JP7477426B2 - Navigation device, navigation method, and computer program - Google Patents

Description

The present invention relates to a navigation device, a navigation method, and a computer program.

In recent years, technology has been developed to remotely control autonomously moving robots via wireless communication. For example, Patent Document 1 describes an autonomously moving robot that, when it detects an obstacle in its path of movement, determines whether to continue autonomous movement or switch to remote control, and when switching from autonomous movement to remote control, transmits a signal to an external terminal prompting remote control and receives a signal from the external terminal instructing remote control.

JP 2013-206237 A

However, with the conventional technology described above, if the wireless communication between the autonomous robot and the external terminal is cut off or interrupted when switching from autonomous driving to remote control, the autonomous robot cannot be smoothly remotely controlled. Furthermore, when remotely controlling a robot, it is desirable to ensure communication quality that allows the robot to be remotely controlled without any problems.

The present invention was made in consideration of these circumstances, and its purpose is to achieve stable remote control of a moving object via wireless communication.

(1) One aspect of the present invention is a navigation device that provides route information indicating a route from a departure point to a destination for a mobile body that is remotely controlled via a wireless communication line, and includes a position communication quality storage unit that stores position communication quality information in which a position and communication quality at the position are associated and recorded, an acceptable quality determination unit that determines an acceptable quality, which is a communication quality that is acceptable for communication related to remote control, a cost calculation unit that calculates a cost related to movement of the mobile body when communication quality is not taken into consideration for the candidate route based on the acceptable quality and the position communication quality information stored in the position communication quality storage unit, and if the communication quality does not satisfy the acceptable quality, adds a larger value to the calculated cost based on the acceptable quality and the position communication quality information stored in the position communication quality storage unit, and calculates an overall link cost that is the result of the addition , and a route search unit that searches for the route from among the candidate routes based on the calculated overall link cost .
(2) One aspect of the present invention is the navigation device of (1) above, in which the acceptable quality determination unit determines the acceptable quality for the candidate routes based on at least one of road information, outdoor population density, the type of the moving body, and the contents of remote control of the moving body.
(3) One aspect of the present invention is the navigation device of (2) above, wherein the acceptable quality determination unit sets the acceptable quality to a higher communication quality the narrower the road is or the more people are concentrated on the road .
(4) One aspect of the present invention is the navigation device according to any one of (1) to (3) above, wherein the acceptable quality determination unit determines the acceptable quality based on an operation skill level of a remote operator.
(5) One aspect of the present invention is the navigation device described above in (4), further comprising an operator assignment unit that assigns to the mobile body a remote operator having an operation skill level different from the operation skill level of the remote operator assigned to the mobile body based on the result of the judgment of the acceptable quality.
(6) One aspect of the present invention is a navigation device of any of (1) to (5) above, wherein the communication quality is at least one of throughput, delay, jitter, and packet loss in each of the directions in which the mobile device transmits and receives data.
(7) One aspect of the present invention is the navigation device of any of (1) to (6) above, wherein the moving body is a robot that switches between an autonomous mode in which the moving body moves autonomously and a remote control mode in which the moving body moves according to remote control in accordance with instructions received via a wireless communication line.

(8) One aspect of the present invention is a navigation method for providing route information indicating a route from a departure point to a destination to a mobile body that is remotely controlled via a wireless communication line, the navigation method including: a position communication quality storage step of storing position communication quality information, in which a position and communication quality at the position are associated and recorded, in a position communication quality storage unit; an acceptable quality determination step of determining an acceptable quality, which is communication quality that is acceptable for communication related to remote control; a cost calculation step of calculating a cost related to movement of the mobile body when communication quality is not taken into consideration for the candidate route, and, based on the acceptable quality and the position communication quality information stored in the position communication quality storage unit , if the communication quality does not satisfy the acceptable quality, adding a larger value to the calculated cost based on the acceptable quality and the position communication quality information stored in the position communication quality storage unit, and calculating an overall link cost that is the result of the addition; and a route search step of searching for the route from among the candidate route based on the calculated overall link cost .

(9) One aspect of the present invention is a computer program for causing a computer of a navigation device that provides route information indicating a route from a starting point to a destination to a mobile body that is remotely controlled via a wireless communication line to execute the following steps: a position communication quality storage step of storing position communication quality information in a position communication quality storage unit, the position and the communication quality at the position being associated and recorded; an acceptable quality determination step of determining an acceptable quality , which is a communication quality that is acceptable for communication related to remote control; a cost calculation step of calculating a cost related to movement of the mobile body when communication quality is not taken into consideration for the candidate route based on the acceptable quality and the position communication quality information stored in the position communication quality storage unit , and, if the communication quality does not satisfy the acceptable quality, adding a larger value to the calculated cost based on the acceptable quality and the position communication quality information stored in the position communication quality storage unit, and calculating an overall link cost that is the result of the addition; and a route search step of searching for the route from among the candidate route based on the calculated overall link cost .

The present invention has the effect of realizing stable remote control of a moving object via wireless communication.

1 is a block diagram showing an example of the configuration of a navigation system according to an embodiment; 11 is a diagram illustrating an example of the configuration of a position and communication quality storage unit according to an embodiment; 1 is a flowchart illustrating an example of a procedure of a navigation method according to an embodiment. FIG. 11 is an explanatory diagram for explaining an example of a route search method. FIG. 2 is an explanatory diagram for explaining a route search method according to an embodiment;

The following describes an embodiment of the present invention with reference to the drawings. In this embodiment, a navigation system in a delivery service system that uses autonomously moving robots (hereinafter referred to as mobile robots) to make deliveries is used as an example.

Fig. 1 is a block diagram showing an example of the configuration of a navigation system 10 according to an embodiment. In Fig. 1, a mobile robot 2 communicates with a navigation device 4 via a wireless communication line. The mobile robot 2 is an example of a moving body. The navigation device 4 provides the mobile robot 2 with route information indicating a route from a starting point to a destination.

The navigation device 4 according to this embodiment has a remote monitoring and operation function in addition to the navigation function. Note that the remote monitoring and operation function may be provided by a device other than the navigation device 4 that is external to the mobile robot 2.

The navigation device 4 uses a remote monitoring and operation function to remotely monitor and operate the mobile robot 2 via wireless communication. For example, the navigation device 4 receives images captured by the mobile robot 2 and sounds picked up by the mobile robot 2 via a wireless communication line, and displays and plays the received images and sounds. By viewing the images and sounds, a monitor can monitor the movement status of the mobile robot 2 in real time. In addition, a remote operator who remotely operates the mobile robot 2 can recognize the movement status of the mobile robot 2 in real time by viewing the images and sounds, and remotely operate the mobile robot 2.

The navigation device 4 also transmits, via wireless communication, to the mobile robot 2 a remote control switch command to switch from the autonomous mode to the remote control mode and a remote control cancel command to cancel the remote control mode. The autonomous mode is an operation mode in which the mobile robot 2 moves autonomously. The remote control mode is an operation mode in which the mobile robot 2 moves according to remote control.

When the mobile robot 2 receives a remote control switching command from the navigation device 4 via wireless communication, it switches its operation mode from the autonomous mode to the remote control mode, and thereafter moves according to remote control. When the mobile robot 2 receives a remote control release command from the navigation device 4 via wireless communication, it switches its operation mode from the remote control mode to the autonomous mode, and thereafter moves autonomously.

As described above, in the delivery service system according to this embodiment, the mobile robot 2 is monitored and operated remotely via wireless communication. For this reason, it is required to achieve stable wireless communication in the mobile robot 2. By achieving stable wireless communication in the mobile robot 2, it is possible to achieve stable remote operation of the mobile robot 2 via wireless communication. Therefore, in this embodiment, the navigation device 4 provides route information for achieving stable wireless communication in the mobile robot 2. Furthermore, the navigation device 4 provides route information that contributes to achieving stable remote operation of the mobile robot 2.

The configuration of the navigation system 10 according to this embodiment will be described below with reference to FIG. 1.

[User terminal]
The user terminal 1 is a terminal used by a user of the delivery service system according to this embodiment (hereinafter referred to as a delivery service user). The delivery service user requests delivery by specifying a destination to which a package is to be delivered. The user terminal 1 may be a mobile communication terminal device such as a smartphone or a tablet computer (tablet PC), or may be a stationary communication terminal device (e.g., a stationary personal computer).

The user terminal 1 includes a product ordering unit 101 and a destination information input unit 102. The product ordering unit 101 selects a product and places an order for the selected product in response to operations performed by the delivery service user.

The product ordering unit 101 may manage the remaining quantity of goods owned by the delivery service user in real time, and automatically order replenishment goods when the remaining quantity of goods falls below a preset threshold.

The destination information input unit 102 inputs destination information indicating the destination, such as an address, when the product ordering unit 101 orders a product. The destination information may be specified by the delivery service user each time, or the destination information input unit 102 may record destination information previously specified by the delivery service user and automatically reuse the recorded destination information.

The destination information input unit 102 may use a positioning function of the GPS (Global Positioning System) provided in the user terminal 1 to set the current location acquired by the GPS as the destination. The destination information input unit 102 may also add an image of the scenery around the user terminal 1 captured by a camera of the user terminal 1 to the destination information as reference information for the destination.

[Mobile robot]
The mobile robot 2 is a robot capable of autonomous travel. The mobile robot 2 travels, for example, within a city and delivers packages to destinations designated by delivery service users.

The mobile robot 2 includes a current position acquisition unit 201, a status acquisition unit 202, a wireless communication unit 203, a route information storage unit 204, an imaging unit 205, an operation determination unit 206, an operation control unit 207, a remote operation switching unit 208, and a remote operation unit 209.

The current position acquisition unit 201 acquires the current position (position information) using a positioning system such as GPS. The status acquisition unit 202 acquires status data (status information) such as the remaining battery level, temperature, and movement speed from various sensors equipped in the mobile robot 2.

The wireless communication unit 203 performs wireless communication with the navigation device 4. The wireless communication unit 203 supports wireless communication methods such as LTE (Long Term Evolution) and 5G (fifth generation mobile communication system), and performs wireless communication via a base station of the wireless communication method that it supports. The wireless communication unit 203 may also support an unlicensed wireless communication method such as Wi-Fi (registered trademark), and perform wireless communication using the unlicensed wireless communication method.

The wireless communication unit 203 transmits information obtained by the current position acquisition unit 201, the status acquisition unit 202, and the imaging unit 205 to the operation monitoring unit 401 of the navigation device 4. The wireless communication unit 203 also receives route information transmitted from the route distribution unit 417 of the navigation device 4 and stores it in the route information storage unit 204. The route information stored in the route information storage unit 204 is used to determine the operation of the mobile robot 2.

The wireless communication unit 203 transmits the remote operation switching command received from the remote operation command issuing unit 419 of the navigation device 4 to the remote operation switching unit 208. The remote operation switching unit 208 switches the operation mode of the mobile robot 2 from the autonomous mode to the remote operation mode in accordance with the remote operation switching command. The wireless communication unit 203 transmits the remote operation command received from the remote operation command issuing unit 419 of the navigation device 4 to the remote operation unit 209. The remote operation command is transmitted from the remote operation command issuing unit 419 of the navigation device 4 in response to the operation of the remote operator. Examples of remote operation commands include forward, backward, right turn, left turn, etc. In the remote operation mode, the remote operation unit 209 controls the operation control unit 207 in response to the remote operation command.

The wireless communication unit 203 transmits the remote control release command received from the remote control command issuing unit 419 of the navigation device 4 to the remote control switching unit 208. The remote control switching unit 208 switches the operation mode of the mobile robot 2 from the remote control mode to the autonomous mode in accordance with the remote control release command.

The imaging unit 205 captures an image of the traveling direction of the mobile robot 2. In the remote operation mode, the imaging unit 205 transmits the captured image in real time to the navigation device 4 via the wireless communication unit 203. This is because, in the remote operation mode, the remote operator operates the mobile robot 2 while viewing the image captured by the imaging unit 205.

The operation determination unit 206 determines the next operation of the mobile robot 2. When moving along a route indicated by the route information stored in the route information storage unit 204, the operation determination unit 206 determines an operation suited to the surrounding environment of the mobile robot 2 using the current position acquired by the current position acquisition unit 201, the captured image captured by the imaging unit 205, etc.

The operation control unit 207 causes the mobile robot 2 to execute the operation determined by the operation determination unit 206. However, in the remote control mode, the mobile robot 2 executes an operation according to the control by the remote control unit 209. The operation control unit 207 controls the traveling type and traveling speed of the mobile robot 2, such as moving forward, backward, turning right or left, and the type of operation other than traveling, such as changing the imaging direction of the imaging unit 205.

[Mobile devices]
The mobile terminal 3 is a mobile communication terminal device such as a smartphone or a tablet PC. The mobile terminal 3 may be used as the user terminal 1, or may be separate from the user terminal 1. For example, the mobile terminal 3 may be the mobile terminals of all subscribers who have subscribed to a specific wireless communication carrier and have agreed to obtain location information with the wireless communication carrier.

The mobile terminal 3 periodically reports its current location (location information) and the communication quality (communication quality information) at the current location to the navigation device 4 for each wireless communication method and wireless frequency band that it supports.

[Navigation device]
The navigation device 4 navigates one or more mobile robots 2 from a starting point to a destination. The navigation device 4 also remotely monitors and operates one or more mobile robots 2.

The navigation device 4 includes an operation monitoring unit 401, an operation information storage unit 402, a communication quality acquisition unit 403, a position/communication quality storage unit 404, a map information storage unit 405, a mobile terminal position information storage unit 406, an outdoor population density estimation unit 407, a travel cost calculation unit 408, an order information storage unit 409, a destination acquisition unit 410, a robot information storage unit 411, an operation content storage unit 412, an operator skill information storage unit 413, an operator allocation unit 414, an acceptable quality determination unit 415, a route search unit 416, a route distribution unit 417, a remote operation implementation determination unit 418, and a remote operation command issuing unit 419.

The functions of the navigation device 4 are realized by the navigation device 4 being equipped with computer hardware such as a CPU (Central Processing Unit) and memory, and the CPU executing a computer program stored in the memory. The navigation device 4 may be configured using a general-purpose computer device, or may be configured as a dedicated hardware device. For example, the navigation device 4 may be configured using a server computer connected to a communication network such as the Internet. The functions of the navigation device 4 may be realized by cloud computing. The navigation device 4 may be realized by a single computer, or may be realized by distributing the functions of the navigation device 4 among multiple computers. The navigation device 4 may also be configured to set up a website using, for example, a WWW system.

The operation monitoring unit 401 performs operation monitoring of one or more mobile robots 2. The operation monitoring unit 401 performs operation monitoring by associating position information and status information received in real time from the mobile robot 2 with information identifying the individual mobile robot 2 (mobile robot ID). The operation monitoring unit 401 performs operation monitoring based on information (position information and status information) that is updated periodically, for example, at one-second intervals. The operation monitoring unit 401 analyzes the position information and status information received from the mobile robot 2, and if a fault is detected in the mobile robot 2, it issues an alarm, for example, to a supervisor. The operation information storage unit 402 stores the information (position information and status information) that the operation monitoring unit 401 receives from the mobile robot 2 in order to investigate the cause of the fault and to consider future countermeasures.

The communication quality acquisition unit 403 acquires communication quality information indicating the communication quality of the communication performed between the navigation device 4 and the mobile robot 2 via a wireless communication line. The communication quality acquisition unit 403 acquires the communication quality (communication quality information) when the mobile robot 2 (wireless communication unit 203) performs wireless communication with the navigation device 4 for each wireless communication method and wireless frequency band supported by the mobile robot 2 (wireless communication unit 203).

The communication quality information is, for example, information indicating the throughput, delay, jitter, packet loss, etc. in each of the directions in which the mobile robot 2 transmits data (upstream direction) and receives data (downstream direction). The communication quality information may be information indicating at least one of the throughput, delay, jitter, and packet loss in each of the upstream direction and downstream direction.

When the remote operator is remotely operating the mobile robot 2, high-speed, large-volume video is transmitted from the mobile robot 2, so the communication quality acquisition unit 403 can acquire the throughput, delay, jitter, and packet loss as communication quality information. On the other hand, when the mobile robot 2 is moving autonomously in the autonomous mode, only low-speed, small-volume position information and status information is transmitted from the mobile robot 2, so the communication quality acquisition unit 403 can acquire only the delay and jitter as communication quality information.

The location and communication quality storage unit 404 stores location and communication quality information in which location information and communication quality information are associated and recorded for each wireless communication method and wireless frequency band. Location and communication quality information may be provided for each date, day of the week, time period, and event. For example, location and communication quality information for weekdays (Monday to Friday) and location and communication quality information for holidays (Saturday, Sunday, and public holidays) may be provided. For example, location and communication quality information for daytime hours and location and communication quality information for nighttime hours may be provided. For example, location and communication quality information for New Year's Day, Golden Week, and Obon may be provided.

Fig. 2 is a diagram showing an example of the configuration of the position/communication quality storage unit 404 according to this embodiment. In the example of Fig. 2, the position/communication quality storage unit 404 stores, for the wireless communication method "LTE", position/communication quality information 4041 of wireless frequency band LTE_a and position/communication quality information 4042 of wireless frequency band LTE_b. In addition, for the wireless communication method "5G", the position/communication quality storage unit 404 stores, for example, position/communication quality information 4043 of wireless frequency band 5G_a and position/communication quality information 4044 of wireless frequency band 5G_b.

LTE uses radio frequency bands such as Band 1 (2.1 GHz) and Band 18 (800 MHz). 5G uses radio frequency bands such as the 28 GHz band.

For example, the position communication quality information 4041 is information in which communication quality LTE_a_a, communication quality LTE_a_b, ... at each position _a, position _b, ... of the radio frequency band LTE_a of the wireless communication method "LTE" are associated and recorded. For example, the position communication quality information 4043 is information in which communication quality 5G_a_a, communication quality 5G_a_b, ... at each position _a, position _b, ... of the radio frequency band 5G_a of the wireless communication method "5G" are associated and recorded.

The position information and communication quality information recorded in the position communication quality information are the communication quality information acquired by the communication quality acquisition unit 403 and the current position (position information) of the mobile robot 2 at the time of acquisition. Note that position information and communication quality information measured by other devices, such as the mobile terminal 3, other than the communication quality acquisition unit 403 may also be recorded in the position communication quality information.

The location information is, for example, GPS coordinates. For indoor facilities where GPS coordinates cannot be obtained, absolute location information obtained by indoor positioning technology such as IMES (Indoor MEssaging System) may be used as the location information. The communication quality information is information indicating at least one of the throughput, delay, jitter, and packet loss in each of the uplink and downlink directions.

The map information storage unit 405 stores nationwide road map data and associated facility data such as various facilities and shops. The road map data is provided as link data in which roads on a map are divided into multiple parts with intersections and the like as nodes, and the parts between each node are defined as links. This link data includes data such as a link-specific identifier (link ID), link length, position information (longitude, latitude) of the start and end points (nodes) of the link, angle (direction) data, road width, and road type. The road map data may also include lane information indicating lanes that the mobile robot 2 can travel. The map information storage unit 405 may also store indoor map data.

The mobile terminal location information storage unit 406 stores the history of location information for each mobile terminal 3. For example, it stores the GPS coordinates of each mobile terminal 3 in association with the time.

The outdoor population density estimation unit 407 determines whether each mobile terminal 3 was indoors or outdoors based on the history of location information stored in the mobile terminal location information storage unit 406, and estimates the outdoor population density for each pre-set area based on this determination result. The outdoor population density is the number of people per unit area outdoors. The outdoor population density calculated by the outdoor population density estimation unit 407 is stored in the map information storage unit 405 in association with the corresponding link data in the road map data of the map information storage unit 405.

For example, the outdoor population density estimation unit 407 determines that a mobile terminal 3 was indoors if the change in location information is less than a certain amount and is judged to have changed very little, and determines that the mobile terminal 3 was outdoors if the change in the location information is greater than a certain amount and is judged to have changed to some extent.

The outdoor population density estimation unit 407 may also perform map matching by comparing the location information of each mobile terminal 3 with road map data stored in the map information storage unit 405, and estimate that the mobile terminal 3 was using a road. Map matching is a process in which location information obtained by GPS, which may contain errors, is corrected using map information to place the location on a road. Map matching is used, for example, in car navigation systems.

The outdoor population density estimation unit 407 may also determine whether the means of transportation of the mobile terminal 3 is walking or a vehicle based on the movement speed of the mobile terminal 3.

The outdoor population density estimation unit 407 may estimate the outdoor population density for each month, day of the week, and time period. This is because the outdoor population density may vary significantly depending on the month, day of the week, time period, etc., even in the same area.

The outdoor population density estimation unit 407 may also estimate the outdoor population density using a method other than the method using the location information of the mobile terminal 3. For example, the outdoor population density estimation unit 407 may use video captured by the mobile robot 2 and estimate the outdoor population density based on the results of image recognition of people in the captured video.

The travel cost calculation unit 408 calculates an overall link cost for each link of each road for each wireless communication method and wireless frequency band based on the information stored in the map information storage unit 405, the position and communication quality information stored in the position and communication quality storage unit 404, and the result of the acceptable quality judgment by the acceptable quality judgment unit 415 described later. The travel cost calculation unit 408 calculates an overall link cost based on at least the position and communication quality information stored in the position and communication quality storage unit 404 and the result of the acceptable quality judgment by the acceptable quality judgment unit 415. The overall link cost calculated by the travel cost calculation unit 408 is stored in the map information storage unit 405 in association with the corresponding link data in the road map data of the map information storage unit 405.

The acceptable quality refers to the communication quality that is acceptable for communication related to remote control. In this embodiment, the acceptable quality is the communication quality that is acceptable for communication related to remote control of the mobile robot 2.

The travel cost calculation unit 408 weights each link of each road based on the result of the judgment of the acceptable quality by the acceptable quality judgment unit 415 and the position and communication quality information stored in the position and communication quality storage unit 404 so that if the communication quality does not satisfy the judgment result of the acceptable quality, it will be evaluated low. For example, the travel cost calculation unit 408 may weight the links of a road whose communication quality recorded in the position and communication quality information is determined not to satisfy the judgment result of the acceptable quality so that the total link cost is the largest.

The route search unit 416, which will be described later, sequentially calculates (accumulates) the cost of the roads (links) from the starting point to the destination to the next reachable intersection (node), and selects the route from the starting point to the destination with the smallest cost. Therefore, if a small total link cost value is set for a road, that road is more likely to be selected as a route. On the other hand, if a large total link cost value is set for a road, that road is less likely to be selected as a route, and even more so, that road is not selected as a route. For this reason, by weighting each link of each road so that a link whose communication quality does not satisfy the judgment result of the acceptable quality is evaluated low, a link whose communication quality does not satisfy the judgment result of the acceptable quality is less likely to be selected as a route, and even more so, a link whose communication quality does not satisfy the judgment result of the acceptable quality is not selected as a route, so that route information that contributes to realizing stable remote operation of the mobile robot 2 can be provided.

The movement cost calculation unit 408 may also calculate the overall link cost based on the outdoor population density. The movement cost calculation unit 408 may weight the links of roads where the outdoor population density is equal to or greater than a threshold value so that the overall link cost is large. This allows the mobile robot 2 to travel on roads with fewer people.

The movement cost calculation unit 408 may also calculate the total link cost based on at least one of the type of the mobile robot 2 and the contents of the delivery by the mobile robot 2, and the road conditions of each link of each road. The type of the mobile robot 2 is classified according to the size, structure, etc. of the mobile robot 2. The type of the mobile robot 2 is also classified according to the wireless communication method and wireless frequency band that the mobile robot 2 can use. The contents of the delivery by the mobile robot 2 are, for example, the type of cargo delivered by the mobile robot 2 and the expected load amount.

For example, the movement cost calculation unit 408 does not increase the total link cost for links of roads with a width less than the threshold value because a small mobile robot 2 can travel safely, but increases the total link cost for a large mobile robot 2. Also, since it is assumed that depending on the structure of the mobile robot 2, it may be difficult for the robot 2 to overcome steps in the road, the movement cost calculation unit 408 increases the total link cost for links of roads with steps for the relevant type of mobile robot 2. Also, when the type of cargo delivered by the mobile robot 2 is fragile, it is preferable for the robot 2 to travel on roads with few bumps, so the movement cost calculation unit 408 decreases the total link cost of links of roads with few bumps, but increases the total link cost of links of roads with many bumps.

The travel cost calculation unit 408 may also use evaluation factors used in known navigation systems as information used to calculate the overall link cost. Evaluation factors used in known navigation systems include, for example, the required distance of the link, the required time for travel, weighting based on road conditions and road width, weighting based on the frequency of traffic lights, weighting based on congestion tendency, etc.

The order information storage unit 409 receives order information for ordering products from the user terminal 1 and stores the received order information. The order information storage unit 409 works in conjunction with a purchasing system (not shown) to process purchases and formulate a product delivery plan. The order information storage unit 409 stores planned delivery information such as the departure point, destination, and time period for the mobile robot 2 to deliver the products according to the formulated product delivery plan. The destination acquisition unit 410 acquires destination information from the order information stored in the order information storage unit 409.

The robot information storage unit 411 stores information indicating the type of each mobile robot 2. The operation content storage unit 412 stores information indicating the content of remote operation of each mobile robot 2. The content of remote operation of the mobile robot 2 includes, for example, running such as moving forward and turning right and left, and operating the robot arm. The operator skill information storage unit 413 stores information (operation skill information) indicating the level of remote operation skill (operation skill level) of the mobile robot 2 possessed by each remote operation candidate registered as a candidate for a remote operator who will remotely operate the mobile robot 2.

The operator allocation unit 414 assigns a remote operator having an operation skill level different from that of the remote operator assigned to the mobile robot 2 to the mobile robot 2 based on the operation skill information stored in the operator skill information storage unit 413 and the degree of satisfaction with the result of the judgment of the acceptable quality by the acceptable quality judgment unit 415 described later. The degree of satisfaction with the judgment result of the acceptable quality is the degree to which the communication quality of each link of each road satisfies the judgment result of the acceptable quality. For example, if it is determined that it is difficult to secure a route that satisfies the acceptable quality because the satisfaction with the judgment result of the acceptable quality is low, an attempt is made to secure a route that satisfies the acceptable quality by changing to a remote operator with a higher operation skill level and relaxing the acceptable quality. On the other hand, if it is determined that it is easy to secure a route that satisfies the acceptable quality because the satisfaction with the judgment result of the acceptable quality is high, the remote operator may be changed to a remote operator with a lower operation skill level on the condition that the judgment result of the acceptable quality is satisfied.

The acceptable quality determination unit 415 determines the acceptable quality for the product delivery plan formulated by the order information storage unit 409. The acceptable quality determination unit 415 determines the acceptable quality for the candidate routes from the starting point to the destination in the product delivery plan based on at least one of road information, outdoor population density, the type of mobile robot 2, and the content of remote control of the mobile robot 2. Furthermore, the acceptable quality determination unit 415 determines the acceptable quality based on the operating skill level of the remote operator.

The acceptable quality determination unit 415 determines the acceptable quality based on the road information stored in the map information storage unit 405 for candidate delivery routes assumed in the delivery order in the product delivery plan. For example, the acceptable quality determination unit 415 sets stricter conditions for determining the acceptable quality and imposes higher communication quality the narrower the road width. This is because the narrower the road width, the shorter and stricter the communication delay that is allowed for the mobile robot 2 to avoid people and obstacles.

The acceptable quality determination unit 415 determines the acceptable quality based on the outdoor population density information stored in the map information storage unit 405 for candidate delivery routes assumed in the delivery order in the product delivery plan. For example, the acceptable quality determination unit 415 sets stricter judgment conditions for the acceptable quality and imposes higher communication quality the more densely people are on the road. This is because the more densely people are on the road, the shorter and stricter the communication delay that is allowed for the mobile robot 2 to avoid people and obstacles becomes.

The acceptable quality determination unit 415 determines the acceptable quality based on information on the type of mobile robot 2 stored in the robot information storage unit 411 selected in the delivery order in the product delivery plan. For example, the acceptable quality determination unit 415 sets stricter judgment conditions for the acceptable quality and imposes higher communication quality the faster the moving speed of the mobile robot 2. This is because the faster the moving speed of the mobile robot 2, the shorter and stricter the communication delay that is allowed for the mobile robot 2 to avoid people and obstacles. For example, the acceptable quality determination unit 415 sets stricter judgment conditions for the acceptable quality and imposes higher communication quality the larger the size of the mobile robot 2. This is because the larger the size of the mobile robot 2, the shorter and stricter the communication delay that is allowed for the mobile robot 2 to avoid people and obstacles.

The acceptable quality determination unit 415 determines the acceptable quality based on information on the content of remote operation of the mobile robot 2 stored in the operation content storage unit 412 that is assumed in the delivery order in the product delivery plan. For example, when the content of remote operation of the mobile robot 2 includes complex operations such as operating a robot arm, the acceptable quality determination unit 415 tightens the judgment conditions for the acceptable quality and imposes higher communication quality. This is because when complex operations such as operating a robot arm are performed remotely, the acceptable communication delay becomes shorter and stricter.

The acceptable quality determination unit 415 determines the acceptable quality based on the operation skill information stored in the operator skill information storage unit 413 of the remote operator selected in the delivery order in the product delivery plan. For example, the acceptable quality determination unit 415 sets stricter judgment conditions for the acceptable quality and imposes higher communication quality the lower the operation skill level of the remote operator. This is because the lower the operation skill level of the remote operator, the shorter and stricter the communication delay permitted for remote operation of the mobile robot 2 becomes.

In this embodiment, the acceptable quality is calculated as follows: throughput "xx Mbps or more", delay "xx ms or less", jitter "△△ ms or less", and packet loss "□□% or less". Throughput and packet loss affect the playback quality when the remote operator watches the video transmitted from the mobile robot 2. Delay affects the instantaneity of remote operation. Jitter affects the prediction accuracy when the remote operator predicts the movement of the mobile robot 2 and performs remote operation. The acceptable quality of each item is calculated based on the characteristics of each of these items (throughput, delay, jitter, packet loss). For example, an acceptable quality selection table in which the acceptable range of each item (throughput, delay, jitter, packet loss) is associated with each of the above-mentioned parameters (road information, outdoor population density, type of mobile robot 2, content of remote operation of the mobile robot 2, operation skill level of the remote operator) may be created in advance, and the acceptable quality determination unit 415 may calculate the acceptable range of each item using the acceptable quality selection table. The acceptable quality selection table may be created by parameterizing the surrounding environment and circumstances at the time of actual remote operation communication quality, and using the results of a subjective evaluation of whether or not remote operation was smooth.

As another method of calculating the acceptable quality, a machine learning model may be generated using machine learning to derive environments and situations in which smooth remote operation can be performed when a subjective evaluation result indicates that smooth remote operation can be performed in a certain environment or situation, and the acceptable quality may be calculated using the machine learning model.

The route search unit 416 searches for a route from the starting point of the mobile robot 2 to the destination as the planned route along which the mobile robot 2 will travel, based on the total link cost calculated by the movement cost calculation unit 408. The destination of the mobile robot 2 is the location indicated by the destination information acquired from the order information by the destination acquisition unit 410. The starting point of the mobile robot 2 is set in advance. For example, a product delivery base (e.g., a logistics warehouse where the product is stored or a delivery store nearest to the destination) is set in advance as the starting point of the mobile robot 2. In addition, when the mobile robot 2 is transported to the vicinity of the destination by a vehicle, the location of the delivery destination of the mobile robot 2 is set in advance as the starting point of the mobile robot 2.

The route search unit 416 can use, for example, the Dijkstra algorithm, the A* algorithm, or a genetic algorithm as a route search method.

The route distribution unit 417 transmits route information indicating the route searched by the route search unit 416 to the mobile robot 2.

The remote operation execution determination unit 418 uses the information acquired by the operation monitoring unit 401 to determine whether or not to execute remote operation. For example, when the mobile robot 2 is in a crowded place and is stuck and unable to move autonomously, the remote operation execution determination unit 418 determines to switch to remote operation. In addition, when the mobile robot 2 is in a situation where it can move autonomously by remote control, the remote operation execution determination unit 418 determines to cancel remote operation.

The remote operation command issuing unit 419 transmits a remote operation switching command to the mobile robot 2 when the remote operation execution determining unit 418 determines to switch to remote operation. In addition, the remote operation command issuing unit 419 transmits a remote operation release command to the mobile robot 2 when the remote operation execution determining unit 418 determines to release the remote operation.

Next, the navigation method according to this embodiment will be described with reference to FIG. 3. FIG. 3 is a flowchart showing an example of the procedure of the navigation method according to this embodiment.

(Step S1) The route search unit 416 acquires the starting point from which the mobile robot 2 starts traveling and the destination to which the mobile robot 2 travels in the product delivery plan formulated by the order information storage unit 409.

(Step S2) The route search unit 416 acquires the type of mobile robot 2 and the delivery details.

(Step S3) The route search unit 416 recognizes the wireless communication method and wireless frequency band that can be used by the mobile robot 2 from the type of the mobile robot 2 acquired in step S2. The correspondence between the type of the mobile robot 2 and the available wireless communication method and wireless frequency band is set in advance in the navigation device 4.

(Step S4) The acceptable quality determination unit 415 determines the acceptable quality of the candidate routes from the departure point to the destination acquired by the route search unit 416 based on the corresponding product delivery plan.

(Step S5) The route search unit 416 instructs the movement cost calculation unit 408 to specify a search range including the starting point and destination of the mobile robot 2 acquired in step S1 and link cost calculation conditions, and to calculate the total link cost of each link of each road within the search range. The link cost calculation conditions include the type of mobile robot 2, the content of the delivery, the available wireless communication method and wireless frequency band, etc.

In response to an instruction to calculate the total link cost from the route search unit 416, the movement cost calculation unit 408 calculates the total link cost for each link of each road within the search range for each wireless communication method and wireless frequency band. In calculating the total link cost, weighting is applied to each link of each road so that if the communication quality does not satisfy the result of the judgment of the acceptable quality in step S4, the link is rated low. The movement cost calculation unit 408 stores the calculated total link cost in the map information storage unit 405 in association with the corresponding link data in the road map data in the map information storage unit 405. Note that, when there are multiple wireless communication methods and wireless frequency bands available to the mobile robot 2, the movement cost calculation unit 408 may store the total link cost for the wireless communication method and wireless frequency band that provide the best communication quality for each link of each road in association with the corresponding link data in the map information storage unit 405.

The travel cost calculation unit 408 responds to the route search unit 416 to notify it that the total link cost has been calculated.

(Step S6) The route search unit 416 searches for a route from the starting point to the destination of the mobile robot 2 acquired in step S1, based on the total link cost calculated by the movement cost calculation unit 408 in step S5. In this route search, a route is searched for that minimizes the sum of the total link costs of each link traversed from the starting point to the destination.

(Step S7) The route distribution unit 417 transmits route information indicating the route searched for in step S6 to the mobile robot 2.

Figure 4 is an explanatory diagram for explaining an example of a route search method. Figure 5 is an explanatory diagram for explaining a route search method according to this embodiment. In Figures 4 and 5, circles indicate nodes, and lines connecting nodes indicate links. The starting node is S, and the destination node is G. Numbers written on links indicate link costs. Figure 4 shows link costs when communication quality is not taken into consideration. On the other hand, Figure 5 shows total link costs when communication quality is taken into consideration and according to this embodiment. In Figure 5, for each link, a delay of acceptable quality (acceptable delay) and an estimated delay (estimated delay) are shown for delay, which is an example of communication quality. The estimated delay is a value based on the position and communication quality information stored in the position and communication quality storage unit 404. Here, it is assumed that the communication quality of link L2 does not meet the acceptable quality, and there is a high possibility that communication quality that allows the mobile robot 2 to be remotely operated without problems will not be ensured.

In the case of the link costs in FIG. 4, as a result of the route search, "L1 → L2 → L3" is selected as the route from the starting point "node S" to the destination "node G", as this is the route with the smallest total link cost. Since the link costs in FIG. 4 do not take communication quality into consideration, link L2 is selected as the route, which is unlikely to ensure the communication quality required to remotely control the mobile robot 2 without any problems. As a result, if the communication quality between the mobile robot 2 and the navigation device 4 on the selected route becomes insufficient for remotely controlling the mobile robot 2, it may become impossible to smoothly remotely control the mobile robot 2.

On the other hand, in FIG. 5, the estimated delay in link L2 does not satisfy the allowable delay, so a total link cost of "4+10" is set for link L2, which is the additional link cost of "+10" added to the link cost of "4" in FIG. 4. The additional link cost is set to "0" if the estimated communication quality satisfies the allowable quality. On the other hand, the larger the degree to which the estimated communication quality does not satisfy the allowable quality, the larger the "positive value" is set for the additional link cost. The estimated delay satisfies the allowable delay for the other links other than link L2, so the additional link cost is set to "0". As a result, according to the total link cost in FIG. 5, link L2, which is likely to not ensure communication quality that allows the mobile robot 2 to be remotely operated without problems, is not selected as a route. Then, in the case of the link cost in FIG. 5, as a result of the route search, "L4→L5", which is the route with the smallest total link cost, is selected as the route to reach the destination "node G" from the starting point "node S". According to this selected route "L4→L5", it is possible to ensure communication quality that allows the mobile robot 2 to be remotely operated without problems. This makes it possible to achieve stable remote control of the mobile robot 2 via wireless communication.

When the destination cannot be reached from the departure point without passing through a link that is highly unlikely to ensure the communication quality required for remotely operating the mobile robot 2 without any problems, the operator allocation unit 414 assigns to the mobile robot 2 a remote operator having a different operation skill level that is higher than the operation skill level of the remote operator assigned to the mobile robot 2. This relaxes the allowable quality, thereby attempting to ensure a route that satisfies the allowable quality.

If this attempt fails to secure a route that satisfies the acceptable quality, a link that is unlikely to ensure the communication quality required to remotely operate the mobile robot 2 without problems may be selected as the route from the departure point to the destination. If the route search unit 416 finds a link in the route as a result of the search that is unlikely to ensure the communication quality required to remotely operate the mobile robot 2 without problems, it outputs alert information indicating that link. This alert information allows the remote operator to recognize in advance locations where it is unlikely to ensure the communication quality required to remotely operate the mobile robot 2 without problems.

According to the above-described embodiment, it is possible to provide route information for realizing stable wireless communication in the mobile robot 2, and further to provide route information that contributes to realizing stable remote control of the mobile robot 2. This provides the effect of realizing stable remote control when remotely controlling the mobile robot 2 via wireless communication.

The above describes an embodiment of the present invention in detail with reference to the drawings, but the specific configuration is not limited to this embodiment, and includes design modifications and the like that do not deviate from the gist of the present invention.

In the above-described embodiment, the navigation system is applied to a delivery service system, but it may also be applied to systems other than delivery service systems. For example, the navigation system according to the above-described embodiment may be applied to a road inspection service system that inspects roads using a mobile robot.

In the above-described embodiment, a mobile robot is given as an example of a mobile body, but the present invention is not limited to this. A vehicle that performs automatic driving (automatic driving vehicle), an air vehicle that flies autonomously, etc. may also be used as a mobile body.

In addition, a computer program for implementing the functions of each of the above-mentioned devices may be recorded on a computer-readable recording medium, and the program recorded on the recording medium may be read into a computer system and executed. Note that the term "computer system" may include hardware such as an OS and peripheral devices.
In addition, the term "computer-readable recording medium" refers to a storage device such as a flexible disk, a magneto-optical disk, a ROM, a writable non-volatile memory such as a flash memory, a portable medium such as a DVD (Digital Versatile Disc), or a hard disk built into a computer system.

Furthermore, the term "computer-readable recording medium" includes devices that retain a program for a certain period of time, such as volatile memory (e.g., DRAM (Dynamic Random Access Memory)) within a computer system that serves as a server or client when a program is transmitted via a network such as the Internet or a communication line such as a telephone line.
The program may be transmitted from a computer system in which the program is stored in a storage device or the like to another computer system via a transmission medium, or by a transmission wave in the transmission medium. Here, the "transmission medium" that transmits the program refers to a medium that has a function of transmitting information, such as a network (communication network) such as the Internet or a communication line (communication line) such as a telephone line.
The program may be a program for implementing some of the above-mentioned functions, or may be a so-called differential file (differential program) that can implement the above-mentioned functions in combination with a program already recorded in the computer system.

1...user terminal, 2...mobile robot, 3...mobile terminal, 4...navigation device, 10...navigation system, 401...operation monitoring unit, 402...operation information storage unit, 403...communication quality acquisition unit, 404...position/communication quality storage unit, 405...map information storage unit, 406...mobile terminal position information storage unit, 407...outdoor population density estimation unit, 408...travel cost calculation unit, 409...order information storage unit, 410...destination acquisition unit, 411...robot information storage unit, 412...operation content storage unit, 413...operator skill information storage unit, 414...operator allocation unit, 415...acceptable quality determination unit, 416...route search unit, 417...route distribution unit, 418...remote operation execution determination unit, 419...remote operation command issuing unit

Claims (9)

A navigation device that provides route information indicating a route from a departure point to a destination to a mobile object that is remotely controlled via a wireless communication line,
a position and communication quality storage unit for storing position and communication quality information in which a position and a communication quality at the position are associated with each other and recorded;
an acceptable quality determination unit that determines an acceptable quality, which is a communication quality that is acceptable in communication related to remote control;
a cost calculation unit that calculates a cost related to movement of the mobile body when communication quality is not taken into consideration for the candidate route, and adds a larger value to the calculated cost when the communication quality does not satisfy the acceptable quality based on the acceptable quality and the position and communication quality information stored in the position and communication quality storage unit, as the difference between the communication quality and the acceptable quality increases, and calculates an overall link cost that is the result of the addition;
a route search unit that searches for the route from among the route candidates based on the calculated total link cost ;
A navigation device comprising: the acceptable quality determination unit determines the acceptable quality for the route candidate based on at least one of road information, outdoor population density, the type of the moving object, and the content of a remote operation for the moving object;
2. The navigation device of claim 1. the acceptable quality determination unit sets the acceptable quality to a higher communication quality as the road width is narrower or the number of people on the road is higher ;
3. A navigation device according to claim 2. The acceptable quality determination unit determines the acceptable quality based on an operation skill level of a remote operator.
A navigation device according to any one of claims 1 to 3. an operator allocation unit that allocates to the moving object a remote operator having an operation skill level different from the operation skill level of the remote operator allocated to the moving object based on a result of the determination of the acceptable quality;
The navigation device of claim 4 further comprising: The communication quality is at least one of throughput, delay, jitter, and packet loss in each of a direction in which the mobile unit transmits data and a direction in which the mobile unit receives data.
A navigation device according to any one of claims 1 to 5. The moving body is a robot that switches between an autonomous mode in which the moving body moves autonomously and a remote control mode in which the moving body moves according to a command received via a wireless communication line,
A navigation device according to any one of claims 1 to 6. A navigation method for providing route information indicating a route from a departure point to a destination to a mobile object remotely controlled via a wireless communication line,
a position and communication quality storage step of storing, in a position and communication quality storage unit, position and communication quality information in which a position and a communication quality at the position are associated with each other and recorded;
an acceptable quality determination step of determining an acceptable quality, which is a communication quality acceptable for communication related to remote control;
a cost calculation step of calculating a cost related to the movement of the mobile body when communication quality is not taken into consideration for the candidate route, and, when the communication quality does not satisfy the acceptable quality based on the acceptable quality and the position and communication quality information stored in the position and communication quality storage unit, adding a larger value to the calculated cost as the difference between the communication quality and the acceptable quality increases, and calculating an overall link cost that is the result of the addition;
a route search step of searching for the route from among the route candidates based on the calculated total link cost ;
Navigation methods including: A computer of a navigation device that provides route information indicating a route from a departure point to a destination to a mobile object that is remotely controlled via a wireless communication line,
a position and communication quality storage step of storing, in a position and communication quality storage unit, position and communication quality information in which a position and a communication quality at the position are associated with each other and recorded;
an acceptable quality determination step of determining an acceptable quality, which is a communication quality acceptable for communication related to remote control;
a cost calculation step of calculating a cost related to the movement of the mobile body when communication quality is not taken into consideration for the candidate route, and, when the communication quality does not satisfy the acceptable quality based on the acceptable quality and the position and communication quality information stored in the position and communication quality storage unit, adding a larger value to the calculated cost as the difference between the communication quality and the acceptable quality increases, and calculating an overall link cost that is the result of the addition;
a route search step of searching for the route from among the route candidates based on the calculated total link cost ;
A computer program for executing the above.

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