JP7243141B2 - Movement route generation device, movement route generation method, and computer program - Google Patents

Description

The present invention relates to a travel route generation device, a travel route generation method, and a computer program.

Conventionally, there has been known a travel route generation device that uses map information to create a travel route from the current location of an autonomous mobile body to a destination. The movement route generation device generates an optimal movement route based on movement costs such as time and energy required for movement from the current location to the destination. For example, in Patent Document 1, there is a device that generates a moving route of an autonomous mobile body that moves with a human on it, and in addition to the moving distance of the autonomous mobile body, the visibility from the autonomous mobile body is empirically A technique for generating a moving route based on the degree of sense of security obtained is disclosed. In addition, Patent Document 2 discloses a technique for setting a plurality of nodes on the movement route of an autonomous mobile body and sequentially selecting a movement route that minimizes the movement cost when moving directly from the current location to the plurality of nodes. It is

JP 2016-218880 A Japanese Unexamined Patent Application Publication No. 2005-50105

The moving route generation device described in Patent Literature 1 assumes that there is a passenger on the autonomous mobile body, so it generates a moving route that gives the passenger a sense of security. However, if priority is given to the passenger's sense of security, a movement route with poor environmental features for estimating the position of the autonomous mobile body may be set, and there is a risk that the estimation error of the current location of the autonomous mobile body will increase.
Further, the travel route generation device described in Patent Document 2 includes environment recognition means for estimating obstacles and the current location of the device itself. However, if there is a space with poor environmental features for estimating one's current location on the movement route that minimizes the movement cost, the error in estimating one's current location increases, and there is a risk that one will lose sight of one's current location and become unable to move. Also, even if the autonomous mobile body reaches the destination, if the error at the destination is large, there is a risk that the next operation of the autonomous mobile body will be affected.

The present invention has been made to solve the above-described problems, and is a movement route generation device that generates a movement route from the current location of an autonomous mobile body to a destination, in which the autonomous mobile body reaches the destination with high accuracy. The purpose is to provide technology to

The present invention has been made to solve at least part of the above problems, and can be implemented as the following modes.

(1) According to one aspect of the present invention, there is provided a movement route generation device that generates a movement route from the current location of an autonomous mobile body to a destination. The movement route generation device includes a map information storage unit that stores map information including information about landmarks for estimating the position of the autonomous mobile body, and a map information storage unit that uses the map information to determine the destination from the current location of the autonomous mobile body. An observable area estimation unit that estimates an observable area in which the landmark can be observed from a distance to the ground, and a moving route generating unit that generates the moving route using the estimated observable area.

According to this configuration, the moving route generator generates the moving route using the observable area where the landmarks can be observed, which is estimated by the observable area estimator. When the movement route of the autonomous mobile body is generated so as to preferentially pass through the observable area, the autonomous mobile body moving on the movement route reliably observes the landmarks for estimating its own current location. be able to. As a result, the accuracy of estimating the current location of the autonomous mobile body can be improved, and the error at the destination can be reduced because the destination can be reached without losing sight of the current location. Therefore, the autonomous mobile body can reach the destination with high accuracy.

(2) The movement route generation device of the above aspect further includes an environment recognition sensor that is arranged on the autonomous mobile body and acquires external environment information for recognizing the external environment of the autonomous mobile body, and the movement route generation device The unit may set a direction in which the environment recognition sensor acquires the external environment information to a direction in which the landmark can be observed. According to this configuration, in addition to generating the movement route, the movement route generation unit determines the direction in which the environment recognition sensor arranged on the autonomous mobile body that moves on the movement route acquires the external environment information from the landmark. Set the observable direction. As a result, the environment recognition sensor of the autonomous mobile body moving on the movement route can more reliably detect the landmark, so that the estimation error of the current location of the autonomous mobile body can be further reduced.

(3) The movement route generation device of the above aspect further includes a landmark detection unit that detects information about the landmarks included in the external environment information, information about the landmarks detected by the landmark detection unit, and a current location estimation unit that estimates the current location of the autonomous mobile body by collating it with information related to landmarks included in the map information; You may generate|occur|produce the movement path|route to. According to this configuration, since the positional accuracy of the current location, which is the starting point of the movement route, is improved, the autonomous mobile body can reach the destination more reliably and with higher accuracy.

(4) The movement path generation device of the above aspect further includes an obstacle detection unit that detects information about a moving obstacle included in the external environment information, and an obstacle detection unit that uses the detected information about the moving obstacle to and an obstacle position prediction unit that predicts a position change of an obstacle, wherein the observable area estimation unit uses the position change prediction of the moving obstacle by the obstacle position prediction unit to predict the environment recognition sensor and estimating a shielded area in which information about the landmark is not included in the external environment information acquired by the environment recognition sensor due to the position of the moving obstacle between the landmark and the shielded area from the observable area; Areas may be excluded. According to this configuration, the observable area estimating unit excludes, from the observable area, a shielded area in which information about landmarks is not included in the external environment information acquired by the environment recognition sensor. It is possible to prevent the environment recognition sensor of the mobile from losing sight of the current location due to the inability to detect the landmark. Thereby, an autonomous mobile body can reach a destination more certainly.

(5) In the movement path generation device of the above aspect, the movement path generation unit determines the number of landmarks observable from the autonomous mobile body and the distribution of the landmarks within the field of view observable from the autonomous mobile body. a state, a ratio of the commonly observable landmarks in a plurality of observations from the autonomous mobile body at predetermined time intervals, and the external environment information obtained by the environment recognition sensor at predetermined time intervals. The moving route may be generated using at least one of the acquired direction change amount. According to this configuration, the movement route generation unit can generate a movement route using at least one of these four items related to the ease of recognition of landmarks, so that the autonomous mobile body is more It is possible to reach the destination reliably and with higher accuracy.

(6) The movement route generation device of the above aspect further includes landmark selection for estimating the degree of contribution of the landmark to position estimation of the autonomous mobile body using the information about the landmark included in the map information. The observable area estimating unit may estimate an observable area of only the landmarks having the high contribution or an observable area reflecting the weight of the contribution. According to this configuration, the landmark selection unit selects a landmark according to the degree of contribution to position estimation of the autonomous mobile body, and the observable area estimation unit selects the observable area of the selected landmark to estimate As a result, the observable area estimating unit estimates the observable area for landmarks with a high degree of contribution to position estimation of the autonomous mobile body instead of estimating the observable area for all landmarks. A moving route can be generated in a short amount of time and with little effort. Therefore, it is possible to improve the efficiency and speed of the travel route generation process in the travel route generation device.

It should be noted that the present invention can be implemented in various aspects, for example, a moving route generation method, a moving route generating system, a computer program that causes a computer to generate a moving route, and a server for distributing computer programs. It can be realized in the form of a device, a non-transitory storage medium storing a computer program, or the like.

BRIEF DESCRIPTION OF THE DRAWINGS It is explanatory drawing which showed schematic structure of the movement path|route generation apparatus of 1st Embodiment. 4 is a flow chart of a moving route generation method according to the first embodiment; FIG. 4 is a schematic diagram of a space in which a moving route is generated in the first embodiment; It is a schematic diagram of the observable area estimated in 1st Embodiment. 4 is a schematic diagram of an observable area map generated in the first embodiment; FIG. FIG. 3 is a schematic diagram showing a moving route generated in the first embodiment; FIG. FIG. 4 is a schematic diagram showing directions in which an environment recognition sensor set in the first embodiment is directed; FIG. 5 is a schematic diagram showing a moving route generated by a moving route generating method of a comparative example; It is an explanatory view showing a schematic structure of a moving route generation device of a second embodiment. It is a flow chart of the moving route generation method of the second embodiment. FIG. 11 is a schematic diagram showing a moving trajectory of a moving obstacle in the second embodiment; FIG. 11 is a schematic diagram showing a movement locus of another moving obstacle in the second embodiment; FIG. 11 is a schematic diagram showing a moving route generated in the second embodiment; FIG.

<First embodiment>
FIG. 1 is an explanatory diagram showing a schematic configuration of the movement route generation device of the first embodiment. FIG. 2 is a flow chart of the moving route generation method of the first embodiment. FIG. 3 is a schematic diagram of a space in which movement paths are generated in the first embodiment. The moving route generation device 1 of the first embodiment is a device that generates a moving route from the current location to the destination of an autonomous mobile body 5 that moves autonomously. The movement route generation device 1 compares the map information acquired in advance with the external environment information for recognizing the external environment of the autonomous mobile body 5 acquired by the autonomous mobile body 5 on time, and generates a movement route. to generate Examples of the autonomous moving body 5 include an autonomous traveling robot, an autonomous flying drone, and the like, which have means for recognizing their own external environment. In this embodiment, generation of the movement path of the autonomous robot in a two-dimensional plane by the movement path generation device 1 will be described. may be generated.

The movement route generation device 1 includes a map database 10 , an environment recognition sensor 11 , a landmark detection unit 12 , a current location estimation unit 13 , an observable area map generation unit 14 , and a movement route generation unit 15 . In this embodiment, the movement route generation device 1 is mounted on the autonomous mobile body 5 . However, part or all of the map database 10, the landmark detection unit 12, the current location estimation unit 13, the observable area map generation unit 14, and the moving route generation unit 15, excluding the environment recognition sensor 11, It may be provided outside the autonomous mobile body 5 .

The map database 10 is map information of the space in which the autonomous mobile body 5 moves, and is a collection of data acquired before the movement route is generated by the movement route generation method shown in FIG. The map database 10 stores the positions and shapes of a plurality of landmarks 4 for estimating the position of the autonomous mobile body 5 and obstacles 7 that hinder the movement of the autonomous mobile body 5, as in the map shown in FIG. , information such as presence or absence of movement is stored. Landmarks 4 and obstacles 7 can be stored in association with various levels of features such as image feature points, geometric features, and objects. In this embodiment, information on landmarks 4 and obstacles 7 is associated with image feature points such as SIFT and ORB. can be done. In this embodiment, the map database 10 stores not only the three-dimensional positions of a plurality of landmarks 4 and obstacles 7, but also the positions and orientations of the cameras when the feature points of the landmarks 4 and obstacles 7 are observed. are stored.

In the map of FIG. 3, the autonomous mobile body 5 is indicated by a diamond-shaped figure. That is, in the map of FIG. 3 , the position of the lozenge indicates the current location of the autonomous mobile body 5 . Also, the destination 6 of the autonomous mobile body 5 is indicated by a star having six projections.
In the map of FIG. 3, the landmarks 4 are shown as stars with four projections. In the map of FIG. 3, 22 landmarks 4 from the landmark 4a to the landmark 4v are shown in order of proximity from the current location of the autonomous mobile body 5. In FIG. Obstacles 7 are indicated by rectangles or ellipses. In the schematic diagram shown in FIG. 3, eleven obstacles 7 from obstacle 7a to obstacle 7k are shown. The movement route generation device 1 generates a movement route from the current location of the autonomous mobile body 5 to the destination 6 based on the map shown in FIG.

The environment recognition sensor 11 is arranged in the autonomous mobile body 5 and has a function of acquiring external environment information of the autonomous mobile body 5. For example, it is a camera, a laser range finder, or the like. In this embodiment, the autonomous mobile body 5 is equipped with a camera fixed to the autonomous mobile body 5 itself, and by changing the attitude of the autonomous mobile body 5, the direction in which the camera acquires external environment information can be changed. The environment recognition sensor 11 is provided on the autonomous mobile body 5 via a mechanism that is relatively movable with respect to the autonomous mobile body 5, so that the environment recognition sensor 11 can detect external environment information without changing the posture of the autonomous mobile body 5. may be changed.

The landmark detector 12 is electrically connected to the environment recognition sensor 11 . The landmark detection unit 12 processes the external environment information acquired by the environment recognition sensor 11, and detects the landmarks 4 recognized by the environment recognition sensor 11 from the external environment information.

The current location estimation unit 13 is electrically connected to the landmark detection unit 12 and the map database 10 . The current location estimating unit 13 compares the information about the landmarks detected by the landmark detecting unit 12 with the information about the landmarks in the map information stored in the map database 10, and determines the current location of the autonomous mobile body 5 and the environment. and the orientation of the recognition sensor 11 are estimated.

The observable area map generator 14 is electrically connected to the current location estimator 13 and the map database 10 . The observable area map generator 14 estimates an observable area as an area where the landmarks 4 can be observed on the map stored in the map database 10 . When there are a plurality of landmarks 4 in the map as shown in FIG. 3, the observable area map generation unit 14 estimates observable areas for each of the landmarks 4, and generates an observable area combining the plurality of observable areas. Generate an observation area map. The details of the observable area map generation method in the observable area map generation unit 14 will be described later.

The moving route generator 15 is electrically connected to the observable area map generator 14 . The moving route generation unit 15 uses the observable area map of the observable area map generating unit 14 to generate the moving route of the autonomous mobile body 5 . The details of the movement route generation method in the movement route generation unit 15 will be described later.

Next, a method of generating a movement route of the autonomous mobile body 5 by the movement route generation device 1 will be described. The moving route generation method in the moving route generation device 1 of the present embodiment selects a place where the current location of the autonomous mobile body 5 can be estimated with high accuracy, and generates a moving route that can go to the destination.

First, the map database 10 stores map information along which the autonomous mobile body 5 moves (step S10). The map database 10 stores map information including information on a plurality of landmarks 4 and information on obstacles 7, as described above.

Next, the environment recognition sensor 11 acquires external environment information (step S11). Specifically, the environment recognition sensor 11 captures an image of the external environment of the autonomous mobile body 5 using a camera mounted on the autonomous mobile body 5 and acquires the imaging result as the external environment information of the autonomous mobile body 5 . The environment recognition sensor 11 outputs the imaging result to the landmark detection unit 12 .

Next, the landmark detector 12 detects landmarks 4 from the external environment information (step S12). Specifically, the landmark detection unit 12 detects the landmarks 4 appearing in the imaging result of the environment recognition sensor 11 . The landmark detection unit 12 outputs the detected landmarks 4 to the current location estimation unit 13 .

Next, the current location estimating unit 13 collates the information about the detected landmark 4 with the information about the landmark 4 in the map information to estimate the current location of the autonomous mobile body 5 (step S13). Specifically, the current position estimation unit 13 searches the map information for the same landmark 4 as the landmark 4 detected by the landmark detection unit 12 . When a landmark 4 that matches the landmark 4 detected by the landmark detection unit 12 is found in the map information, the position and characteristic points of the landmark 4 stored in the map database 10 are determined. The position of the autonomous mobile body 5 and the orientation of the environment recognition sensor 11 are estimated from the position and orientation of the camera when observed.

Next, the current location estimation unit 13 acquires destination information (step S14). Specifically, the current location estimating unit 13 stores the destination 6 of the autonomous mobile body 5 that is input to the movement route generation device 1 by an input device (not shown).

Next, the observable area map generator 14 estimates the observable area 8 of the landmark 4 using the map information (step S15). Specifically, the observable area map generation unit 14 uses the map information in which the landmarks 4 in FIG. presume.

FIG. 4 is a schematic diagram of the observable area 8 estimated in this embodiment. For each of the landmarks 4 included in the map information of the map database 10, the visible position and direction are clear from the information obtained when the map is generated.
For example, if the landmark 4 is stored as an image feature point, the appearance of the landmark 4 changes depending on the observation direction. It turns out that the same landmark 4 is observable. It has also been found that given the resolution of the cameras used when generating the map, it is also possible to approximate the distance at which the landmarks 4 are observable. The observable area map generator 14 estimates fan-shaped observable areas 8 shown in FIG.

FIG. 4 shows observable areas 8 of three landmarks 4 d , 4 f and 4 g out of the plurality of landmarks 4 . Specifically, in the landmark 4d, a fan-shaped observable area 8d shown in FIG. 4 is estimated. Similarly, the fan-shaped observable area 8f of FIG. 4 is estimated for the landmark 4f, and the fan-shaped observable area 8g of FIG. 4 is estimated for the landmark 4g.
From the result of the estimated observable area 8 shown in FIG. 4, the autonomous mobile body 5 located in the area where the multiple observable areas 8 overlap each other can observe at least two or more landmarks 4. It can be said. For example, in the observable areas 8d, 8f, and 8g described above, the observable areas 8 of the three landmarks 4d, 4f, and 4g overlap in the area 81 shown in FIG. It can be said that 4d, 4f and 4g are observable. Similarly, it can be said that the two landmarks 4d and 4f are observable from the area 82a shown in FIG. 4, and the two landmarks 4f and 4g are observable from the area 82b. In addition, one landmark 4d is observable in the area 83a shown in FIG. 4, one landmark 4f is observable in each of the areas 83b and 83c, and one landmark 4d is observable in the area 83d. It can be said that it is observable.

FIG. 5 is a schematic diagram of an observable area map generated in this embodiment. As shown in FIG. 5, the observable area map generation unit 14 generates a grid in the area where the autonomous mobile body 5 can move on the map stored in the map database 10, and observable for all the landmarks 4. The result of estimating area 8 can be reflected in the grid. Specifically, each grid is classified and visualized according to the number of overlapping observable areas 8 . For example, in FIG. 5, the larger the number of overlapping observable areas 8 of the landmarks 4, the higher the density of the dots displayed in the grid.

The observable area map generation unit 14 thus estimates the observable area 8 in which the landmark 4 can be observed from the autonomous mobile body 5 for each of the plurality of landmarks 4, and adds the plurality of observable areas 8. Generate a combined observable area map (FIG. 5). The observable area map generation unit 14 outputs the generated observable area map to the moving route generation unit 15 .

Next, the movement route generation unit 15 generates a movement route using the estimated observable area 8 and sets the direction in which the environment recognition sensor 11 is directed (step S16). Specifically, the movement route generation unit 15 uses the observable area map generated by the observable area map generation unit 14 and the evaluation function f shown in the following equation (1) to determine the movement of the autonomous mobile body 5. A route is generated and a direction in which the environment recognition sensor 11 acquires external environment information is set.
f(x, y, θ)
=F(n _t (x, y, θ), D _t (x, y, θ), C _t,t-1 , 1/Z _t,t-1 , 1/L)
... (1)

Here, the variable n _t (x, y, θ) of the function F shown in Equation (1) is the position coordinate (x, y) in the map, and the external environment information of the environment recognition sensor 11 is acquired. The number of landmarks 4 observable from the autonomous mobile body 5 whose direction is θ is shown. Also, the variable D _t (x, y, θ) is the position coordinates (x, y) in the map, and the direction in which the environment recognition sensor 11 acquires the external environment information is θ. 4 shows the distribution of landmarks 4 within the observable field of view from body 5. FIG. Also, the variable C _t,t-1 indicates the ratio of commonly observable landmarks 4 in multiple observations from the autonomous mobile body 5 between time t and time (t-1). Variable C _t,t-1 is, for example, the number of landmarks 4 observable in common between observation at time t and observation at time (t- ₁ ). It is represented by the following formula (2).
C _t,t-1 =2×n _t,t-1 /(n _t +n _t-1 ) (2)
A variable Z _t,t-1 indicates the amount of change in the direction in which the environment recognition sensor 11 acquires external environment information between time t and time (t-1). Also, the variable L indicates the distance from the current location of the autonomous mobile body 5 to the destination. Since the smaller the variable Z _t,t-1 and the variable L, the smaller the estimation error of the current location of the autonomous mobile body 5, the reciprocals of these variables are included as variables of the function F ing.

FIG. 6 is a schematic diagram showing a moving route generated in this embodiment. The movement path 30 of the autonomous mobile body 5 is an area included in the observable area 8 estimated by the observable area map generation unit 14, and the position coordinates (x, y) in the map where the evaluation function f is maximized is generated so that it preferentially passes through FIG. 6 shows the generated result. A movement route 30 shown in FIG. 6 is generated so as to pass through grids having large values of the evaluation function f. Specifically, the moving path 30 is generated so as to pass through a grid with a high density of dots indicating a large value of the evaluation function f among the grids shown in FIG. At this time, for example, the minimum inner diameter of the curved portion of the movement route 30 may be set in consideration of the motion restrictions of the autonomous mobile body 5 such as the angle at which the steering wheel of the autonomous mobile body 5 turns.

In addition, when the environment recognition sensor 11 is fixed to the autonomous mobile body 5 as in the present embodiment, the observation of the landmark 4 may be impaired due to motion restrictions of the autonomous mobile body 5 . Therefore, in the present embodiment, the movement route generation unit 15 sets not only the generation of the movement route 30 but also the direction in which the environment recognition sensor 11 acquires the external environment information on the movement route 30 .

FIG. 7 is a schematic diagram showing directions in which the environment recognition sensor 11 set in this embodiment acquires external environment information. FIG. 7 shows a moving route 30 of the autonomous mobile body 5 shown in FIG. The movement route generator 15 sets the direction θ in which the environment recognition sensor 11 acquires the external environment information at each location on the movement route 30 so that the evaluation function f becomes the maximum. In FIG. 7, the directions in which the environment recognition sensor 11 acquires the external environment information are indicated by reference numerals 31 to 36 as an example. For example, the landmarks 4b and 4c are located in the direction in which the environment recognition sensor 11 acquires external environment information indicated by reference numeral 31, for example. For example, landmarks 4f and 4e are located in the direction in which the environment recognition sensor 11 acquires the external environment information indicated by reference numeral 32 . The same applies to reference numerals 33-36. As described above, in the present embodiment, the moving route generation unit 15 determines the direction in which the environment recognition sensor 11 acquires the external environment information so that the evaluation function f is maximized on the moving route 30 of the autonomous mobile body 5. set.

According to the travel route generation device 1 of the present embodiment described above, the travel route generation unit 15 uses the observable area 8 in which the landmarks 4 can be observed, which is estimated by the observable area map generation unit 14. Generate a moving route 30 . Since the movement route 30 of the autonomous mobile body 5 is generated so as to preferentially pass through the observable area 8, the autonomous mobile body 5 moving on the movement route 30 has a landmark 4 for estimating the current location. can be reliably observed. As a result, the positional accuracy of the estimated current location of the autonomous mobile body 5 can be improved, and the error at the destination 6 can be reduced because the destination 6 can be reached without becoming unable to move due to losing sight of the current location. can be done. Therefore, the autonomous mobile body 5 can reach the destination 6 more reliably and accurately.

FIG. 8 is a schematic diagram showing a travel route generated by a travel route generation method of a comparative example. The map shown in FIG. 8 is the same as the map stored in the map database 10 of the present embodiment (see FIG. 3). from the current location to the destination 6 are generated so as to minimize the cost. FIG. 8 shows a planned movement route 40a after the point 41 among the movement routes 40 generated by the movement route generation method of the comparative example, and shows a movement route 40 actually moved after the point 41. 40b.

In the moving route 40 shown in FIG. 8 , it can be seen that the position of the autonomous mobile body 5 begins to have an error at a point 41 on the moving route 40 . As can be seen from the observable area map shown in FIG. 5, it is difficult to recognize the landmark 4 in the vicinity of the landmark 4f. This is because an error occurs. Therefore, in the movement route 40 generated by the movement route generation method of the comparative example, after passing the point 41, the planned movement route 40a is not passed, but the movement route 40b is passed, as shown in FIG. As a result, there is a risk that the final destination will be deviated.
On the other hand, in the present embodiment, since the travel route 30 allows the landmarks 4 to be reliably observed, the destination 6 can be reached while the positional accuracy of the current location is high. Therefore, the autonomous mobile body 5 can reach the destination 6 more reliably and accurately.

In addition, the movement route generation device 1 of the present embodiment recognizes the external environment of the autonomous mobile body 5 and includes an environment recognition sensor 11 that acquires external environment information. The direction in which the environment recognition sensor 11 acquires the external environment information is set. As a result, the environment recognition sensor 11 can reliably detect the landmark 4, so that the estimation error of the current location of the autonomous mobile body 5 can be further reduced.

In addition, the moving route generation device 1 of the present embodiment compares the information about the landmarks 4 detected by the landmark detection unit 12 with the information about the landmarks 4 included in the map information, and determines the current location of the autonomous mobile body 5. A current position estimating unit 13 for estimating is provided. The moving route generator 15 generates a moving route 30 from the current location estimated by the current location estimating unit 13 to the destination 6 . This improves the positional accuracy of the current location, which is the starting point of the movement route 30, so that the autonomous mobile body 5 can reach the destination with higher accuracy.

Further, according to the movement route generation device 1 of the present embodiment, the movement route generation unit 15 generates the movement route 30 using the evaluation function f shown in Equation (1). The evaluation function f is the number of landmarks 4 observable from the autonomous mobile body 5, the dispersion state of the landmarks 4 within the field of view observable from the autonomous mobile body 5, and the autonomous mobile body 5 at predetermined time intervals. and the amount of change in the direction in which the environment recognition sensor 11 acquires the external environment information at predetermined time intervals are included as variables. According to this configuration, the movement route generation unit 15 can generate the movement route 30 that makes it easier to observe the landmarks 4, so that the autonomous mobile body 5 can more reliably and accurately reach the destination. can be reached.

<Second embodiment>
FIG. 9 is an explanatory diagram showing a schematic configuration of the movement route generation device of the second embodiment. Compared with the movement route generation device (FIG. 1) of the first embodiment, the movement route generation device 2 of the second embodiment has a landmark selection unit 16, an obstacle detection unit 17, and an obstacle position prediction unit 18. , is different.

The landmark selection unit 16 is electrically connected to the current position estimation unit 13 , the observable area map generation unit 14 and the map database 10 . The landmark selection unit 16 estimates the degree of contribution of the landmarks 4 to the estimation of the current location of the autonomous mobile body 5, and selects the landmarks 4 with high degree of contribution.
Specifically, the landmark selection unit 16 selects the size and stability of the observable range when collating with the landmarks 4 detected by the landmark detection unit 12 from a plurality of data stored in the map database 10. for each of the landmarks 4 in . The estimation result of the breadth and stability of the observable range of each of the plurality of landmarks 4 becomes the degree of contribution to estimation of the current location of the autonomous mobile body 5 . Here, the stability of the landmarks 4 is evaluated from the comparison results between different observations when generating maps stored in the map database 10 . The landmark selection unit 16 selects landmarks 4 with a high degree of contribution using this estimation result. In the selection of the landmarks 4 by the landmark selection unit 16 of the present embodiment, the landmarks 4 whose degree of contribution to the estimation of the current location of the autonomous mobile body 5 is higher than a predetermined value, and the landmarks whose degree of contribution is less than or equal to the predetermined value Divide into 4 and 2 halves. In addition, the landmark selection unit 16 may select a level to be used in consideration of the number of landmarks 4 by stratifying according to a plurality of criteria.

The obstacle detection section 17 is electrically connected to the environment recognition sensor 11 . The obstacle detection unit 17 detects moving obstacles among the obstacles included in the external environment information acquired by the environment recognition sensor 11 . When the environment recognition sensor 11 is a camera, for example, it is possible to recognize moving obstacles for the autonomous mobile body 5 such as people and robots by pattern recognition. Also, if the camera is a stereo camera, it is possible to acquire distance information, so it is possible to detect a moving obstacle from the positional change of the obstacle over time. The same is true for sensors using lasers, such as laser range finders. The obstacle detection unit 17 detects time changes in the external environment information by filtering such as a Kalman filter, determines whether or not the obstacle is moving, and if it is a moving obstacle, detects its position and moving direction. to estimate

The obstacle position prediction unit 18 is electrically connected to the obstacle detection unit 17 and the observable area map generation unit 14 . The obstacle position prediction unit 18 calculates the moving trajectory of the moving obstacle detected by the obstacle detecting unit 17, and estimates the position of the moving obstacle at a specific time t.

FIG. 10 is a flow chart of the movement route generation method of this embodiment. Next, a method of generating a movement route of the autonomous mobile body 5 by the movement route generation device 2 will be described.

First, as in steps S10 and S11 of the first embodiment, the map database 10 stores map information on which the autonomous mobile body 5 moves (step S20), and the environment recognition sensor 11 acquires external environment information. (Step S21). Next, similarly to steps S12 and S13 of the first embodiment, the landmark detection unit 12 detects the landmark 4 from the external environment information (step S22), and the current location estimation unit 13 detects information about the detected landmark. and information about landmarks in the map information to estimate the current location of the autonomous mobile body 5 (step S23).

Next, the obstacle detection unit 17 detects moving obstacles included in the external environment information (step S24). Specifically, as described above, the obstacle detection unit 17 detects a moving obstacle among the obstacle information included in the external environment information output by the environment recognition sensor 11 as a moving obstacle. The obstacle detection unit 17 estimates the position and moving direction of the detected moving obstacle using the obstacle information. The obstacle detection section 17 outputs information about the moving obstacle to the obstacle position prediction section 18 .

Next, the obstacle position prediction unit 18 predicts the position of the moving obstacle at time t (step S25). Specifically, the obstacle position prediction unit 18 uses the information about the moving obstacle output by the obstacle detection unit 17 to calculate the moving trajectory of the moving obstacle and estimate the position at time t.

FIG. 11 is a schematic diagram showing the movement trajectory of the moving obstacle in this embodiment. In the map of FIG. 11(a), a moving obstacle 51a is positioned near landmarks 4g, 4i, 4j, and 4k. The moving obstacle 51a is moving to draw an ellipse, like the moving locus 51b shown in FIG. 11(a). The obstacle position prediction unit 18 uses the information about the moving obstacle 51a output by the obstacle detection unit 17 to calculate the movement trajectory 51b and estimate the position at a specific time.

FIG. 12 is a schematic diagram showing the movement trajectory of another moving obstacle in this embodiment. In the map of FIG. 12(a), a moving obstacle 52a is positioned near landmarks 4d, 4e, and 4f. The moving obstacle 52a moves so as to reciprocate in a certain section, as shown by a movement trajectory 52b shown in FIG. 12(a). The obstacle position prediction unit 18 uses the information about the moving obstacle 52a output by the obstacle detection unit 17 to calculate the movement trajectory 52b and estimate the position at a specific time. The obstacle position prediction unit 18 outputs the information of the movement trajectories 51b and 52b of the moving obstacles 51a and 52a to the observable area map generation unit 14 .
Next, as in step S14 of the first embodiment, the current location estimation unit 13 acquires destination information (step S26).

Next, the landmark selection unit 16 estimates the degree of contribution to estimation of the current location of the autonomous mobile body 5 for each landmark 4 (step S27). Specifically, as described above, the landmark selection unit 16 estimates the breadth and stability of the observable range for each landmark 4, and the landmarks that contribute highly to the estimation of the current location of the autonomous mobile body 5 4 is selected. The landmark selection unit 16 outputs the selected landmarks 4 to the observable area map generation unit 14 .

Next, the observable area map generator 14 estimates the observable area 8 of the landmark 4 using the map information (step S28). Specifically, the observable area map generation unit 14 uses the map information in which the landmarks 4 are distributed, which is acquired from the map database 10, to map the observable area 8 for the landmarks 4 selected by the landmark selection unit 16. to estimate

Next, the observable area map generator 14 modifies the observable area 8 of the landmark 4 in consideration of the effects of the moving obstacles 51a and 52a (step S29). The processing in the observable area map generation unit 14 in step S29 will be specifically described with reference to FIGS. 11 and 12. FIG.

In FIG. 11(a), as described above, the moving obstacle 51a moves so as to draw an ellipse in the vicinity of the landmarks 4g, 4i, 4j, and 4k. When the autonomous mobile body 5 directs the environment recognition sensor 11 toward the landmarks 4i and 4j from the position shown in FIG. , the environment recognition sensor 11 cannot recognize the landmarks 4i and 4j blocked by the moving obstacle 51a. For this reason, the autonomous mobile body 5 at the position shown in FIG. 11A may cause an error in estimating the current location. Therefore, the observable area map generation unit 14 corrects the observable area 8 estimated in step S28 from the information on the movement trajectory 51b of the moving obstacle 51a output by the obstacle position prediction unit 18. FIG. With this modification, in the dot density display shown in FIG. 11(a), the dot density displayed in the grid near the landmarks 4i and 4j is reduced (possible in this embodiment with the moving obstacle 51a). (See FIG. 11(a) for the observation area map and FIG. 11(b) for the observable area map of the first embodiment without moving obstacles).

Also, in FIG. 12(a), as described above, the moving obstacle 52a moves so as to reciprocate in a certain section in the vicinity of the landmarks 4d, 4e, and 4f. When the autonomous mobile body 5 passes near the movement locus 52b of the moving obstacle 52a, the autonomous mobile body 5 and the moving obstacle 52a may come into contact with each other. Therefore, the observable area map generation unit 14 corrects the observable area 8 estimated in step S28 from the information on the movement trajectory 52b of the moving obstacle 52a output by the obstacle position prediction unit 18. FIG. As a result of this modification, in the dot density display shown in FIG. 12(a), dots in the grid near the movement trajectory 52b of the moving obstacle 52a are no longer displayed, and are completely excluded from the observable area. (See FIG. 12(a) of the observable area map of the present embodiment with the moving obstacle 52a and FIG. 11(b) of the observable area map of the first embodiment without the moving obstacle.).
The observable area map generator 14 outputs the observable area map corrected in step S<b>29 to the moving route generator 15 .

Next, the movement route generation unit 15 generates a movement route using the estimated observable area 8 and sets the direction in which the environment recognition sensor 11 is directed (step S30). The movement route generation unit 15 uses the observable area map corrected in step S29 output by the observable area map generation unit 14 and the evaluation function f shown in Equation (1) to determine the movement route of the autonomous mobile body 5. Generate and set the direction in which the environment recognition sensor 11 is directed

FIG. 13 is a schematic diagram showing a moving route generated in this embodiment. The map of FIG. 13 shows an observable area map obtained by combining the modified observable area maps shown in FIGS. 11(a) and 12(a). In step S30, the moving route generator 15 generates the moving route 50 of the autonomous mobile body 5 using the map shown in FIG. In FIG. 13, as a comparative example, a moving path 30 generated in the first embodiment without moving obstacles is indicated by a dotted line. A travel path 50 is generated through a dense grid of dots in the modified observable area map. Compared to the moving route 30 generated in the first embodiment, the surroundings of the moving obstacle 51a forming a shielded area in which information about the landmarks 4i and 4j are not included in the external environment information acquired by the environment recognition sensor 11, It becomes a moving route that does not pass near the moving obstacle 52a that may collide.

According to the movement path generation device 2 of this embodiment described above, the obstacle position prediction unit 18 calculates the movement trajectories 51b and 52b of the moving obstacles 51a and 52a, and calculates the position of the moving obstacle at a specific time. to estimate The observable area map generation unit 14 uses the estimation result of the position of the moving obstacle 51a by the obstacle position prediction unit 18 to determine whether the external environment information acquired by the environment recognition sensor 11 includes information about the landmarks 4i and 4j. The observable area 8 is corrected by excluding the disappearing shielded area from the observable area 8. - 特許庁As a result, it is possible to prevent the environment recognition sensor 11 of the autonomous mobile body 5 moving on the movement path 50 from losing sight of the current location due to being unable to detect the landmark 4 . Therefore, the autonomous mobile body 5 can reach the destination more reliably.

Further, according to the movement route generation device 2 of the present embodiment, the observable area map generation unit 14 calculates the movement trajectory 52b of the moving obstacle 52a by the obstacle position prediction unit 18, Observable area 8 is modified to prevent collision with object 52a. As a result, the autonomous mobile body 5 can be prevented from being unable to move due to a collision with the moving obstacle 52a, so that the autonomous mobile body 5 can reach the destination more reliably.

Further, according to the movement route generation device 2 of the present embodiment, the landmark selection unit 16 selects the landmarks 4 according to the degree of contribution to position estimation of the autonomous mobile body 5 . The observable area map generator 14 generates an observable area map only from the observable areas 8 of the landmarks 4 selected by the landmark selector 16 . As a result, instead of estimating the observable area 8 for all the landmarks 4, the observable area map generation unit 14 estimates the observable area for the landmarks 4 that contribute highly to the position estimation of the autonomous mobile body 5. Because of the estimation, the moving route 50 can be generated in a shorter time and with less effort. Therefore, it is possible to increase the efficiency and speed of the generation process of the movement route 50 in the movement route generation device 2 .

<Modification of this embodiment>
The present invention is not limited to the above-described embodiments, and can be implemented in various aspects without departing from the scope of the invention. For example, the following modifications are possible.

[Modification 1]
In the above-described embodiments, the movement route generation device is assumed to be mounted on an autonomous mobile body. However, the place where the moving route generation device is placed is not limited to this. Only the environment recognition sensor 11 is mounted on the autonomous mobile body 5, and the landmark detection unit 12, the current location estimation unit 13, the observable area map generation unit 14, the moving route generation unit 15, and the map database 10 are It may be placed outside the autonomous mobile body. In this case, the observation data acquired by the environment recognition sensor 11 is transmitted to the landmark detection unit 12 by radio or the like, and the movement route generated by the movement route generation unit 15 is transmitted to the autonomous mobile body 5. 5 will move.

[Modification 2]
In the above-described embodiment, the moving route generator 15 sets the direction in which the environment recognition sensor 11 acquires the external environment information. However, the movement route generator 15 may generate only the movement route. For example, if the environment recognition sensor 11 is a camera capable of observing all directions, it is not necessary to set the direction in which the environment recognition sensor 11 acquires external environment information.

[Modification 3]
In the second embodiment, the landmark selection unit 16 selects the landmarks 4 that have a large degree of contribution to the estimation of the current location of the autonomous mobile body 5, and the observable area map generation unit 14 selects the landmarks 4 that have a large degree of contribution. It is assumed that the observable area map is generated only with the observable area 8 of . However, the observable area map generation method is not limited to this. For example, the observable area map generation unit 14 estimates the observable area 8 reflecting the weight of the degree of contribution for all the landmarks 4, and calculates the observable area 8 of all the landmarks 4 according to the weight. The observable area map may be generated by a method of summing the

[Modification 4]
In the above-described embodiment, the moving route generation unit 15 generates the moving route using the observable area map and the evaluation function f shown in Equation (1) including multiple variables. However, the variables of the evaluation function f are not limited to this. At least one of the variables described above may be used, and for example, the total amount of movement of the autonomous mobile body 5 may be used as the variable. Also, evaluation may be performed in combination with another evaluation function. Also, the moving route generation unit 15 may generate a moving route only in the observable area.

[Modification 5]
In the above-described embodiment, the moving route generation device is assumed to generate the moving route from the current location to the destination at once. However, it is also possible to set an intermediate location between the current location and the destination, generate a moving route from the current location to the intermediate value, and then sequentially generate the route to the destination.

[Modification 6]
In the above-described embodiment, the observable area map indicates the ease of observation by grid representation, but it may be represented by a graph or grid nodes.

[Modification 7]
In the second embodiment, the movement route generation device 2 is provided with the landmark selection unit 16, the obstacle detection unit 17, and the obstacle position prediction unit 18. Only the landmark selection unit 16 may be used, or only the combination of the obstacle detection unit 17 and the obstacle position prediction unit 18 may be used.

The present aspect has been described above based on the embodiments and modifications, but the above-described embodiments are intended to facilitate understanding of the present aspect, and do not limit the present aspect. This aspect may be modified and modified without departing from its spirit and scope of the claims, and this aspect includes equivalents thereof. Also, if the technical features are not described as essential in this specification, they can be deleted as appropriate.

1, 2... movement path generation device 4, 4b, 4c, 4d, 4e, 4f, 4g, 4h, 4i, 4j, 4k, 4l, 4m, 4n, 4o, 4p, 4q, 4r, 4s, 4t, 4u, 4v... Landmark 5... Autonomous mobile body 6... Destination 7, 7a, 7b, 7c, 7d, 7e, 7f, 7g, 7h, 7i, 7j, 7k... Obstacle 8, 8d, 8f, 8g... Observable area DESCRIPTION OF SYMBOLS 10... Map database 11... Environment recognition sensor 12... Landmark detection part 13... Current position estimation part 14... Observable area map generation part 15... Movement path generation part 16... Landmark selection part 17... Obstacle detection part 18... Obstacles Position prediction unit 30, 50 Moving route 41 Point 51a, 52a Moving obstacle 51b, 52b Moving trajectory 81, 82a, 82b, 83a, 83b, 83c, 83d Region

Claims (7)

A movement route generation device that generates a movement route from the current location of an autonomous mobile body to a destination,
a map information storage unit for storing map information including information on landmarks for estimating the position of the autonomous mobile body, and information on positions where the landmarks can be seen;
An observable area estimation unit that estimates an observable area in which the landmark can be observed from the current location of the autonomous mobile body to a destination using the map information , wherein the external environment of the autonomous mobile body is estimated. an observable area estimation unit that generates an observable area map based on the observable area without using external environment information for recognition;
a moving route generating unit that generates the moving route that preferentially passes through the observable area using the observable area map generated by the observable area estimating unit;
an environment recognition sensor that is arranged on the autonomous mobile body and acquires the external environment information;
a landmark detection unit that detects information about the landmarks included in the external environment information;
estimating the current location of the autonomous mobile body that is moving on the movement route by collating the information regarding the landmarks detected by the landmark detection unit and the information regarding the landmarks included in the map information; a current location estimation unit ;
Movement path generation device. The moving route generation device according to claim 1 ,
The movement route generation unit sets a direction in which the environment recognition sensor acquires the external environment information to a direction in which the landmark can be observed.
Movement path generation device. The moving route generation device according to claim 1 or claim 2 further comprises:
an obstacle detection unit that detects information about a moving obstacle included in the external environment information;
an obstacle position prediction unit that predicts a position change of the moving obstacle using information about the detected moving obstacle;
The observable area estimation unit,
Using the positional change prediction of the moving obstacle by the obstacle position prediction unit, the moving obstacle is positioned between the environment recognition sensor and the landmark, thereby obtaining the external image obtained by the environment recognition sensor. estimating a shielded area where environmental information no longer contains information about the landmark;
excluding the occluded area from the observable area;
Movement path generation device. The moving route generation device according to any one of claims 1 to 3 ,
The moving route generation unit
The number of landmarks observable from the autonomous mobile body;
a dispersed state of the landmarks within a field of view observable from the autonomous mobile body;
A ratio of the commonly observable landmarks in multiple observations from the autonomous mobile body at predetermined time intervals;
generating the movement route using at least one of a change amount in a direction in which the environment recognition sensor acquires the external environment information at a predetermined time interval;
Movement path generation device. The moving route generation device according to any one of claims 1 to 4 further comprises:
A landmark selection unit that estimates the degree of contribution of the landmark to position estimation of the autonomous mobile body using information about the landmark included in the map information,
The observable area estimation unit estimates an observable area of only the landmarks with the high contribution, or an observable area that reflects the weight of the contribution.
Movement path generation device. A movement route generation method in which a movement route generation device generates a movement route from the current location of an autonomous mobile body to a destination,
a map information storage step of storing, in a map information storage unit, map information including information on landmarks for estimating the position of the autonomous mobile body and information on positions where the landmarks can be seen;
An observable area estimation step in which an observable area estimation unit estimates an observable area in which the landmark can be observed from the current location of the autonomous mobile body to a destination using the map information , wherein the autonomous an observable area estimation step of generating an observable area map based on the observable area without using external environment information for recognizing the external environment of the moving object;
A movement route generation step in which a movement route generation unit generates the movement route that preferentially passes through the observable area using the observable area map generated in the observable area estimation step ;
an environment recognition step of acquiring external environment information for recognizing the external environment of the autonomous mobile body;
a landmark detection step of detecting information about the landmarks included in the external environment information;
estimating the current location of the autonomous mobile body that is moving on the movement route by collating the information regarding the landmarks detected in the landmark detection step and the information regarding the landmarks included in the map information; a current location estimation step ;
Movement route generation method. A computer program that causes a computer to generate a movement route from the current location of an autonomous mobile body to a destination,
A map information storage function for storing map information including information on landmarks for estimating the position of the autonomous mobile body, and information on positions where the landmarks can be seen;
An observable area estimation function for estimating an observable area in which the landmark can be observed from the current location of the autonomous mobile body to a destination using the map information, wherein the external environment of the autonomous mobile body is estimated. an observable area estimation function that generates an observable area map based on the observable area without using external environment information for recognition;
A movement route generation function that generates the movement route that preferentially passes through the observable area using the observable area map generated by the observable area estimation function;
an environment recognition function for acquiring external environment information for recognizing the external environment of the autonomous mobile body;
a landmark detection function for detecting information about the landmarks included in the external environment information;
estimating the current location of the autonomous mobile body that is moving on the movement route by collating information on the landmarks detected by the landmark detection function and information on the landmarks included in the map information; causing the computer to perform a current location estimation function ;
computer program.

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