WO2014089922A1

WO2014089922A1 - Covering method of map self-established by mobile platform in unknown region

Info

Publication number: WO2014089922A1
Application number: PCT/CN2013/070267
Authority: WO
Inventors: 肖双良
Original assignee: 深圳市银星智能科技股份有限公司
Priority date: 2012-12-12
Filing date: 2013-01-09
Publication date: 2014-06-19
Also published as: CN102968122A

Abstract

This application provides a covering method of a map self-established by a mobile platform in an unknown region. A virtual map is established in advance. The method comprises: 1) when the mobile platform enters the unknown region, enabling the current position of the mobile platform to correspond to a subregion in which the original point of the virtual map is located; 2) marking the subregion corresponding to the current position of the mobile platform as a traversed subregion and marking other subregions as non-traversed subregions; 3) marking the non-traversed subregion adjacent to the traversed subregion as a target subregion; 4) moving the mobile platform to the region corresponding to the target subregion; 5) marking the subregion corresponding to the current position of the mobile platform as the traversed subregion, and determining a target subregion from the non-traversed subregions adjacent to the traversed subregion; and 6) repeating the steps 4) and 5) until no target subregion exists. The method provided by this application is simple in realization, high in converge rate and capable of reducing the repeated coverage rate of the mobile platform in the unknown region.

Description

Covering method for self-built map of mobile platform in unknown area

This application claims priority to Chinese Patent Application No. 201210535501.0, entitled "A Coverage Method for Self-built Maps of Mobile Platforms in Unknown Areas", submitted to the Chinese Patent Office on December 12, 2012. The content is incorporated herein by reference.

Technical field

The present invention relates to the field of mobile platform technologies, and in particular, to a method for overlaying a mobile platform to build a map in an unknown area.

Background technique

The path planning of the mobile platform in the unknown area has always been the focus and difficulty in the mobile platform field. Because there may be obstacles in the unknown area, the mobile platform cannot achieve full coverage of the area.

In view of the above problems, Chinese patent ZL02137830.4 discloses a path planning method for a smart vacuum cleaner, which performs coverage cleaning after determining the boundary of an unknown area, but when there is an obstacle in the unknown area, the obstacle is first The boundary is confirmed and the cleaning action is performed. The algorithm is very complicated. At the same time, the smart vacuum cleaner repeatedly repeats the cleaned area and reduces the cleaning efficiency of the smart vacuum cleaner. The patent document published in Chinese Patent Application No. 201010106562.6 discloses a Chinese patent. An improvement of the technical solution of ZL02137830.4, which achieves coverage of the entire area by compensating for uncovered areas, but this solution is not suitable for situations where there are excessive obstacles in the work area.

Summary of the invention

In view of the above, the present invention provides a method for covering a self-built map of a mobile platform in an unknown area, which is used to solve the problem that the prior art algorithm is complicated and the coverage rate is low. The technical solution is as follows:

A method for overlaying a self-built map of a mobile platform in an unknown area, pre-establishing a virtual map centering on a starting point and including a plurality of sub-areas, the method comprising:

(1) when the mobile platform enters an unknown area, the current location of the mobile platform is corresponding to the sub-area where the starting point of the virtual map is located;

(2) marking, in the virtual map, a sub-region corresponding to a current location of the mobile platform as a traversed sub-region, and marking other sub-regions in the virtual map as non-traversing sub-regions;

(4) moving the mobile platform into an area corresponding to the target sub-area; (5) marking the sub-region corresponding to the current position of the mobile platform in the virtual map as having traversed the sub-region, and determining a target sub-region from the untraversed sub-region adjacent to the traversed region;

(6) Repeat steps (4) through (5) until there is no target sub-area in the virtual map. During the moving process, if an obstacle is detected, the target sub-area is marked as an obstacle sub-area, and then returns to step (3).

Optionally, the method further includes: if the mobile platform cannot reach a target sub-area through the traversed area, mark the target sub-area as an obstacle sub-area, and then return to step (3).

Preferably, the diameter of the minimum coverage circle of each sub-area in the virtual map pre-established by the map storage system is less than or equal to 1/2 of the diameter of the mobile platform in the virtual map, wherein the minimum coverage circle is the edge of the sub-area The two endpoints separated by the furthest distance are circular in diameter.

Preferably, each sub-area in the pre-established virtual map has the same shape and size. Preferably, the shape of each sub-area in the pre-established virtual map is square. Preferably, the shape of each sub-area in the pre-established virtual map is a regular hexagon. Compared with the prior art, the present invention has the following beneficial effects:

The present invention divides the unknown area to be covered by the mobile platform into the traversed sub-area and the untraversed sub-area, and the mobile platform covers the entire unknown area by setting the target sub-area in the sub-area adjacent to the traversed area. The algorithm of the method is simple, the coverage rate is high, and the repeated coverage of the mobile platform in the unknown area is reduced, and the coverage efficiency is improved.

DRAWINGS

FIG. 1 is a schematic flowchart of a method for overlaying a self-built map of a mobile platform in an unknown area according to Embodiment 1 of the present invention;

2 is a schematic diagram of a mobile platform in an unknown area according to Embodiment 1 of the present invention;

3 is a schematic diagram of the mobile platform in FIG. 2 in a virtual map of the map storage system; FIG. 4 is a schematic diagram of the mobile platform marking adjacent sub-areas in FIG. 3;

5 is a schematic diagram of a mobile platform selection target sub-area in FIG. 3;

6 is a schematic diagram of the mobile platform of FIG. 2 after entering the target sub-area;

7 is a schematic diagram of the mobile platform in FIG. 6 in a virtual map of the map storage system; FIG. 8 is a schematic diagram of the mobile platform selecting a target sub-area in FIG. 9 is a schematic diagram of the mobile platform of FIG. 7 selecting another adjacent sub-region as a target sub-region; FIG. 10 is a schematic diagram of the mobile platform of FIG. 2 after completing the traversal of the unknown region;

11 is a schematic diagram of the mobile platform of FIG. 10 after traversing in a virtual map of the map storage system;

12 is a schematic diagram of a mobile platform in an unknown area in Embodiment 2 of the present invention;

13 is a schematic diagram of the mobile platform in FIG. 12 in a virtual map of the map storage system; FIG. 14 is a schematic diagram of the mobile platform marking adjacent sub-areas in FIG.

Figure 15 is a schematic diagram of the mobile platform selection target sub-area of Figure 13;

Figure 16 is a schematic diagram of the mobile platform of Figure 12 after entering the target sub-area;

17 is a schematic diagram of the mobile platform in FIG. 16 in a virtual map of the map storage system; FIG. 18 is a schematic diagram of the mobile platform selection target sub-area in FIG.

19 is a schematic diagram of the mobile platform of FIG. 17 selecting another adjacent sub-region as a target sub-region;

20 is a schematic diagram of the mobile platform of FIG. 12 after completion of traversal of an unknown area;

21 is a schematic diagram of the mobile platform of FIG. 20 after traversing in a virtual map of the map storage system;

Figure 22 is a schematic diagram of the mobile platform and the obstacle sub-area in the case where the minimum coverage circle diameter of the sub-area is greater than the minimum width 1//2 through which the mobile platform can pass;

Figure 23 is a schematic diagram of the mobile platform and the obstacle sub-area in the case where the minimum coverage circle diameter of the sub-area is less than or equal to the minimum width 1//2 through which the mobile platform can pass;

Figure 24 is a schematic diagram showing a sub-region in a virtual map of a map storage system being a regular hexagon.

detailed description

In order to further understand the invention, the preferred embodiments of the present invention are described in the accompanying drawings.

The mobile platform implementing the method of the present invention needs to include at least the following functional modules:

Drive system: Used to displace the mobile platform, such as the drive wheel of a cleaning robot, or the walking mechanism of animals such as humans in bionics.

Obstacle detection system: used to detect obstacles around the mobile platform and generate obstacles after sensing obstacles The control system transmitted to the mobile platform includes non-contact sensors such as infrared sensors, ultrasonic sensors, etc., as well as contact sensors such as voltage sensors, mechanical switch sensors, and the like.

Relative positioning system: It is used to determine the relative position of the moving platform in the region before the movement relative to the moving area, including the direction and distance. For example, the inertial navigation system can be used to calculate the acceleration integral of the mobile platform (using the acceleration). The angular velocity integral (using a gyroscope) is used to obtain relevant information, or the encoder wheel mounted on the driving wheel of the mobile platform is used to calculate the moving distance of the walking wheel to determine the relative position.

Map storage system: Create a large enough virtual map composed of multiple sub-areas and store the information of each sub-area. You can use a widely used memory chip or memory to represent the information of a sub-area with one byte of data: 0 is used to represent sub-regions that have not been traversed, 1 is used to represent sub-regions that have been traversed, and 2 is used to represent sub-regions with obstacles. In addition, the map storage system can also change the information of non-traversed sub-regions from 0 to 1 (traversed Sub-area) or 2 (sub-area with obstacles), then save and update the virtual map. The information marks 0, 1 and 2 of this embodiment are only for distinguishing the states indicating the respective sub-areas, and any character or data may be used to represent different areas as long as they can be recognized by the map storage system.

Control system: used to control the overall working state of the mobile platform: including causing the mobile platform to perform predetermined actions, and controlling the driving system to change the motion and the moving direction of the mobile platform according to the information fed back by the obstacle detecting system.

Embodiment 1

Embodiment 1 of the present invention provides a method for overlaying a self-built map of a mobile platform in an unknown area, and pre-establishes a virtual map centered on a starting point and including a plurality of sub-areas, and FIG. 1 is a schematic flowchart of the method. Methods can include:

S101: When the mobile platform enters the unknown area, the current location of the mobile platform corresponds to the sub-area where the starting point of the map storage system is located.

2 is a schematic diagram of the mobile platform M in the unknown area in the embodiment, wherein the dotted line mark is convenient for the technician to understand the division of the actual area and corresponding to the sub-area in the virtual map, that is, the mobile platform M is in actual Each location in the unknown area has a sub-area in the virtual map that corresponds to it. Among them, the black area in Figure 2 indicates the obstacle or boundary, and the white indicates the blank area.

S102: Mark the sub-region corresponding to the current location of the mobile platform in the virtual map as having been traversed Area, marks other sub-areas in the virtual map as not traversing sub-areas.

As shown in FIG. 3, in the virtual map, the sub-region corresponding to the current position of the mobile platform M (the region where the circle is located) is marked as 1, indicating that the sub-region has been traversed by the mobile platform M, and the other sub-regions are marked as 0, indicating the sub-area that the mobile platform M has not traversed, and then updating the sub-area information in the virtual map and storing it.

S103: Determine a target sub-area from the untraversed sub-areas adjacent to the traversed area.

The adjacent sub-area refers to a sub-area that the mobile platform can reach from the traversed area without going through the third sub-area.

As shown in Fig. 4, since the sub-areas in the virtual map are square, and the sub-areas connected to the traversed area include four, the four sub-areas are regarded as adjacent sub-areas of the traversed area, and they are marked as B. Wherein, the adjacent sub-region refers to a sub-region that the mobile platform M can reach from the traversed region without going through the third sub-region, that is, a sub-region having a common edge with the traversed region, and having a common vertex Subregions are not counted as adjacent subregions. Then, any one of the four adjacent sub-regions marked as B is used as the target sub-region, and as shown in FIG. 5, the sub-region below the traversed region is marked as A, that is, the target sub-region. Then update the sub-area information of the virtual map and store it.

S104: Move the mobile platform from the traversed area to the target sub-area.

After the virtual map marks the target sub-area A, the mobile platform M moves to the target sub-area A marked in the virtual map.

S105: after the mobile platform reaches a certain target sub-area, mark the sub-area corresponding to the current position of the mobile platform as having traversed the sub-area, and determine a target sub-area from the un-traversed sub-area adjacent to the traversed area. .

FIG. 6 is a schematic diagram of the mobile platform M in an actual situation to reach another position of the unknown area, that is, a position corresponding to the target sub-area A in the virtual map in FIG. 5. Since there is no obstacle in the position of the actual situation in the target sub-area A in FIG. 5, the mobile platform M can smoothly reach the sub-area corresponding to the target sub-area A. After the mobile platform M reaches the sub-area, as shown in FIG. 7, the sub-area is marked as 1, that is, the sub-area has been traversed, and the other three sub-areas that are not traversed adjacent to the sub-area are marked as B. There are 6 adjacent sub-areas. As shown in FIG. 8, one of the six adjacent sub-regions labeled B is arbitrarily selected as A, that is, the target sub-region. Then update the map sub-area information and store it. S106: It is determined whether the target sub-area exists in the virtual map. If yes, the process goes to step S104, and if no, the process ends.

As shown in FIG. 6, the mark in the virtual map shown in FIG. 8 has an obstacle in the target sub-area, and therefore, the mobile platform M cannot enter the area. In this case, the method further includes: When the mobile platform detects an obstacle in the process of moving to the target sub-area, the target sub-area is marked as an obstacle sub-area, and the process returns to step S103.

When the moving platform M in practice moves to the area corresponding to the target sub-area labeled A in FIG. 8, an obstacle is detected, and as shown in FIG. 9, the target sub-area marked A is re-marked as 2, that is, The obstacle sub-area is arbitrarily selected from the other six adjacent sub-areas labeled A, that is, as the target sub-area, and then the map sub-area information is updated and stored. So repeatedly, until the sub-region has been traversed, there is no target sub-region, FIG. 10 shows a schematic diagram of the mobile platform M after the traversal of the unknown region is completed, and FIG. 11 shows a schematic diagram of the mobile platform M in the virtual map after completing the unknown region. .

Embodiment 2

The second embodiment of the present invention provides a method for overlaying a self-built map of a mobile platform in an unknown area, and the implementation process is the same as that of the embodiment. Different from the first embodiment, in the first embodiment, as shown in FIG. 2, the size of the sub-area in the virtual map is substantially the same as the size of the mobile platform in the virtual map, and in the second embodiment, as shown in FIG. The size of the sub-area in the virtual map is about 1/2 of the size of the mobile platform in the virtual map.

In the following description of the specific steps of the second embodiment, the focus is on the difference from the first embodiment, and the same can be found in the first embodiment.

S102: Mark the sub-area corresponding to the current position of the mobile platform in the virtual map as the traversed sub-area, and mark the other sub-areas as not traversing the sub-area.

As shown in FIG. 13, the mobile platform M initially occupies 4 sub-areas, so the four sub-areas corresponding to the area occupied by the mobile platform M in the virtual map are marked as 1, that is, the sub-areas have been traversed.

S103: Determine a target sub-area from an untraversed sub-area adjacent to the traversed area, where the adjacent sub-area refers to a sub-area that the mobile platform can reach from the traversed area without passing through the third sub-area. As shown in FIG. 14, the number of untraversed sub-regions adjacent to the traversed region includes eight, as shown in FIG. As shown, one sub-region is selected as the target sub-region from the un-traversed sub-region adjacent to the traversed region. For example, the sub-region on the right side of the traversed region may be marked as Α, that is, the target sub-region.

S104: Move the mobile platform from the traversed area to the target sub-area. In the middle, it is detected that there is an obstacle on the left side of the moving direction. Therefore, the two adjacent sub-areas with obstacles are marked as 2, that is, the obstacle sub-area.

S105: After the mobile platform reaches a certain target sub-area, mark an area in the virtual map corresponding to the current position of the mobile platform as the traversed area, and determine a target from the untraversed sub-area adjacent to the traversed area. Sub-area.

As shown in Fig. 16, it is a schematic diagram of the mobile platform 另外 under actual conditions until another position of the unknown area is reached, which corresponds to the target sub-area 中 in the virtual map in Fig. 15. Since the mobile platform M can successfully reach the sub-area. After the mobile platform M reaches the sub-area, as shown in FIG. 17, the sub-area and its left sub-area are both marked as 1, that is, the sub-area has been traversed, and the sub-area is adjacent to the left sub-area thereof. The other 4 sub-regions that are not traversed are marked as B, and there are 8 adjacent sub-regions (two have been marked as obstacle sub-regions). As shown in Fig. 18, one of the eight adjacent sub-areas labeled B is arbitrarily selected as A, that is, the target sub-area. The area information of the virtual map sub is then updated and stored.

S106: It is judged whether the target sub-area exists in the virtual map, and if yes, the process goes to step S104, otherwise, the process ends.

As shown in FIG. 15, in the actual situation, although there is no obstacle in the area corresponding to the target sub-area marked A in the virtual map shown in FIG. 17, the size of the mobile platform in the virtual map is approximately virtual. The size of the sub-area in the map is twice as large, and therefore, when there is an obstacle in the area corresponding to the sub-area to the left of the target sub-area, the mobile platform M cannot enter the area.

The above method may further include: if the mobile platform detects an obstacle during the movement to the target sub-area, marking the target sub-area as an obstacle sub-area, and returning to step S103.

As shown in Fig. 19, the sub-area on the left side of the target sub-area A is marked as 2, that is, the obstacle sub-area, and then the map sub-area information is updated and stored.

The above method may further include: if the mobile platform cannot reach a certain target through the traversed area In the area, the target sub-area is marked as an obstacle sub-area, and the process returns to step S103. As shown in FIG. 19, since the mobile platform M cannot enter the target sub-area A as in 18 through the sub-region that has been traversed, it is also marked as 2, that is, the obstacle area, and then the mobile platform M is moved from the remaining 6 One of the adjacent sub-regions is selected as the target sub-region, and the process returns to step S103.

This is repeated until there is no target sub-area that has been traversed in the sub-area, as shown in Figure 20, the mobile platform

The schematic diagram of M after the traversal of the unknown region is completed, as shown in FIG. 21, is a schematic diagram of the mobile platform M in the virtual map after completing the unknown region.

As shown in FIG. 22, the side length of the square sub-area in the virtual map is about twice the diameter of the mobile platform M in the virtual map. Therefore, in theory, the mobile platform M can be marked from the arrow in the figure. The direction is past and covers part of the area. In the traversal process of the actual mobile platform, since the two sub-areas in the virtual map are marked as obstacle areas after the obstacles of the two sub-areas are detected on the mobile platform, the mobile platform M does not It will enter the position corresponding to the two sub-areas of the virtual map, so that there are some areas that can be covered theoretically but cannot be covered, so the division of the sub-areas should not be too large.

As shown in FIG. 23, the side length of the square sub-area in the virtual map is less than or equal to 1/2 of the diameter of the mobile platform M in the virtual map. Therefore, in FIG. 23, the mobile platform M cannot theoretically be from two. The sub-areas with obstacles pass in the direction indicated by the arrow. Theoretically, if the storage system supports, the recommended sub-area is as small as possible, so that the mobile platform M can cover the unknown area as much as possible. If the sub-area is an irregular figure and the mobile platform M is non-circular, the diameter of the smallest coverage circle that can be expressed as a sub-area in the virtual map is less than or equal to the minimum width of the mobile platform in the map storage system. 1/2, where the minimum coverage circle refers to a circle whose diameter is the two end points of the farthest distance apart from the edge of the sub-area, and the minimum width refers to the width of the space through which the mobile platform can pass.

As shown in FIG. 24, it is a schematic diagram of all the sub-regions in the virtual map in the map storage system are regular hexagons of the same size, which can cover the entire virtual map in six directions, and the adjacent regions of the single sub-region have 6 The method and the steps for covering the mobile platform M in the sub-region of the regular hexagon are the same as those in the first embodiment and the second embodiment, and therefore will not be described again.

Embodiment 3

Embodiment 3 of the present invention provides a coverage system for a self-built map of a mobile platform in an unknown area. These include: drive systems, relative positioning systems, map storage systems, and control systems. Where: the drive system is used to drive the displacement of the mobile platform.

The relative positioning system is used to determine the relative position of the area where the mobile platform is located after the movement relative to the area before the movement.

A map storage system for marking a pre-stored sub-area in a virtual map centered on a starting point and including a plurality of sub-areas as a traversed area.

a control system, configured to: when the mobile platform enters an unknown area, control the map storage subsystem to correspond the starting point of the pre-stored virtual map with the current location of the mobile platform, and control the current location of the map storage subsystem in the virtual map and the mobile platform The sub-region corresponding to the location is marked as having traversed the sub-region, and the other sub-regions in the virtual map are marked as untraversed sub-regions, and a target sub-region is determined from the un-traversed sub-region adjacent to the traversed region; using the relative locator a system determined position, the control drive subsystem moves the mobile platform into an area corresponding to the target sub-area; the control map storage subsystem marks the sub-area corresponding to the current position of the mobile platform in the virtual map as having traversed the sub-area, and Determining a target sub-area from an un-traversed sub-area adjacent to the traversed area. The control system uses the relative positioning system to control the drive system and the map storage system to repeatedly perform the above operations until there is no target sub-area in the virtual map.

The system provided by the embodiment of the present invention may further include: a fault detection system for detecting a fault. When the obstacle is detected, the control system controls the map storage system to mark the target sub-area as the obstacle sub-area.

The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments are obvious to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not intended to be limited to the embodiments shown herein, but is to be accorded to the broadest scope consistent with the principles and novel features disclosed herein.

Claims

Rights request

1. A coverage method for a mobile platform to self-build a map in an unknown area, which is characterized by pre-establishing a virtual map centered on the starting point and including multiple sub-areas. The method includes: (1) When the mobile platform When entering an unknown area, correspond the current position of the mobile platform to the sub-area where the starting point of the virtual map is located;

(2) Mark the sub-area in the virtual map corresponding to the current position of the mobile platform as a traversed sub-area, and mark other sub-areas in the virtual map as un-traversed sub-areas; (4) Mark The mobile platform moves to the area corresponding to the target sub-area;

(5) Mark the sub-area in the virtual map corresponding to the current position of the mobile platform as a traversed sub-area, and determine a target sub-area from the un-traversed sub-areas adjacent to the traversed area;

(6) Repeat steps (4) to (5) until there is no target sub-area in the virtual map.

2. The method according to claim 1, further comprising: if an obstacle is detected, marking the target sub-region as an obstacle sub-region, and then returning to step (3).

3. The method according to claim 2, further comprising:

If the mobile platform cannot reach the target sub-area through the traversed area, mark the target sub-area as an obstacle sub-area and return to step (3).

4. The method according to claim 1, characterized in that the diameter of the minimum coverage circle of each sub-area in the pre-established virtual map is less than or equal to 1/2 of the diameter of the mobile platform in the virtual map, wherein , the minimum coverage circle is a circle with the diameter of the two endpoints that are farthest apart from the edges of the sub-region.

5. The method according to claim 1, characterized in that the shape and size of each sub-area in the pre-established virtual map are the same.

6. The method according to claim 1, characterized in that the shape of each sub-area in the pre-established virtual map is a square.

7. The method according to claim 1, characterized in that the shape of each sub-area in the pre-established virtual map is a regular hexagon.