KR101475826B1 - Leader-Follower Formation Device, Method and Mobile robot using Backstepping Method - Google Patents

Abstract

A large control device, method and mobile robot for a lead follower using a back stepping technique are disclosed. The input unit senses the position of the leading robot. The control unit calculates the position information of the leading robot and the position information of the follower robot using the position sensed by the input unit and controls the movement of the follower robot using the calculated position information of the leading robot and the calculated position information of the follower robot .

Description

TECHNICAL FIELD [0001] The present invention relates to a large-sized follower control device, a method, and a mobile robot using a back-stepping technique,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a large-sized control of a mobile robot, and more particularly, to a large-sized control device, a method, and a mobile robot for a leading robot and a follower robot.

Currently, mobile robots are used in various fields. In many fields, such as industry, medicine, and service, human beings are in a difficult position to work. In recent years, research using multiple robots has been actively pursued rather than a single robot.

As with human beings, robots can be used more and more efficiently. In particular, robots for crime prevention and patrols can search a large area that a single robot can not afford through a plurality of robots. In the case of a transport robot, a plurality of robots can carry heavy loads that a single robot can not carry.

Many robots not only move toward the target, but also perform the task while maintaining a constant distance and angle between the robots. In this way, maintaining a certain distance and angle with respect to a target or another robot is called a formation of a multi-robot and a method of controlling the same is referred to as a large-scale control of a multi-robot.

There are three major methods of large-scale control: behavior-based approach, virtual structure approach, and leader-follower approach.

The behavior-based approach is to control the speed and direction of the mobile robot by weighting each robot's behavior, such as avoiding obstacles and avoiding collisions between large-sized robots, do.

In the virtual structure approach, a certain size is set in advance, and the large body is made into a rigid body having one structure, and its object tracking, path tracing, obstacle avoidance, and the like are controlled, And performs control on the robot. However

The lead follower approach is to maintain the large size of the leading robot and to follow the leading robot by using the distance between the leading robot and the leading robot. The advantage is that it is able to express the dynamics of the mobile robots and it is possible to design the controller that is analytically stable.

However, the behavior - based approach is difficult to express in terms of dynamics of mobile robots and it is difficult to guarantee analytical stability.

In the case of the virtual structure approach, it is easy to maintain stable large size, but it is difficult to control the dispersion according to the characteristics of each robot existing in the large size.

Since the lead follower approach designs the controller of the follower by interpreting the robots on the absolute coordinates like follow - up control, various constraints are imposed on implementation through practical experiment. The follower robot must know the speed and angular velocity of the leading robot in real time, and the position on the coordinate must be grasped.

Therefore, when the experiment is performed using the existing lead - follower approach, the real - time coordinates, velocity, and angular velocity of the robots must be obtained through sensors that measure the absolute position and transmitted to the follower robots. However, when performing various tasks such as method and patrol in industry or in the field, it is difficult to achieve such real-time absolute positioning and communication.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a large-sized control device, a method, and a mobile robot of a mobile robot that maintains the size of a plurality of mobile robots.

It is another object of the present invention to provide an apparatus and method for controlling movement of a mobile robot that calculates the positions of a plurality of mobile robots and controls movement of the mobile robots.

According to an aspect of the present invention, there is provided a large follower follower controller using a back stepping method,

And a controller for calculating the position information of the leading robot and the position information of the follower robot using the position sensed by the input unit and the position information of the calculated leading robot and the calculated position information of the following leader robot, And a controller for controlling the movement of the follower robot using the position information.

The input unit may include at least one of a camera unit including at least one camera for capturing an image of the lead robot and a sensor unit including at least one sensor for sensing the distance of the lead robot.

The camera and the sensor may be installed in the follower robot, respectively.

Wherein the control unit calculates a target point based on the calculated position information of the leading robot and the calculated position information of the follower robot and calculates a linear velocity required for the follower robot to move to the target point on the basis of the calculated target point And the rotation speed can be calculated.

The controller calculates an error between the follower robot and the target point on the basis of the calculated position information of the follower robot and the calculated target point and calculates the linear velocity and the rotation velocity based on the calculated error .

The control unit may calculate a torque for driving the wheels of the follower robot to move the follower robot to the target point based on the calculated linear velocity and the rotation speed.

The controller may calculate the torque using at least one of the mass, inertia, centripetal force, frictional force, and gravity of the follower robot.

A large-scale control mobile robot,

A leading robot for leading a follower robot in front of the large size, and a follower robot for moving to a target point for maintaining a constant size with the leading robot, wherein the follower robot includes an input unit for sensing the position of the leading robot, Calculates the position information of the leading robot and the position information of the follower robot using one position and controls the movement of the follower robot using the position information of the calculated leading robot and the calculated position information of the follower robot And a control unit.

The lead robot includes at least one landmark, the input unit captures an image of the landmark, and the control unit can calculate position information of the leading robot using the image of the captured landmark.

The large follower control method using the back stepping technique,

Detecting the position of the leading robot using a camera or a sensor installed in the follower robot, calculating position information of the leading robot and position information of the follower robot on the basis of the detected position of the leading robot, Calculating a target point of the follower robot based on the position information of the leading robot and the calculated position information of the follower robot and calculating an error between the current position and the target point of the follower robot on the basis of the calculated target point Calculating a linear velocity and a rotation velocity necessary for the follower robot to move to a target point on the basis of the calculated error, calculating a linear velocity and a rotation velocity necessary for the follower robot to move to a target point of the follower robot on the basis of the calculated linear velocity and the calculated rotation velocity Calculating the torque for driving the wheels of the follower robot to make the wheels Wherein on the basis of the calculated torque follower robots may include the step of moving to a target point.

According to the large-sized follower control device, method and mobile robot using the back stepping technique according to the present invention, stability of the mobile robot can be satisfied by implementing a large-scale control by kinematics and dynamics, and using a back stepping method.

In addition, the follower robot can easily cope with the real situation in real situation by using the parameter sensed through the sensor.

In addition, the follower robot can maintain its size in areas where communication is impossible by using the relative distance and angle of the camera.

1 is an exemplary diagram of a large control in accordance with an embodiment of the present invention.
2 is a block diagram of a large control apparatus according to an embodiment of the present invention.
3 is a block diagram of a controller according to an embodiment of the present invention.
FIG. 4 is an exemplary view showing the size and coordinates of a target and a mobile robot according to an embodiment of the present invention.
5 is an exemplary diagram illustrating a simulation of a quadrangular pattern running according to an embodiment of the present invention.
FIG. 6 is an exemplary view showing an error of the follower robot position and direction in FIG.
FIG. 7 is an exemplary diagram showing the linear velocity and the rotational velocity of the follower robot of FIG. 5;
8 is an exemplary diagram showing a simulation of an R-pattern running according to an embodiment of the present invention.
FIG. 9 is an exemplary view showing an error with respect to the follower robot position and direction in FIG.
10 is an exemplary diagram showing the linear velocity and the rotational velocity of the follower robot of FIG.
11 is a diagram illustrating an example of a leading robot and a follower robot according to an embodiment of the present invention.
FIG. 12 is a diagram illustrating an actual implementation of large-scale control of a leading robot and a follower robot according to an embodiment of the present invention.
Fig. 13 is an exemplary diagram showing an error with respect to the position and direction of the mobile robot in Fig. 12;
FIG. 14 is a flowchart illustrating a process of performing a large control method according to an embodiment of the present invention.
15 is a flowchart illustrating a process of performing a large control method according to another embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals are used to designate the same or similar components throughout the drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather obvious or understandable to one skilled in the art.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. When the mobile robot refers to moving or calculating "coordinates" or "location information" or "points"

1 is an exemplary diagram of a large control in accordance with an embodiment of the present invention.

Referring to FIG. 1, the large control may include a leading robot 110 and at least one follower robot. In addition, when the lead robot 110 moves, the follower robot can also move to maintain its size.

The leading robot 110 may be a large control reference for the follower robot 1 120 and the follower robot 2 130. [ If the leading robot 110 moves to the moving point 110 'during the large-scale control of the mobile robots, the follower robot 1 120 and the follower robot 2 130 move to the target point 1 120 of the follower robot 120 'And target point 2 130'. The follower robot 1 120 and the follower robot 2 130 can move to the target point 1 120 'and the target point 130' by the lead follower large control using the back stepping technique.

The leading robot 110 may include at least one landmark, and the landmark may indicate the position of the line robots 110. The follower robot 1 120 and the follower robot 2 130 may be provided with at least one web camera capable of photographing a landmark of the leading robot 110. Also, the follower robot 1 120 and the follower robot 2 130 may include at least one relative position measurement sensor such as a sonar. The follower robot 1 120 and follower robot 2 130 can calculate the position information of the landmark by using the web camera and the sensor and generate the large control and torque of the leading robot and the follower robot through the calculated position information, Control can be performed. The leading robot 110, the follower robot 1 120 and the follower robot 2 130 may be a model including at least one of a kinematic model and a dynamic model.

The model of mobile robot can be divided into kinematic model and dynamic model. The kinematic model shows the linear velocity and the rotational speed with respect to the mechanical characteristics of the mobile robot, and the dynamic model includes the physical characteristics of the mobile robot such as mass, centripetal force, frictional force, inertia and torque. The present invention can use a practical control input for obtaining the torque applied to both wheels of the mobile robot using the two models and controlling the movement of the mobile robot according to the movement of the object.

2 is a block diagram of a large control apparatus according to an embodiment of the present invention.

2, the large-size control apparatus 1 may include at least one of an input unit 210, a control unit 220, an output unit 230, and a storage unit 240. The large control device 1 can use a lead follower approach to maintain a certain distance and angle of the mobile robot. Also, the large control device 1 can calculate the distance and direction error between the follower robot 1 (120) and the follower robot 2 (130) to the target point by using the coordinates of the leading robot 110 obtained in real time.

The input unit 210 may include at least one of a camera unit 211 and a sensor unit 212. The camera unit 211 can be installed in the follower robot and can capture a landmark indicating the coordinates of the leading robot.

The sensor unit 212 can be installed in the follower robot and can sense the position of the landmark indicating the coordinates of the leading robot.

The camera unit 211 is a camera installed in the follower robot, and may include at least one camera. The camera unit 211 may be any type that does not affect movement of a mobile robot such as a web camera. In addition, the camera unit 211 can be fixed to make the photographing angle constant.

The sensor unit 212 is a sensor installed in the follower robot, and may include at least one sensor. The sensor unit 212 may be any type capable of relative position measurement, such as a sonar. A sonar can fire an ultrasonic wave as a short intermittent sound, measure the time it takes to hit the object, reflect and return, and calculate the distance to the object. Further, the sensor unit 212 can be fixed so as not to affect the follower robot.

The leading robot 110 can provide the reference coordinates to the follower robot 1 120 and the follower robot 2 130 using landmarks. The landmark may include position information of the leading robot. The landmark can also be fixed so that the leading robot does not affect movement.

The control unit 220 may include at least one of a first control unit 221 for calculating position information of the mobile robot and a second control unit 222 for performing a large control and a torque control of the follower robot. The control unit 220 can control the formation and movement of the leading robot and the follower robot.

The first control unit 221 can calculate the coordinates of the leading robot using the camera unit 211 and the sensor unit 212 of the follower robot. Also, the first controller 221 can determine the coordinates of the leading robot as reference coordinates, and calculate the coordinates of the follower robot based on the reference coordinates.

The second control unit 222 can control the movement while maintaining the size using the position information of the mobile robot calculated by the first control unit 221. [ The second control unit 222 can calculate the target point of the follower robot according to the movement of the lead robot. The second control unit 222 may calculate the straight line and the rotation speed to the target point of the follower robot by calculating the error between the current position and the target point of the follower robot. The second control unit 222 can calculate the accurate torque using the calculated straight line and rotational speed.

The output unit 230 can move to the target point by generating torque using the calculated number of torques.

The storage unit 240 may store the distance and the direction angle of the leading robot and the target point of the follower robot to be maintained.

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

Referring to FIG. 3, the controller 120 may control the leading robot and the follower robot to move while maintaining a large size.

The first control unit 121 may include at least one of the leading robot position information calculation unit 210 and the follower robot position information calculation unit 220.

The first control unit 121 can calculate the coordinates of the leading robot using the image captured by the camera unit 211. [ The leading robot position information calculation unit 310 can calculate the position information of the landmark installed in the leading robot captured by the camera unit 211. [ The calculated position information of the landmark may be the coordinates of the leading robot, and may be the reference coordinates of the follower robot. Also, since the landmark also moves when the leading robot moves, the reference coordinates of the follower robot may also be relatively changed.

The follower robot position information calculation unit 320 can calculate the coordinates of the follower robot using the image information captured by the camera unit 211 based on the coordinates of the leading robot calculated by the leading robot position information calculation unit 310 have.

The first controller 121 can calculate the coordinates of the leading robot and the follower robot using the distance sensed by the sensor unit 212. [ The leading robot position information calculation unit 310 can calculate the coordinates of the leading robot using the sensed distance information from the sensor unit 212. [

The follower robot position information calculation unit 320 can calculate the coordinates of the follower robot using the distance information sensed by the sensor unit 212 based on the leading robot coordinates calculated by the leading robot position information calculation unit 310 .

The first control unit 121 may control at least one of the leading robot and the landing robot using at least one of a method using an image picked up by the camera unit 211, a method using a distance sensed by the sensor unit 212, The position information of the follower robot can be calculated.

The second control unit 122 may include at least one of the large control unit 330 and the torque control unit 340. The second control unit 122 may use a vector including at least one of a linear velocity and a rotational velocity of the mobile robot and a vector including at least one of mass, inertia, centripetal force, friction force, gravity and torque of the mobile robot. The second control unit 122 may set the control input of the mobile robot as an actual physical torque control input rather than a speed.

The large control unit 330 can control the follower robot to maintain its size with the leading robot. The large control unit 330 can calculate the target point of the follower robot using the coordinates of the leading robot and the follower robot calculated by the first control unit 121. [ The large control unit 330 can calculate the target point using the back stepping technique considering stability and can calculate the target point using the parameters obtained through the relative position measuring sensor of the follower robot. The target point is a point at which the follower robot must move in order to maintain the formation as the leading robot moves. The large control unit 330 can calculate the error between the current position and the target point of the follower robot. Also, the large controller 330 can calculate the straight line and the rotation speed to the target point of the follower robot using the error.

The torque control unit 340 can calculate the torque using information obtained by calculating the straight line and the rotation speed from the large control unit 330 to the target point. Accordingly, the torque control unit 340 calculates the torque for driving the left and right wheels of the follower robot to move the follower robot to the target point, so that the leading robot and the follower robot can maintain their size.

FIG. 4 is an exemplary view showing the size and coordinates of a target and a mobile robot according to an embodiment of the present invention. FIG. 4 shows the representation of the target point 430 and the coordinates of the follower robot 420 'in the leading robot coordinates 410'.

는 선도 로봇(410)과 추종자 로봇(420) 사이의 거리이고,

는 선도 로봇(410)에서부터 추종자 로봇(420)의 위치까지의 각도이다.

,

는 추종자 로봇의 좌표(420')를 나타내고,

및

는 각각 추종자 로봇(420)의 진행방향 및 목표 지점(430)과 추종자 로봇(420) 사이의 진행방향 오차를 나타낼 수 있다.

,

는 선도자 로봇 좌표(410')에서 추종자 로봇 좌표(420')를 나타낼 수 있으며,

,

는 목표 지점(430)의 위치를 나타낼 수 있다.

,

는 선도자 로봇(410)과 유지해야 하는 목표 지점(430)의 거리와 방향각이 될 수 있고, 저장부(240)에 저장될 수 있다. 선도자 로봇의 좌표(410')로 표현된 파라미터들을 이용하여 추종자 로봇(420)이 목표 지점(430)에 도달할 수 있게 한다.Referring to Figure 4,

Is the distance between the leading robot 410 and the follower robot 420,

Is the angle from the leading robot (410) to the position of the follower robot (420).

,

Represents the coordinates 420 'of the follower robot,

And

Can indicate the traveling direction of the follower robot 420 and the traveling direction error between the target point 430 and the follower robot 420, respectively.

,

May represent the follower robot coordinates 420 'in the leader robot coordinates 410'

,

May indicate the location of the target point 430. [

,

May be a distance and a direction angle between the guiding robot 410 and a target point 430 to be maintained and may be stored in the storage unit 240. The follower robot 420 can reach the target point 430 using the parameters represented by the coordinates 410 'of the leader robot.

는 다음의 수학식(1)로 나타낼 수 있다.The error between the target point 430 of the follower robot and the coordinates 420 'of the follower robot

Can be expressed by the following equation (1).

Equation (2) can be seen to include the term for the error of Equation (1) and the coordinates 420 'of the follower robot as a derivative with respect to Equation (1).

,

을 다음의 수학식(3)과 같이 설계할 수 있다. In the present invention, by using the equation (2)

,

Can be designed as the following equation (3).

,

,

에 대한 이득 값인

,

,

는 양한정(Positive definite)일 수 있다. 만약

,

,

가 양한정(Positive definite)이면, 추종자 로봇(420)의 직선속도

와 회전속도

가 수학식(3)의 제어 입력을 가지고,

을 만족하면 점근적으로 안정화될 수 있다.Equation (3) shows that the errors for each axis and direction are included.

,

,

Gt;

,

,

Can be positive definite. if

,

,

(Positive definite), the linear velocity of the follower robot 420

And rotation speed

Has the control input of Equation (3)

, It can be stabilized asymptotically.

와 각도

에 위치한 목표 지점(430)를 추종하여 대형을 유지할 수 있다. 대형 제어부(330)는 추종자 로봇의 목표 지점

및 영상정보로 취득한 추종자 로봇의 위치

를 이용하여, 산출된 오차를 통해

를 설계할 수 있다. The follower robot 420 is moved from the lead robot 410 by a predetermined distance

And angle

The target point 430 can be maintained in a large size. The large control unit 330 controls the target point of the follower robot

And the position of the follower robot acquired as the image information

Through the calculated error

Can be designed.

The large control unit 330 may be an auxiliary input of the torque control unit 340. The large control unit 330 can control the generation of the torque for driving the left and right wheels of the mobile robot. Such a torque input may include at least one of a kinematic model of a mobile robot and a mass and a centripetal force by a dynamic model.

The control unit 220 can perform a large-scale control of the mobile robot using a backstepping technique in which the stability of the relay is considered. The back stepping method is a nonlinear dynamic system having a recursive structure for stabilization control. Unlike the control part of the existing lead follower approach method, the present invention does not consider information such as the absolute position and velocity of the leading robot 410, but only the parameters obtainable through the relative position measuring sensor in the follower robot 420 The control unit 220 can be designed.

5 is a diagram illustrating a simulation of a square pattern movement according to an embodiment of the present invention.

의 값을 계산하였고, 관성 모멘트

는 이동로봇이 원통이라는 가정하에 계산하였다. 이동로봇의 물리적 요소값은 표1과 같다.
Referring to FIG. 5, the value of the physical element of the mobile robot used in the simulation is the value of the mobile robot. The physical element value assumes that the center of the mobile robot length is the center of gravity

And the moment of inertia

Is calculated under the assumption that the mobile robot is a cylinder. The physical element values of the mobile robot are shown in Table 1.

Physical element Abbreviation value mass m 9kg Moment of inertia I 0.2278 kg.m ² Wheel radius r 0.0925m Robot width 2W 0.38m Distance between center of gravity and center of wheel axis d 0.0505m

5 shows a large-scale control of the follower robot 1 540 and the follower robot 2 550 when the target robot 510 moves in a quadrangular trajectory. Also, the simulation can confirm the large control performance for the target point 1 520 and the target point 2 530 of the follower robot 1 (540) and the follower robot 2 (550) through a rectangular trajectory pattern.

The follower robot 1 540 maintains the target point 1 520 on the left side of the lead robot 510 and the follower robot 2 550 maintains the target point 1 520 on the left side of the lead robot 510, And moves to the target point 2 (530) from the right side of the target point. The leading robot 510 also shows the movement of straight and right rotation (0 to 50 seconds), rapid 90 ° direction change (50 seconds), and straight and left rotation (50 to 100 seconds).

를 유지하고, 우회전 속도

, 좌회전 속도

이다.
At this time, the speed of the leading robot 510 is the linear speed

And the right turn speed

, Left turn speed

to be.

FIG. 6 is an exemplary view showing an error of the follower robot position and direction in FIG.

축 오차,

축 오차 및 방향

의 오차 중 적어도 하나를 보여줄 수 있다. Referring to FIG. 6, graphs 610, 620, 630, and 640 illustrate

Axis error,

Axial error and direction

The error of at least one of.

The graph 610 is a position error graph of the follower robot 1 540 and the graph 620 is a direction error graph of the follower robot 1 540. The graph 630 is a position error graph of the follower robot 2 550 and the graph 640 is a direction error graph of the follower robot 2 550.

In the graph 610 and the graph 630, a large error occurs because there is a difference to the initial position in the early stage, but the error decreases with time. The graph 620 and the graph 640 show errors due to the sudden change of direction of the leading robot 510 in 50 seconds, but the error decreases with time. Also, the graphs 620 and 640 show that the direction errors caused by the physical factors of the moment of inertia continue when the straight line and the rotational movement occur for a long time, such as 0 to 50 seconds and 50 to 100 seconds.

FIG. 7 is an exemplary diagram showing the linear velocity and the rotational velocity of the follower robot of FIG. 5;

Referring to FIG. 7, graphs 710, 720, 730, and 740 may show at least one of a linear velocity and a rotational velocity.

The graph 710 is a linear velocity graph of the follower robot 1 540 and the graph 720 is a rotation velocity graph of the follower robot 1 540. The graph 730 is a linear velocity graph of the follower robot 2 550 and the graph 740 is a rotation velocity graph of the follower robot 2 550.

The follower robot 1 540 and the follower robot 2 550 move at a high speed due to the initial position error in the early stage and converge to the speed of the leading robot 510. In the graph 710 and the graph 730, the follower robot 1 540 and the follower robot 2 550 move at the same speed as the leading robot 510 at the time of linear movement.

The follower robot 1 540 and the follower robot 2 550 move the follower robot 1 540 and the follower robot 2 5 540 in order to keep the leader robot 510 and the leader robot 510 in a large- The speed decreases or increases depending on the position of the motor 550. In particular, it can be seen that the graph 720 and the graph 740 show a large rotational speed due to a sudden turn in the start and 50 seconds interval.

축이 (+)이면 좌회전 속도 및 (-)이면 우회전 속도를 의미한다.
For reference, graph 720 and graph 740

If the axis is (+), it indicates the left rotation speed and (-) indicates the right rotation speed.

8 is a diagram illustrating a simulation of R pattern movement according to an embodiment of the present invention.

Referring to FIG. 8, large-scale control of the follower robot 1 840 and the follower robot 850 when the leading robot 810 moves in the R pattern. Also, the simulation can confirm the large control performance for the target point 1 820 and the target point 2 830 of the follower robot 1 840 and the follower robot 2 850 through the R pattern.

The follower robot 1 840 maintains the target point 1 820 on the left side of the lead robot 810 while the follower robot 2 850 holds the target point 1 820 on the right side of the lead robot 820 And moves to the target point 2 (830). The leading robot 810 has a linear movement (0 to 50 seconds), a rapid 90 ° direction change (50 seconds), a linear movement (50 to 70 seconds), a right rotation (70 to 95 seconds) ) And linear movement (120 to 150 seconds).

를 유지하고, 우회전속도

, 좌회전속도

이다.
At this time, the speed of the leading robot 810 is a linear velocity

And the right turn speed

, Left turn speed

to be.

FIG. 9 is an exemplary view showing an error with respect to the follower robot position and direction in FIG.

축 오차,

축 오차 및 방향

의 오차 중 적어도 하나를 보여줄 수 있다. Referring to FIG. 9, graphs 910, 920, 930, and 940 illustrate

Axis error,

Axial error and direction

The error of at least one of.

The graph 910 is a position error graph of the follower robot 1 840 and the graph 920 is a direction error graph of the follower robot 1 840. Also, the graph 930 is a position error graph of the follower robot 2 850, and the graph 940 is a direction error graph of the follower robot 2 850.

Since the graph 910 and the graph 930 have a difference in the initial positions of the follower robot 1 840 and the follower robot 2 850, a large error occurs but the error decreases with time. 50 seconds of the graph 920 and the graph 940 indicate that the follower robot 1 840 and the follower robot 2 850 have an error caused by a sudden 90 ° change of the leading robot 810, It can be seen that the error is reduced. However, when the follower robot 1 (840) and follower robot 2 (850) continue to maintain the straight line and the rotation movement as in 70 ~ 120 seconds, the direction error caused by the physical factor of the moment of inertia continues.

FIG. 10 is an exemplary view showing an error with respect to the follower robot position and direction in FIG.

10, graphs 1010, 1020, 1030, and 1040 may show at least one of a linear velocity and a rotational velocity.

The graph 1010 is a graph of the linear velocity of the follower robot 1 840 and the graph 1020 is a graph of the rotational velocity of the follower robot 1 840. The graph 1030 is a linear velocity graph of the follower robot 2 850 and the graph 1040 is a graph of the rotation velocity of the follower robot 2 850.

The follower robot 840 and the follower robot 2 850 move at a high speed due to the initial position error and then converge to the speed of the lead robot 810. In the graph 1010 and the graph 1030, the follower robot 1 840 and the follower robot 2 850 move at the same speed as the leading robot 810 at the time of linear movement.

The follower robot 840 and the follower robot 2 850 may be configured such that the speed of the follower robot 810 decreases according to the position of the follower robot 810 in order to maintain a large size with the leading robot 810 when the leading robot 810 suddenly changes direction by 90 ° . Particularly, it can be seen that the follower robot 1 (840) and follower robot 2 (850) have a large rotation speed due to a sudden turn in the start and 50 seconds interval.

축이 (+)이면 좌회전 속도 및 (-)이면 우회전 속도를 의미한다.
For reference, graph 1020 and graph 1040

If the axis is (+), it indicates the left rotation speed and (-) indicates the right rotation speed.

11 is a diagram illustrating an example of a leading robot and a follower robot according to an embodiment of the present invention.

Referring to FIG. 11, the mobile robot used in the experiment was the Adept Pioneer3-DX robot. 11A shows a state in which the landmark 1110 'is installed in the lead robot 1110 and FIG. 11B shows a state in which the web camera 1120' and the sensor 1120 '' are installed in the follower robot 1120 It shows the figure.

) 와 방향(

) 의 정보를 추출하는 목적으로 구성하였다. 또한 추종자 로봇(1120)은 상대 위치 센서(1120'')를 이용하여 선도 로봇(1110)과의 거리를 산출할 수 있다. The follower robot 1120 is further provided with a fixed web camera 1120 'so that the distance of the landmark 1110' provided in the leading robot 1110

) And direction (

) For the purpose of extracting information. Further, the follower robot 1120 can calculate the distance to the leading robot 1110 using the relative position sensor 1120 ".

The leading robot 1110 and the follower robot 1120 can maintain the size by calculating relative distances and angles using the landmark 1110 ', the web camera 1120' and the relative position sensor 1120 ''.

The leading robot 1110 and the follower robot 1120 may be all kinds of mobile robots capable of large-scale control even in an area where communication is impossible, and capable of large-scale control by kinematics and dynamics.

12 is a diagram illustrating an actual implementation of large-scale control of a leading robot and a follower robot according to an embodiment of the present invention.

이다. 또한 추종자 로봇(1220)은 선도 로봇(1210)의 대형을 유지하기 위하여 시작 지점(1230)에서 목표 지점(1240)까지 이동하게 된다. 초기 위치 오차가 있기 때문에 추종자 로봇(1220)은 시작 지점(1230)에서 직선 이동이 아닌 최적의 코스를 선정하여 목표 지점(1140)으로 이동을 한다.
12, the follower robot 1220 realizes large-scale control of the leading robot 1210 in the actual linear movement. The experiment starts with the linear robot 1210 showing a linear movement (0 to 20 seconds). At this time, the speed of the leading robot 1210

to be. Also, the follower robot 1220 moves from the starting point 1230 to the target point 1240 in order to maintain the formation of the leading robot 1210. The follower robot 1220 selects an optimal course, not a linear movement, at the start point 1230 and moves to the target point 1140 because there is an initial position error.

FIG. 13 is an exemplary view showing an error with respect to the follower robot position and direction in FIG.

축 오차,

축 오차 및 방향

의 오차 중 적어도 하나를 보여줄 수 있다. Referring to FIG. 13, graphs 1310 and 1320 illustrate

Axis error,

Axial error and direction

The error of at least one of.

The graph 1310 is a position error graph of the follower robot 1220 and the graph 1320 is a direction error graph of the follower robot 1220. [

It can be seen that the actual implementation results in a gradual decrease in the initial error as in the graph 1310 and the graph 1320. [ However, as the direction error of the follower robot decreases, the graph 1320 vibrates left and right and follows the leading robot 1110. The above result means that there is a difference between the parameter of the dynamic model of the actual mobile robot and the parameter on the controller, and the error of the distance information and the angle information coming from the camera enters through the control input.

FIG. 14 is a flowchart illustrating a process of performing a large control method according to an embodiment of the present invention.

Referring to FIG. 14, a follower robot follows a leading robot and performs a large-scale control.

The camera unit 211 images the image of the leading robot (S110). The camera unit 211 images an image of the leading robot using a camera installed in the follower robot. The leading robot includes a landmark so that the position information can be confirmed.

The first control unit 221 calculates position information of the leading robot (S120). The first control unit 221 can calculate the position information of the leading robot using the image information of the leading robot captured by the camera unit 211. [ Also, the position information of the leading robot may be the reference coordinates.

The first control unit 221 calculates position information of the follower robot (S130). The first control unit 221 can calculate the position information of the follower robot by measuring the distance between the leading robot and the follower robot using the image information of the leading robot captured by the camera unit 211 and the calculated position information of the leading robot have.

The second control unit 222 calculates a target point of the follower robot (S140). The second control unit 222 receives the position information of the leading robot calculated by the first control unit 221, the position information of the follower robot, and the distance and direction of the target point to be maintained by the leading robot and the follower robot stored in the storage unit 240 The target point of the follower robot can be calculated using the angle. The target point is a point at which the leading robot and the follower robot must move in order to maintain their size.

The second control unit 222 may calculate the target point using the back stepping technique which is a nonlinear dynamic system having a recursive structure for stabilized control.

The second controller 222 calculates an error between the current position and the target point of the follower robot (S150). The second control unit 222 can calculate the error between the current position and the target point of the follower robot using the calculated target point. The error may be the distance that the follower robot must move to maintain its formation.

The second controller 222 calculates the linear velocity and the rotation velocity to the target point of the follower robot (S160). The second control unit 222 can calculate the linear velocity and the rotation velocity to the target point of the follower robot using the calculated error. The linear velocities and rotational velocities may be optimal for the follower robot to move to the target point.

The second control unit 222 calculates the torque to the target point of the follower robot (S170). The second control unit 222 can calculate the torque to the target point of the follower robot using the calculated linear velocity and rotation speed. The second control unit 222 calculates the number of torques and makes it possible to move accurately to the target point.

The output unit 230 moves to the target point of the follower robot (S180). The output unit 230 can move the follower robot to the target point using the calculated torque.

15 is a flowchart illustrating a process of performing a large control method according to another embodiment of the present invention.

The sensor unit 212 senses the distance of the leading robot (S210). The sensor unit 212 senses the distance from the lead robot using a sensor installed in the follower robot. The sensor may include at least one of the relative position measurement sensors.

The first control unit 221 calculates position information of the leading robot (S220). The first control unit 221 can calculate the position information of the leading robot using the sensed distance information from the sensor unit 212. Also, the position information of the leading robot may be the reference coordinates.

The first control unit 221 calculates position information of the follower robot (S230). The first control unit 221 can calculate the position information of the follower robot using the distance information sensed by the sensor unit 212 and the calculated position information of the leading robot.

The second control unit 222 calculates a target point of the follower robot (S240). The second control unit 222 uses the distance information and the direction angle between the position information of the leading robot calculated by the first control unit 221, the position information of the follower robot, and the target point, which is stored in the storage unit 240, The target point of the follower robot can be calculated. The target point is a point at which the leading robot and the follower robot must move in order to maintain their size.

The second control unit 222 may calculate the target point using the back stepping technique which is a nonlinear dynamic system having a recursive structure for stabilized control. Also, the second controller 222 can calculate the target point using the parameter obtained through the sensor of the predictor robot.

The second control unit 222 calculates an error between the current position and the target point of the follower robot (S250). The second control unit 222 can calculate the error between the current position and the target point of the follower robot using the calculated target point. The error may be the distance that the follower robot must move to maintain its formation.

The second control unit 222 calculates the linear velocity and the rotation velocity to the target point of the follower robot (S260). The second control unit 222 can calculate the linear velocity and the rotation velocity to the target point of the follower robot using the calculated error. The linear velocities and rotational velocities may be optimal for the follower robot to move to the target point.

The second control unit 222 calculates the torque to the target point of the follower robot (S270). The second control unit 222 can calculate the torque to the target point of the follower robot using the calculated linear velocity and rotation speed. The second control unit 222 calculates the number of torques and makes it possible to move accurately to the target point.

The output unit 230 moves to the target point of the follower robot (S280). The output unit 230 can move the follower robot to the target point using the calculated torque.

The present invention can also be embodied as computer-readable codes on a computer-readable recording medium. A computer-readable recording medium includes all kinds of recording apparatuses in which data that can be read by a computer apparatus is stored. Examples of the computer-readable recording medium include a ROM, a RAM, a CD-ROM, a magnetic tape, a floppy disk, an optical data storage device, and the like, and may be implemented in the form of a carrier wave (for example, transmission via the Internet) . The computer-readable recording medium may also be distributed to networked computer devices so that computer readable code can be stored and executed in a distributed manner.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation in the embodiment in which said invention is directed. It will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the scope of the appended claims.

210: input unit 211: camera unit
212: sensor unit 220:
221: first control section 222: second control section
230: output unit 310: leading robot position information calculation unit
320: follower robot position information calculation unit 330:
340: torque control section 430: target point

Claims (10)

An input unit for sensing a position of the leading robot using a camera and a position sensor; And
A first controller for calculating a position coordinate of the leading robot on the basis of the sensed position, setting a position coordinate of the calculated leading robot as a reference coordinate, and calculating a position coordinate of the follower robot based on the reference coordinate, And a second controller for performing large-scale control and torque control of the follower robot using the calculated position coordinates of the leading robot and the follower robot,
Wherein the first control unit includes:
Calculating position coordinates of the leading robot and the follower robot using at least one of an image captured by the camera and a distance sensed by the position sensor,
Wherein the second control unit comprises:
Calculating a target point for maintaining the follower robot in accordance with the movement of the lead robot, calculating an error with respect to the calculated target point and the current position coordinates of the follower robot, and calculating, based on the calculated error, Calculating a linear speed and a rotation speed to a point, calculating a torque based on the calculated linear speed and rotation speed,
The target point,
Wherein the controller is a point at which the follower robot must move to maintain a predetermined size as the leading robot moves and is calculated using parameters measured by the back stepping method or the position sensor. Large control unit.
delete delete delete delete delete The method according to claim 1,
Wherein,
Wherein the torque is calculated using at least one of the mass, inertia, centripetal force, frictional force, and gravity of the follower robot.
Leading robots to lead followers' robots in front of large
And the follower robot moving to a target point for maintaining the predetermined robot and the predetermined size,
The follower robot
An input unit for sensing a position of the leading robot using a camera and a position sensor; And
A first controller for calculating the position coordinates of the leading robot based on the sensed position, setting the position coordinates of the calculated leading robot to the reference coordinates, and calculating the current position coordinates based on the reference coordinates, And a second controller for performing a large control and a torque control using the position coordinates and the current position coordinates of the lead robot,
Wherein the first control unit includes:
Calculates the current robot position and current position coordinates using at least one of an image captured by the camera and a distance sensed by the position sensor,
Wherein the second control unit comprises:
Calculating a target point for maintaining a large size according to the movement of the lead robot, calculating an error between the calculated target point and the current position coordinates, calculating a linear velocity and a rotation speed to the target point based on the calculated error Calculates a torque based on the calculated linear velocity and the rotation speed,
The target point,
Wherein the follower robot is a point at which the follower robot must move for maintaining a predetermined size as the leading robot moves, and is calculated using the back stepping technique or the parameter measured at the position sensor.
9. The method of claim 8,
In the lead robot,
Comprising at least one landmark,
The input section captures an image of the landmark,
Wherein the controller calculates the position information of the leading robot using the image of the captured landmark.
A first step of detecting the position of the leading robot using a camera and a position sensor installed in the follower robot;
Calculating the position coordinates of the leading robot based on the detected position of the leading robot, setting the position coordinates of the calculated leading robot as reference coordinates, and calculating the position coordinates of the follower robot based on the reference coordinates A second step;
A third step of calculating a target point of the follower robot based on the calculated position coordinates of the leading robot and the follower robot and calculating an error with respect to the calculated target point and the current position coordinates of the follower robot;
Calculates a linear velocity and a rotation speed necessary for the follower robot to move to a target point on the basis of the calculated error, and calculates a torque that the follower robot moves to a target point on the basis of the calculated linear velocity and rotation speed Step 4; And
And a fifth step in which the follower robot moves to a target point on the basis of the calculated torque,
The second step comprises:
Calculating position coordinates of the leading robot and the follower robot using at least one of an image captured by the camera and a distance sensed by the position sensor,
In the third step,
Wherein the target point is calculated using a back stepping method or a parameter measured by the position sensor.

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