WO2023080723A1

WO2023080723A1 - Mobile robot and method for controlling mobile robot

Info

Publication number: WO2023080723A1
Application number: PCT/KR2022/017274
Authority: WO
Inventors: 김정은; 오종규; 김태현; 정인환; 이우재; 김기훈; 김윤석; 이윤혁; 김현대; 안슬비; 박가람; 옥도헌; 박형민
Original assignee: 현대로보틱스 주식회사
Priority date: 2021-11-05
Filing date: 2022-11-04
Publication date: 2023-05-11

Abstract

A mobile robot according to an embodiment of the present invention comprises: a body portion comprising a first frame and a second frame for fixing and supporting a tray; and a driving unit disposed at the lower end of the main body so as to generate a driving force capable of moving together with the main body, wherein the driving unit may comprise: a sensor unit capable of detecting a traveling state of the mobile robot; a drive output unit which generates a driving force so as to enable the mobile robot to move; and a drive control unit which controls the drive output unit so as to enable traveling at a preset travel speed, and adjusts the travel speed on the basis of the sensor unit.

Description

Mobile robot and mobile robot control method

The present invention relates to a mobile robot and a mobile robot control method.

As robot technology develops, robots are used in various fields. In particular, research on a robot that moves autonomously by recognizing surrounding objects according to a user's command is being actively conducted. For example, a robot that serves food and beverages to a designated table when a table number is entered, a robot that delivers towels, etc. to a designated room in an accommodation facility such as a hotel are being developed. In particular, the serving robot may move along a predetermined path within the store, but serves food while correcting the driving path so as not to collide with customers, other employees, or other serving robots.

The serving robot can travel on various paths within the store, and vibrations can occur depending on the condition of the floor of the store while driving. In this process, the prepared food may be disturbed, the beverage may overflow, or in severe cases, the container containing the beverage may topple over. In addition, even in the case of a serving robot used in an accommodation facility such as a hotel, food or water served in a designated room may be disturbed or overflowed, and towels or carriers loaded on the serving robot may fall over due to vibration. Problems can arise.

The present invention is to solve at least some of the problems of the prior art as described above, and to provide a mobile robot and a mobile robot control method for reducing vibration generated during driving.

In order to achieve the above object, a mobile robot according to an embodiment of the present invention includes a main body including a first frame and a second frame for fixing and supporting a tray, and disposed at a lower end of the main body, together with the main body. It includes a drive unit that generates a movable driving force, wherein the drive unit includes a sensor unit capable of detecting a driving state of the mobile robot, a drive output unit capable of moving the mobile robot by generating a driving force, and a driving speed set in advance. It may include a driving control unit that controls the drive output unit so as to travel and adjusts a travel speed based on the sensor unit.

The sensor unit may sense acceleration in at least a vertical direction.

The drive control unit may reduce the driving speed when the acceleration in the vertical direction is greater than or equal to a preset value.

The driving control unit may increase the traveling speed when the acceleration in the vertical direction is smaller than a preset value while driving at the reduced driving speed.

The body portion includes a first coupling member provided on side surfaces of the first frame portion and the second frame portion, a second coupling member provided on a lower surface of the tray and coupled to the first coupling member to fix the tray, and The tray fixing member disposed between the first coupling member and the tray to absorb vibration may be further included.

In order to achieve the above object, a mobile robot control method according to another embodiment of the present invention includes traveling at a preset speed, checking a vertical acceleration change occurring during driving, and comparing the acceleration change with a reference value. and adjusting a travel speed based on a difference between the amount of change in acceleration and a reference value.

In the adjusting of the traveling speed, the traveling speed may be reduced when the change in acceleration is greater than a reference value.

In the step of adjusting the driving speed, the step of traveling at the reduced driving speed, checking the amount of acceleration change in the vertical direction occurring during driving, and the step of comparing the amount of change in acceleration with a reference value are repeatedly performed, and the acceleration When the amount of change is smaller than the reference value, the method may further include driving at the preset driving speed.

The driving at the preset driving speed may include increasing the driving speed, traveling at the increased driving speed, checking a vertical acceleration change occurring during driving, and comparing the acceleration change with a reference value. The step is repeatedly performed, and the driving speed is reduced when the acceleration change amount is greater than the reference value, and the driving speed is increased when the acceleration change amount is smaller than the reference value while driving at the reduced driving speed. can include

The driving at the preset driving speed may include increasing the driving speed, traveling at the increased driving speed, and checking a change in acceleration in the vertical direction occurring during driving, comparing the change in acceleration with a reference value. and reducing the travel speed when the change in acceleration is greater than the reference value and increasing the travel speed when the change in acceleration is smaller than the reference value while driving at the reduced travel speed. It can be performed repeatedly until it is equal to or greater than the driving speed.

According to an embodiment of the present invention, by using a vibration absorbing member between the body frame and the tray, vibration generated by the road surface is not transmitted to the tray, so that serving items such as food transported through the tray can be served in a desired state. can

In addition, by adjusting the driving speed according to the condition of the road surface, vibration generation can be minimized even when driving on a road surface with uneven road surface conditions.

1 is a side view of a mobile robot according to an embodiment of the present invention.

2 is an enlarged view of a tray coupling part according to an embodiment of the present invention.

3 is a block diagram of a driving unit according to an embodiment of the present invention.

4 is a flowchart of vibration control of a mobile robot according to an embodiment of the present invention.

5 is a flowchart of vibration control of a mobile robot according to another embodiment of the present invention.

Since the present invention can make various changes and have various embodiments, specific embodiments are illustrated in the drawings and described in detail. However, this is not intended to limit the present invention to specific embodiments, and should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention.

Terms such as first and second may be used to describe various components, but the components should not be limited by the terms. These terms are only used for the purpose of distinguishing one component from another. For example, a first element may be termed a second element, and similarly, a second element may be termed a first element, without departing from the scope of the present invention. The term "and/or" includes any combination of a plurality of related listed items or any of a plurality of related listed items.

Terms used in this application are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this application, the terms "include" or "have" are intended to designate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, but one or more other features It should be understood that the presence or addition of numbers, steps, operations, components, parts, or combinations thereof is not precluded.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related art, and unless explicitly defined in this application, they should not be interpreted in an ideal or excessively formal meaning. don't

Hereinafter, embodiments of the present invention will be described in more detail with reference to the accompanying drawings.

1 is a side view of a mobile robot 100 according to an embodiment of the present invention.

Referring to FIG. 1 , a mobile robot 100 according to an embodiment of the present invention may include a main body 110 and a driving unit 160.

The body unit 110 may include a first frame unit 120 , a second frame unit 130 , a tray 140 , and a tray coupling unit 150 .

The first frame part 120 and the second frame part 130 may face each other and be formed in a direction substantially perpendicular to the ground. The first frame part 120 and the second frame part 130 are fixed to the tray 140 at both sides of the tray 140, and may support the weight of the article loaded on the tray 140.

The tray 140 is disposed between the first frame unit 120 and the second frame unit 130 to load items such as food. A plurality of trays 140 may be disposed at a predetermined height interval between the first frame unit 120 and the second frame unit 130 .

2 is an enlarged view of the tray coupling unit 150 according to an embodiment of the present invention.

Referring to FIG. 2 , the first frame portion 120 and the second frame portion 130 and the tray 140 coupling portion includes a first coupling member 151, a second coupling member 152, and a tray fixing member ( 153) may be included.

The first coupling member 151 may be disposed on the side of the first frame or the second frame. The first coupling member 151 may couple the tray 140 to the first frame or the second frame together with the second coupling member 152 .

The second coupling member 152 may be disposed on the lower surface of the tray 140 . The second coupling member 152 may fix the tray 140 to the first frame and the second frame together with the first coupling member 151 .

The tray fixing member 153 may absorb vibration generated from the road surface and transmitted to the tray 140 by inserting a vibration absorbing member between the first coupling member 151 and the tray 140 . The tray fixing member 153 may be made of synthetic resin or plastic material, but is not limited thereto.

Referring to FIG. 2 , the first coupling member 151 may be attached to a side surface of the first frame or the second frame. The second coupling member 152 may be provided on one side of the lower surface of the tray 140 . The tray fixing member 153 is disposed between the first coupling member 151 and the second coupling member 152, is interposed between the first coupling member 151 and the second coupling member 152, and absorbs vibration. It may also perform a role of combining the first coupling member 151 and the second coupling member 152.

Referring back to FIG. 1 , the driving unit 160 may be a device capable of moving the mobile robot 100 . 3 is a block diagram of a driving unit 160 according to an embodiment of the present invention. Referring to FIG. 3 , the driving unit 160 may include a sensor unit 161, a driving control unit 162, and a driving output unit 163.

The sensor unit 161 may be a sensor capable of checking the condition of the road surface, and may detect up and down vibration according to the condition of the road surface. The sensor unit 161 may be an inertial measurement unit (IMU) sensor. Here, the IMU sensor is composed of an acceleration sensor and an angular velocity sensor, and may further include a geomagnetic sensor. The IMU sensor can measure acceleration in the x-axis, y-axis, and z-axis directions. However, the sensor unit 161 is not limited to the IMU sensor, and various sensors capable of measuring vertical acceleration on the ground may be applied.

Also, the sensor unit 161 may detect the speed of the mobile robot 100 . The sensor unit 161 may include a speed sensor and directly measure the speed, based on the number of revolutions of a motor (not shown) of the driving unit 160 and the dynamic radius of the driving wheel. can also be calculated with

The drive control unit 162 can adjust the speed of the mobile robot 100 by controlling the drive output unit 163 based on the speed data of the mobile robot 100 received by the sensor unit 161 and the amount of change in the vertical direction. . The drive control unit 162 includes a non-volatile memory (not shown) configured to store data related to an algorithm configured to control the operation of various components of the mobile robot 100 or software instructions for reproducing the algorithm, and stored in the memory. It may be implemented through a processor (not shown) configured to perform operations described below using data. Here, the memory and the processor may be implemented as individual chips. Alternatively, the memory and processor may be implemented as a single chip integrated with each other. A processor may take the form of one or more processors. The driving control unit 162 may include an autonomous driving function.

The driving output unit 163 includes a motor (not shown), a power transmission engine, a driving wheel, and an auxiliary wheel, and is an integral body capable of moving together with the body unit 110 coupled to the top of the driving unit 160. may include a device of

Referring back to FIG. 1 , the mobile robot 100 may further include a display unit 170. The display unit 170 may be provided on top of the first frame unit 120 or the second frame unit 130 . The display unit 170 may output a preset image or video, include a touch panel, and function as an input unit capable of performing touch input. For example, in the case of a person who visits a store, he or she can check the menu through the screen displayed on the display unit 170, select the menu displayed on the display unit 170, and place an order. In addition, in the case of an employee of a store, a table displayed on the display unit 170 may be selected and ordered food or beverage may be served at the selected table.

4 is a vibration control flowchart of the mobile robot 100 according to an embodiment of the present invention.

Referring to FIG. 4 , the drive control unit 162 may control the drive output unit 163 so that the mobile robot 100 travels at a preset speed (S501). The drive control unit 162 may continuously or periodically receive data on acceleration, in particular, data on acceleration in the vertical direction (z-axis direction) on the ground through the sensor unit 161 while driving at a preset speed ( S502).

The driving control unit 162 may compare the amount of change in acceleration in the vertical direction on the ground with a preset reference value (S503). Here, the reference value is a value set in advance by the user, and may be a change in acceleration by which the mobile robot 100 can stably transfer the article on the tray 140 while driving. The reference value can be preset by the user through several test drives. The driving control unit 162 may continue to drive at a preset speed since the mobile robot 100 may stably transport the article when the amount of change in acceleration in the vertical direction is smaller than the reference value. The drive controller 162 controls the drive output unit 163 when the change in acceleration in the vertical direction is greater than or equal to the reference value when the change in acceleration in the vertical direction is greater than the reference value. The mobile robot 100 may travel by decelerating a predetermined speed from a preset speed (S504). Here, the size of the predetermined speed to be decelerated may be set by the user according to the size and situation of the store. The driving control unit 162 may reduce the influence of vibration generated on the mobile robot 100 by reducing the traveling speed.

The driving control unit 162 travels at the reduced speed and compares the amount of change in acceleration in the vertical direction on the ground with a preset reference value (S505). Here, the drive control unit 162 may return to step S504 when the change in acceleration in the vertical direction is greater than or equal to the reference value. That is, when the amount of change in acceleration in the vertical direction is greater than or equal to the reference value, the drive control unit 162 controls the drive output unit 163 to additionally reduce the traveling speed of the mobile robot 100 to a predetermined speed so as to travel. It can be done (S504). On the other hand, when the change in acceleration in the vertical direction is smaller than the reference value, the drive control unit 162 may determine that the condition of the road surface on which the mobile robot 100 is traveling has returned to normal, and may travel again at a preset speed. (S506).

5 is a vibration control flowchart of the mobile robot 100 according to another embodiment of the present invention.

In the present embodiment, detailed descriptions of technical features of S601 to S605 overlapping those previously described with reference to FIG. 4 will be omitted, and differences will be described in detail with reference to FIG. 5 .

In the case of the embodiment illustratively described in FIG. 5 , in the course of the mobile robot 100 traveling by reducing the travel speed, the drive control unit 162 returns to the preset speed when the amount of change in acceleration in the vertical direction is smaller than the reference value. There is a difference from the embodiment described in FIG. 4 in the driving process.

When the amount of change in acceleration in the vertical direction is smaller than the reference value, the drive control unit 162 controls the drive output unit 163 so that the mobile robot 100 can travel by increasing a predetermined speed from a preset speed ( S606). Here, the size of the increased speed may be set by the user according to the size and situation of the store. Also, the magnitude of the increased predetermined speed may be the same as the predetermined speed decreased in step S604, but is not limited thereto.

The driving control unit 162 travels at the increased speed and compares the amount of change in acceleration in the vertical direction on the ground with a preset reference value (S607). Here, the driving control unit 162 may return to step S604 again when the change in acceleration in the vertical direction is greater than or equal to the reference value. That is, when the amount of change in acceleration in the vertical direction is greater than or equal to the reference value, the drive control unit 162 controls the drive output unit 163 to reduce the traveling speed of the mobile robot 100 to a predetermined speed and travel. It can (S604). In the case where the road condition is temporarily stabilized and then enters the road surface where vibration occurs again, the speed of the mobile robot 100 is increased to a preset speed and then gradually increased without decelerating again, and the condition of the road surface is increased. When the condition of the road surface does not improve again while monitoring the speed, by reducing the speed, the speed change of the mobile robot 100 can be minimized and it can drive stably.

On the other hand, when the change in acceleration in the vertical direction is smaller than the reference value, the driving control unit 162 may determine that the condition of the road surface on which the mobile robot 100 is traveling has returned to normal, and may compare the driving speed with a preset speed. Yes (S608). If the driving speed is smaller than the preset speed, the driving speed may be additionally increased by returning to step S606. That is, the drive control unit 162 may repeatedly perform steps S606 to S608 until the speed of the mobile robot 100 recovers the preset speed.

The methods according to the present invention may be implemented in the form of program instructions that can be executed by various computer means and recorded on a computer readable medium. Computer readable media may include program instructions, data files, data structures, etc. alone or in combination. Program instructions recorded on a computer readable medium may be specially designed and configured for the present invention or may be known and usable to those skilled in computer software.

Examples of computer readable media include hardware devices specially configured to store and execute program instructions, such as ROM, RAM, flash memory, and the like. Examples of program instructions include high-level language codes that can be executed by a computer using an interpreter or the like as well as machine language codes generated by a compiler. The hardware device described above may be configured to operate with at least one software module to perform the operations of the present invention, and vice versa.

A mobile robot and a mobile robot control method according to an embodiment of the present invention use a vibration absorbing member between a body frame and a tray to prevent vibration generated by a road surface from being transmitted to the tray, such as food transported through the tray. The serving item may be served in a desired state.

In addition, the mobile robot and the mobile robot control method according to an embodiment of the present invention can adjust the driving speed according to the condition of the road surface, and reduce the speed when driving on a road surface with an uneven road surface to prevent vibration. can be minimized.

In addition, the mobile robot and the mobile robot control method have been described mainly for robots serving food, but are not limited thereto. For example, a mobile robot may deliver food while driving on a general road outside a building, or it may be a robot that delivers milk or newspaper delivery to a predetermined destination, so it can be applied to various fields. .

Although the above has been described with reference to examples, those skilled in the art can variously modify and change the present invention without departing from the spirit and scope of the present invention described in the claims below. You will understand.

100 ... mobile robot 110 ... main body

120 ... first frame portion 130 ... second frame portion

140 ... tray 150 ... tray coupling part

151 ... first coupling member 152 ... second coupling member

153 ... tray fixing member 160 ... driving unit

161 ... sensor unit 162 ... drive control unit

163 ... drive output unit 170 ... display unit

Claims

A body portion including a first frame and a second frame for fixing and supporting the tray; and

a drive unit disposed at a lower end of the body unit to generate a driving force capable of moving with the body unit;

including,

the driving unit,

a sensor unit capable of detecting a driving state of the body unit;

a drive output unit generating a driving force enabling the main body to move; and

a driving control unit controlling the driving output unit so as to travel at a preset driving speed, and adjusting the driving speed based on the driving state detected by the sensor unit;

including,

mobile robot.
According to claim 1,

The sensor unit detects acceleration in the vertical direction,

mobile robot.
According to claim 2,

The driving control unit,

Decreasing the travel speed when the acceleration in the vertical direction is greater than a preset value,

mobile robot.
According to claim 2,

The driving control unit,

Increasing the traveling speed when the acceleration in the vertical direction is less than a preset value while traveling at the reduced traveling speed.

mobile robot.
According to claim 1,

The body part,

A first coupling member provided on the side surfaces of the first frame unit and the second frame unit;

a second coupling member provided on a lower surface of the tray and coupled to the first coupling member to fix the tray; and

a tray fixing member disposed between the first coupling member and the tray to absorb vibration;

Including more,

mobile robot.
traveling at a preset speed;

Checking a change in acceleration in a vertical direction that occurs during driving;

comparing the amount of change in acceleration with a reference value; and

adjusting a traveling speed based on a difference between the amount of change in acceleration and a reference value;

Mobile robot control method comprising a.
According to claim 6,

In the step of adjusting the driving speed,

Decreasing the traveling speed when the acceleration change amount is greater than the reference value,

How to control a mobile robot.
According to claim 7,

In the step of adjusting the driving speed,

driving at a reduced driving speed and checking a change in acceleration in a vertical direction generated during driving; and

comparing the amount of change in acceleration with a reference value;

is performed repeatedly,

traveling at the preset travel speed when the change in acceleration is smaller than the reference value;

Including more,

How to control a mobile robot.
According to claim 8,

The step of traveling at the preset travel speed,

increasing the running speed;

Checking a change in acceleration in a vertical direction that occurs during driving; and

comparing the amount of change in acceleration with a reference value;

is performed repeatedly,

reducing the travel speed when the change in acceleration is greater than the reference value, and increasing the travel speed when the change in acceleration is smaller than the reference value while driving at the reduced travel speed;

Including more,

How to control a mobile robot.
According to claim 9,

The step of traveling at the preset travel speed,

increasing the running speed;

driving at an increased driving speed and checking a change in acceleration in a vertical direction generated during driving;

comparing the amount of change in acceleration with a reference value; and

reducing the travel speed when the change in acceleration is greater than the reference value, and increasing the travel speed when the change in acceleration is smaller than the reference value while driving at the reduced travel speed;

including,

Repeatedly performing until the driving speed is equal to or greater than the preset driving speed,

How to control a mobile robot.