block in the vertical coordinate axis direction of the global grid map. Step S32, starting from the reference origin coordinate position (minx, miny), adding the reference origin coordinate on the vertical coordinate axis to the side length of the map traversal block to calculate and determine the mapping coordinate of the current map traversal block on the vertical coordinate axis, that is, j =0, to obtain the minimum mapping coordinate Y (i, j) = j = e + miny = miny on the vertical coordinate axis, and at the same time, determine that the mapping coordinate of the current map traversal block on the horizontal coordinate axis is equal to the coordinate minx of the reference origin on the horizontal coordinate axis, and then go to step S33. And S33, judging whether the number j of the map traversal blocks of which the mapping coordinates are determined in the vertical coordinate axis direction is smaller than the coverage number H of the map traversal blocks in the vertical coordinate axis direction of the global grid map, if so, entering S34, and otherwise, entering S35. Step S34, adding the side length of the map traversal block to the currently determined mapping coordinate of the map traversal block on the vertical coordinate axis, calculating and determining the mapping coordinate of the adjacent map traversal block on the vertical coordinate axis in the same vertical coordinate axis direction, namely Y (i, j +1) = (j +1) × e + miny, forming the adjacent Y-axis mapping coordinate in the same vertical coordinate axis direction, and adding one to j automatically every time step S34 is executed; and simultaneously determining the mapping coordinate X (i, j +1) of the horizontal coordinate axis of the adjacent map traversal blocks in the same vertical coordinate axis direction to be the same as the mapping coordinate X (i, j) of the currently determined map traversal block in the horizontal coordinate axis, and then returning to the step S33 to realize that the mapping coordinate of each map traversal block in the same vertical coordinate axis direction is determined line by line under the constraint action of the coverage number in the same vertical coordinate axis direction. Step S35, adding the side length of the map traversal block to the currently determined mapping coordinate of the map traversal block on the horizontal coordinate axis, and calculating and determining the mapping coordinate of the adjacent map traversal block on the horizontal coordinate axis in the same horizontal coordinate axis direction, that is, when i =0, the minimum mapping coordinate X (i, j) = i × e + minx = minx on the horizontal coordinate axis is obtained, wherein, when the step S35 is performed once, i is automatically added; and simultaneously determining the mapping coordinate Y (i +1, j) of the map traversal block adjacent to the map traversal block in the same horizontal coordinate axis direction on the vertical coordinate axis to be the same as the mapping coordinate Y (i, j) of the currently determined map traversal block on the vertical coordinate axis, and then entering step S36 to determine the mapping coordinate of each map traversal block in the same horizontal coordinate axis direction column by column under the constraint action of the coverage number in the same horizontal coordinate axis direction. Step S36, determining whether the number i of map traversal blocks for which the mapping coordinates have been determined in the horizontal coordinate axis direction is smaller than the coverage number W of map traversal blocks in the horizontal coordinate axis direction of the global grid map, if so, returning to step S33, otherwise, determining that the mapping coordinates of each map traversal block in the global grid map have been calculated row by row and column by column, so that the map traversal blocks are established for each row and each column of the global grid map, and the blocking processing of the global grid map is completed. Each row and each column of the foregoing steps refer to each row and each column of the map traversal block distributed in the global grid map. In the foregoing embodiment, according to the map boundary constraint effect caused by the coverage number of the map traversal blocks determined in the foregoing step, row-by-row accumulation operation is performed on the side length of the determined map traversal blocks, including traversing the current row first, and then traversing the next row until the map traversal blocks of all rows distributed in the horizontal coordinate axis direction are traversed, so as to determine the mapping coordinate of each map traversal block, and construct the map traversal block on the regular area block of each row and each column of the global grid map, so as to realize the division of the global grid map into the map traversal blocks.

Therefore, the method for determining whether a grid position coordinate (a, b) of the global grid map belongs to a traversal map tile comprises the following steps: judging whether a is simultaneously greater than or equal to X (i, j) and less than or equal to X (i, j) + e-1; simultaneously judging whether b simultaneously satisfies the condition that the b is more than or equal to Y (i, j) and is less than or equal to Y (i, j) + e-1; when the grid position coordinate (a, b) satisfies the above two determination conditions at the same time, it is determined that the grid position coordinate (a, b) is located within the map traversal block. When the cleaning robot traverses any grid in the map traversal block according to the preset cleaning mode, for example, when the cleaning robot traverses grid position coordinates (a, b), marking the map traversal block corresponding to the cleaning robot as the traversed map traversal block; when the cleaning robot walks edgewise into the interior of the map traversal block and traverses to the grid position coordinates (a, b), meanwhile, the marked map traversal blocks are edgewise map traversal blocks and map traversal blocks which are already walked, so that the edgewise walking path is composed of the edgewise map traversal blocks on the global grid map, the edgewise map traversal blocks are marked as oblique line filling blocks shown in FIGS. 2 to 4, compared with the mode of marking grid one by one, the map traversal block records a larger path area range, the number of the marking blocks used for marking the same path section is reduced, the calculation force requirement and the storage space requirement on the cleaning robot are reduced, and the drawing time is reduced.

Specifically, the calculating the area of the map area framed by the edgewise walking path of the cleaning robot in each global coordinate axis direction of the global grid map includes: and calculating the area of a map area framed by the edgewise walking path of the cleaning robot in the direction of the vertical coordinate axis of the global grid map and calculating the area of a map area framed by the edgewise walking path of the cleaning robot in the direction of the horizontal coordinate axis of the global grid map.

The method for calculating the area of the map area framed by the edgewise walking path of the cleaning robot in the vertical coordinate axis direction of the global grid map comprises the following steps: judging whether one or more than one edgewise map traversal block exists in the map traversal blocks in each row of the global grid map, if so, counting the number of the map traversal blocks from the bottommost edgewise map traversal block to the topmost edgewise map traversal block in the corresponding row, or counting the number of the map traversal blocks from the topmost edgewise map traversal block to the bottommost edgewise map traversal block, and recording the number as the area of the edgewise walking path of the cleaning robot in the defined map area in the row, otherwise, not calculating the area of the edgewise walking path of the cleaning robot in the defined map area in the row; specifically, in the process of statistically calculating the area of the edgewise walking path of the cleaning robot in the framed map area of the column, starting from the minimum mapping coordinate of the map traversal blocks of the column in the Y-axis direction, detecting whether the map traversal blocks are edgewise map traversal blocks (diagonal line filling blocks) one by one along the same Y-axis direction, adding a statistic every time the map traversal blocks are detected to be edgewise map traversal blocks, recording the coordinate position of the edgewise map traversal block farthest from the origin position and the coordinate position of the edgewise map traversal block closest to the origin position after H map traversal blocks in the vertical coordinate axis direction (i.e. in the length direction) of the global grid map are detected, and statistically obtaining the number of the map traversal blocks included between the two edgewise map traversal blocks, including the two edgewise map traversal blocks, if the map traversal blocks detected on the row only have one edgewise map traversal block (the oblique line fills the box), a statistic is added, so that the area of the edgewise walking path of the cleaning robot in the map area of the row is calculated in a framing mode; if there is no edgewise map traversal block on the row, the area of the edgewise walking path of the cleaning robot in the row of map areas cannot be calculated in a framing manner, but regardless of the existence of the edgewise map traversal block, the embodiment keeps calculating the number of map traversal blocks that the cleaning robot has walked, and represents the area of the map area that the cleaning robot has walked.

As shown in the implementation scenario of fig. 3, map traversal blocks in the leftmost column of the room area #2 are all 12 edgewise map traversal blocks traversed by the cleaning robot during the process of walking edgewise, and the number 12 of map traversal blocks between the uppermost edgewise map traversal block and the lowermost edgewise map traversal block in this column is recorded as the area of the map area framed by the edgewise walking path of the cleaning robot in this column; the map traversal block part in the rightmost column of the room area #2 is the edgewise map traversal block traversed by the cleaning robot in the edgewise walking process, and the rest may be formed by combining free grid areas, or before the edgewise walking is started, the cleaning robot performs zigzag cleaning on the traversed map traversal blocks marked in the room area #2, and then the number 12 of the map traversal blocks between the edgewise map traversal block at the uppermost end and the edgewise map traversal block at the bottommost end of the column is recorded as the area of the edgewise walking path of the cleaning robot in the framed map area of the column; when the map traversal blocks of all the columns of the room area #2 are judged according to the foregoing steps, a rectangular dotted line area N1N2N11N7 is framed, and the number of all the map traversal blocks inside this rectangular dotted line area N1N2N11N7 is the area of the map area framed in the vertical axis direction of the room area #2 along the side travel path of the cleaning robot.

Similarly, map traversal blocks in a column at the leftmost end of the room area #1 are all the edgewise map traversal blocks traversed in the process of the cleaning robot walking edgewise, and the number 3 of the map traversal blocks between the edgewise map traversal block at the uppermost end and the edgewise map traversal block at the lowermost end in the column is recorded as the area of the map area framed by the column along the walking path of the cleaning robot; two continuous adjacent columns at the leftmost end of the room area #1 are only provided with one edgewise map traversal block at the bottommost end, and the rest of the edgewise map traversal blocks may be combined by idle grid areas, or before the edgewise walking is started, the cleaning robot performs zigzag cleaning on the traversed map traversal blocks marked in the room area #1, and then the two columns are also used for calculating the area of the edgewise walking path of the cleaning robot in the map area framed by the corresponding column; when all the rows of map traversal blocks of the room area #1 are judged according to the foregoing steps, a rectangular dotted line area N9N6N8N10 is framed with 5 of the edgewise map traversal blocks at the left end thereof, and the number of all the map traversal blocks included inside them is the area of the map area framed by the edgewise travel path of the cleaning robot in the vertical axis direction of the room area #1, and then the number of all the map traversal blocks inside the aforementioned rectangular dotted line area N1N2N11N7 is added, so that the area of the map area framed by the edgewise travel path of the cleaning robot in the vertical axis direction of the global grid map is obtained. It is to be noted that, since the door of the room area #3 shown in fig. 3 is closed, unlike the door of the room area #3 of fig. 2 and 4, which is opened, the cleaning robot does not walk along the inside of the room area #3 shown in fig. 3, and does not need to take into account the area of the map area framed by its traveling path along the vertical axis of the room area # 3. According to the embodiment, the area of the map area framed by the side walking path in the vertical coordinate axis direction of the global coordinate system can completely represent the coverage area condition of the cleaning robot in the Y-axis direction of the current side walking path, the room boundary environment characteristics are reflected, and the calculation amount of the grid area in the global map in the prior art is reduced by using the map traversal block. Among them, the width of the walls between the room areas of the global work area of fig. 3, such as wall M1 between room area #3 and room area #2, wall M2 between room area #3 and room area #1, and wall M3 between room area #2 and room area #1, is negligible with respect to the body size of the cleaning robot, and during the edgewise walking of the cleaning robot from room area #1 into room area #2, the side length of the map traversal block traversed by the cleaning robot across wall M3 is negligible.

The method for calculating the area of the map area framed by the edgewise walking path of the cleaning robot in the horizontal coordinate axis direction of the global grid map comprises the following steps: judging whether one or more than one edgewise map traversal block exists in the map traversal blocks in each row of the global grid map, if so, counting the number of the map traversal blocks from the leftmost edgewise map traversal block to the rightmost edgewise map traversal block, or counting the number of the map traversal blocks from the rightmost edgewise map traversal block to the leftmost edgewise map traversal block, and recording the number as the area of the edgewise walking path of the cleaning robot in the map area framed by the row, otherwise, not calculating the area of the edgewise walking path of the cleaning robot in the map area framed by the row; specifically, in the process of statistically calculating the area of the borderline travel path of the cleaning robot in the map area framed in the line, starting from the minimum mapping coordinate of the map traversal block in the X-axis direction in the line, detecting whether the map traversal block is a borderline map traversal block (diagonal filling block) one by one along the same X-axis direction, counting each time when the map traversal block is detected as a borderline map traversal block, recording the coordinate position of the borderline map traversal block farthest from the origin position and the coordinate position of the borderline map traversal block closest from the origin position after detecting W map traversal blocks in the horizontal coordinate axis direction (i.e. in the width direction) of the global grid map, and statistically obtaining the number of map traversal blocks included between the two borderline map traversal blocks, including the two borderline map traversal blocks, if the map traversal block detected on the row only has one edgewise map traversal block (the oblique line fills the square block), adding a statistic so as to accumulatively calculate the area of the edgewise walking path of the cleaning robot in the map area; if there is no edgewise map traversal block on the line, the area of the edgewise travel path of the cleaning robot in the map area of the line cannot be calculated in a framing manner, but regardless of the existence of the edgewise map traversal block, the present embodiment keeps calculating the number of map traversal blocks that the cleaning robot has traveled, which represents the area of the map area that the cleaning robot has traveled.

As shown in the implementation scenario of fig. 3, the map traversal blocks in the uppermost row of the room area #2 are all 8 of the edgewise map traversal blocks traversed by the cleaning robot during the process of walking edgewise, and the number of the map traversal blocks from the edgewise map traversal block at the leftmost end to the edgewise map traversal block at the rightmost end in this row is 8, which is recorded as the area of the edgewise walking path of the cleaning robot in the framed map area in this row. Counting from top to bottom along the vertical coordinate axis (Y axis), wherein the edgewise map traversal blocks are arranged at two ends of the second row and the third row, the inner map traversal blocks of the two rows are partially the edgewise map traversal blocks traversed by the cleaning robot in the edgewise walking process, and the rest map traversal blocks can be formed by combining idle grid areas, or the walking map traversal blocks marked by the cleaning robot in a bow-shaped cleaning way in a room area #2 before the edgewise walking is started can be calculated, so that the area of the edgewise walking path of the cleaning robot in the two rows of framed map areas can be calculated; after counting to the fourth row, only one edgewise map traversal block exists on the fourth, fifth and sixth rows, and the edgewise map traversal block is also used for counting the area of the map area framed by the edgewise travel path of the cleaning robot in the corresponding row, so that the edgewise travel path of the cleaning robot frames a rectangular dotted-line area N1N2N3N4 and three edgewise map traversal blocks in the above six rows. When the seventh row of the room area #2 is judged according to the previous steps, it is judged that the room area #2 and the room area #1 are marked with the edgewise map traversal blocks on the row, then the number of the map traversal blocks between the edgewise map traversal block at the leftmost end of the row of the room area #2 and the edgewise map traversal block at the rightmost end of the row of the room area #1 is counted to be 14, the area of the defined map area of the edgewise walking path of the cleaning robot on the row is recorded, and the width of the indoor wall is smaller than the size of the cleaning robot and can be ignored. When the map traversal blocks in the lowest row of the working scene shown in fig. 3 are judged according to the above steps, a rectangular dotted line region N5N6N7N8 is framed, the number of all the map traversal blocks in the rectangular dotted line region N5N6N7N8 is that the area of the map region framed in the horizontal coordinate axis direction by the seventh to twelfth rows of the edgewise walking path is counted from top to bottom along the vertical coordinate axis (Y axis) direction by the cleaning robot, and then the number of all the map traversal blocks in the rectangular dotted line region N1N2N3N4 is added, so that the area of the map region framed by the edgewise walking path of the cleaning robot in the horizontal coordinate axis direction of the global grid map is obtained. According to the embodiment, the area of the map area framed by the edgewise walking path in the horizontal coordinate axis direction of the global coordinate system can completely represent the coverage condition of the cleaning robot in the X-axis direction of the edgewise walking at present, and the use of the map traversal block also reduces the calculation amount of the grid area in the global map in the prior art.

In the implementation scenario of fig. 3, the cleaning robot walks along the edge of the gate of the room area #3, but the gate is not opened, the cleaning robot can only continue to walk along the edge of the gate in the room area #2, the cleaning robot calculates at the current position that the sum of the area of the map area framed by the path of the cleaning robot along the path of the cleaning robot in the direction of the vertical coordinate axis of the global grid map is the area of the rectangular dotted line area N1N2N11N7, the area of the rectangular dotted line area N9N6N8N10 and the 5 traversal blocks of the map along the left end thereof, which is already greater than the preset coverage ratio 2/3 of the area of all the traversed map areas of the cleaning robot, but the area of the map area framed by the path of the cleaning robot along the path in the direction of the horizontal coordinate axis of the global grid map is the area of the rectangular area N1N2N3N4, 2/3 of the area of the rectangular area N5N6N7N8 and the sum of the areas of the 3 edgewise map traversal blocks in between, which do not occupy all the traversed map area of the cleaning robot, may determine that the cleaning robot has not completely edgewise traversed the global working area by one turn, and after all the previously cleared room area #3 has not been edgewise traversed, and even if the cleaning robot continues to edgewise walk from the room area #2, it returns for the first time to the preset edgewise starting point a of the room area #1, so that the field area of the map area framed by the edgewise walking path of the cleaning robot in the horizontal coordinate axis direction of the global map grid is first greater than 2/3 of the area of all the traversed map areas of the cleaning robot, and it cannot be determined that the cleaning robot has completely edgewise traversed the global working area by one turn. Therefore, it is necessary to proceed to step S104 for further determination.

In summary, compared with the prior art, in each row of map traversal blocks of the global grid map, the area of the map area framed by the edgewise walking path in the vertical coordinate axis direction of the global grid map is calculated by counting the number of the map traversal blocks included between the edgewise map traversal block at the lowermost end and the edgewise map traversal block at the uppermost end; in each row of map traversal blocks of the global grid map, calculating the area of a map area framed by the edgewise walking path in the horizontal coordinate axis direction of the global grid map by counting the number of the map traversal blocks included between the edgewise map traversal block at the leftmost end and the edgewise map traversal block at the rightmost end; furthermore, the area of a map area framed by the edge walking path in each coordinate axis direction of the global coordinate system can completely represent the coverage area of the cleaning robot walking along the edge, and the use of the map traversal block also reduces the calculation amount of the grid area in the global map in the prior art.

As an embodiment, the relative position relationship between the current position of the cleaning robot and the preset edgewise starting point meets a registration error condition includes: the distance between the grid coordinate point of the current position of the cleaning robot on the global grid map and the line segment of the preset edgewise starting point on the grid coordinate point of the global grid map meets the preset drifting threshold condition, and the optimal path searched between the current position of the cleaning robot and the preset edgewise starting point meets the preset coincident positioning condition. Preferably, when the ratio of the area of the map region framed by the edgewise walking path of the cleaning robot in each global coordinate axis direction of the global grid map to the area of the map region traversed by the cleaning robot all meets the preset coverage condition, and the distance between the grid coordinate point of the current position of the cleaning robot on the global grid map and the line segment of the preset edgewise starting point on the grid coordinate point of the global grid map meets the preset drift threshold condition, if the optimal path searched between the current position of the cleaning robot and the preset edgewise starting point meets the preset coincident positioning condition, it is determined that the cleaning robot has completely walked for one circle along the global working region and returned to the preset edgewise starting point. The method comprises the following specific steps:

and step S104, judging whether the distance between the grid coordinate point of the current position of the cleaning robot on the global grid map and the line segment of the preset edge starting point on the grid coordinate point of the global grid map is smaller than a preset drift error threshold value, if so, entering step S105, otherwise, entering step S107. The preset drift error threshold value is set according to the following judgment: as the errors of the visual sensor of the cleaning robot for positioning are accumulated, a map drift error may occur in the global grid map shown in fig. 2 to 4, so that the current position of the cleaning robot may have a map grid position drift phenomenon, and as long as the length of the line connecting the preset edge starting point a and the current position of the cleaning robot is within a certain map drift error range, the robot may be considered to be able to return to the preset edge starting point from the current position; when the length of the line connecting the preset edgewise starting point A and the current position of the cleaning robot exceeds the map drift error range, the grid coordinate drift degree of the current position of the cleaning robot is too serious, so that the cleaning robot cannot return to the preset edgewise starting point A, and the cleaning robot is determined to not completely walk along the global working area for one circle.

In the working scenario embodiment shown in fig. 4, the width of the wall M2, the width of the wall M1, and the width of the wall M3 are all smaller than the size of the cleaning robot, the size of the grid occupied by the aforementioned walls is negligible, the cleaning robot starts from a preset edgewise starting point a in the room area #1, walks edgewise along the global working area, and walks anticlockwise around the global working area to the position D of the room area #3, meanwhile, the map areas framed by dotted lines in each global coordinate axis direction of the global grid map along the edgewise walking path of the cleaning robot are all rectangular areas P1P2P3P4, and the ratio of the area of the rectangular area P1P2P3P4 to the area of the map area traversed by the cleaning robot is greater than the preset coverage rate, so as to satisfy the preset coverage rate condition.

When the connection distance between the coordinate point of the current position D of the cleaning robot on the global grid map and the coordinate point of the preset edgewise starting point A on the global grid map is smaller than a preset drift error threshold value, the current position D of the cleaning robot, the preset edgewise starting point A and a wall M2 for isolating the cleaning robot from the preset edgewise starting point A drift within a certain map drift error range, wherein the wall M2 keeps isolating the current position D of the cleaning robot from the preset edgewise starting point A in the drifting process, so that the preset edgewise starting point A cannot drift to the current position D of the cleaning robot. At this time, the cleaning robot is still in the room zone #3 and still has a wall separation from the room zone #1, the cleaning robot does not completely follow the global working zone for one turn, and the cleaning robot does not return to the preset edge starting point, so that the step S105 still needs to be performed for further grid data judgment.

On the other hand, on the premise that the ratio of the area of the map region framed by the border walking path of the cleaning robot in each global coordinate axis direction of the global grid map to the area of the map region traversed by the cleaning robot meets the preset coverage rate condition, if the connection distance between the coordinate point of the current position of the cleaning robot on the global grid map and the coordinate point of the preset border starting point a on the global grid map is greater than or equal to the preset drift error threshold value, the drift of the global grid map exceeds the map drift error range allowed by the visual cleaning robot, and the problem that a relatively serious map drift error exists between the current position of the cleaning robot and the preset border starting point is determined, so that the cleaning robot cannot return to the preset border starting point a from the current position. Therefore, the embodiment of step S104 uses the distance between the current position of the cleaning robot and the coordinate connection line of the preset edge starting point on the global grid map as the prejudgment condition for the robot to return to the preset edge starting point.

And S105, judging whether the number of grids contained in the optimal path searched between the current position of the cleaning robot and the preset edge starting point A is less than the preset path grid number, if so, entering S106, and otherwise, entering S107. As shown in fig. 2, since the width of the wall M2, the width of the wall M1, and the width of the wall M3 are all smaller than the size of the cleaning robot, the size of the grid occupied by the aforementioned walls is negligible, the map area framed by the dotted lines of the edge-following walking path in each global coordinate axis direction of the global grid map is a rectangular area O1O2O3O4, and on the premise that the connection distance between the grid coordinate point of the current position of the cleaning robot on the global grid map and the grid coordinate point of the preset edge-following starting point a on the global grid map meets the preset drift threshold condition, and the traversable path distance between the current position of the cleaning robot searched by this embodiment and the preset edge-following starting point a is determined to meet the preset registration condition when the grid number included in the optimal path searched out between the current position of the cleaning robot and the preset edge-following starting point a is smaller than the grid number of the preset path, and then according to the condition that the planned path actually returned to the preset edgewise starting point A is obtained, the current position of the cleaning robot is considered to be capable of being overlapped with the preset edgewise starting point, so that the cleaning robot returns to the preset edgewise starting point A by completely following the global working area shown in the figure 2 for one circle. In addition, if the number of grids included in the optimal path searched out between the current position of the cleaning robot and the preset edgewise starting point is greater than the number of grids in the preset path, the cleaning robot cannot search out the preset edgewise starting point a at the current position, and it is determined that the current position of the cleaning robot has deviated from the preset edgewise starting point a, which may be considered that the cleaning robot is far away from the preset edgewise starting point a. In step S105, the optimal path length searched between the current position of the cleaning robot and the preset edge starting point is used to determine the overlapping location condition between the current position of the cleaning robot and the preset edge starting point, so as to help the robot return to the preset edge starting point from the current position according to the shortest path selected in the step. Further improving the positioning accuracy of the cleaning robot along one circle and the judgment accuracy of the complete edge.

Preferably, the optimal path searched between the current position of the cleaning robot and the preset edgewise starting point is: and according to the current position of the robot and the preset edge starting point, calculating a shortest path by using an A-x algorithm to serve as an optimal path for the robot to navigate back to the preset edge starting point. Since the algorithm a searches for the optimal path between the starting location and the target location is a conventional algorithm, it is not described herein again.

And S106, determining that the cleaning robot has returned to the preset edgewise starting point, and completely walking for one circle along the global working area.

And S107, determining that the cleaning robot does not return to the preset edge starting point, and the cleaning robot does not completely walk along the global working area for one circle.

In the above embodiment, the preset coverage, the preset drift error threshold and the preset path grid number are all related to the size of the cleaning robot and the edgewise walking path, and a user can modify the preset coverage, the preset drift error threshold and the preset path grid number according to needs. In the embodiments of fig. 2 to 4, if the global area that the cleaning robot is expected to sweep is larger or smaller, the preset coverage rate may be increased or decreased correspondingly; and if the size of the body of the cleaning robot is larger, correspondingly increasing the preset drift error threshold value and the preset path grid number.

The embodiment of the invention also discloses a chip, which is internally provided with a control program, wherein the control program is used for controlling the judging method of the cleaning robot, so that the control program comprises part or all steps of the judging method. It is to be understood that the embodiments described herein may be implemented by hardware, software, firmware, middleware, microcode, or any combination thereof. For a hardware implementation, the processing units may be implemented within one or more Application Specific Integrated Circuits (ASICs), Digital Signal Processors (DSPs), Digital Signal Processing Devices (DSPDs), Programmable Logic Devices (PLDs), Field Programmable Gate Arrays (FPGAs), processors, controllers, micro-controllers, microprocessors, other electronic units designed to perform the functions described herein, or a combination thereof. When the embodiments are implemented in software, firmware, middleware or microcode, program code or code segments, they can be stored in a machine-readable medium, such as a storage component.

The chip is arranged in the visual robot and is used for overcoming the influence of map drift in the process of executing the judgment method by the visual robot. It should be noted that only the cleaning robot with visual navigation uses the preset drift threshold condition to perform drift judgment of the current position in the global grid map, and the cleaning robot with inertial navigation cannot use this method, because the grid map has a chance of error at a high probability in the inertial navigation process, and the map constructed by laser navigation is relatively accurate, the problem of drift of the laser grid map basically does not occur, but the cost is high and the software control is complex.

The logic and/or steps represented in the flowcharts or otherwise described herein, e.g., an ordered listing of executable instructions that can be considered to implement logical functions, can be embodied in any computer-readable medium for use by or in connection with an instruction execution system, apparatus, or device, such as a computer-based system, processor-containing system, or other system that can fetch the instructions from the instruction execution system, apparatus, or device and execute the instructions. For the purposes of this description, a "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of the computer-readable medium would include the following: an electrical connection (electronic device) having one or more wires, a portable computer diskette (magnetic device), a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disc read-only memory (CDROM). Additionally, the computer-readable medium could even be paper or another suitable medium upon which the program is printed, as the program can be electronically captured, via for instance optical scanning of the paper or other medium, then compiled, interpreted or otherwise processed in a suitable manner if necessary, and then stored in a computer memory.

The above embodiments are merely illustrative of the technical ideas and features of the present invention, and are intended to enable those skilled in the art to understand the contents of the present invention and implement the present invention, and not to limit the scope of the present invention. All equivalent changes or modifications made according to the spirit of the present invention should be covered within the protection scope of the present invention.

Claims

1. A method for determining a turn along a global operating region, comprising: controlling the cleaning robot to clean and traverse the global working area according to a preset cleaning mode, and constructing a global grid map according to information recorded in the cleaning and traversing process;

it is characterized by also comprising: after the global working area is cleaned, controlling the cleaning robot to walk edgewise in the global working area from a preset edgewise starting point, and meanwhile calculating the area of a map area framed by an edgewise walking path of the cleaning robot in each global coordinate axis direction of the global grid map and the area of the map area traversed by the cleaning robot; the method comprises the following steps that the areas of all traversed map areas of a cleaning robot are calculated from the time when the cleaning robot sweeps and traverses a global working area according to a preset sweeping mode;

when the ratio of the area of a map region framed by the edgewise walking path of the cleaning robot in each global coordinate axis direction of the global grid map to the area of the map region traversed by the cleaning robot meets a preset coverage condition, and the relative position relationship between the current position of the cleaning robot and a preset edgewise starting point meets a superposition error condition, determining that the cleaning robot completely walks for a circle along the global working region.

2. The determination method according to claim 1, wherein the preset coverage condition is that a ratio of an area of a map region framed by the edgewise travel path of the cleaning robot in the direction of the horizontal coordinate axis to an area of a map region traversed by the cleaning robot is larger than a preset coverage, and a ratio of an area of a map region framed by the edgewise travel path of the cleaning robot in the direction of the vertical coordinate axis to an area of a map region traversed by the cleaning robot is larger than a preset coverage; the global coordinate axis direction comprises a horizontal coordinate axis direction and a vertical coordinate axis direction;

when the ratio of the area of a map region framed by the edgewise walking path of the cleaning robot in the horizontal coordinate axis direction to the area of all the traversed map regions of the cleaning robot is smaller than or equal to the preset coverage rate, or the ratio of the area of the map region framed by the edgewise walking path of the cleaning robot in the vertical coordinate axis direction to the area of all the traversed map regions of the cleaning robot is smaller than or equal to the preset coverage rate, determining that the cleaning robot does not completely walk for one circle along the global working region.

3. The method as claimed in claim 2, further comprising, before the cleaning robot performs sweeping traversal on the global working area according to a preset sweeping manner:

setting the side length of a map traversal block according to the size of the global grid map, and determining the coverage quantity of the map traversal blocks in all global coordinate axis directions of the global grid map by calculating the ratio relation between the size of the global grid map and the side length of the map traversal block on the basis of the side length of the map traversal block;

then calculating mapping coordinates of the map traversal blocks by combining the side lengths and the number of the map traversal blocks, and laying the map traversal blocks to each row and each column of the global grid map;

the map traversal blocks of each row of the global grid map are arranged in the direction of the horizontal coordinate axis and the projections of the map traversal blocks in the direction of the vertical coordinate axis are overlapped, and the map traversal blocks of each column of the global grid map are arranged in the direction of the vertical coordinate axis and the projections of the map traversal blocks in the direction of the horizontal coordinate axis are overlapped;

and each map traversal block is formed by combining grids of the global grid map according to the mapping coordinates of the map traversal block.

4. The determination method according to claim 3, wherein when the cleaning robot traverses any grid inside the map traversal block, the corresponding map traversal block is marked as a traversed map traversal block;

when the cleaning robot walks into the interior of the map traversal block along the edge, the map traversal block is marked as the edge map traversal block and the map traversal block which has already walked, so that the edge walking path is composed of the edge map traversal blocks.

5. The determination method according to claim 4, wherein the calculating an area of a map area framed in each global coordinate axis direction of the global grid map by the edgewise travel path of the cleaning robot includes:

calculating the area of a map area framed by the edgewise walking path of the cleaning robot in the vertical coordinate axis direction of the global grid map and calculating the area of a map area framed by the edgewise walking path of the cleaning robot in the horizontal coordinate axis direction of the global grid map;

the method for calculating the area of the map area framed by the edgewise walking path of the cleaning robot in the vertical coordinate axis direction of the global grid map comprises the following steps:

judging whether the edgewise map traversal blocks exist in the map traversal blocks of each row of the global grid map, if so, counting the number of the map traversal blocks from the edgewise map traversal block at the lowest end to the edgewise map traversal block at the highest end in the corresponding row, and recording the number as the area of the edgewise walking path of the cleaning robot in the defined map area of the row; the map area framed by each row of the edgewise walking path of the cleaning robot comprises the bottommost edgewise map traversal block and the topmost edgewise map traversal block in the same row;

when map traversal blocks of all rows of the global grid map are judged according to the steps, setting the sum of the areas of the map areas framed by the border walking path of the cleaning robot in each row as the area of the map area framed by the border walking path of the cleaning robot in the vertical coordinate axis direction of the global grid map;

the method for calculating the area of the map area framed by the edgewise walking path of the cleaning robot in the horizontal coordinate axis direction of the global grid map comprises the following steps:

judging whether the border map traversal blocks exist in each row of the global grid map, if so, counting the number of the map traversal blocks from the border map traversal block at the leftmost end to the border map traversal block at the rightmost end on the corresponding row, and recording the number as the area of the border walking path of the cleaning robot in the framed map area of the row; the map area framed by each row of the edgewise walking path of the cleaning robot comprises the edgewise map traversal block at the leftmost end and the edgewise map traversal block at the rightmost end of the same row;

and when the map traversal blocks of all the rows of the global grid map are judged according to the steps, setting the sum of the areas of the map areas framed by the edge walking path of the cleaning robot in each row as the area of the map area framed by the edge walking path of the cleaning robot in the horizontal coordinate axis direction of the global grid map.

6. The method according to claim 2, wherein the determining that the relative positional relationship between the current position of the cleaning robot and the preset edgewise start point satisfies the registration error condition includes:

the distance between the grid coordinate point of the current position of the cleaning robot on the global grid map and the line segment of the preset edgewise starting point on the grid coordinate point of the global grid map meets the preset drifting threshold condition, and the optimal path searched between the current position of the cleaning robot and the preset edgewise starting point meets the preset coincident positioning condition.

7. The determination method according to claim 6, wherein the preset drift threshold condition is that a distance between a grid coordinate point of the current position of the cleaning robot on the global grid map and a line segment of the preset edge starting point on the grid coordinate point of the global grid map is smaller than a preset drift error threshold value;

and when the connection line distance between the coordinate point of the current position of the cleaning robot on the global grid map and the coordinate point of the preset edge starting point on the global grid map is greater than or equal to a preset drift error threshold value, determining that the cleaning robot does not return to the preset edge starting point.

8. The method according to claim 7, wherein the predetermined registration condition is that the number of grids included in the optimal path searched between the current position of the cleaning robot and the predetermined edge starting point is smaller than the number of grids of the predetermined path;

and on the premise that the connection distance between the grid coordinate point of the current position of the cleaning robot on the global grid map and the grid coordinate point of the preset edge starting point on the global grid map meets the preset drift threshold condition, if the number of grids contained in the optimal path searched between the current position of the cleaning robot and the preset edge starting point is greater than the number of grids in the preset path, determining that the cleaning robot does not return to the preset edge starting point.

9. The judging method according to claim 8, wherein the optimum path searched between the current position of the cleaning robot and the preset edgewise starting point is:

and according to the current position of the cleaning robot and the preset edge starting point, calculating a shortest path by using an A-x algorithm to be used as an optimal path for the cleaning robot to navigate back to the preset edge starting point.

10. A chip having a control program embedded therein, wherein the control program is configured to control a cleaning robot to perform the determination method according to any one of claims 1 to 9.

11. A visual robot having the chip of claim 10 built therein.