MOBILE ROBOT AND METHOD FOR CONTROLLING IT

Description

Technical Field

[0001] Embodiments of the present disclosure relate to a moving robot that is configured to drive a work area and may enhance location tracking accuracy, and a control method thereof.Disclosure Technical Problem

[0002] A robot has developed for industrial use and played some part of factory automation. Recently, the fields applying the robot have been expanded such that a robot for medical used, a space aerial robot and other robots have developed. Even a home robot that may be used for general home has developed. One robot capable of driving on its own among such the robots may be called 'a moving robot'.

[0003] Specifically, such a moving robot may perform work while autonomously driving even without a user's manipulation. The location recognition of the moving robot is required to facilitate the autonomous driving of the moving robot. Typically, a current location of the robot may be recognized based on information about the map of the moving robot driving and diverse sensor data.

[0004] A cited reference (Korean Open-Laid Patent No. 10-2016-0026991, published on March 19th, 2016) discloses a method for determining location of a radio frequency (RF) transmitter under multipath inference. However, it is difficult to determine whether the transceived signal is a Line of Sight (LOS) by using only one sensor that is disclosed in the cited reference.

[0005] In other words, it is difficult to recognize the accurate location recognition of the moving robot based on the NLOS signal in the RF-based location recognition and determine whether the transceived signal is NLOS or LOS by using the single sensor.

[0006] US 2018 / 052466 A1 presents a real-time navigating method for mobile robot. The method comprises the following steps of: retrieving a target position at a mobile robot; receiving a position signal from an external beacon device by an ultra-wideband communication module and calculating a current position of the mobile robot; calculating a moving direction according to the target position and the current position; calibrating the moving direction when detecting any obstacle by a laser range sensing module and moving towards the calibrated moving direction for dodging the obstacle; and, repeatedly executing above detection, calibration and movement until arriving the target position.

[0007] KR 100 575 706 B1 relates to a system and method for returning a robot cleaner to a charging station, wherein an RF signal generating means is mounted on the charging station, a directional RF antenna is attached to the robot cleaner, and the shortest distance to the charging station without obstacles is detected using the directional RF antenna and an ultrasonic sensor, thereby allowing the robot cleaner to quickly return to the charging station. The charging station has an RF signal generating means, which generates an RF signal for guiding a robot cleaner to the charging station; and a robot cleaner which, in the charging station return mode, rotates in an arbitrary direction, detects an RF signal generated from the charging station, detects a distance to the charging station based on the intensity of the detected RF signal, compares the detected distance with a distance to the charging station detected by an ultrasonic sensor, and detects the shortest path to the charging station based on the result of the comparison.

[0008] US 2018 / 098676 A1 relates to a cleaning robot docking to a station based on a radio frequency (RF) signal and a method of controlling the same. The cleaning robot comprises a cleaning robot antenna unit configured to receive a radio frequency (RF) signal transmitted from a station; and a controller configured to extract a received signal strength indicator (RSSI) value by processing the RF signal received by the cleaning robot antenna unit and control movement of the cleaning robot to dock to the station based on the extracted RSSI value.Technical Solutions

[0009] Accordingly, an object of the present disclosure is to address the above-noted and other problems of the conventional moving robot.

[0010] Another object of the present disclosure is to provide a moving robot including a RF receiver configured to track a distance and a radio direction to calculate a radio direction between the receiver and a RF beacon installed in a robot driving area and extract a distance sensor tracking area based on the result of the calculated radio direction and a tracking error and then to compare the calculated distance between the beacon and the receiver with the result of the distance sensor tracking such that the location accuracy of the moving robot may be enhanced by using some beacon information that is corresponding to the location estimation when the result of the comparison satisfies a predetermined condition.

[0011] Specifically, the beacon radio direction may be tracked during the driving of the moving robot and a beacon distance and information about the distance sensor may be compared with respect to the corresponding radio direction and it may be determined based on the result of the comparison whether there is an obstacle. Accordingly, the moving robot may be determined whether to apply the beacon radio direction information to the location estimation. The object of the present disclosure is to provide such the moving robot and a control method thereof.

[0012] Accordingly, embodiments of the present disclosure provides a control method of a moving robot configured to drive a work area where are a plurality of beacons, the control method comprising a radio direction acquiring step of acquiring radio direction information from the beacons; a first distance tracking step of tracking first distance information between the moving robot and the beacons based on the radio direction information, after the radio direction acquiring step; a second distance tracking step of tracking second distance information between the moving robot and an object existing in the work area via a distance sensor provided in the moving robot; and a first comparison step of comparing the first distance information with the second distance information, wherein location recognition of the moving robot is performed based on the radio direction information, when the first distance is equal to the second distance based on the result of the first comparison step.

[0013] The second distance tracking step may be performed after the first distance tracking step.

[0014] The method of the moving robot further comprises a second comparison step of comparing a difference between the first distance and the second distance with a predetermined value, when the first distance is different from the second distance based on the result of the first comparison step. Location recognition of the object is performed based on the second distance information, when the first distance is larger than the second distance based on the result of the second comparison step.

[0015] After the location recognition of the object, location recognition of the moving robot may be performed by sequentially performing the radio direction acquiring step, the first distance tracking step, the second distance tracking step and the first comparison step while the moving robot is driving.

[0016] When the first distance is smaller than the second distance based on the result of the second comparison step, the radio direction acquiring step may be performed and the location recognition of the moving robot is performed by sequentially performing the first distance tracking step, the second distance tracking step and the first comparison step.

[0017] Embodiment of the present disclosure may also provide a method of the moving robot configured to drive a work area where a plurality of beacons are installed, the control method comprising a radio direction acquiring step of acquiring radio direction information from the beacons; a first distance tracking step of tracking first distance information between the moving robot and the beacons based on the radio direction information, after the radio direction acquiring step; an area setting step of setting a first area in the radio direction of the beacons via a camera module provided in the moving robot; a second distance tracking step of tracking second distance information between the moving robot having moved a preset distance in the first area and an object existing in the work area by triangulation, after the area setting step and; a first comparison step of comparing the first distance information with the second distance information, wherein location recognition of the moving robot is performed based on the radio direction information, when the first distance is equal to the second distance based on the result of the first comparison step.

[0018] The second distance tracking step may be performed after the first distance tracking step.

[0019] The control method of the moving robot may further a second comparison step of comparing a difference between the first distance and the second distance with a predetermined value, when the first distance is different from the second distance based on the result of the first comparison step. Location recognition of the object may be performed based on the second distance information, when the first distance is larger than the second distance based on the result of the second comparison step.

[0020] After the location recognition of the object, location recognition of the moving robot may be performed by sequentially performing the radio direction acquiring step, the first distance tracking step, the second distance tracking step and the first comparison step while the moving robot is driving.

[0021] When the first distance is smaller than the second distance based on the result of the second comparison step, the radio direction acquiring step may be performed and the location recognition of the moving robot is performed by sequentially performing the first distance tracking step, the second distance tracking step and the first comparison step.

[0022] Embodiment of the present disclosure may also provide a moving robot comprising a body that defines an exterior design; a plurality of wheels provided in both sides of the body, respectively, and configured to move the body; a motor configured to provide a torque to the plurality of the wheels; a communication unit provided in the body and configured to receive radio direction data from a beacon installed in a work area where the body moves; a distance sensor provided in the body and configured to track a distance between the body and an object existing in the work area; a calculation unit configured to compare a first distance extracted between the body and beacons based on the radio direction data with a second distance tracked between the body and the object via the distance sensor; and a controller configured to perform location recognition of the body based on the radio direction data, when the first distance is equal to the second distance, wherein the controller performs location recognition of the body based on the radio direction data, when the first distance is equal to the second distance.

[0023] The controller may recognize the object as the beacon, when the first distance is equal to the second distance.

[0024] The controller may recognize the object as an obstacle, when the first distance is larger than the second distance.

[0025] Embodiments of the present may also provide a moving robot comprising a body that defines an exterior design; a plurality of wheels provided in both sides of the body, respectively, and configured to move the body; a motor configured to provide a torque to the plurality of the wheels; a communication unit provided in the body and configured to receive radio direction data from a beacon installed in a work area where the body moves; a camera module provided in the body and configured to photograph a video near the body; a calculation unit configured to set a first area in the beacon radio direction in the video photographed via the camera module and comparing a first distance extracted between the body and the beacon based on the radio direction data and a second distance tracked between the body and the object based on location change of the body in the first area; and a controller configured to perform location recognition of the body based on the radio direction data, when the first distance is equal to the second distance, wherein the controller performs location recognition of the body based on the radio direction data, when the first distance is equal to the second distance.

[0026] Accordingly, the embodiments have following advantageous effects.

[0027] According to at least one embodiment of the present disclosure, the moving robot may enhance the location recognition accuracy of the moving robot driving the working area, with the plurality of the beacons installed therein.

[0028] In addition, the moving robot may distinguish the LOS (Ling of Sight) signal and the NLOS (None Line of Sight) signal from the other signals transceived for the location estimation of the moving robot driving in the working area and the LOS signal may be used in the location estimation of the moving robot. Accordingly, the moving robot may enhance the location recognition accuracy.

[0029] Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter.Description of Drawings

[0030] The present invention will become more fully understood from the detailed description given herein below and the accompanying drawings, which are given by illustration only, and thus are not limitative of the present invention, and reference numerals means structural elements and wherein: FIG. 1 is a perspective diagram of a moving robot according to one embodiment of the present disclosure; FIG. 2 is a diagram of FIG. 1, viewed from the bottom; FIG. 3 is a block diagram illustrating a structure of the moving robot according to one embodiment; FIG. 4 is a control flow chart according to one embodiment of the present disclosure; FIG. 5 is a diagram illustrating one example of the control method shown in FIG. 4; FIG. 6 is a control flow chart according to another embodiment; and FIG. 7 is a diagram illustrating one example of the control method shown in FIG. 6. Best Mode

[0031] Description will now be given in detail according to exemplary embodiments disclosed herein, with reference to the accompanying drawings. The following description is used to help easily understand the method, device and / or system and it should be understood that the embodiments presented herein are not limited by the description.

[0032] For the sake of brief description with reference to the drawings, the same or equivalent components may be provided with the same reference numbers, and description thereof will not be repeated. In the present disclosure, that which is well-known to one of ordinary skill in the relevant art has generally been omitted for the sake of brevity. As such, the present disclosure should be construed to extend to any alterations, equivalents and substitutes in addition to those which are particularly set out in the accompanying drawings. Terminology that is used in the present disclosure is limited to only for embodiments herewith but made only to make it easy to understand the present disclosure. A singular representation may include a plural representation unless it represents a definitely different meaning from the context. Terms such as "include" or "has" are used herein and should be understood that they are intended to indicate an existence of several components, functions or steps, disclosed in the specification, and it is also understood that greater or fewer components, functions, or steps may likewise be utilized.

[0033] It will be understood that although the terms first, second, A, B, (a), (b), etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are generally only used to distinguish one element from another. These terms are generally only used to distinguish one element from another.

[0034] FIG. 1 is a perspective diagram of a moving robot according to one embodiment of the present disclosure and FIG. 2 is a diagram of FIG. 1, viewed from the bottom.

[0035] Hereinafter, the embodiment will be described, referring to FIGS. 1 and 2.

[0036] The moving robot 1 according to the embodiment may include a body 10 that defines the exterior design and the body 10 may define an inner space. The moving robot 1 may include a wheel 20 configured to move the body 10 along a driving surface. The moving robot 1 may include a blade 30 configured to perform a lawn mowing work while the body 10 is moving along a driving surface.

[0037] In other words, the moving robot 1 according to the embodiment is described under the premise that it should be a moving robot for mowing lawn. Here, a control method for the location estimation of the moving robot which will be described later may not be necessarily limited to the moving robot for moving lawn.

[0038] Meanwhile, the body 10 may include a frame 11 that defines a bottom of the moving robot 1 and fixes a wheel 20, a motor 21 and a blade 40 thereto. A blade motor for providing a torque to the blade 30 may be fixedly mounted to a bottom surface of the frame 11. The frame 11 may provide a frame structure to support other various components.

[0039] A caster (not shown) may be arranged in the frame 11 to rotatably support an additional wheel 22. The caster may be rotatable with respect to the frame 11 and rotate on a vertical shaft. The caster may be arranged under the frame 11. A pair of casters may be provided to correspond to a pair of additional wheels 22.

[0040] The frame 11 may include a case 12 to cover a top of the body 10 such that it may define an internal space of the moving robot 1. The case 12 may define an upper surface, a front surface, a rear surface and right and left surfaces.

[0041] The body 10 may include a case connecting part (not shown) configured to fix the case 12 to the frame 11. The case 12 may be fixed to an upper end of the case connecting part. The case connecting part may be movable along the frame 11. Here, the case connecting part may be movable with respect to the frame 11 only in a vertical direction and it may be movable only in a p redetermined distance range. As the case connecting part is integrally moving with the case 12, the case 12 may be also movable with respect to the frame 11.

[0042] The body 10 may include a bumper 12a arranged in a front area the bumper 12a installed in the front surface of the moving robot 1 may function to absorb shock if the moving robot 1 collides against or contacts with an obstacle outside during the driving. The bumper 12a may have a front surface and right and left side surfaces that are connected with each other to cover some area of the front and side surface of the body 10. The front surface and the side surfaces may be roundly connected with each other. The bumper 12a may be made of a predetermined material that is available in absorbing shock (e.g., rubber).

[0043] The body 10 may include a handle 13. The handle 13 may be arranged in a rear area of the case 12. The handle 13 may be a part that is configured to be held by the user in the hand. Such relatively heavy parts are provided in the rear area of the moving robot 1 as the wheel 20, the motor 21, a batter (not shown). Accordingly, the user may hold the handle 13 arranged in the rear area of the case 12 more stably.

[0044] The body 10 may include a batter cover 14 configured to facilitate a battery (not shown) embedded in the moving robot 1 to be moved in or out. The battery cover 14 may be arranged in a lower surface of the frame 11. It may be also arranged in a rear area of the frame 11.

[0045] The body 10 may include a power switch 15 for switching on and off the power of the moving robot 1. The power switch 15 may be arranged in the frame 11.

[0046] The body 10 may further include a blade cover 16 configured to cover a lower center area of the blade 30. The blade cover 16 may be configured to cover the center of the blade 30 while a centrifugal direction area of the blade is exposed.

[0047] The blade 30 may be rotatable one a shaft 30r to mow the lawn by using the centrifugal-direction blade. Accordingly, the moving robot 1 according to the embodiment may prevent a safety accident that the user using the moving robot 1 might be hurt by the blade 30. In addition, it may prevent the overload of the blade motor (not shown) that might occur because of the lawn foreign substances stuck to the shaft of the blade 30.

[0048] The body 10 may include a first cover 17 configured to open and close the area accommodating a height adjusting part 31 and a height displaying 33. The first cover 17 may be hingedly coupled to the case 12 to rotatably perform the opening and closing. The first cover 17 may be provided in an upper surface of the case 12. The first cover 17 may be formed in a plate shape and cover respective tops of the height adjusting part 31 and display 33, in a state of being closed. The first cover 17 may be made of a transparent material to allow the user to check the display 33, in a state of being closed.

[0049] The moving robot 1 may adjust the height of the blade 30 with respect to the ground. Accordingly, the moving robot 1 may change the height for mowing the lawn during the driving. The height adjusting part 31 may be configured to facilitate the height change of the blade 30 and provided as a rotary dial. To change the height of the blade 30, the user may open the first cover 17 and rotate the height adjusting part 31 to change the height of the blade 30.

[0050] The display 33 may be configured to display a height level of the blade 30. When the height of the blade 30 is changed based on the user's manipulation of the height adjusting part 31, the heigh level displayed on the height display 33 is correspondingly changed. As one example, the height display 33 may display a height value of lawn that is expected after the moving robot 1 mows lawn, with the blade 30 having the current height.

[0051] The body 10 may include a second cover 18 provided to open and close the area accommodating a display module 38 and an input unit 35. The second cover 18 may be hingedly coupled to the case 12 to perform the opening and closing. The second over 18 may be provided in an upper surface of the case 12 and arranged behind the first cover 17. The second cover 18 may be formed in a plate shape and cover the display module 37 and the input unit 35, in a state of being closed. The second cover 18 may be made of a transparent material to allow the user to check the display module 37, in a state of being closed.

[0052] An openable angle of the second cover 18 may be set to be smaller than an openable angle of the first cover 17. Then, the user may be allowed to easily open the first cover 17 and manipulate the height adjusting part 31, in a state of the second cover 18 being open. Also, the user may be allowed to easily the contents displayed on the height display 33 with naked eyes, in a state of the second cover being open.

[0053] Accordingly, the first cover may be open after a rear end is upwardly lifted with respect to a front end. The second cover 18 may be open after a rear end is upwardly lifted with respect to a front end. The opening of the first and second covers 17 and 18 may be set not to be interfered with each other.

[0054] The display module 37 may be arranged in an upper surface of the case 12 and configured to output information towards the user. As one example, the display module 37 may include an LCD (Thin film transistor Liquid Crystal Display) panel. In addition, the display module 37 may be realized by using a plasma display panel, an organic light emitting diode display panel or other various display panels.

[0055] The input unit 35 may include a button, a dial and a touch panel. In addition, the input unit 35 may include a microphone (not shown) configured to recognize a voice. The input unit 35 according to the present embodiment may be configured of a plurality of buttons that are arranged in the upper surface of the case 12.

[0056] The wheel 20 may include a left wheel 20a provided in a left side of the moving robot 1 and a right wheel 20b provided in a right side of the moving robot 1. Such a pair of wheels may be spaced a preset distance apart from each other to right and left and arranged in a rear lower area of the body 10. The pair of the wheels may be independently rotatable. As one example, when the two wheels are rotating at the same speed, the body 11 may move forward or backward with respect to the ground. When the wheel 20a and the wheel 20b are rotating at different speeds, the body 11 may rotate with respect the ground.

[0057] In other words, the wheel 20 may be configured to directly affect the driving of the moving robot 1.

[0058] The wheel 20 may be provided with the power by the motor 21. The motor 21 may include a motor 21a configured to provide the power to the wheel 20a; and the other motor 21b configured to provide the power to the other wheel 20b, which are spaced a preset distance apart from each other to right and left. The motor 21 may be arranged in a lower rear area of the body 11.

[0059] In the present embodiment, the wheel 20a and the other wheel 20 may be directly connected to a shaft of the motor 21a and a shaft of the other motor 21b, respectively. Alternatively, the wheels may have additional elements such as the shaft or provided with the torque of the motors 21a and 21b via a gear or chain.

[0060] An additional wheel 22 may be configured to support the body 11 with respect the ground, together with the wheel 20, and arranged in a front lower area of the body 11. The additional wheel 22 of the present embodiment may be arranged in front of the blade 30. The additional wheel 22 may not be provided with the driving power of the motor. The additional wheel may additionally support the body 11 with respect to the ground. The caster for supporting a shaft of the additional wheel 22 may be rotatably coupled to the frame 11 and rotatable with respect to a vertical axis. The additional wheel 22 may include a left additional wheel 22a arranged in a left side and a right additional wheel 22b arranged in the right side.

[0061] FIG. 3 is a block diagram illustrating the structure of the present disclosure according to one embodiment.

[0062] Hereinafter the structure will be described, referring to FIGS. 1 through 3.

[0063] A front sensor 42 may be arranged in a front area of the body 10 and a rear sensor 41 may be arranged in a rear area of the body 10.

[0064] The front sensor 41 may be arranged in a front area of the moving robot 1 and configured to receive a remote signal that is transmitted from the front and transmit a signal to a rear area of the moving robot.

[0065] The rear sensor 41 may be arranged in a rear area of the moving robot 1 and configured to receive the remote signal transmitted from the rear area and transmit the signal to the rear area of the moving robot.

[0066] The moving robot 1 may include a communication unit 40 configured to communicate with an external terminal 8, a server and a router. The communication unit 40 may be realized to facilitate wireless communication between the moving robot 1 and the external terminal 8 and the like via a wireless communication technique (e.g., UWB, Wi-Fi, Bluetooth and etc.). The communication unit 40 may be realized as a different type based on the device it is designed to communicate with or a communication method of the server.

[0067] An ultra-Wide Band wireless digital pulse (hereinafter, 'UWB') may be applied to the present embodiment as the wireless short-range communication means. The UWB module has some advantages in terms of the speed, power consumption, distance tracking accuracy and penetration such that it may have advantages as the sensor configured to track a relative distance of the moving robot 1. However, the communication means of the present embodiment may not be limited to the UWB module. Diverse wireless communication techniques may be applicable.

[0068] The front sensor 42 may include an obstacle sensor that is arranged in the front area of the moving robot 1 in a main driving direction and configured to sense an obstacle. The obstacle sensor may sense an obstacle that is on a driving direction line of the moving robot 1 or located near the moving robot 1. Examples of such the obstacle sensor may include an infrared ray sensor, an ultrasonic wave sensor, a RF sensor, a geometric sensor and a PSD (Position Sensitive Device) sensor.

[0069] As one example of the obstacle sensor, the present embodiment may include a distance sensor 51 and a camera sensor 53. The distance sensor 51 may be configured to measure a relative distance with an obstacle that is located on a main driving route of the moving robot 1 and recognize present of an obstacle located on the driving route based on the result of the measurement. The camera module 53 may be configured to photograph a video having a predetermined azimuth on the main driving direction route of the moving robot 1 and recognize the present of the obstacle based on analysis of a controller 4 or a calculation unit 65.

[0070] In addition, a cliff sensor 52 may be provided in the front area of the body 10 in the main driving direction of the moving robot 1 and configured to sense a relative distance with the bottom surface. The cliff sensor 52 may sense the height of the moving robot with respect to the driving surface or the amount of the light reflected and incident from the driving surface.

[0071] The azimuth sensor 55 may have a Gyro-sensing function. The radio direction sensor 55 may further have an acceleration sensing function. The radio direction sensor 55 may include a Gyro sensor 55a and an acceleration sensor 55b to perform respective functions.

[0072] The Gyro sensor 55a may be configured to sense the horizontal rotation speed of the body 10. The Gyro sensor 55a may sense a tilt speed with respect to the horizontal surface of the body. And have a Gyro sensing function for three axes that are orthogonal to each other in a space coordinate system. The information collected by the Gyro sensor 55a may include Roll, Pitch and Yaw. Each of the angular velocities is integrated to calculate a direction angle of the moving robot 1.

[0073] The acceleration sensor 55b may have the acceleration sensing function for the three axes that are orthogonal to each other in the space coordinate system. A predetermined processing module may integrate the acceleration to calculate the velocity and the velocity may be integrated to calculate a moving distance.

[0074] The azimuth sensor 55 may sense a bottom surface having a big drop, which exists on the driving surface of the moving robot 1, together with the cliff sensor 52.

[0075] A GPS sensor 56 may be provided to sense a GPS (Global Positioning System) signal. The GPS sensor 56 may be realized by using a PCB loaded in an electric control installed in the moving robot 1. The location of the moving robot 1 may be found outdoor by the GPS sensor 56.

[0076] Rather than the above-noted sensors, other components for the driving control of the moving robot 1 and communication with an external module may be provided in the electric control unit. The electric control unit may be installed in the moving robot 1. The electric control unit may be installed based on the performance of the moving robot 1 or the category of each moving robot brand, before manufactured and released for sales.

[0077] The moving robot may drive a work area based on the control of the controller 6 for the drive unit 7.

[0078] The drive unit 7 may include a first motor 21 configured to transmit the power to the wheel 20 to facilitate the driving of the moving robot 1 and a second motor 23 configured to transmit the power to the blade 30. The first motor 21 and the second motor 23 may be controlled independently.

[0079] As one example, when the moving robot 1 is driving in a work area for mapping, the power supplied by the first motor 21 may be needed but the power supplied by the second motor 23 may not be needed. In other words, when the mapping of the work area or no lawn exists in the work area, only the first motor 21 may be driven during the driving of the moving robot 1.

[0080] More specifically, the mapping will be described. The moving robot may not move directly in an initial work area map acquiring step. Instead, a UWB device may be mounted to a roller and map information of the work area may be acquired (hereinafter, 'the roller mapping') or the map information of the work area may be acquired while the user is walking around a border of the work area, with holding an anchor (hereinafter, 'the anchor mapping'). In other words, diverse methods may be used in the map making or acquiring step of the initial work area.

[0081] FIG. 4 is a control flow chart of the moving robot according to one embodiment and FIG. 5 is a diagram illustrating one example of the control method shown in FIG. 4.

[0082] Hereinafter, the embodiment will be described, referring to FIGS. 4 and 5.

[0083] In the control method of the moving robot 1 according to this embodiment, a LOS (Line of Sight) signal may be distinguished from a NLOS (None Line of Sight) signal in the radio direction information transmitted from the plurality of the beacons installed the work area where the moving robot is driving, so as to enhance the accuracy of the moving robot location tracking. Accordingly, the location of the moving robot 1 may be tracked based on the LOS signal.

[0084] The LOS means a straight signal that is transmitted from at least one of the beacons installed in the work area to the moving robot 1. Generally, the LOS signal is a signal having the shortest distance from the beacons to the moving robot 1.

[0085] The NLOS signal means a signal that is transmitted not directly to the moving robot 1 but to the moving robot 1 along a farther rough than the shortest route by an obstacle or other external factors out of the signals transmitted to the moving robot 1.

[0086] Accordingly, the NLOS signal may mean the signal that always travel along a farther route than the LOS signal.

[0087] The moving robot 1 of the present embodiment may start driving towards a work area or start driving in the work area. As mentioned above, the moving robot 1 may receive the signal from the beacon B installed in the work area and perform the location recognition of the moving robot 1 based on the received signal. Accordingly, the moving robot 1 may be located in the work area before acquiring the radio direction data of the beacon B.

[0088] Accordingly, once it starts the driving in the work area, the moving robot 1 may acquire beacon radio direction information S12. Specifically, the radio direction information transmitted from the beacon may be transmitted to the moving robot 1 via the communication unit 40 arranged in the front or rear area of the moving robot 1. The received radio direction information may be stored in a memory 61.

[0089] After the radio direction acquiring S12, the first distance tracking step S13 for tracking information about a first distance between the moving robot 1 and the beacon B.

[0090] The radio direction information transmitted from the beacon B may include information about various directions or ranges from a transmitted reference point. In the present embodiment, the first distance information about the distance between the moving robot and the beacon B may be extracted from the above-noted radio direction information to perform the location recognition of the moving robot 1. The first distance tracking step S13 may be performed by the calculation unit 65 according to the present embodiment.

[0091] Hence, a second distance tracking step S14 may be performed to track information about a second distance between moving robot 1 and an object O existing in the work area by using the distance sensor 51 provided in the moving robot 1.

[0092] The second distance tracking step S14 may be performed after the first distance tracking step S13. Alternatively, the second distance tracking step S14 may be performed before the first distance tracking step S13. When the distance information is acquired via respective different routes before performing the comparison between the acquired information, it may be satisfactory.

[0093] Specifically, only when the respective first and second distance information are acquired before a comparison step for comparing the first distance information tracked in the first distance tracking step S13 with the second distance information tracked in the second distance tracking step S14, the performance order of the first distance tracking step S13 and the second distance tracking step S14 may be changed.

[0094] It may be preferred that the first distance tracking step S13 and the second distance tracking step S14 are performed at the same time. It may expect a more precise result of the location tracking in tracking the current location of the moving robot 1 to simultaneously perform the two distance tracking steps.

[0095] Meanwhile, a first comparison step S161 for comparing g the first distance information and the second distance information with each other may be performed after acquiring the first distance information and the second distance information. The first comparison step S161 may compare and determine whether the first distance information is equal to the second distance information.

[0096] The when the first distance information is equal to the second distance information based on the result of the first comparison step S161, it may mean that there is no obstacle between the beacon B and the moving robot 1 and that the direction signal transmitted from the beacon B is the LOS signal.

[0097] Accordingly, in case the first distance is equal to the second distance based on the result of the first comparison step S161, the direction information of the beacon B may be stored in the memory S17 and the location recognition of the moving robot may be performed based on the direction information of the beacon S18.

[0098] When the first distance is different from the second distance based on the result of the first comparison step S161, it may mean that there is an obstacle O between the beacon B and the moving robot 1 or the direction signal transmitted from the beacon B is the NLOS signal because of the obstacle O located between the beacon B and the moving robot 1 or other external factors.

[0099] Accordingly, if the first distance is different from the second distance based on the result of the first comparison step S161, the second comparison step S162 for comparing such a difference with a predetermined value may be performed.

[0100] The second comparison step S162 may be configured to compare relative differences of the first distance and the second distances with each other, while the first comparison step S161compares them to figure out whether the first and second distances are equal to each other.

[0101] When the first distance is larger than the second distance in the second comparison step S162, the first distance information may mean that there an obstacle between the beacon B and the moving robot 1 and that the direction information signal transmitted from the beacon B is the NLOS signal that travels along a farther route than the shortest route between the moving robot 1 and the beacon B because of the obstacle O.

[0102] Accordingly, when the first distance is larger than the second distance based on the result of the second comparison step S162, the location recognition may be performed based on the second distance information. The object may be the obstacle O in the present embodiment.

[0103] After the location recognition of the obstacle is performed based on the second distance S163, the moving robot may drive away from the obstacle O. The process described above for the location recognition of the moving robot may be performed again.

[0104] Meanwhile, when the first distance is smaller than the second distance based on the result of the second comparison step S162, the radio direction acquiring step S12 may be performed and the first distance tracking step S13, the second distance tracking step S14 and the first comparison step S161 may be sequentially performed to perform the location recognition of the moving robot 1.

[0105] As one example that the first distance is smaller than the second distance in the second comparison step S162, it may be premised that external factors act to the moving robot while tracking the second distance to the object O via the distance sensor or trasceiving the signal via the communication unit only to cause a sudden location change.

[0106] Specifically, when the first distance is smaller than the second distance, the acquiring of the radio direction information about the beacon B may be re-performed and the above-noted process for the precise location recognition of the moving robot may be then re-performed.

[0107] As describing the structure of the present embodiment for the above-noted control flow chart in detail, the moving robot according to this embodiment may include the body 10 that defines the exterior design; the plurality of the wheels 20a and 20b provided in both sides of the body 10 and configured to rotate and move the body 10; the motor 21 configured to provide the torque to the wheels; the communication unit 40 provided in the body and configured to receive the radio direction information from the beacon installed in the work area where the body is moving; the distance sensor 51 provided in the body 10 and configured to track the distance between the body 10 and an object located in the work area; the calculation unit 65 configured to compare a first distance extracted between the body and the beacon based on the direction information with a second distance measured between the body and the object via the distance sensor 51; and the controller 4 electrically connected with the communication unit 40 and the calculation unit 65. The controller 4 may perform the location recognition of the body based on the direction information when the first distance is equal to the second distance.

[0108] FIG. 6 is a control flow chart according to another embodiment and FIG. 7 is a diagram illustrating one example of the control method shown in FIG. 6.

[0109] Referring to FIG. FIG. 5, the embodiment will be described. Here, repeated description will be omitted, compared with the embodiment shown in FIG. 4.

[0110] This embodiment is provided to enhance the location recognition accuracy of the moving robot by comparing the distance information acquired in respective different routes, similar to the embodiment shown in FIG. 4.

[0111] The control method of the embodiment may include an area setting step S24 for setting a first area in the beacon radio direction via the camera module 53 after extracting the first distance information corresponding to the beacon radio direction.

[0112] After the area setting step S24, a second distance tracking step S26 may be performed to tracking the second distance information between moving robot 1 having moved a preset distance in the first area set in the area setting step S24 and the object O existing in the work area by triangulation.

[0113] In other words, after area of interest is extracted from the video photographed via the camera module 53 in the beacon direction, the moving robot 1 may move by the unit length. The distance between the object O and the moving robot 1 may be measured by the triangulation with respect to the area of the interest in the video via the calculation unit 65. In this embodiment, the distance between the object O and the moving robot 1 may be defined as the second distance.

[0114] The first comparison step S271 may be performed to compare with the first distance with the second distance, when the second distance information is acquired in the second distance tracking step S26 and the first distance information is acquired in the first distance tracking step S23. The following description may be equally applied to the embodiment shown in FIG. 4.

[0115] Specifically, this embodiment is a control method applying a different method of tracking the second distance, compared with the embodiment shown in FIG. 4. The embodiment shown in FIG. 4 uses the distance sensor 51 to track the second distance. This embodiment uses the camera module 53 to measure the second distance.

[0116] As describing the structure of this embodiment to the above-noted control flow chart in detail, the moving robot may include the body 10 defining the exterior design; the plurality of the wheels 20a and 20b provided in both sides of the body 10, respectively, and configured to move the body 10; the motor 21 configured to provide the torque to the wheels; the communication unit 40 provided in the body and configured to receive radio direction information from the beacon installed in the work area where the body 10 moves; and the camera module 53 provided in the body 10 and configured to photograph a video near the body.

[0117] The moving robot may further include the calculation unit 65 configured to extract the first distance between the body 10 and the beacon B based on the radio direction information and set a first area in the radio direction of the beacon B in the video photographed via the camera module 53 and compare the first distance with the second distance between the body and the object based on the location change of the body in the first area; and the controller 4 electrically connected with the calculation unit 65 and configured to perform the location recognition of the body 10. The controller may perform the location recognition of the body based on the radio direction information, when the first distance is equal to the second distance.

[0118] The scope of the invention is defined by the appended claims.

Claims

1. A control method of a moving robot configured to drive a work area in which a plurality of beacons are installed, the control method comprising: a radio direction acquiring step (S12) of acquiring radio direction information from the beacons; a first distance tracking step (S13) of tracking first distance information between the moving robot and the beacons based on the radio direction information, after the radio direction acquiring step; and a second distance tracking step (S14) of tracking second distance information between the moving robot and an object existing in the work area via a distance sensor (51) provided in the moving robot; characterized in that, the control method further comprising: a first comparison step (S161) of comparing the first distance information with the second distance information, wherein location recognition of the moving robot is performed based on the radio direction information, when the first distance is equal to the second distance based on the result of the first comparison step, and a second comparison step (S162) of comparing a difference between the first distance and the second distance with a predetermined value, when the first distance is different from the second distance based on the result of the first comparison step, wherein location recognition of the robot with respect to the object is performed based on the second distance information when the first distance is larger than the second distance based on the result of the second comparison step (S162), wherein the second distance information is determined after determining the first distance information.

2. The control method of the moving robot of claim 1, wherein the second distance tracking step is performed after the first distance tracking step.

3. The control method of the moving robot of claim 1, wherein after the location recognition of the object, location recognition of the moving robot is performed by sequentially performing the radio direction acquiring step, the first distance tracking step, the second distance tracking step and the first comparison step while the moving robot is driving.

4. The control method of the moving robot of claim 1, wherein when the first distance is smaller than the second distance based on the result of the second comparison step, the radio direction acquiring step is performed and the location recognition of the moving robot is performed by sequentially performing the first distance tracking step, the second distance tracking step and the first comparison step.

5. The control method of the moving robot of claim 1, wherein the second distance between the moving robot and the object is determined using a video of a camera module provided in the moving robot, and wherein the second distance tracking step of the second distance between the robot and the object includes: an area setting step of setting a first area in the radio direction of the beacons; a second distance tracking step of tracking second distance information between the moving robot having moved a preset distance in the first area and the object existing in the work area by triangulation, using the video of the camera module, after the area setting step.

6. A moving robot comprising: a body (10) that defines an exterior design; a plurality of wheels (20a, 20b) provided in both sides of the body (10), respectively, and configured to move the body (10); a motor (21) configured to provide a torque to the plurality of the wheels (20a, 20b); a communication unit (40) provided in the body (10) and configured to receive radio direction data from a beacon installed in a work area where the body (10) moves; a distance sensor (51) provided in the body and configured to track a distance between the body and an object existing in the work area; a calculation unit (65) configured to: determine a first distance between the body (10) and beacons based on the radio direction data, determine a second distance between the body (10) and the object based on the data collected by the distance sensor (51), and compare the first distance and the second distance; and a controller (4) configured to perform location recognition of the body (10) based on the radio direction data, when the first distance is equal to the second distance, wherein the controller (4) performs location recognition of the body (10) with respect to the object based on the second distance, when the first distance is larger than the second distance, and wherein the controller (4) is configured to determine the second distance after determining the first distance.

7. The moving robot of claim 6, wherein the controller (4) is configured to recognize the object as the beacon, when the first distance is equal to the second distance.

8. The moving robot of claim 6, wherein the controller (4) is configured to recognize the object as an obstacle, when the first distance is larger than the second distance.