JP4997615B2 - Map creation method and robot movement route determination method - Google Patents

Description

  The present invention relates to a technique for creating map information used to determine a movement path of a robot, and a technique for determining a movement path of a robot using the map information.

  There is known an autonomous robot in which a robot itself automatically calculates a route and moves to a goal only by specifying a goal (destination) for the robot. In order to realize such an operation, map information in an environment (area) in which the robot moves needs to be created in advance and taught to the robot. As one of the methods for that purpose, there has been proposed a method in which the robot itself moves (searches) all around the environment to create a map (see Non-Patent Document 1). However, this method has a problem that it takes a certain amount of search time to create a map and cannot be used immediately when a robot is introduced into a new environment. Moreover, what is obtained by the search is only internal data indicating the movable range of the robot. For example, in order to be able to specify a destination by the name of a place such as “kitchen” or “living room”, it is necessary to associate the name (meaning) of the place with the internal data of the robot ( This is called the “labeling problem.”) It is unexpectedly difficult to let the user perform this work. As another method, a method of monitoring the position of a robot using a sensor such as a ceiling camera or a wireless system is also known. However, this type of system is cumbersome to install and calibrate the sensor equipment, and is difficult to introduce, especially for home robots. This method also does not solve the labeling problem described above.

J. J. Leonard and H. F. Durrant-whyte, “Simultaneous map building and localization for an autonomous mobile robot,” Proc. IEEE / RSJ International Workshop on Intelligent Robots and Systems (IROS 91), vol. 3, pp. 1442-1447, 1991

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a technique capable of realizing the creation and teaching of map information by an extremely simple and intuitive operation.

  In order to achieve the above object, a map creation system according to the present invention is a map creation system for creating map information to be used for route determination when a robot moves in an environment, and different identifiers are assigned. The plurality of landmark devices are arranged at arbitrary positions in the environment by the user, and each landmark device is adjacent to the surrounding of the own device. A communication unit that performs optical wireless communication with the landmark device, a detection unit that acquires an identifier of the adjacent landmark device by optical wireless communication, and detects an orientation of the adjacent landmark device with respect to the own device; Information generating means for generating adjacent device information including an identifier of the adjacent landmark device and an identifier and direction of the adjacent landmark device. By marking device mutually interchangeable neighboring device information in optical wireless communication, characterized in that to create a map information indicating a relative positional relationship between the plurality of landmarks device.

  According to this configuration, the user's specific work is performed at an appropriate interval (= in a location capable of optical wireless communication with one or more landmark devices) at a place that is likely to be a destination or route of the robot. All you need is a simple and intuitive task of installing the marking device. With this alone, the landmark devices can understand each other's positional relationship and automatically create map information, so the introduction of the system is extremely easy. Further, since the map information is completed simply by exchanging information between the landmark apparatuses, the preparation time required for creating the map information can be greatly shortened.

  Here, “optical wireless communication” refers to wireless communication using electromagnetic waves (light rays) having a wavelength ranging from infrared rays to visible rays, and typically infrared communication can be used. By using optical wireless communication, there is an advantage that the landmark device can be reduced in size and can be used for detecting the direction of the adjacent landmark device because of its high directivity. In addition, the fact that optical wireless communication is possible means that there are no obstacles between landmark devices, so it is possible to recognize the adjacent relationship of landmark devices based on the availability of optical wireless communication and create map information on the route. It also has the effect of ensuring that there are no obstacles.

  In the above-described configuration, the communication unit includes a plurality of light receiving units attached to the apparatus main body in different directions, and the detection unit is adjacent based on reception states in the plurality of light receiving units. It is preferable to detect the orientation of the landmark device. By using the optical wireless communication device for azimuth detection in this way, the landmark apparatus can be reduced in size and cost.

  The robot system according to the present invention includes a robot and the above-described map creation system, and the robot performs optical wireless communication between a moving mechanism and a landmark device of the map creation system. Means, a goal designating means for allowing the user to designate an identifier of any one of the landmark devices as a goal point, map information is obtained from the nearest landmark device by optical wireless communication, and the obtained map information and the goal point are A route calculation means for calculating, as a route, the order of landmark devices to be traced from the nearest landmark device to the landmark device designated as the goal point based on the identifier of the designated landmark device; The moving mechanism is controlled so that the robot moves according to the route obtained by the calculating means. Is characterized in further comprising control means for, the.

  According to this configuration, the user can perform a simple and intuitive operation of instructing the robot the identifier of the landmark device that is the goal point. In addition, since the landmark device itself also plays a role as a physical label, labeling processing (corresponding to map information and location), which has been conventionally required, becomes unnecessary. It is only necessary to remember which identifier device with which identifier is located.

  The present invention can be understood as a map creation system or robot system having at least a part of the above means. In addition, the present invention can also be understood as a map creation method including at least a part of the above processing, a robot movement route determination method, a robot control method, and the like. It can also be understood as a program for executing the program or a recording medium on which the program is recorded.

For example, a map creation method according to one aspect of the present invention is a map creation method for creating map information used for determining a route when a robot moves in an environment, and a user is given different identifiers. A plurality of landmark devices arranged at arbitrary positions in the environment, and each landmark device performs optical wireless communication with adjacent landmark devices arranged around the own device. Obtaining the identifier of the adjacent landmark device, detecting the orientation of the adjacent landmark device with respect to the own device, and each landmark device includes the identifier of the own device and the identifier and orientation of the adjacent landmark device. Generating the neighboring device information, and exchanging the neighboring device information with each other by optical wireless communication between the plurality of landmark devices. Is characterized in that it has a, a step of creating a map information indicating a relative positional relationship between the over-click device.

  According to another aspect of the present invention, there is provided a method for determining a movement path of a robot in which a plurality of landmark devices are arranged in advance and a relative positional relationship between the plurality of landmark devices is determined by the map creation method. A step of creating map information to be represented, a step in which the user designates one of the landmark device identifiers as a goal point for the robot, and the robot performs map information from the nearest landmark device by optical wireless communication. And the robot follows from the nearest landmark device to the landmark device designated as the goal point based on the obtained map information and the identifier of the landmark device designated as the goal point. And a step of calculating the order of the landmark devices as a route.

  According to the present invention, creation and teaching of map information can be realized by an extremely simple and intuitive operation.

The figure which shows the outline | summary of a robot system typically. The figure which shows the structure of a robot and a landmark apparatus. The figure which shows the map creation process by a landmark apparatus. The flowchart regarding the route determination and movement of a robot.

  Exemplary embodiments of the present invention will be described in detail below with reference to the drawings.

<System overview>
FIG. 1 is a diagram schematically showing an outline of a robot system according to an embodiment of the present invention. This robot system includes a robot 1 having a moving mechanism and a plurality of landmark devices 2. The robot 1 and each landmark device 2 can transmit / receive data to / from each other by optical wireless communication (infrared communication in this embodiment). Each landmark device 2 is given a unique identifier, and in this embodiment, an identification number (numeral) is assigned as the identifier. Hereinafter, the landmark device 2 having the identification number N is represented as “landmark device 2-N”.

  The example shown in FIG. 1 will be described using an example in which a home transfer robot 1 is introduced into a home. First, as shown in (a), the user arranges each landmark device 2 at an arbitrary position on the floor. For example, if the robot 1 is assumed to have a kitchen, a living room, a dining room, a bedroom, and a corridor connecting the rooms, the landmark devices 2 are arranged at appropriate intervals in the rooms and the corridor. At this time, consideration is given so that there is no obstacle between the adjacent landmark devices 2. When the installation is completed, each landmark device 2 investigates the identification number and direction of the landmark device 2 existing around itself to generate neighboring device information, and the landmark devices 2 exchange neighboring device information with each other. By doing so, map information (information indicating a relative positional relationship between landmark devices) is automatically generated. Preparation for introduction is now complete.

When it is desired to move the robot 1 to the kitchen, as shown in (b), the robot 1 is instructed with the identification number “3” of the landmark device 2-3 placed in the kitchen. Then, as shown in (c), the robot 1 receives the map information from the nearest landmark device 2-7, and reaches from the nearest landmark device 2-7 to the landmark device 2-3 at the goal point. Calculate the route. In the example of (c), the movement route of 7 → 5 → 2 → 3 is selected. After that, the robot 1 follows the landmark device 2 in the order of 7 → 5 → 2 → 3 while communicating with each landmark device 2, thereby reaching the kitchen as the goal point as shown in (d). Can do.

<Device configuration>
Next, the configuration of the robot 1 and the landmark device 2 will be described with reference to FIG. 2A is a plan view, and FIG. 2B is a side view of FIG. 2A viewed from the direction of the arrow.

  The robot 1 is a self-propelled robot including a moving mechanism 10 including wheels, a drive motor, and the like, and a microcontroller 11 that performs route calculation, control of the moving mechanism, and the like. The robot 1 has an infrared light receiving unit 12, an infrared LED 13, and a camera 14 in front of the traveling direction. The infrared light receiving unit 12 and the infrared LED 13 serve as communication means for performing infrared communication with the landmark device 2. The image captured by the camera 14 is used by the microcontroller 11 for the purpose of measuring (estimating) the distance to the landmark device 2 or the purpose of detecting an obstacle. Further, a plurality of buttons 15 (goal specifying means) are provided on the main body of the robot 1. Each button 15 is associated with the landmark device 2 on a one-to-one basis. For example, when the button 15 with “3” is pressed, the landmark device 2-3 with the identification number “3” is set as the goal point. Is programmed to do so. In addition to the above configuration, the robot 1 may include an optional configuration (for example, an arm for gripping an object) according to the purpose of use, but the description thereof is omitted here.

  The landmark device 2 is a small device installed on a floor (a plane on which the robot 1 moves). Each landmark device 2 has the same configuration, and in this embodiment, eight infrared light receiving units 22, eight infrared LEDs 23, eight indicator LEDs 21, and a microcontroller 20 for controlling them are provided. It is prepared for. The infrared light receiver 22 and the infrared LED 23 serve as communication means for performing infrared communication with the adjacent landmark device 2 or with the robot 1. As shown in FIG. 2 (a), eight sets of infrared light receivers 22 and infrared LEDs 23 are equally arranged on the outer periphery of the landmark device 2, and are configured to be able to communicate with counterparts in all directions. Here, an infrared communication module using a modulation signal of 38 kHz is used.

  Each landmark device 2 transmits data from the infrared LED 23 at regular time intervals. In the initial state, only the identification number of the own device is transmitted, but after the neighboring device information and map information described later are obtained, those data are transmitted. On the other hand, each landmark device 2 receives data from the adjacent landmark device 2 existing in the periphery in the infrared light receiving unit 22 and acquires the identification number of the adjacent landmark device 2, adjacent device information, and the like.

In the present embodiment, the reception state of the infrared communication is used for detecting the direction of the adjacent landmark device 2. The principle of azimuth detection will be described with reference to FIG. The infrared signal transmitted from the landmark device 2-5 is received by the infrared light receiving unit 22 of the landmark device 2-7. At this time, signals are not received by all eight infrared light receiving units 22, but signals are detected only by the infrared light receiving units 22 facing the landmark device 2-5. This is because the straightness and directivity of infrared rays are very high. Therefore, the arrival direction of the infrared signal, that is, the azimuth of the adjacent landmark device relative to the own device can be estimated by comparing the signal intensity in each infrared light receiving unit 22 or the frequency of successful reception. In the example of FIG. 2A, the reception state at the infrared light receiving unit 22 at the upper left of the figure is the best, and the landmark apparatus 2-5 exists in the upper left direction of the figure as viewed from the landmark apparatus 2-7. It can be detected. It is possible to increase the azimuth resolution by increasing the resolution of the signal intensity in the infrared light receiver 22 or increasing the number of infrared light receivers 22.

  The indicator LED 21 is an indicator for displaying the detected orientation of the adjacent landmark device 2. In the example of FIG. 2A, the upper left one of the eight indicator LEDs 21 of the landmark device 2-7 is lit. This indicator LED 21 is mainly used for user confirmation. For example, if the indicator LEDs 21 are not lit when the landmark devices 2-5 and 2-7 are installed, the communication state between the landmark devices 2-5 and 2-7 is poor. This means that it is necessary to adjust the orientation and spacing of the device.

<Map creation process>
Next, map creation processing by the landmark apparatus will be described with reference to FIG. In FIG. 3, a graphic indicated by a circle represents a landmark device, and a number in the graphic represents an identification number of the landmark device. Also, the dotted line indicates the adjacency relationship, and the landmark devices connected by the dotted line are adjacent (= communicable).

  It is assumed that landmark devices 2-2 and 2-8 are arranged as shown in (a). Each landmark device 2-2, 2-8 transmits its own identification number to the surroundings. Accordingly, the landmark device 2-2 recognizes that the adjacent landmark device 2-8 exists in the 45 ° azimuth, and the landmark device 2-8 detects that the adjacent landmark device 2-2 has the 30 ° azimuth. Recognize that it exists. When the adjacent landmark device is detected, each landmark device creates adjacent device information. The adjacent device information is information including the identification number of the own device, the version, the identification number of the adjacent landmark device, and the direction. In the stage (a), the neighboring device information having the contents “ID2, ver1, 8-45” is generated in the landmark device 2-2, and “ID8, ver1, 2-30” is generated in the landmark device 2-8. Content neighbor device information is generated. The direction is expressed as a relative angle with respect to the reference direction of the device.

  Thereafter, as shown in (b), each of the landmark devices 2-2 and 2-8 exchanges adjacent device information, adds the adjacent device information of other devices to the adjacent device information of the own device, and stores it in the memory. To do. The list (table) of adjacent device information obtained in this way is data representing the relative positional relationship of all landmark devices constituting the network, and is used as map information in this system.

  Next, an update process of map information when a change occurs in the configuration of the landmark apparatus will be described using (c) to (e). As shown in (c), when the landmark device 2-3 is additionally installed, the landmark device 2-3 generates neighboring device information having the contents of “ID3, ver1, 2-220”. On the other hand, in the landmark device 2-2, the information “3-305” of the landmark device 2-3 is added to the existing neighboring device information, and the version number is incremented to “ver2”. Thereafter, as shown in order in (d) and (e), the exchange of adjacent device information is repeated between the landmark devices 2-2, 2-3, and 2-8, and the map information in each device is the latest. Rewrite into things.

  The reason why the version number is included in the adjacent device information is to solve the conflict of the adjacent device information. For example, in the arrangement of (c), when the landmark devices 2-3 and 2-8 can communicate with each other, the landmark device 2-3 receives “ID2, ver2, 8-445” from the device 2-2. While receiving “3-305”, there is a possibility of receiving “ID2, ver1, 8-45” from the device 2-8. As described above, when the adjacent device information related to the same identification number is received, the update processing of the map information can be correctly performed by adopting the new version.

<Robot motion>
Next, processing related to route determination and movement of the robot 1 will be described with reference to the flowchart of FIG. It is assumed that the map creation process by the landmark device 2 is completed in advance, and all the landmark devices 2 constituting the network are in a state of sharing the map information. In FIG. 4, “landmark device” is abbreviated as “LM”.

  (S100) The user presses the button 15 of the robot 1 to instruct the robot 1 of the identification number of the landmark device 2 to be the goal point.

  (S101) The robot 1 performs infrared communication with the surrounding landmark device 2 and acquires map information. At this time, the robot 1 recognizes the nearest (nearest) landmark device 2 based on the signal intensity and the reception frequency in the infrared light receiving unit 12.

  (S102) Next, the robot 1 calculates a route from the nearest landmark device to the landmark device at the goal point based on the adjacent relationship between the landmark devices included in the map information. Here, the route is determined so that the number of landmark devices that pass through is minimized. If there are a plurality of routes having the same number of routes, a route with the smallest change of direction of the robot 1 may be selected.

  (S103) When the movement path is determined, the robot 1 first sets the nearest landmark device as the target landmark device.

  (S104) Then, the robot 1 moves toward the target landmark device. At this time, the robot 1 determines and corrects the moving direction by detecting the infrared signal from the target landmark device with the infrared light receiving unit 12.

  (S105) The robot 1 calculates the distance between the robot 1 and the target landmark device by taking an image from the camera 14 every predetermined time and performing predetermined image processing. The robot 1 continues to move until the distance becomes a predetermined value or less.

  (S106) When the distance to the target landmark device is equal to or less than the predetermined value, the robot 1 refers to the route information determined in S102 and determines whether there is a next landmark device.

  (S107) If the next landmark device exists, the robot 1 sets the landmark device as the next target landmark device. Then, the robot 1 refers to the map information, calculates the azimuth of the next target landmark device with respect to the current location, changes the direction to that direction, and continues to move. Note that if the robot 1 receives an infrared signal from the next target landmark device, the moving direction is corrected as appropriate, so the azimuth calculation in S107 does not have to be very precise.

  When the processing of S104 to S107 is repeated and the landmark device at the goal point is reached, a NO determination is made in S106, and the robot 1 stops moving.

<Excellent advantages of this system>
According to the system of the present embodiment described above, the work necessary for creating the map is simple and intuitive that the landmark device is installed at an appropriate interval where it is likely to be the destination or route of the robot. It ’s just a little work. With this alone, the landmark devices can understand each other's positional relationship and automatically create map information, so the introduction of the system is extremely easy. Further, since the map information is completed simply by exchanging information between the landmark apparatuses, the preparation time required for creating the map information can be greatly shortened. In addition, since the landmark device itself also plays a role as a physical label, labeling processing (corresponding to map information and location), which has been conventionally required, becomes unnecessary. The user only has to remember which identification number of the landmark device is placed in which location.

  Further, in the present embodiment, infrared communication is used for communication between landmark devices, so that the landmark device can be reduced in size and cost, and can be used for azimuth detection of adjacent landmark devices. is there. In addition, the fact that infrared communication is possible means that there are no obstacles between landmark devices, so it is possible to recognize obstacles on the route by recognizing the adjacency of landmark devices based on the availability of infrared communication and creating map information. There is also an effect to guarantee that there is nothing.

<Modification>
The above embodiment is merely an example of the present invention. The scope of the present invention is not limited to the above embodiment, and various modifications can be made within the scope of the technical idea. For example, although infrared communication is used in the above embodiment, wireless communication using visible light can also be used. It is also preferable to provide the infrared light receiving unit of the robot not only in the front but also in a plurality of directions. Further, the moving mechanism of the robot is not limited to the wheel, and a moving mechanism such as a leg or a levitation device can be provided. Further, instead of an image sensor using a camera, another type of sensor can also be used for distance measurement and obstacle detection.

1: Robot 2: Landmark device 10: Movement mechanism 11: Microcontroller 12: Infrared light receiving unit 13: Infrared LED
14: Camera 15: Button 20: Microcontroller 21: Indicator LED
22: Infrared light receiver 23: Infrared LED

Claims (5)

A map creation system for creating map information used for route determination when a robot moves in an environment,
It is composed of a plurality of landmark devices to which different identifiers are assigned, and the plurality of landmark devices are arranged at arbitrary positions in the environment by the user,
Each landmark device
Communication means for performing optical wireless communication with adjacent landmark devices arranged around the own device;
While detecting the identifier of the adjacent landmark device by optical wireless communication, detecting means for detecting the orientation of the adjacent landmark device relative to its own device,
Information generating means for generating adjacent device information including the identifier of the own device and the identifier and direction of the adjacent landmark device;
A plurality of landmark devices create map information representing a relative positional relationship between the plurality of landmark devices by exchanging adjacent device information with each other by optical wireless communication. system. The communication means has a plurality of light receiving units attached to different orientations with respect to the apparatus body,
The map creating system according to claim 1, wherein the detecting unit detects an orientation of an adjacent landmark device based on reception states in the plurality of light receiving units. A robot system having a robot and the map creation system according to claim 1 or 2,
The robot is
A moving mechanism;
Communication means for performing optical wireless communication with the landmark device of the map creation system;
Goal specifying means for allowing the user to specify an identifier of any one landmark device as a goal point;
The map information is acquired from the nearest landmark device by optical wireless communication, and the landmark device specified as the goal point is specified from the nearest landmark device based on the acquired map information and the identifier of the landmark device specified as the goal point. A route calculation means for calculating the order of the landmark device to be traced up to the landmark device as a route;
Control means for controlling the moving mechanism so that the robot moves according to the route obtained by the route calculating means;
A robot system characterized by comprising: A map creation method for creating map information used for route determination when a robot moves in an environment,
A user arranges a plurality of landmark devices provided with different identifiers at arbitrary positions in the environment;
Each landmark device acquires an identifier of the adjacent landmark device by performing optical wireless communication with adjacent landmark devices arranged around the own device, and the direction of the adjacent landmark device with respect to the own device. Detecting
Each landmark device generates neighboring device information including the identifier of the own device and the identifier and direction of the neighboring landmark device;
A step of creating map information representing a relative positional relationship between the plurality of landmark devices by exchanging neighboring device information with each other by optical wireless communication between the plurality of landmark devices;
A method for creating a map, comprising: A method for determining a movement path of a robot,
A step of creating a map information representing a relative positional relationship between the plurality of landmark devices while arranging a plurality of landmark devices in advance by the map creating method according to claim 4;
A user designates an identifier of any one landmark device as a goal point for the robot;
The robot acquires map information from the nearest landmark device by optical wireless communication,
Based on the acquired map information and the identifier of the landmark device designated as the goal point, the robot tracks the order of the landmark device from the nearest landmark device to the landmark device designated as the goal point. Calculating as a route;
A method for determining a movement path of a robot.

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