Ultra-wideband-based method and system of mobile robot to travel between floors using elevator for autonomous driving in multi-story building

Abstract

The present invention relates to an ultra-wideband-based method of a mobile robot to travel between floors using an elevator for autonomous driving in a multi-story building. The present method may include the steps in which: a mobile robot boards an elevator on the basis of an ultra-wideband signal; the mobile robot having boarded the elevator recognizes a floor of the moving elevator; and when the recognized floor corresponds to a target floor of the mobile robot, the mobile robot alights from the elevator.

Description

Method and system for elevator interfloor movement of a mobile robot for autonomous driving in a multi-story building based on ultra-wideband

[0001] The present invention relates to an elevator floor-to-floor movement method and system for autonomous driving of a mobile robot in a multi-story building based on an ultra-wideband, and more particularly, to an elevator floor-to-floor movement method and system for autonomous driving of a mobile robot in a multi-story building based on an ultra-wideband, which enables the mobile robot to recognize the elevator floor through an ultra-wideband (UWB) frequency installed at both ends of each floor of the elevator, and shorten the initial position (localization) time by estimating the position through the ultra-wideband frequency when getting off the elevator.

[0002]

[0003] Wheelchairs are used as assistive devices to support the mobility of those who have difficulty walking normally due to congenital or acquired reasons. Due to the continuous aging of the population, the number of electric wheelchair owners reached 90,037 in 2020, a 42% increase from the previous survey of 63,015 in 2017. Among users of electric assistive devices, 35.5% have experienced an accident, and those with upper limb disabilities who have difficulty controlling electric wheelchairs account for 21.7% of the disabled population. Therefore, care service personnel are needed to assist with the mobility of these individuals, but this is in short supply due to the aging population. Therefore, an autonomous driving system is needed to assist those who have difficulty operating electric wheelchairs.

[0004]

[0005] The present invention was created to solve the aforementioned problems, and its purpose is to provide a method and system for moving an elevator between floors of a mobile robot for autonomous driving in a multi-story building based on ultra-wideband.

[0006] The purposes of the present invention are not limited to those mentioned above, and other purposes not mentioned will be clearly understood from the description below.

[0007]

[0008] To achieve the above objectives, a method for moving between elevator floors of a mobile robot for autonomous driving in a multi-story building based on ultra-wideband signals is disclosed according to one embodiment of the present invention. The method may include a step of the mobile robot boarding an elevator based on an ultra-wideband signal, a step of the mobile robot boarding the elevator recognizing the floor of the moving elevator, and a step of the mobile robot disembarking if the recognized floor is the target floor of the mobile robot.

[0009] In addition, according to one embodiment of the present invention, the step of boarding an elevator may include a step of the mobile robot collecting ultra-wideband frequency data transmitted from an ultra-wideband device attached to the elevator through an ultra-wideband sensor, a step of the mobile robot analyzing the collected ultra-wideband frequency data, a step of estimating an angle and a position of the mobile robot based on the analyzed result, and a step of controlling the movement of the mobile robot based on the estimated angle and position of the mobile robot.

[0010] Additionally, according to one embodiment of the present invention, the step of collecting data may further include a step of removing noise from the data collected in the data collecting step through an Extended Kalman Filter (EKF).

[0011] In addition, according to one embodiment of the present invention, the ultra-wideband device may be attached to the left and right ends of the door of each floor of the elevator at a distance greater than a preset distance, and may be positioned at a higher height than the ultra-wideband sensor attached to the mobile robot.

[0012] In addition, according to one embodiment of the present invention, the step of controlling the movement of the mobile robot may be a step of generating the movement of the mobile robot based on the estimated angle and position of the mobile robot, and controlling the movement of the mobile robot based on the sensing value measured through the ultrasonic sensor.

[0013] In addition, according to one embodiment of the present invention, the step of controlling the movement of the mobile robot may further include a step of determining an elevator from the side using a lidar sensor attached to the mobile robot and generating a boarding path for the mobile robot to enter the interior of the elevator, and a step of correcting the generated boarding path.

[0014] In addition, according to one embodiment of the present invention, the step of correcting the riding path may include detecting the surroundings in multiple directions by a plurality of ToF sensors attached to the mobile robot, comparing the distance values ​​to each detected obstacle, and correcting the generated riding path.

[0015] Additionally, according to one embodiment of the present invention, the step of recognizing the floor of the elevator may be a step of recognizing the floor of the elevator moving by receiving a unique identification ID assigned to ultra-wideband devices installed on each floor.

[0016] Additionally, according to one embodiment of the present invention, the step of the mobile robot getting off may be a step of determining whether the target floor has been reached by analyzing the received unique identification ID to determine whether the current location and the input target floor are the same.

[0017] In addition, according to one embodiment of the present invention, the method may further include, after the step of the mobile robot getting off, a step of checking whether a map of the floor on which the mobile robot got off exists that is stored in advance, loading the map, and displaying the current location of the mobile robot on the map by receiving an ultra-wideband signal of the floor.

[0018] In addition, an elevator inter-floor movement system for autonomous driving of a multi-story building based on ultra-wideband is disclosed according to one embodiment of the present invention. The system may include an elevator having a plurality of ultra-wideband devices attached to each floor, each having a unique ID, transmitting ultra-wideband signals, and a mobile robot that performs elevator boarding, floor recognition, and elevator alighting based on ultra-wideband signal data collected through the attached ultra-wideband sensors.

[0019] Specific details for achieving the above-mentioned purposes will become clear with reference to the embodiments described in detail below together with the attached drawings.

[0020] However, the present invention is not limited to the embodiments disclosed below, but can be configured in various different forms, and is provided to ensure that the disclosure of the present invention is complete and to fully inform a person having ordinary skill in the art to which the present invention pertains (hereinafter, “one skilled in the art”) of the scope of the invention.

[0021]

[0022] According to one embodiment of the present invention, the recognition rate in an elevator can be increased by using a distance measurement method using an ultra-wideband frequency.

[0023] In addition, according to one embodiment of the present invention, technology implementation is possible regardless of the elevator model through floor recognition by assigning a unique identification ID.

[0024] In addition, according to one embodiment of the present invention, since the exact location after getting off the elevator can be determined using an ultra-wideband frequency, the time required to find the initial location of the mobile robot after getting off the elevator can be shortened.

[0025] The effects of the present invention are not limited to the effects described above, and the tentative effects expected by the technical features of the present invention can be clearly understood from the description below.

[0026]

[0027] The features of the present invention described above may be more specifically and specifically understood by reference to the following examples, some of which are illustrated in the accompanying drawings. Furthermore, similar reference numerals throughout the drawings are intended to indicate the same or similar functionality throughout. However, the accompanying drawings illustrate only specific exemplary embodiments of the present invention and are not to be considered limiting of the scope of the present invention, as other equally effective embodiments may readily be realized.

[0028] FIG. 1 is a flowchart of a method for moving an elevator between floors by a mobile robot according to one embodiment of the present invention.

[0029] FIG. 2 is a diagram illustrating the result of removing noise through an extended Kalman filter collected in a step of collecting data according to one embodiment of the present invention.

[0030] FIG. 3 is a diagram illustrating a process for estimating the position of a mobile robot according to one embodiment of the present invention.

[0031] FIG. 4 is a diagram illustrating a process for estimating the direction angle of a mobile robot according to one embodiment of the present invention.

[0032] FIG. 5 is a drawing illustrating the creation of an elevator boarding path performed in a step of controlling the movement of a mobile robot according to one embodiment of the present invention.

[0033] FIG. 6 is a drawing illustrating an elevator boarding path correction performed in a step of controlling the movement of a mobile robot according to one embodiment of the present invention.

[0034]

[0035] To achieve the above objectives, a method for moving between elevator floors of a mobile robot for autonomous driving in a multi-story building based on ultra-wideband signals is disclosed according to one embodiment of the present invention. The method may include a step of the mobile robot boarding an elevator based on an ultra-wideband signal, a step of the mobile robot boarding the elevator recognizing the floor of the moving elevator, and a step of the mobile robot disembarking if the recognized floor is the target floor of the mobile robot.

[0036] In addition, an elevator inter-floor movement system for autonomous driving of a multi-story building based on ultra-wideband is disclosed according to one embodiment of the present invention. The system may include an elevator having a plurality of ultra-wideband devices attached to each floor, each having a unique ID, transmitting ultra-wideband signals, and a mobile robot that performs elevator boarding, floor recognition, and elevator alighting based on ultra-wideband signal data collected through the attached ultra-wideband sensors.

[0037]

[0038] The present invention can have various modifications and various embodiments, and specific embodiments are illustrated in the drawings and described in detail.

[0039] The various features of the invention disclosed in the claims can be better understood by considering the drawings and detailed description. The devices, methods, processes, and various embodiments disclosed in the specification are provided for illustrative purposes. The structural and functional features disclosed are intended to enable those skilled in the art to specifically implement various embodiments and are not intended to limit the scope of the invention. The terms and phrases disclosed are intended to easily explain the various features of the disclosed invention and are not intended to limit the scope of the invention.

[0040] In describing the present invention, if it is determined that a detailed description of a related known technology may unnecessarily obscure the gist of the present invention, the detailed description is omitted.

[0041] Hereinafter, a method and system for moving an elevator between floors of a mobile robot for autonomous driving in a multi-story building based on ultra-wideband according to one embodiment of the present invention are described.

[0042]

[0043] An elevator floor-to-floor movement system for a mobile robot may include an elevator and a mobile robot. The elevator floor-to-floor movement system for a mobile robot includes ultra-wideband devices attached to both ends of each floor of the elevator. The mobile robot recognizes the elevator floor through ultra-wideband signal transmission attached to each floor. When exiting the elevator, the ultra-wideband signal is used to estimate the location, making it easy to determine the initial current location of the mobile robot on a map for autonomous driving.

[0044] In one embodiment, the elevator may be equipped with an ultra-wideband device at both ends of each floor. The ultra-wideband devices attached to each end of each floor of the elevator may be positioned higher than the ultra-wideband sensor mounted on the mobile robot, taking into account the height of the ultra-wideband sensor mounted on the mobile robot. For example, the ultra-wideband devices may be positioned at a height of 2 m or more at both ends of the elevator door on each floor, and the ultra-wideband devices attached to each end may be installed while maintaining a distance of 2 m or more. The above examples are merely examples for describing the present disclosure, and the present disclosure is not limited thereto.

[0045] In one embodiment, the mobile robot can perform elevator boarding, floor recognition, and elevator disembarkation based on ultra-wideband signal data collected through an attached ultra-wideband sensor.

[0046] FIG. 1 is a flowchart of a method for moving an elevator between floors by a mobile robot according to one embodiment of the present invention.

[0047] In addition, FIG. 2 is a diagram showing the result of removing noise through an extended Kalman filter collected in a step of collecting data according to one embodiment of the present invention, FIG. 3 is a diagram showing a process of estimating a position of a mobile robot according to one embodiment of the present invention, and FIG. 4 is a diagram showing a process of estimating a direction angle of a mobile robot according to one embodiment of the present invention.

[0048] In addition, FIG. 5 is a drawing illustrating elevator boarding path generation performed in a step of controlling the movement of a mobile robot according to one embodiment of the present invention, and FIG. 6 is a drawing illustrating elevator boarding path correction performed in a step of controlling the movement of a mobile robot according to one embodiment of the present invention.

[0049] Referring to FIGS. 1 to 6, a method for moving between elevator floors (S1000) of a mobile robot may include a step (S1100) in which the mobile robot boards an elevator based on an ultra-wideband signal, a step (S1200) in which the mobile robot boarding the elevator recognizes the floor of the moving elevator, and a step (S1300) in which the mobile robot gets off if the recognized floor is the target floor of the mobile robot.

[0050] In one embodiment, the step of boarding an elevator (S1100) may be a step in which the mobile robot receives an ultra-wideband signal from an ultra-wideband device installed in the elevator, and the mobile robot boards the elevator based on the received ultra-wideband signal.

[0051] More specifically, the step of boarding an elevator (S1100) may include a step of the mobile robot collecting ultra-wideband frequency data transmitted from an ultra-wideband device attached to the elevator through an ultra-wideband sensor, a step of the mobile robot analyzing the collected ultra-wideband frequency data, a step of estimating an angle and position of the mobile robot based on the analyzed result, and a step of controlling the movement of the mobile robot based on the estimated angle and position of the mobile robot.

[0052] In one embodiment, the step of collecting data may be a step of the mobile robot collecting ultra-wideband frequency data transmitted from an ultra-wideband device attached to the elevator via an ultra-wideband sensor attached to the mobile robot.

[0053] Additionally, the step of collecting data may further include a step of removing noise from the ultra-wideband signal data of the elevator collected in the data collecting step through an Extended Kalman Filter (EKF).

[0054] Referring to Figure 2, Figure 2 is a drawing comparing initial data and Kalman filtered data at a distance of 5.5 m, and it can be seen that the Kalman filtered data has almost no noise compared to the initially collected data.

[0055] Here, the ultra-wideband device is attached to the left and right ends of the door on each floor of the elevator at a distance greater than a preset distance, and may be characterized in that it is located at a higher height than the ultra-wideband sensor attached to the mobile robot.

[0056] In one embodiment, the step of analyzing data may be a step of analyzing an ultra-wideband signal collected in the step of collecting data.

[0057] In one embodiment, the step of estimating the angle and position of the mobile robot may be a step of estimating the angle and position of the mobile robot based on the results analyzed through the step of analyzing data.

[0058] More specifically, positioning typically requires three or more linear distances to determine position coordinates. However, if the height of the ultra-wideband device and the height of the ultra-wideband sensor are known, coordinates can be determined on a plane using two linear distances.

[0059] Referring to Figures 3 and 4, the step of estimating the position of the mobile robot is

[0060] [Mathematical Formula 1]

[0061]

[0062] [Equation 2]

[0063]

[0064] [Equation 3]

[0065]

[0066] It can be calculated by the above mathematical formulas 1 to 3.

[0067] Here, r j is the distance data on the plane, R j is the distance from the ultra-wideband device, Z A is the height of the ultra-wideband device, Z T is the height of the mobile robot sensor, x is the x-coordinate on the plane, and y is the y-coordinate on the plane.

[0068] In addition, the step of estimating the heading angle of the mobile robot requires that there be two or more tags on the mobile robot to generate a path, and the heading angle of the mobile robot must be found out by the location of the tags.

[0069] Additionally, the step of estimating the direction angle of the mobile robot is

[0070] [Equation 4]

[0071]

[0072] It can be calculated by the above mathematical formula 4.

[0073] Here, θwheelchair is the orientation angle of the mobile robot, θ uwb is the UWB angle installed on an existing mobile robot. By comparing the positioning data applied to the two sensors attached to the existing mobile robot with the existing ultra-wideband mounting location using the positioning formula, the direction angle can be calculated and used as direction data for driving.

[0074] That is, by considering the height of the ultra-wideband device transmitted through the above mathematical expressions 1 to 4, the position and heading angle (the direction the mobile robot is facing) of the mobile robot can be estimated using two devices, and alignment for boarding the elevator can be performed using the estimated heading angle and position.

[0075] In one embodiment, the step of controlling the movement of the mobile robot may be a step of controlling the movement of the mobile robot based on the estimated angle and position of the mobile robot.

[0076] More specifically, the step of controlling the movement of the mobile robot may be a step of generating the movement of the mobile robot based on the estimated angle and position of the mobile robot, and controlling the movement of the mobile robot based on the sensing value measured through the ultrasonic sensor.

[0077] In addition, the step of controlling the movement of the mobile robot may further include a step of determining an elevator from the side using a lidar sensor attached to the mobile robot and generating a boarding path for the mobile robot to enter the elevator, and a step of correcting the generated boarding path.

[0078] The step of correcting the riding path may be a step of detecting the surroundings in multiple directions by multiple ToF sensors attached to the mobile robot, comparing the distance values ​​to each detected obstacle, and correcting the generated riding path.

[0079] More specifically, referring to FIGS. 5 and 6, the primary target point may deviate from the center position of the elevator due to sensor and odometry errors, which may lead to a collision with the elevator during boarding. To prevent this, as shown in FIG. 5, three ToF sensors capable of detecting the structure of the elevator in multiple directions are installed, and the separation distance between each sensor is set to 150 mm. ToF1 and ToF3 can be installed at an angle of magnitude θ, and ToF2 can be installed to look vertically toward the rear. The elevator boarding path correction algorithm using the three sensors above is as shown in FIG. 6. ToF2 is installed at a minimum safety distance d from the elevator wall. min2 It is used to proceed backwards until the ToF1 and ToF3 are maintained, and ToF1 and ToF3 can control the angular velocity for obstacle avoidance by comparing the distance values ​​to the detected obstacles.

[0080] In addition, the relationship between the minimum safe distance between the mobile robot and the wall is as shown in [Mathematical Formula 5] below, and d min1 is the minimum safe distance between the side of the wheelchair and the wall of the elevator shaft, d tof is d min1 This is the distance data value of the sensor to maintain the distance.

[0081] [Equation 5]

[0082]

[0083] In one embodiment, the step of recognizing the floor of the elevator (S1200) may be a step in which a mobile robot riding in the elevator recognizes the floor of the moving elevator.

[0084] More specifically, the step of recognizing the floor of the elevator (S1200) may be a step of recognizing the floor of the elevator moving by receiving a unique identification ID assigned to the ultra-wideband devices installed on each floor. The mobile robot can recognize the floor of the elevator by receiving a unique identification ID assigned to the ultra-wideband devices installed on each floor.

[0085] In one embodiment, the step (S1300) of the mobile robot getting off may be a step of the mobile robot getting off when the recognized floor is the target floor of the mobile robot.

[0086] More specifically, the step (S1300) of the mobile robot getting off may be a step of determining whether the target floor has been reached by analyzing the unique identification ID received through the step (S1200) of recognizing the floor of the elevator, and determining whether the current location and the input target floor are the same.

[0087] In addition, the method for moving between elevator floors (S1000) of a mobile robot may further include a step of checking whether a map of the floor on which the mobile robot got off exists after the step (S1300) of the mobile robot getting off, loading the map, and displaying the current location of the mobile robot on the map by receiving an ultra-wideband signal of the floor.

[0088] By receiving and analyzing ultra-wideband signals, the precise location of the mobile robot can be determined, which can be used to quickly find the initial location of the current mobile robot on the map.

[0089] The above description is merely an example of the technical idea of ​​the present invention, and those skilled in the art will be able to make various changes and modifications without departing from the essential characteristics of the present invention.

[0090] Accordingly, the embodiments disclosed in this specification are not intended to limit the technical idea of ​​the present invention, but rather to explain it, and the scope of the present invention is not limited by these embodiments.

[0091] The scope of protection of the present invention should be interpreted by the claims, and all technical ideas within the scope equivalent thereto should be understood to be included in the scope of the rights of the present invention.

Claims

1. In a method for moving an elevator between floors of a multi-story building using an ultra-wideband-based autonomous driving robot, A step in which the above mobile robot boards an elevator based on an ultra-wideband signal; A step for the mobile robot boarding the elevator to recognize the floor of the moving elevator; and If the above recognized floor number is the target floor of the mobile robot, a step of the mobile robot getting off is included. How to move an elevator between floors using a mobile robot.

2. In paragraph 1, The steps to board the above elevator are: A step of the above mobile robot collecting ultra-wideband frequency data transmitted from an ultra-wideband device attached to an elevator via an ultra-wideband sensor; The step of the above mobile robot analyzing the collected ultra-wideband frequency data; and A step of estimating the angle and position of the mobile robot through the above analyzed results; and A step of controlling the movement of the mobile robot based on the estimated angle and position of the mobile robot, How to move an elevator between floors using a mobile robot.

3. In paragraph 2, The steps for collecting the above data are: In the above data collection step, the method further includes a step of removing noise from the data collected through an Extended Kalman Filter (EKF). How to move an elevator between floors using a mobile robot.

4. In paragraph 2, The above ultra-wideband device, It is characterized in that it is attached at a distance greater than a preset distance to both sides of the entrance and exit doors of each floor of the elevator and is located at a higher height than the ultra-wideband sensor attached to the mobile robot. How to move an elevator between floors using a mobile robot.

5. In paragraph 2, The step of estimating the angle and position of the above mobile robot is, The position of the above mobile robot is estimated by [Mathematical Formula 1] to [Mathematical Formula 3], and the angle is estimated by [Mathematical Formula 4]. How to move an elevator between floors using a mobile robot. [Mathematical formula 1] [Mathematical formula 2] [Mathematical Formula 3] [Mathematical Formula 4] Here, r j is the distance data on the plane, R j is the distance from the ultra-wideband device, Z A is the height of the ultra-wideband device, Z T is the height of the mobile robot sensor, θwheelchair is the orientation angle of the mobile robot, θ uwb is the UWB angle installed on an existing mobile robot.

6. In paragraph 5, The step of controlling the movement of the above mobile robot is, A step of generating movement of the mobile robot based on the estimated angle and position of the mobile robot, and controlling the movement of the mobile robot based on the sensing value measured through the ultrasonic sensor. How to move an elevator between floors using a mobile robot.

7. In paragraph 6, The step of controlling the movement of the above mobile robot is, A step of determining an elevator from the side using a lidar sensor attached to the above mobile robot and generating a boarding path for the mobile robot to enter the inside of the elevator; and Further comprising a step of correcting the generated riding route, How to move an elevator between floors using a mobile robot.

8. In paragraph 7, The steps for correcting the above boarding route are: The surroundings are detected in multiple directions by multiple ToF sensors attached to the above-mentioned mobile robot, and the distance values to each detected obstacle are compared to correct the generated riding path. How to move an elevator between floors using a mobile robot.

9. In paragraph 1, The step of recognizing the floor number of the above elevator is: This is a step for recognizing the floor number of the elevator moving by receiving the unique identification ID assigned to the ultra-wideband devices installed on each floor. How to move an elevator between floors using a mobile robot.

10. In paragraph 9, The step where the above mobile robot gets off is: This is a step for determining whether the target layer has been reached by analyzing the unique identification ID received above and determining whether the current location and the input target layer are the same. How to move an elevator between floors using a mobile robot.

11. In paragraph 1, The above method, After the step of the above mobile robot getting off, the step of checking whether a map of the floor where the mobile robot got off exists in advance is further included, and then loading the map and displaying the current location of the mobile robot on the map by receiving an ultra-wideband signal of the floor. How to move an elevator between floors using a mobile robot.

12. In an elevator interfloor movement system of a mobile robot for autonomous driving in a multi-story building based on ultra-wideband, An elevator having multiple ultra-wideband devices attached to each floor, each having a unique ID, to transmit ultra-wideband signals; and A mobile robot that performs elevator boarding, floor recognition, and elevator disembarkation based on ultra-wideband signal data collected through an attached ultra-wideband sensor. Elevator interfloor movement system for mobile robots.

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