JP7501385B2 - Map data creation method and device - Google Patents

Description

The present invention relates to a map data creation method and device.

As a conventional map data creation device, for example, the technology described in Patent Document 1 is known. The map data creation device described in Patent Document 1 includes a partial map generation unit that generates multiple partial maps by complementing shape data included in environmental information based on the travel trajectory of the autonomous mobile device, and a map generation unit that connects the multiple partial maps generated by the partial map generation unit to generate a map for self-position estimation.

Patent No. 5930346

However, maps created using techniques such as SLAM (simultaneous localization and mapping) are prone to errors. For this reason, if there are overlapping areas between adjacent partial maps used in merging, there is a concern that lines in the map may become thicker or doubled after the adjacent partial maps are merged. For example, when estimating the self-position of a moving object by matching detection data from a laser sensor with map data for self-position estimation, if lines in the map become thicker or doubled, the matching range becomes larger, leading to a decrease in the accuracy of the self-position estimation.

The object of the present invention is to provide a method and device for creating map data that can optimize lines within a map.

A map data creation method according to one aspect of the present invention includes a partial map creation step of creating partial maps of multiple areas using a laser detection unit that detects objects around the moving body by irradiating a laser around the moving body, a positioning step of aligning the partial maps of the multiple areas created in the partial map creation step, a use area designation step of designating a use area of the partial maps of the multiple areas after the positioning step is performed, and a partial map synthesis step of synthesizing the partial maps of the multiple areas after the use area designation step is performed, in which the positioning step aligns the partial maps of the multiple areas so that the ends of the partial maps of adjacent areas overlap each other, the use area designation step designates the use areas of the partial maps of the multiple areas so that the partial maps of adjacent areas do not overlap each other, and the partial map synthesis step combines the partial maps of the multiple areas by connecting the use areas of the partial maps of adjacent areas.

In such a map data creation method, first, partial maps of multiple areas are created using a laser detection unit that irradiates a laser around a moving body to detect objects present around the moving body. Then, after the partial maps of multiple areas are aligned, the use areas of the partial maps of multiple areas are specified, and the partial maps of multiple areas are combined. As a result, map data consisting of partial maps of multiple areas is formed. Here, the partial maps of multiple areas are aligned so that the ends of the partial maps of adjacent areas overlap each other, and the use areas of the partial maps of multiple areas are specified so that the partial maps of adjacent areas do not overlap each other. Then, the use areas of the partial maps of adjacent areas are connected, and the partial maps of multiple areas are combined. Therefore, after the partial maps of multiple areas are combined, the lines in the map are prevented from becoming thicker or doubled. This optimizes the lines in the map.

In the use area designation process, the use area may be designated so that a position inside the edge of the partial map in the overlapping portion of the partial maps of adjacent areas becomes the boundary position of the use area of the partial maps of the adjacent areas.

When a moving body equipped with a laser detection unit creates partial maps of multiple areas using the laser detection unit while traveling, the moving body may be far from the object as long as the laser detection unit can detect the object around the moving body. However, the longer the distance from the laser detection unit to the object, the lower the accuracy of object detection by the laser detection unit. Therefore, by specifying the use area so that a position inside the edge of the partial map in the overlapping portion of the partial maps of adjacent areas becomes the boundary position of the use area of the partial maps of adjacent areas, the moving body does not need to travel close to a position on the object that corresponds to the edge of the partial map in order to increase the accuracy of object detection by the laser detection unit. Therefore, the accuracy of object detection by the laser detection unit can be increased while shortening the travel distance of the moving body.

In the use area designation process, the use area may be designated so that the midpoint of the overlapping portion of the partial maps of adjacent areas becomes the boundary position of the use area of the partial maps of adjacent areas.

In this case, the distance from the edge of the partial map of adjacent areas to the boundary position of the used area of the partial map of each adjacent area is equal. This makes it possible to further shorten the travel distance of the moving body or further increase the accuracy of object detection by the laser detection unit. Therefore, map data can be created efficiently.

A map data creation device according to another aspect of the present invention includes a partial map acquisition unit that acquires partial maps of multiple areas created using a laser detection unit that detects objects present around the moving body by irradiating a laser around the moving body, an alignment processing unit that aligns the partial maps of multiple areas acquired by the partial map acquisition unit, and a partial map synthesis unit that synthesizes the partial maps of multiple areas after the alignment processing unit aligns the partial maps of multiple areas, the alignment processing unit aligns the partial maps of multiple areas so that the ends of the partial maps of adjacent areas overlap each other, and the partial map synthesis unit synthesizes the partial maps of multiple areas by connecting the use areas of the partial maps of adjacent areas with the use areas of the partial maps of multiple areas specified so that the partial maps of adjacent areas do not overlap each other.

In such a map data creation device, first, partial maps of multiple areas are created using a laser detection unit that irradiates a laser around the moving body to detect objects present around the moving body. Then, after the partial maps of multiple areas are aligned, the partial maps of multiple areas are synthesized. As a result, map data consisting of partial maps of multiple areas is formed. Here, the partial maps of multiple areas are aligned so that the ends of the partial maps of adjacent areas overlap each other. Then, with the use areas of the partial maps of multiple areas specified so that the partial maps of adjacent areas do not overlap each other, the use areas of the partial maps of adjacent areas are connected to synthesize the partial maps of multiple areas. Therefore, after the partial maps of multiple areas are synthesized, the lines in the map are prevented from becoming thicker or doubled. This optimizes the lines in the map.

The present invention allows for the optimization of lines within a map.

1 is a schematic configuration diagram showing a driving control device to which a map data creation method and device according to an embodiment of the present invention is applied; FIG. 2 is a plan view showing an example of a travel area in which a moving object travels. 4 is a flowchart showing steps of a map data creation method according to an embodiment of the present invention. FIG. 11 is a plan view showing an example of aligning partial maps of multiple areas. FIG. 13 is a plan view showing an example in which partial maps of a plurality of areas are combined by specifying areas to be used. 1 is a schematic configuration diagram showing a map data creation device according to an embodiment of the present invention;

The following describes an embodiment of the present invention in detail with reference to the drawings.

Figure 1 is a schematic diagram showing a driving control device to which a map data creation method and device according to one embodiment of the present invention is applied. In Figure 1, the driving control device 1 is mounted on a mobile object 2 such as a forklift (see Figure 2).

The driving control device 1 is a device that causes a mobile object 2 to drive autonomously. In this example, the mobile object 2 drives along shelves 3 that are installed in multiple rows in a warehouse or the like, as shown in FIG. 2. The driving control device 1 includes a laser sensor 4, a map data storage unit 5, a controller 6, and a drive unit 7.

As shown in FIG. 2, the laser sensor 4 is a laser detection unit that detects shelves 3, which are objects present around the mobile unit 2, by irradiating a laser L around the mobile unit 2 and receiving the reflected light of the laser L, thereby acquiring point cloud data. As the laser sensor 4, for example, a laser range finder is used.

The map data storage unit 5 stores map data (see FIG. 5(b)) of the driving area in which the mobile unit 2 drives. The map data is used to estimate the self-position of the mobile unit 2.

The controller 6 is composed of a CPU, RAM, ROM, an input/output interface, etc. The controller 6 has a self-position estimation unit 8 and a driving control unit 9.

The self-position estimation unit 8 estimates the self-position of the mobile unit 2 based on the detection data (point cloud data) of the laser sensor 4 and the map data stored in the map data storage unit 5. The self-position estimation unit 8 performs an estimation calculation of the self-position of the mobile unit 2 using a laser SLAM (simultaneous localization and mapping) method. SLAM is a self-position estimation technology that performs self-position estimation using sensor data and map data. The self-position estimation unit 8 matches the detection data of the laser sensor 4 with the map data to perform an estimation calculation of the self-position of the mobile unit 2.

The driving control unit 9 controls the drive unit 7 to drive the mobile unit 2 to the destination based on the self-position of the mobile unit 2 estimated by the self-position estimation unit 8. The drive unit 7 has, for example, a travel motor and a steering motor.

Figure 3 is a flowchart showing the steps of a map data creation method according to one embodiment of the present invention.

In FIG. 3, first, a partial map creation step is carried out using the above-mentioned laser sensor 4 to create partial maps of multiple areas in which the mobile unit 2 travels (step S101). At this time, partial maps of multiple areas are created while the mobile unit 2 travels. For example, in the travel area shown in FIG. 2, partial maps Ma to Mc of three areas A to C are created, as shown in FIG. 4(a).

Next, an alignment process is carried out to align the partial maps of multiple areas created in the partial map creation process (process S102). Although the partial maps of each area have independent coordinate systems, by carrying out the alignment process, the coordinate systems of the partial maps of each area can be made to match. In the alignment process, the partial maps of each area are aligned so that the ends of the partial maps of adjacent areas overlap each other.

In the travel area shown in FIG. 2, the partial maps Ma and Mb are aligned so that the ends of the partial maps Ma and Mb of adjacent areas A and B overlap each other, as shown in FIG. 4(b). Also, the partial maps Mb and Mc are aligned so that the ends of the partial maps Mb and Mc of adjacent areas B and C overlap each other.

After the alignment process is performed, a use area designation process is performed in which the use areas of the partial maps of multiple areas are designated (step S103). In the use area designation process, the use areas are designated so that the partial maps of adjacent areas do not overlap with each other. The use area is an area that is used as part of the map data in the partial map.

At this time, the area of use is specified so that the position inside the edge of the partial map in the overlapping portion of the partial maps of adjacent areas becomes the boundary position of the area of use of the partial maps of adjacent areas. Specifically, the area of use is specified so that the middle position of the overlapping portion of the partial maps of adjacent areas becomes the boundary position of the area of use of the partial maps of adjacent areas. The boundary position is the position where the area of use of the partial maps of adjacent areas is connected.

In the driving area shown in Figure 2, as shown in Figures 4(b) and 5(a), the use areas Ua and Ub are specified so that the midpoint of the overlapping portion Jab of the partial maps Ma and Mb of adjacent areas A and B becomes the boundary position Kab of the use areas Ua and Ub of the partial maps Ma and Mb. Therefore, the distance from the edge Ea of the partial map Ma to the boundary position Kab is equal to the distance from the edge Eb1 of the partial map Mb to the boundary position Kab.

The use areas Ub and Uc are specified so that the midpoint of the overlapping portion Jbc of the partial maps Mb and Mc of the adjacent areas B and C becomes the boundary position Kbc of the use areas Ub and Uc of the partial maps Mb and Mc. Therefore, the distance from the edge Eb2 of the partial map Mb to the boundary position Kbc is equal to the distance from the edge Ec of the partial map Mc to the boundary position Kbc. Note that the edge Eb2 of the partial map Mb is the edge opposite the edge Eb1 of the partial map Mb.

After the area-of-use designation step is performed, a partial map synthesis step is performed to synthesize partial maps of multiple areas (step S104). In the partial map synthesis step, the partial maps of each area are synthesized by connecting the areas of use of the partial maps of adjacent areas. This forms one piece of map data consisting of partial maps of multiple areas.

In the driving area shown in FIG. 2, as shown in FIG. 5(a) and FIG. 5(b), the partial maps Ma to Mc of areas A to C are combined by connecting the use areas Ua and Ub of the partial maps Ma and Mb of adjacent areas A and B, and connecting the use areas Ub and Uc of the partial maps Mb and Mc of adjacent areas B and C. This results in map data M consisting of the partial maps Ma to Mc.

Figure 6 is a schematic diagram showing a map data creation device according to one embodiment of the present invention. In Figure 6, the map data creation device 10 of this embodiment is a device that implements the map data creation method described above.

The map data creation device 10 includes a partial map storage unit 11 and a personal computer (PC) 12 used by a user. The map data storage unit 5 is connected to the PC 12.

The partial map storage unit 11 stores partial maps of multiple areas created in the partial map creation process described above.

The personal computer 12 has an input unit 13 that allows the user to input data and information, a display unit 14 that displays the data and information, and a PC main body 15 that performs calculations based on the data and information input by the input unit 13 and displays the data and information on the display unit 14.

The PC main body 15 is composed of a CPU, RAM, ROM, an input/output interface, etc. The PC main body 15 has a partial map acquisition unit 16, a position alignment processing unit 17, a partial map synthesis unit 18, and a map data storage unit 19.

When an instruction to acquire a partial map is input by the input unit 13, the partial map acquisition unit 16 acquires partial maps of multiple areas stored in the partial map storage unit 11 and displays the partial map of each area on the display unit 14. In other words, the partial map acquisition unit 16 acquires partial maps of multiple areas created using the laser sensor 4.

The alignment processing unit 17 aligns the partial maps of multiple areas acquired by the partial map acquisition unit 16. The alignment processing unit 17 aligns the partial maps of each area so that the ends of the partial maps of adjacent areas overlap each other. The alignment processing unit 17 cooperates with the partial map acquisition unit 16 to carry out the above alignment process.

When the alignment processing unit 17 aligns the partial maps of each area, the user, while looking at the display unit 14, specifies and inputs the area to be used of the partial map of each area using the input unit 13. In other words, the above-mentioned area to be used designation process is performed by the user.

After the user has specified the area to be used of the partial map of each area, the partial map synthesis unit 18 synthesizes the partial maps of each area. This provides map data to be used for estimating the self-position of the mobile unit 2. The partial map synthesis unit 18 connects the areas to be used of the partial maps of adjacent areas, with the areas to be used of the partial maps of each area specified so that the partial maps of adjacent areas do not overlap each other. The partial map synthesis unit 18 carries out the partial map synthesis process described above.

The map data storage unit 19 stores the map data obtained by the partial map synthesis unit 18 in the map data memory unit 5.

As described above, in this embodiment, first, a partial map of a plurality of areas is created using a laser sensor 4 that irradiates a laser L around the mobile body 2 to detect shelves 3 around the mobile body 2. Then, after the partial maps of the plurality of areas are aligned, the use areas of the partial maps of the plurality of areas are designated, and the partial maps of the plurality of areas are combined. As a result, map data consisting of partial maps of the plurality of areas is formed. Here, the partial maps of the plurality of areas are aligned so that the ends of the partial maps of adjacent areas overlap each other, and the use areas of the partial maps of the plurality of areas are designated so that the ends of the partial maps of adjacent areas do not overlap. Then, the use areas of the partial maps of adjacent areas are connected to combine the partial maps of the plurality of areas. Therefore, after the partial maps of the plurality of areas are combined, the lines in the map are prevented from becoming thicker or doubled. This optimizes the lines in the map. As a result, the increase in the matching range between the detection data of the laser sensor 4 and the map data is suppressed, and the estimation accuracy of the self-position of the mobile body 2 is improved.

When creating partial maps of multiple areas using the laser sensor 4 while the mobile object 2 is traveling, the mobile object 2 may be away from the shelves 3 as long as the laser sensor 4 can detect the shelves 3 around the mobile object 2. In this case, the mobile object 2 does not have to travel close to the shelves 3, so the travel distance of the mobile object 2 is shortened. However, the longer the distance from the laser sensor 4 to the shelves 3, the lower the accuracy of detection of the shelves 3 by the laser sensor 4.

On the other hand, in this embodiment, the use area is specified so that a position inside the edge of the partial map in the overlapping portion of the partial maps of adjacent areas becomes the boundary position of the use area of the partial map of the adjacent area. Therefore, in order to increase the detection accuracy of the shelf 3 by the laser sensor 4, the mobile body 2 does not need to travel close to a position on the shelf 3 that corresponds to the edge of the partial map. Therefore, it is possible to increase the detection accuracy of the shelf 3 by the laser sensor 4 while shortening the travel distance of the mobile body 2.

In addition, in this embodiment, the use area is specified so that the midpoint of the overlapping portion of the partial maps of adjacent areas is the boundary position of the use area of the partial maps of adjacent areas, so the distance from the edge of the partial maps of adjacent areas to the boundary position of the use area of the partial maps of each adjacent area is equal. This makes it possible to further shorten the travel distance of the mobile body 2, or further increase the detection accuracy of the shelf 3 by the laser sensor 4. Therefore, map data can be created efficiently.

The present invention is not limited to the above embodiment. For example, in the above embodiment, the use areas of the partial maps of multiple areas are specified by the user, but the present invention is not limited to such an embodiment. For example, the use areas of the partial maps of multiple areas may be automatically specified by the system by providing CAD data of objects such as shelves and buildings to a personal computer.

In addition, in the above embodiment, the use area designation process is performed by the user, and the alignment process and partial map synthesis process are performed automatically by the system, but this is not a particular limitation, and the alignment process and partial map synthesis process may also be performed by the user.

In addition, in the above embodiment, the use area is specified so that the midpoint of the overlapping portion of the partial maps of adjacent areas is the boundary position of the use area of the partial maps of adjacent areas, but the boundary position of the use area of the partial maps of adjacent areas is not limited to this and may be any overlapping portion of the partial maps of adjacent areas.

In addition, locations where there is little point cloud data from the laser sensor 4 (e.g. locations corresponding to driving roads, etc.) may be set as boundary positions of the usage areas of partial maps of adjacent areas.

In addition, in the above embodiment, after the self-position of the moving body 2 is estimated, the moving body 2 is controlled to perform autonomous driving, but the present invention can be applied to things other than the self-position estimation and autonomous driving of the moving body 2.

2...mobile body, 3...shelf (object), 4...laser sensor (laser detection unit), 10...map data creation device, 16...partial map acquisition unit, 17...alignment processing unit, 18...partial map synthesis unit, A to C...area, Ma to Mc...partial map, M...map data, Jab, Jbc...overlapping portion, Kab, Kbc...boundary position, Ea, Eb1, Eb2, Ec...edge.

Claims (2)

a partial map creation step of creating partial maps of a plurality of areas using a laser detection unit that irradiates a laser around a moving object to detect objects present around the moving object and acquires point cloud data ;
a registration step of registering the partial maps of the plurality of areas created using the laser detection unit in the partial map creation step;
a use area designation step of designating use areas of the partial maps of the plurality of areas after the positioning step is performed;
a partial map synthesis step of synthesizing partial maps of the plurality of areas after the use area designation step is performed,
In the positioning step, the partial maps of the plurality of areas are positioned based on the point cloud data of the partial maps of the plurality of areas such that ends of the partial maps of adjacent areas overlap each other and coordinate systems of the partial maps of the adjacent areas match;
the use area designation step includes designating use areas of the partial maps of the plurality of areas such that a middle position of an overlapping portion of the partial maps of the adjacent areas becomes a boundary position of the use areas of the partial maps of the adjacent areas;
In the partial map synthesis step, the partial maps of the plurality of areas are synthesized by connecting the used areas of the partial maps of the adjacent areas. a partial map acquisition unit that acquires partial maps of a plurality of areas created using a laser detection unit that irradiates a laser around a moving object to detect objects present around the moving object and acquires point cloud data ;
a registration processing unit that performs registration of the partial maps of the plurality of areas acquired by the partial map acquisition unit;
a partial map synthesis unit that synthesizes the partial maps of the plurality of areas after the alignment processing unit aligns the partial maps of the plurality of areas,
the registration processing unit aligns the partial maps of the plurality of areas using point cloud data of the partial maps of the plurality of areas such that ends of the partial maps of adjacent areas overlap with each other and coordinate systems of the partial maps of the adjacent areas match;
The partial map synthesis unit synthesizes the partial maps of the multiple areas by connecting the used areas of the partial maps of the adjacent areas, with the used areas of the partial maps of the multiple areas being specified so that the intermediate positions of the partial maps of the adjacent areas become the boundary positions of the used areas of the partial maps of the adjacent areas.

Images