Multiple mobile robot systems and methods for controlling the same mobile robots

Abstract

This disclosure provides a mobile robot system comprising: a plurality of mobile robots arranged in a specific space and traveling through the specific space according to their respective travel paths; and a server that periodically receives state values ​​from the plurality of mobile robots and generates and transmits detour routes for densely packed mobile robots among the plurality of mobile robots according to the density of the space based on the state values ​​and a map of the entire space. Upon receiving the detour route, the mobile robot can update its travel path according to the detour route and travel through the specific space. This disclosure enables real-time prevention of collisions between mobile robots when multiple mobile robots are operated to travel in the same specific space. Furthermore, it enables the generation of avoidance routes in real time without requiring further obstacle sensing by the multiple mobile robots. By calculating detour routes with less computation, computation time and costs can also be reduced.

Description

Technical Field

[0001] The present disclosure relates to a robot system in a specific space including a plurality of mobile robots. Specifically, the present disclosure relates to a control method for a mobile robot system that generates and provides a real-time detour route for a mobile robot traveling in a specific space with an individual travel route.

Background Art

[0002] Robots have been developed for industrial use and have been part of factory automation. In recent years, the fields of application of robots have further expanded, and medical robots, aerospace robots, etc. have been developed, and household robots that can be used in ordinary households have also been manufactured. Among these robots, those that can travel independently are called autonomous mobile robots.

[0003] As the use of robots increases, there is a growing demand for robots that can provide various information and services beyond simple repetitive operations.

[0004] As a result, it is possible to perform operations such as moving articles to specific positions or executing operations such as patrols, which are arranged in stores, public facilities, warehouses, ports, factories, etc.

[0005] Generally, the travel routes of autonomous mobile robots are classified into global path planning and local path planning.

[0006] Global path planning means the process of generating a travel route from a starting point to a destination based on a global map before the mobile robot starts traveling.

[0007] Local path planning means the process of updating in real time a travel route for avoiding obstacles existing on the travel route through real-time sensing while following the travel route generated by the global path planning.

[0008] However, when a mobile robot with a travel path based on a full-area map and following a full-area route plan performs real-time sensing within a specific space, the signal processing calculations for the sensing signals from multiple mobile robots traveling within the same space become very numerous, resulting in a significant consumption of time and cost.

[0009] Furthermore, in a system involving multiple mobile robots, it is defined as a system for processing and communicating various events within that space, based on technologies such as cloud computing and CPS (Cyber-Physical System).

[0010] Cloud computing is a service that provides virtualized information and communication technology resources using internet technology.

[0011] Cloud computing allows users to utilize information and communication technology resources (such as servers, storage, networks, and software) as needed.

[0012] When cloud computing allows a cloud server to control a large number of mobile robots, relay servers may be included in each space for control or communication convenience. In this case, only minimal detection signals need to be transmitted for communication convenience and data simplification.

[0013] Korean Patent No. 1679482 discloses a multi-robot system for obstacle avoidance and a method for utilizing a switching formation strategy for obstacle avoidance.

[0014] The obstacle avoidance method for multi-robots includes the steps of: a sensor unit attached to a follower robot confirming the distance between the follower robots, and the control unit of the follower robot determining whether a collision problem has occurred; and the follower robot cooperating with the lead robot to change to an obstacle avoidance formation. However, this only discloses the relationship between the follower robots and cannot respond in real time to collisions between robots that move autonomously according to different paths. [Prior art documents] [Patent Documents]

[0015] [Patent Document 1] Korean Registered Patent No. 10-1679482 (Published November 18, 2016) [Overview of the Initiative] [Problems that the invention aims to solve]

[0016] The first issue addressed by this disclosure is to provide alternative routes that can avoid collisions between mobile robots when operating multiple mobile robots that are moving in real time.

[0017] The second objective of this disclosure is to provide a mobile robot system that can receive real-time location information by generating a whole-area map only, without generating a local map, and can predict the possibility of collisions and provide alternative routes.

[0018] The third issue addressed in this disclosure is to provide a real-time detour route that can prevent collisions by correcting the detour route according to the width of the route on a map of the entire area. [Means for solving the problem]

[0019] The present disclosure provides a mobile robot system including: a plurality of mobile robots disposed in a specific space and traveling in the specific space according to respective traveling routes; and a server that periodically receives state values from the plurality of mobile robots and generates and transmits a detour route for the crowded mobile robots among the plurality of mobile robots according to the density of the space based on the state values and a global map of the space.

[0020] The mobile robot that receives the detour route updates the traveling route according to the detour route and can travel in the specific space.

[0021] The mobile robot system may further include a relay server assigned to each specific space, communicating with the server, and controlling a plurality of mobile robots in the specific space.

[0022] The mobile robot can periodically transmit the current position information and the traveling route information of the mobile robot to the server as the state values.

[0023] The server can combine the current position information for a plurality of mobile robots and extract a pair of mobile robots whose distance between the mobile robots is less than or equal to a threshold as a pair of mobile robots that require a detour route.

[0024] When the distance between the mobile robots is less than or equal to a threshold and less than or equal to the topological node interval of the global map, the server can generate a very detoured route, and when it is greater than the topological node interval of the global map, the server can generate a normal detour route.

[0025] The server sets a section that overlaps on the reverse vector among the traveling routes of the extracted pair of mobile robots as an initial overlapping section, sets a section where the movement of the pair of mobile robots overlaps in time among the initial overlapping sections as a time-overlapping section, and can generate the normal detour route for the time-overlapping section.

[0026] The server can generate two normal detour routes for the pair of mobile robots to shift both ends of the time overlapping interval in the same direction and detour.

[0027] When the server generates the emergency detour route, on the travel route of the dense pair of mobile robots, a section that overlaps on the reverse vector from the current position to the destination is set as the overlapping section, a virtual node is set within the overlapping section, and the emergency detour route can be generated based on the virtual node.

[0028] When there is a narrow path within the overlapping section on the global map of the specific space, the server can generate a normal detour route or an emergency detour route excluding the narrow path.

[0029] When the normal detour route or the emergency detour route with the narrow path is transmitted to the mobile robot, other mobile robots can maintain the standby mode outside the narrow path so that the mobile robot that first enters the narrow path passes through the narrow path first.

[0030] On the other hand, in a method for controlling a mobile robot that is arranged in a specific space and controls a plurality of mobile robots that travel through the specific space according to their respective travel routes, a stage in which state values are periodically transmitted from the plurality of mobile robots; a stage of calculating the density of the space based on the state values and the global map of the space, and extracting a dense pair of mobile robots from the plurality of mobile robots; and a stage of generating a detour route for the extracted pair of mobile robots and transmitting it to the pair of mobile robots; A method for controlling a mobile robot is provided.

[0031] The method may further include a stage in which the mobile robot receives the detour route, updates the travel route to the detour route, and continues to travel through the specific space.

[0032] In the stage where the state value is transmitted, the current position information and the travel route information of the mobile robot can be periodically received from the mobile robot as the state value.

[0033] The step of extracting densely packed pairs of mobile robots may include the steps of: extracting current position information for the plurality of mobile robots; and calculating the current position information relative to each other and extracting pairs of mobile robots where the distance between the mobile robots is less than or equal to a threshold as the densely packed pairs of mobile robots.

[0034] In the step of generating the detour route, if the distance between the mobile robots is below a threshold and below the topology node interval of the overall map, an emergency detour route can be generated, and if it is greater than the topology node interval of the overall map, a normal detour route can be generated.

[0035] The process may include the steps of setting an initial overlapping section as the section of the travel path of the densely packed mobile robot pair that overlaps in the opposite vector, setting a section of the initial overlapping section in which the movement of the mobile robot pair overlaps in time as a time-overlapping section, and generating the normal detour path for the time-overlapping section.

[0036] For a densely packed pair of mobile robots, two normal detour routes can be generated that bypass the time-overlapping section by shifting both ends in the same direction.

[0037] When generating the emergency detour route, on the travel paths of the densely packed mobile robot pair, overlapping sections on the inverse vector from the current position to the destination can be set as overlapping sections, virtual nodes can be set within the overlapping sections, and the emergency detour route can be generated based on the virtual nodes.

[0038] If a narrow road exists within the overlapping section on the overall map of the specified space, a normal detour route or an emergency detour route can be generated that excludes the narrow road. [Effects of the Invention]

[0039] The aforementioned solution enables the prevention of collisions between mobile robots in real time when multiple mobile robots are operated to travel within the same specific space.

[0040] Furthermore, avoidance routes can be generated in real time without requiring additional obstacle sensing by multiple mobile robots. By generating detour routes with less computation, computation time, and costs can be reduced.

[0041] Furthermore, by diverting vehicles sequentially through narrow roads instead of selecting detours, depending on the regional characteristics of the current routes, the possibility of collisions can be further reduced. [Brief explanation of the drawing]

[0042] [Figure 1] This is a schematic diagram illustrating a plurality of mobile robot systems according to one embodiment of the present disclosure. [Figure 2] Figure 1 is a detailed view of an individual mobile robot system. [Figure 3] Figure 2 is a configuration diagram illustrating one application example of a cloud server. [Figure 4] This is an operation diagram of the occupancy detection unit of a cloud server according to one embodiment of the present disclosure. [Figure 5] This is a schematic diagram showing the distances between multiple mobile robots within a mobile robot system. [Figure 6] This is an operation diagram of the bypass route generation unit of a cloud server according to one embodiment of the present disclosure. [Figure 7a] This is a schematic diagram illustrating the operation shown in Figure 6. [Figure 7b] This is a schematic diagram illustrating the operation shown in Figure 6. [Figure 8] This is an operation diagram of the emergency bypass route generation unit of a cloud server according to one embodiment of the present disclosure. [Figure 9a] This is a schematic diagram to explain the operation diagram in Figure 8. [Figure 9b] This is a schematic diagram to explain the operation diagram in Figure 8. [Figure 10] This is a diagram illustrating the process of generating detour routes when narrow roads exist on the overall map. [Figure 11] This is a schematic diagram illustrating the operation shown in Figure 10. [Figure 12a] Figure 11 shows a simulation of the robot's movements. [Figure 12b] Figure 11 shows a simulation of the robot's movements. [Modes for carrying out the invention]

[0043] The use of terms such as "first," "second," etc., preceding the components mentioned below is intended to avoid confusion of the components being referred to, and is unrelated to the order, importance, or hierarchical relationship between the components. For example, an invention that includes only the second component and does not have the first component is also feasible.

[0044] The thickness and size of each component in the drawings are exaggerated, omitted, or approximate for the sake of clarity and ease of explanation. Furthermore, the size and area of ​​each component do not fully reflect their actual size or area.

[0045] Furthermore, angles and directions mentioned in the process of describing the structure of this disclosure shall be based on those shown in the drawings. If the reference point and positional relationship of angles are not clearly mentioned in the description of the structure in the specification, refer to the relevant drawings.

[0046] Figure 1 is a schematic diagram illustrating a plurality of mobile robot systems according to one embodiment of the present disclosure, and Figure 2 is a detailed diagram of an individual mobile robot system in Figure 1.

[0047] Referring to Figure 1, a plurality of mobile robot systems according to one embodiment of the present disclosure may include a cloud server 10, a plurality of relay servers 20, and a plurality of mobile robots 30.

[0048] The cloud-based robot system provides integrated management and control for multiple robots 30 that are dispersed across multiple spaces, separated from each other.

[0049] In this configuration, each space is functionally or geographically separated, and each space is provided with its own relay server 20 for controlling multiple robots 30 located within it.

[0050] Although identical robots 30 are placed in each space, alternatively, different types of robots 30 may also be placed within the same space.

[0051] For example, space 1 (A1) is equipped with a relay server 20, and multiple delivery robots and multiple monitoring robots 30 (R1, R2, R3, R4) are positioned within it.

[0052] Different or identical robots 30 located in each space can communicate with the relay server 20 or cloud server 10 located in that space to provide their assigned services.

[0053] Preferably, the cloud robot system according to one embodiment of the present disclosure includes a plurality of mobile robots 30 and their respective relay servers 20 provided in each space, and a cloud server 10 that transmits and receives information between each relay server 20 and the mobile robots 30, generates travel paths (P1, P2, P3, P4) for each mobile robot 30 based on global map information of the space in which each mobile robot 30 moves, provides them to each mobile robot 30, corrects and updates them in real time, and provides them to the mobile robots 30.

[0054] The relay server 20 monitors the status of multiple robots 30 within its assigned space at close range, periodically receives status values ​​from each of the multiple mobile robots 30, and transmits them to the cloud server 10.

[0055] Furthermore, by transmitting the corrected travel path information received from the cloud server 10 to each mobile robot 30, the mobile robots 30 can be controlled to change to the corrected travel path in real time.

[0056] Multiple mobile robots 30, relay servers 20, and cloud servers 10 are equipped with communication means (not shown) that support one or more communication standards, and can communicate with each other.

[0057] For example, multiple mobile robots 30, a relay server 20, and a cloud server 10 can communicate wirelessly using wireless communication technologies such as IEEE 802.11 WLAN, IEEE 802.15 WPAN, UWB, Wi-Fi, Zigbee, Z-wave, and Bluetooth. The mobile robots 30 can use different communication methods depending on the communication methods of other devices they communicate with or the cloud server 10 and relay server 20.

[0058] In particular, multiple mobile robots 30 can communicate wirelessly with other robots 30 and / or relay servers 20 and cloud servers 10 via a 5G network. When mobile robots 30 communicate wirelessly via a 5G network, an ultra-low latency / high-capacity data transmission network can be realized.

[0059] More specifically, 5G networks are communication technologies that provide transmission speeds of tens of Gbps in the wireless section, enabling ultra-low latency, large capacity, and ultra-real-time data transmission at speeds exceeding Gbps and ultra-low latency in milliseconds using multiple modules according to the quality requirements of each service. Such 5G networks can provide network quality equivalent to high-speed wired networks while simultaneously offering the advantages of wireless communication.

[0060] Such a 5G network can be controlled in a cloud-based robot system to provide services optimized for each mobile robot 30 and each space between the robot 30 and the relay server 20, between the relay server 20 and the cloud server 10, and between the robot 30 and the cloud server 10.

[0061] Furthermore, multiple mobile robots 30 and relay servers 20 can communicate using MQTT (Message Queueing Telemetry Transport), and can also communicate using HTTP (HyperText Transfer Protocol), but are not limited to these methods.

[0062] In some cases, it is possible to support two or more communication standards between multiple robots 30, relay servers 20, and cloud servers 10, and to use the optimal communication standard depending on the type of communication data and the type of equipment participating in the communication.

[0063] In this specification, "user" refers to a person who provides or utilizes services through multiple robots 30, and may include individual customers who purchase or rent robots 30 for use in their offices, etc., as well as managers and employees of companies that use robots 30 to provide services to their employees or customers, and customers who use services provided by such companies. Therefore, "user" can include both individual customers (Business to Consumer: B2C) and corporate customers (Business to Business: B2B).

[0064] The cloud server 10 stores area-wide map information for each of the physically dispersed robots 30, generates travel routes based on the area-wide map information for each area and the duties assigned to each mobile robot 30, and provides them to each mobile robot 30 via the relay server 20. In addition, it corrects the stored travel routes in real time according to the status values ​​of the mobile robots 30, generates detour routes, and provides them to the mobile robots 30 via the relay server 20.

[0065] The cloud server 10 generates a path generation model or engine for the mobile robots 30 in each space. The base model or base engine may include a general-purpose model or general-purpose engine that can be applied to similar mobile robots 30 depending on the environment of the mobile robot system.

[0066] The cloud server 10 receives environmental information about each local environment, i.e., each space where multiple mobile robots 30 are located, i.e., global map information, and receives the number of each mobile robot and their job tables. Based on this comprehensive assessment, it can perform deep learning to upgrade the base model to be optimized for that environment.

[0067] As shown in Figure 2, the relay server 20 is provided in each space and can transmit and receive data with multiple different or identical robots 30 located in that space, and can transmit and receive data with the cloud server 10 to control each robot 30.

[0068] The relay server 20 deviates from the conventional method of processing data on the cloud server 10 and uses technology to process data at the edge where the data is generated. Real-time data is processed on the relay server 20, and secondary processing is performed as needed by communicating with the central cloud.

[0069] As shown in Figure 2, each relay server 20 is located in a separate virtual space or a physically separated space, and controls multiple robots 30 that are located in that space and provide services.

[0070] For example, as shown in Figure 2, the relay server 20 can control multiple robots 30 (R1~R4) that provide goods movement services within a logistics warehouse, and these robots 30 include transport robots, monitoring robots, etc.

[0071] In this way, the multiple mobile robots 30 positioned in the space are subordinate to the relay server 20, and when they start operating while sending and receiving data with the relay server 20 and the cloud server 10, they individually travel according to the transmitted travel paths (P1 to P4) and perform their assigned duties.

[0072] Figure 3 is a configuration diagram illustrating one application example of the cloud server 10 shown in Figure 2.

[0073] Referring to Figure 3, the cloud server 10 may include a communication unit 11, a storage unit 13, a traffic congestion detection unit 15, a detour route generation unit 17, and an emergency detour route generation unit 19.

[0074] Specifically, in the case of a cloud server 10, the memory unit 13 can store algorithms for generating travel routes and detour routes for each robot based on whole-area map information for each space, and can store and manage data acquired from multiple identical or mobile robots 30 within each space based on IoT technology.

[0075] These memory units 13 may be various storage devices such as ROM, RAM, EPROM, flash drives, and hard drives, or they may be web storage that performs the memory functions of the memory units 13 over the internet.

[0076] Furthermore, in some embodiments, the software components stored in the memory unit 13 may include an operating system, a communication module (or set of commands), a contact / motion module (or set of commands), a graphics module (or set of commands), a text input module (or set of commands), a GPS module (or set of commands), and an application (or set of commands).

[0077] As described above, the communication unit 11 of the cloud server 10 can perform various communications depending on the communication method required by the environment. In particular, it can use the 5G network to perform communications between the robot 30 and the relay server 20, between the relay server 20 and the cloud server 10, and between the robot 30 and the cloud server 10.

[0078] The cloud server 10 individually generates travel paths (P1 to P4) for each mobile robot 30 based on a global map. Here, the global map is a map of the work environment used by the mobile robot 30, and information about static obstacles, which are areas where the mobile robot 30 cannot move, is predefined. The travel paths generated by the cloud server 10 are called initial travel paths (P1 to P4).

[0079] For example, referring to Figure 2, the cloud server 10 takes into account static obstacles defined on the overall map and assigns each mobile robot 30 (R1 to R4) a travel path (P1 to P4) in each space for a predetermined amount of time.

[0080] According to one embodiment of this disclosure, the cloud server 10 can generate initial travel paths (P1 to P4) using algorithms such as the A* algorithm (A star algorithm) or the RRT (Rapidly exploring random tree) algorithm.

[0081] The congestion detection unit 15 of the cloud server 10 periodically receives status information of each robot 30 (R1 to R4) from the communication unit 11, grasps the current location and travel path of the mobile robots 30 (R1 to R4) in operation, and determines the distance between multiple mobile robots 30 (R1 to R4) in the same space.

[0082] The traffic congestion detection unit 15 periodically receives information on the current location of the mobile robot 30 from each relay server 20, calculates the distance between multiple mobile robots 30 (R1 to R4) at regular intervals, and determines that there is a possibility of traffic congestion if the distance is below a threshold.

[0083] If there is a possibility of congestion, the congestion detection unit 15 transmits information about the mobile robot pair to the detour route generation unit 17.

[0084] The detour route generation unit 17 receives a list of robot pairs below a threshold from the congestion detection unit 15 and generates a detour route for each mobile robot pair.

[0085] The aforementioned detour route is generated from the overall map information and can be generated by comparing and processing only the overall map information and the initial travel route (P1-P4) without receiving real-time sensing information from the mobile robot 30 (R1-R4) or generating a local map.

[0086] On the other hand, if the distance between each of the multiple mobile robots 30 (R1 to R4) calculated by the congestion detection unit 15 is smaller than the interval between topology nodes, the emergency detour route generation unit 19 generates an emergency detour route.

[0087] The emergency detour route generation unit 19 receives information about the robot(R) pair, generates an emergency detour route, and provides it to the mobile robots 30 (R1 to R4) via the communication unit 11.

[0088] In this manner, the cloud server 10 periodically receives real-time status values ​​of each mobile robot 30 (R1 to R4), namely their current location and travel route information, through the relay server 20. It then compares these values ​​to predict the possibility of congestion and generates and provides alternative routes accordingly.

[0089] In this case, the cloud server 10 can generate different types of detour routes on the overall map depending on whether the area is a wide road or a narrow road.

[0090] The operation of each of the 10 cloud server's functional modules will be explained individually below.

[0091] Figure 4 is an operation diagram of the congestion detection unit 15 of a cloud server 10 according to one embodiment of the present disclosure, and Figure 5 is a schematic diagram showing the distance between multiple mobile robots 30 (R1 to R4) in a mobile robot (R) system.

[0092] Referring to Figure 4, multiple mobile robots (R1, R2) moving within a single space include information about travel paths (P1, P2) set based on a full-area map of that space, and travel within that space according to the said travel paths (P1, P2).

[0093] These mobile robots (R1, R2) periodically transmit status values, i.e., current location information and stored travel path information (P1, P2) of the mobile robots (R1, R2) to the cloud server via the relay server 20 (S10).

[0094] The congestion detection unit 15 of the cloud server 10 periodically receives status values ​​of the mobile robots (R1, R2) and, based on the current positions of multiple mobile robots (R1, R2) in a single space, determines whether or not a robot pair exists in a high-density space where the distance between multiple mobile robots (R1, R2) is below a threshold.

[0095] Specifically, as shown in Figure 5, when the current position information of the mobile robots (R1, R2) for the current cycle is received, the distance (d1) between the first robot (R) and the second robot (R) is calculated as shown in Equation 1.

[0096]

number

[0097] The traffic congestion detection unit 15 extracts pairs of mobile robots (R1, R2) where the d1 value between the current positions of multiple mobile robots (R1, R2) received in the current cycle is smaller than a threshold value (S11).

[0098] In this case, if the value of d1 is less than or equal to the threshold, and the value of d1 is smaller than the TP, which is the topology node interval on the overall map, then information about the robot (R) pair is transmitted to the emergency detour route generation unit 19.

[0099] If the value of d1 is greater than the topology node interval and less than or equal to a threshold, it is determined that there is a possibility of general congestion, and information regarding the robot pair is transmitted to the detour route generation unit 17 (S12).

[0100] On the other hand, Figure 6 is an operation diagram of the bypass route generation unit 17 of the cloud server 10 according to one embodiment of the present disclosure, and Figures 7a and 7b are schematic diagrams for explaining the operation diagram of Figure 6.

[0101] Referring to Figures 6, 7a, and 7b, the detour route generation unit 17 receives a real-time list of robot pairs below a threshold distance from the congestion detection unit 15, and also receives information about the mobile robots.

[0102] From the extracted robot pairs, the current position information and travel path information of each mobile robot (R1, R2) are extracted and verified (S100).

[0103] In the aforementioned pair of robots, the travel paths are compared to determine whether or not there is an overlapping section on the inverse vector (S110).

[0104] In other words, the first robot (R1) and the second robot (R2) are identified as a robot pair with a risk of congestion, and it is determined whether there is an overlapping section in the travel paths of these robots (R1, R2) in opposite vector directions. This is called the initial overlapping section.

[0105] Next, as shown in Figure 7a, the movement speed is calculated based on the current positions of both robots (R1 and R2) for the overlapping section, and it is determined whether or not an overlapping section (OP) exists in terms of time (S120).

[0106] The aforementioned time overlap interval (OP) is smaller than or equal to the initial overlap interval, and if the time overlap interval (OP) exists, the time overlap interval (OP) is represented by topology nodes (n1 to n7) as shown in Figure 7a.

[0107] For example, in Figure 7a, the time overlap interval (OP) could be the interval between the first node (n1) and the seventh node (n7) between the first robot (R1) and the second robot (R2).

[0108] Next, the detour route generation unit 17 generates detour routes for the first robot (R1) and the second robot (R2) from their current positions to the time-overlapping section (OP) (S130).

[0109] In this case, for each robot (R1, R2), a detour path can be generated so as to shift the time-overlapping section (OP) from the front of the time-overlapping section (OP) in a first direction.

[0110] For example, the first robot (R1) and the second robot (R2) can similarly generate detour paths that shift to the right relative to the front.

[0111] In other words, the first robot (R1) can generate a detour path that detours to the right from the first node (n1), passes through the first detour point (c2) to the fifth detour point (c6), and then returns to the seventh node (n7).

[0112] On the other hand, the second robot (R2) can generate a detour path that detours to the right from the seventh node (n7), passes through the sixth detour point (c2') to the tenth detour point (c6'), and returns to the first node (n1).

[0113] Once such detour paths are generated for each robot (R1, R2), the first robot (R1) and the second robot (R2) are provided with paths that allow them to traverse the time-overlapping interval (OP) without colliding with each other.

[0114] The detour route generation unit 17 transmits the generated detour route information for each robot (R1, R2) to the relay server 20 via the communication unit 11, and the information is then transmitted to the robots (R1, R2) via the relay server 20 (S140).

[0115] The mobile robots (R1, R2) can change their routes in real time according to the transmitted detour route and prepare for collisions.

[0116] On the other hand, Figure 8 is an operation diagram of the emergency detour route generation unit 19 of a cloud server according to one embodiment of the present disclosure, and Figures 9a and 9b are schematic diagrams for explaining the operation diagram of Figure 8.

[0117] Referring to Figures 8 and 9a and 9b, the emergency detour route generation unit 19 receives a robot pair list from the congestion detection unit 15 in which the real-time distance between robots 30 is below a threshold and the real-time distance between robots 30 is below the topology node (TP) interval, and also receives information on the mobile robot (R) (S200).

[0118] From the extracted robot pairs, the current location information and travel path information of each mobile robot (R1, R2) are extracted.

[0119] At this time, the travel paths of each mobile robot (R1, R2) in the robot pair are compared with each other to check whether there is a possibility of collision.

[0120] Specifically, as shown in Figure 9a, the vectors from the current location to the destination of each robot (R1, R2) are checked (S210), and if the vectors of both robots (R1, R2) form opposite vectors and have an overlapping section (OP), it is determined that there is a possibility of collision (S220).

[0121] In other words, when the distance between the first robot (R1) and the second robot (R2) becomes very close and an overlapping interval (OP) is searched where the vectors of both robots (R1, R2) are in opposite vector directions, a virtual node is set up within the said overlapping interval (OP) (S230).

[0122] Since the overlapping interval (OP) is smaller than the topology node (TP) interval, it cannot represent a topology node. Therefore, virtual nodes (i1~i5) with intervals smaller than the topology node interval are set up as shown in Figure 9b.

[0123] For example, as shown in Figure 9b, the overlapping interval (OP) in which virtual nodes are configured may be the interval between the first robot (R1) and the second robot (R2), and between the first node (n1) and the second node (n2).

[0124] Next, the emergency detour route generation unit 19 generates emergency detour routes for the overlapping section (OP) for the first robot (R1) and the second robot (R2) (S240).

[0125] At this time, an emergency detour path is provided for each robot (R1, R2) to shift the overlapping section (OP) in the first direction.

[0126] For example, the first robot (R1) and the second robot (R2) can similarly generate emergency detour paths that shift to the right relative to the front.

[0127] In other words, the first robot (R1) can generate an emergency detour path that detours to the right from the first node (n1), passes through the first detour point (i1') to the fifth detour point (i5'), and returns to the second node (n2).

[0128] On the other hand, the second robot (R2) can generate an emergency detour route that detours to the right from the second node (n2), passes through the sixth detour point (i1'') to the tenth detour point (i5''), and returns to the first node (n1).

[0129] In this way, when emergency detour routes are generated for each robot (R1, R2), the first robot (R1) and the second robot (R2) are provided with paths that allow them to traverse the overlapping section (OP) without colliding with each other.

[0130] The emergency detour route generation unit 19 transmits the emergency detour route information generated for each robot (R1, R2) to the relay server 20 via the communication unit 11, and then transmits it to the robots (R1, R2) via the relay server 20 (S250).

[0131] The mobile robots (R1, R2) can change their routes in real time according to the transmitted emergency detour route and prepare for collisions.

[0132] In this way, by receiving real-time current position information of multiple mobile robots 30 within a single space, continuously calculating the relative distance based on this information, and updating avoidance paths between nearby robots 30, multiple mobile robots 30 traveling within the same space can move without colliding with each other.

[0133] Furthermore, the number of mobile robots 30 can significantly reduce the amount of computation required by correcting their initially set travel paths based on a map of the entire area to avoid collisions, without performing real-time obstacle detection.

[0134] On the other hand, the detour route generation unit 17 and the emergency detour route generation unit 19 can correct the detour route according to the stored map of the entire area.

[0135] The following describes the process of generating corrected detour routes based on a map of the entire area.

[0136] Figure 10 is a diagram illustrating the generation of detour routes when narrow roads exist on the overall map, Figure 11 is a schematic diagram illustrating the operation diagram in Figure 10, and Figures 12a and 12b show a simulation of the operation of the robot (R) related to Figure 11.

[0137] The detour route generation unit 17 and the emergency detour route generation unit 19 of the cloud server 10 distinguish between information on wide roads and narrow roads within the overall map information (S300).

[0138] In this case, a wide path is defined as a path with a width that allows two mobile robots 30 to travel simultaneously, and a narrow path is defined as a path with a width that allows one mobile robot 30 to travel, but does not allow two mobile robots 30 to travel simultaneously.

[0139] In this way, with the entire area map information for each space distinguished into wide roads and narrow roads along the route, the detour route generation unit 17 and the emergency detour route generation unit 19 generate detour routes and emergency detour routes, respectively, for the extracted robot pairs.

[0140] At this point, it is determined whether the overlapping section matches a narrow road in the overall map information (S310).

[0141] In other words, if at least a portion of the overlapping section (OP) coincides with a narrow road (S320), the effectiveness of the detour route that bypasses the narrow road is judged to be low, and the detour route is corrected (S330).

[0142] Specifically, if an overlapping section (OP) and a narrow road partially coincide, the overlapping section is excluded to form a detour route.

[0143] For example, as shown in Figure 11, if the overlapping section (OP) of the first robot (R1) and the second robot (R2) lies between the first node (n1) and the seventh node (n7), it can be determined that the section between the third node (n3) and the fourth node (n4) within the overlapping section (OP) coincides with a narrow road (NR). In this way, if a portion of the overlapping section (OP) is determined to be a narrow road (NR), the third node (n3) and the fourth node (n4) are excluded, and the detour route is corrected to bypass the section between the first node (n1) and the third node (n3), and the section between the fourth node (n4) and the seventh node (n7).

[0144] The corrected detour path generated in this way leads the first robot (R1) from the first node (n1) to the third node (n3) via the second detour point (c2), then through the narrow path (NR), back to the fourth node (n4), and finally to the seventh node (n7) via the fifth detour point (c5) and the sixth detour point (c6).

[0145] Such corrected detour routes can also generate detour points that are shifted in a certain direction, for example to the right, with the overlapping section (OP) facing forward.

[0146] On the other hand, the corrected detour path of the second robot (R2), which enters the overlapping section (OP) from the opposite vector direction, goes from the seventh node (n7) to the fourth node (n4) via the seventh detour point (c2') and the eighth detour point (c3'), then passes through the narrow path (NR), and from the third node (n3) follows the detour path again, passing through the ninth detour point (c6') to the first node (n1).

[0147] At this time, the corrected detour route is transmitted to the first robot (R1) and the second robot (R2), which have a high probability of collision, and the first robot (R1) and the second robot (R2) update their set travel routes according to the corrected detour route and travel according to the corrected detour route (S340).

[0148] In this case, when the first robot (R1) and the second robot (R2) reach the narrow passage (NR), they can be configured to pass through the narrow passage (NR) first, relative to the robot (R1) that enters the third node (n3) and the fourth node (n4) first.

[0149] The order in which the narrow path (NR) is passed can be transmitted together with the corrected detour route, but is not limited to this.

[0150] The order in which the robots (R1, R2) pass through the narrow passage (NR) can be calculated based on their current position, the distance to the narrow passage (NR), and their current speed. It can be assumed that the robots (R1, R2) will continue to travel at the same speed as their current speed.

[0151] As shown in Figure 12a, the first robot (R1) and the second robot (R2) traveling in the overlapping section travel according to the corrected detour path, and when they encounter a narrow road (NR), the second robot (R2) remains stationary and waits until the first robot (R1), which entered the narrow road (NR) first, has passed through the narrow road (NR).

[0152] As shown in Figure 12b, after the first robot (R1) has completely passed through the narrow passage (NR), the second robot (R2) enters the narrow passage (NR) and travels along the corrected detour path. Therefore, the corrected detour paths of both robots (R1 and R2) are temporally separated in the narrow passage (NR), and although the robots travel along their respective corrected paths afterward, they do not travel over the temporally corresponding nodes.

[0153] However, even without this temporal response, the system will not affect subsequent travel because a new route search will be performed by transmitting status values ​​related to the current location again in the next cycle.

[0154] On the other hand, if there are no narrow paths (NR) in the overlapping section (OP) (S350), the detour route generation unit 17 and the emergency detour route generation unit 19 of the cloud server 10 generate a detour route and an emergency detour route, respectively, according to the flowcharts in Figures 6 and 8, and transmit the detour route to the robot 30 via the relay server (S360).

[0155] In this way, the cloud server 10 can receive full-area map information for each space and real-time status information of multiple mobile robots 30 in each space, and correct and provide travel routes based on the full-area map information.

[0156] Since this type of route correction is achieved using only the overall map information without generating a local map, it does not require the robot 30 to detect obstacles, and the cost of expensive obstacle sensors such as LiDAR and the processing costs of sensor values ​​can be significantly reduced.

[0157] Furthermore, the calculation can be greatly simplified by calculating the collision risk based on the relative distance between multiple robots 30, using the initially set travel path from the entire area map, and then calculating a detour route.

[0158] The robot system relating to this disclosure is not limited to the configuration and methods of the embodiments described above, and can be configured by selectively combining all or part of each embodiment, so that various modifications can be made to the embodiments.

[0159] Furthermore, the control method for the robot system according to the embodiment of this disclosure can be implemented as processor-readable code on a processor-readable recording medium. A processor-readable recording medium includes all types of recording devices on which processor-readable data is recorded. Examples of processor-readable recording media include ROM, RAM, CD-ROM, magnetic tape, floppy disks, optical data recording devices, and also those implemented in the form of carrier waves, such as transmission over the Internet. Moreover, processor-readable recording media can be distributed across networked computer systems, and processor-readable code can be recorded and executed in a distributed manner.

[0160] Furthermore, while preferred embodiments of the present disclosure have been shown and described above, the present disclosure is not limited to the specific embodiments described above, and various modifications can be carried out by a person with ordinary skill in the art to which the invention pertains, without deviating from the gist of the present disclosure claimed in the claims, and such modifications should not be individually understood from the technical idea or prospects of the present disclosure. [Explanation of Symbols]

[0161] 10: Cloud Server 20: Relay Server 30: Mobile robots

Claims

1. Multiple mobile robots arranged in a specific space and traveling through the specific space according to their respective travel paths; and A server that periodically receives status values ​​from the plurality of mobile robots and generates and transmits detour routes for densely packed mobile robots among the plurality of mobile robots based on the status values ​​and a map of the entire space, according to the density of the space; A mobile robot system including...

2. The mobile robot system according to claim 1, wherein the mobile robot, upon receiving the detour route, updates its travel route according to the detour route and travels through the specific space.

3. The mobile robot system according to claim 2, further comprising a relay server assigned to each of the aforementioned specific spaces, which transmits and receives data with the server and controls a plurality of mobile robots in the aforementioned specific spaces.

4. The mobile robot system according to claim 1, wherein the mobile robot periodically transmits the current location information and the travel path information of the mobile robot to the server as state values.

5. The mobile robot system according to claim 4, wherein the server combines current position information of multiple mobile robots and extracts pairs of mobile robots where the distance between them is less than or equal to a threshold as pairs of mobile robots that require a detour route.

6. The mobile robot system according to claim 5, wherein the server generates an emergency detour route when the distance between the mobile robots is less than or equal to a threshold and less than or equal to the topology node interval of the overall map, and generates a normal detour route when it is greater than the topology node interval of the overall map.

7. The mobile robot system according to claim 6, wherein the server sets the section of the extracted travel path of the mobile robot pair that overlaps on the inverse vector as an initial overlap section, sets the section of the initial overlap section in which the movement of the mobile robot pair overlaps in time as a time overlap section, and generates the normal detour path for the time overlap section.

8. The mobile robot system according to claim 7, wherein the server generates two normal detour paths for the mobile robot pair, which detour by shifting both ends of the time-overlapping section in the same direction.

9. The mobile robot system according to claim 8, wherein when the server generates the emergency detour route, it sets overlapping sections on the travel paths of the densely packed mobile robot pair as overlapping sections on the inverse vector from the current position to the destination, sets a virtual node within the overlapping section, and generates the emergency detour route based on the virtual node.

10. The mobile robot system according to claim 8 or 9, wherein the server generates a normal detour route or an emergency detour route that excludes the narrow road if the narrow road exists within the overlapping section on the map of the entire area of ​​the specific space.

11. The mobile robot system according to claim 10, in which, when the normal detour route or emergency detour route in which the narrow path exists is transmitted to the mobile robot, other mobile robots maintain a standby mode outside the narrow path so that the mobile robot that entered the narrow path first passes through the narrow path first.

12. A method for controlling multiple mobile robots that are arranged in a specific space and travel through the specific space according to their respective travel paths, A step in which state values ​​are periodically transmitted from the aforementioned multiple mobile robots; A step of calculating the density of the space based on the state value and the overall map of the space, and extracting densely packed pairs of mobile robots from among the plurality of mobile robots; and A step of generating a detour route for the extracted mobile robot pair and transmitting it to the mobile robot pair; A method for controlling a mobile robot, including the control of a mobile robot.

13. The method for controlling a mobile robot according to claim 12, further comprising the step of the mobile robot receiving the detour route, updating the travel route to the detour route, and continuing to travel through the specific space.

14. The stage in which the aforementioned state value is transmitted is: The method for controlling a mobile robot according to claim 13, wherein the current location information and the travel path information of the mobile robot are periodically received from the mobile robot as state values.

15. The step of extracting the densely packed mobile robot pairs is the step of extracting current position information for the plurality of mobile robots; and A step of calculating the current position information between the mobile robots and extracting the mobile robot pairs in which the distance between the mobile robots is less than or equal to a threshold as the densely packed mobile robot pairs; A method for controlling a mobile robot according to claim 14, including the following:

16. The step of generating the aforementioned detour route is: A method for controlling a mobile robot according to claim 15, wherein an emergency detour route is generated when the distance between the mobile robots is less than or equal to a threshold and less than or equal to the topology node interval of the overall map, and a normal detour route is generated when it is greater than the topology node interval of the overall map.

17. In the step of setting the section of the travel path of the densely packed mobile robot pair that overlaps on the opposite vector as the initial overlap section, The steps include setting the interval in the initial overlapping interval in which the movement of the mobile robot pair overlaps in time as the time overlapping interval, and A method for controlling a mobile robot according to claim 16, further comprising the step of generating the normal detour route for the time overlap section.

18. A method for controlling a mobile robot according to claim 17, which generates two normal detour paths for a densely packed pair of mobile robots, by shifting both ends of the time-overlapping section in the same direction to bypass it.

19. The method for controlling a mobile robot according to claim 18, wherein when generating the emergency detour route, a section overlapping on the inverse vector from the current position to the destination on the travel path of the densely packed mobile robot pair is set as an overlapping section, a virtual node is set within the overlapping section, and the emergency detour route is generated based on the virtual node.

20. A method for controlling a mobile robot according to claim 18 or 19, which generates a normal detour route or an emergency detour route that excludes a narrow road when a narrow road exists within the overlapping section on a map of the entire area of ​​the specified space.

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