KR20200030476A - Straight device in mobile robot and thereof method - Google Patents

Abstract

The present invention relates to a device for maintaining straightness in a moving robot, capable of allowing the moving robot to perform work in a field while maintaining the straightness, and a method thereof. According to the present invention, the device comprises: a photographing unit having a light source installed on the longitudinal extension line of a first bank and photographing a driving direction side of the moving robot moving on the first bank when the light source emits a first visible light in the longitudinal direction of the first bank; a tracking unit checking the position of a straight guideline (hereinafter, referred to as a current guideline) formed by the first light in an image photographed in the photographing unit and checking an error value between the position of the current guideline and the position of a previously stored reference guideline; a posture detection unit detecting a posture change of the moving robot moving on the first bank to generate a detected posture change value; a posture maintenance unit performing a posture maintenance operation corresponding to the posture change value and using the position error value or using the position error value and the posture change value to generate a steering control signal allowing the moving robot to continuously and straightly move in an initial advancing direction; and a steering unit controlling steering of the steering wheel in accordance with the steering control signal of the posture maintenance unit.

Description

A device for maintaining the straightness of a mobile robot and its method {Straight device in mobile robot and its method}

The present invention relates to a mobile robot that performs work by autonomous driving in a road environment, and relates to a straightness maintenance device and method for the mobile robot.

Of the mobile robots performing farming work in the open field environment, the mobile robots performing autonomous driving must maintain straightness in order to perform certain tasks in a predetermined work area.

If the straightness is not maintained, it is out of a predetermined work area or a planned work cannot be performed.

Therefore, there is a need for a technology that guarantees straightness for a mobile robot that performs work by autonomous driving in a road environment.

The problem to be solved by the present invention is to provide a mobile robot straightness maintenance device and a method thereof, which enables a mobile robot to work while maintaining a straight line in a working area of a road environment.

In addition to the above problems, embodiments according to the present invention may be used to achieve other problems not specifically mentioned.

In order to solve the above-described problem, the linearity maintaining device of the mobile robot according to an embodiment of the present invention is provided with a light source installed on a longitudinal extension line of the first dug, and the light source can be visually identified in the longitudinal direction of the first dug. 1 In the state of irradiating light, the photographing unit photographing the driving direction side of the mobile robot moving the first head image, the guideline of the straight line formed by the first light in the image photographed by the photographing unit (hereinafter " Tracking unit that detects the position of the current guideline and the error value between the position of the current guideline and the position of the pre-stored reference guideline, and detects a change in the attitude of the mobile robot moving the first bank. And a posture detecting unit generating a sensed posture change value, performing a posture maintenance operation corresponding to the posture change value, and the position error value or the position error value and phase It may include a posture maintaining unit for generating a steering control signal for the mobile robot to continue to move in the initial progress direction using a posture change value, and a steering unit for controlling the steering of the steering wheel according to the steering control signal of the posture maintaining unit have.

When the posture maintaining unit receives the posture change value from the posture detecting unit, it compensates for the displacement of the body of the mobile robot by performing an operation corresponding to the posture change value, and analyzes the position error value received from the tracking unit to initiate the mobile robot. It is possible to output a steering control signal to keep going straight in the direction of travel.

When the posture maintaining unit receives the posture change value from the posture detecting unit, it compensates for the displacement of the body of the mobile robot by performing an operation corresponding to the posture change value, and processes the position error value received from the tracking unit as invalid information. can do.

The method for maintaining the straightness of the mobile robot according to an embodiment of the present invention for solving the above problems is visually identifiable and at least one light source irradiating the first light going straight is installed for the first dud, and the length of the dud Positioning on the extension line, the mobile robot standing at the initial working position on the first bank and photographing the front, the position of the reference guideline based on the position of the guideline of the straight line formed by the first light in the captured image Step of setting to, taking the omni-directional in accordance with the movement of the mobile robot, and grasping the position of the guideline (hereinafter referred to as "current guideline") of the straight line formed by the first light in the captured image, Generating an error value between the position of the current guideline and the reference position, detecting a change in attitude of the mobile robot according to the movement of the mobile robot, Generating a posture change value for the detected posture change, performing a posture maintenance operation corresponding to the posture change value, and using the position error value or the position error value and the posture change value to move the robot And outputting a steering control signal to keep going straight in the initial progress direction to maintain the straightness of the mobile robot.

According to an embodiment of the present invention, the mobile robot moves straight ahead based on the guideline of the laser light that can be visually identified, so that the autonomous mobile robot can perform a desired operation.

1 is a view showing a working environment for maintaining the straightness of the mobile robot according to an embodiment of the present invention.
2 is a view showing an example of a mobile robot according to an embodiment of the present invention.
3 is a block diagram of a straightness maintaining device according to an embodiment of the present invention.
4 is a view showing the error of the guideline grasped through the image taken by the imaging unit according to an embodiment of the present invention.
5 is a flowchart of a method for maintaining straightness of a mobile robot according to an embodiment of the present invention.
6 is a flowchart of a method for maintaining straightness of a mobile robot according to a second embodiment of the present invention.

 Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art to which the present invention pertains may easily practice. The present invention can be implemented in many different forms and is not limited to the embodiments described herein. In the drawings, parts not related to the description are omitted in order to clearly describe the present invention, and the same reference numerals are used for the same or similar elements throughout the specification. In addition, in the case of a well-known technology, a detailed description thereof is omitted.

In the present specification, when a part “includes” a certain component, it means that the component may further include other components, not to exclude other components, unless otherwise stated.

Hereinafter, an apparatus for maintaining straightness of a mobile robot and a method thereof will be described with reference to the accompanying drawings.

1 is a view showing a working environment for maintaining the straightness of the mobile robot according to an embodiment of the present invention. In FIG. 1, a mobile robot performing field farming is taken as an example.

Referring to Figure 1, the mobile robot 10 is located on the bank of the field. Specifically, the two wheels installed on one side of the mobile robot 10 are located in one goal, and the two wheels installed on the other side of the mobile robot 10 are located in the other goal. Accordingly, the main body of the mobile robot 10 is located on one dud.

The light source 200 is a device that can be identified with the naked eye and irradiates straight light, such as laser light. At least one light source 200 is installed for one dud, and is located on a longitudinal extension line of the dud. That is, the light source 200 is located outside of the ridge.

It is preferable that the light source 200 is installed to be aligned with the center portion in the longitudinal direction of the ridge, but it is not necessary. It is preferable that the light source 200 is positioned at a lower position (based on height) than the photographing unit installed in the mobile robot 10.

The light source 200 is fixed by the fixing means (b). The fixing means (b) may be an object or a person. In the case of a person, the operator (b) stands by holding the light source 200, and in the case of an object, the light source 200 is installed on a fixedly installed fixture (b).

Therefore, the mobile robot 10 photographs the front using the photographing unit when moving the dud (a1, a2, a3), and grasps a straight line (hereinafter referred to as a “guideline”) of light irradiated from the light source 200 in the captured image. To follow the guidelines and go straight.

2 is a view showing an example of a mobile robot according to an embodiment of the present invention. 2, the mobile robot according to an embodiment of the present invention is an agricultural robot for autonomous driving with four wheels. Here, the wheels of the mobile robot may be provided on one side on each side instead of four, that is, two wheels. Of course, the mobile robot according to the embodiment of the present invention may be an autonomous driving robot having various forms.

3 is a block diagram of a straightness maintaining device according to an embodiment of the present invention. Referring to FIG. 3, the straightness maintaining device 100 according to an embodiment of the present invention includes a photographing unit 110, a tracking unit 120, a posture detecting unit 130, a posture maintaining unit 140, and a steering unit 150 ).

The photographing unit 110 is installed on the body (not shown) of the mobile robot 10 and provides a tracking unit 120 with an image photographed by photographing a driving direction side of the mobile robot 10. Here, the body is a part installed between the wheels of the opposing mobile robot 10. The photographing unit 110 is installed to be positioned above the irradiated light so as to be able to photograph the light irradiated from the light source 200 (hereinafter referred to as “laser light”). Preferably, since the laser light is irradiated downwardly of the imaging unit 110, the imaging unit 110 is tilted downward to perform imaging.

The tracking unit 120 analyzes the image taken by the photographing unit 110 to identify the laser beam of the straight line irradiated from the light source 200, that is, the laser light guideline, and grasps the position of the guideline in the image. The tracking unit 120 sets the laser light guideline identified from the image taken by the photographing unit 110 as a reference guideline at a work start point (ie, the initial position of the mobile robot) in the corresponding bank. Accordingly, the tracking unit 120 compares the laser light guideline obtained from the image taken while the mobile robot 10 moves, that is, the current guideline with the reference guideline, and whether a position error occurs and an error value when the position error occurs (a degree of position error) ).

The position error for the laser light guideline will be described with reference to FIG. 4. 4 is a view showing the error of the guideline grasped through the image captured in the in accordance with an embodiment of the present invention.

Referring to FIG. 4, the entire screen A is a video screen photographed by the photographing unit 110. On the image screen A, the working head (a1 or a2 or a3) is photographed, and the laser light guideline is photographed. In the case where the laser beam guideline is located at the center of the screen at the starting point of the operation of the mobile robot 10, a straight line located at the center of the screen becomes the reference guideline L1 as shown in FIG.

If the current guide line L2 is located on the left side of the center of the screen, such as the laser light guide line L2 in the captured image, the tracking unit 120 determines that a position error has occurred, and the laser light guide line ( Pixel spacing between L2) and the reference guideline L1 (the x-axis and y-axis spacing on the screen is grasped and the pixel spacing is provided to the posture maintaining unit 140 as a position error value e1.

At this time, the position error value e1 is a distance (distance difference) from the current guideline L2 compared to the reference guideline L1, and also the current guideline L2 relative to the reference guideline L1. It can be seen how much the difference angle between the direction and the reference guide line L1 is. Here, the distance difference represents the moving distance of the mobile robot 10 to which the mobile robot 10 should return to the reference guide line L1, and the direction of the current guide line is the mobile robot 10 to return to the reference guide line L1. ), It is possible to grasp the steering direction (eg, left or right), and the difference angle indicates the steering degree of the mobile robot 10 to return to the reference guideline L1.

Meanwhile, the tracking unit 120 may generate a separate error value corresponding to the pixel spacing in addition to the pixel spacing and provide it to the posture maintaining unit 140.

As another example, in the photographed image, when the laser light guide line L3 is located in the center of the screen to the right, the tracking unit 120 determines that a position error has occurred, and the laser light guide line L3 and the reference guideline ( L1) the pixel spacing (x-axis and y-axis spacing on the screen) is determined and the pixel spacing is provided to the posture maintaining unit 140 as a position error value e2.

The posture detecting unit 130 detects a posture change of the mobile robot 10, that is, the degree to which the body of the mobile robot 10 is twisted up, down, left, and right, and generates a posture change value corresponding to the detected posture change It is provided to the posture holding unit 140. The posture detecting unit 130 may be configured of a gyro sensor, an IMU (Initial Measurement Unit), or any other sensor capable of detecting posture change.

The posture maintaining unit 140 compensates for the distortion of the body of the mobile robot 10 by performing an operation corresponding to the posture change value when the posture change value is received from the posture detection unit 130. In addition, the posture maintaining unit 140 analyzes the position error value received from the tracking unit 120 and performs posture control to continuously move the mobile robot 10 in the initial progress direction.

On the other hand, when the posture maintaining unit 140 receives the posture change value from the posture detecting unit 130, it determines the position error value received from the tracking unit 120 as invalid information, and posture from the posture detecting unit 130. When the change value is not received, the position error value received from the tracking unit 120 may be determined as valid information and posture control corresponding to the position error value may be performed. For this reason, that the attitude change value is generated means that the body of the mobile robot 10 is twisted, which means that the photographing unit 110 installed in the body is photographed in the wrong state. That is, when the posture change value is generated, the image photographed by the photographing unit 110 causes a position error value to be generated even if the mobile robot 10 proceeds in the initial progression direction.

On the other hand, when receiving the posture change value from the posture detecting unit 130, the posture maintaining unit 140 may stop the operation of the tracking unit 120 until the operation corresponding to the posture change value is completed.

The steering unit 150 operates under the control of the posture maintaining unit 140 to adjust the traveling direction of the mobile robot 10.

5 is a flowchart of a method for maintaining straightness of a mobile robot according to a first embodiment of the present invention. Referring to FIG. 5, in order to work on the weir (a1) using the mobile robot 10, first, the mobile robot 10 is positioned at the initial working position of the weir (a1) (S501). It is a position opposite to the light source 200 of the ridge (a1).

When the mobile robot 10 is written at the initial working position on the bank, the light source 200 irradiates laser light onto the bank, and the photographing unit 110 of the mobile robot 10 photographs the front (S502). The image photographed by the photographing unit 110 is analyzed by the tracking unit 120. The tracking unit 120 identifies a linear laser light guideline in the captured image, and the position in the image of the laser light guideline (linear The location) is determined (calculated) (S503). Then, the tracking unit 120 sets the identified laser light guideline as a reference guideline and sets the position in the image of the reference guideline as the reference position (S504).

When the setting of the reference position is completed, the mobile robot 10 moves linearly toward the light source 200, and at the same time, the photographing unit 110 photographs the front (S505).

When the mobile robot 10 moves, the tracking unit 120 receives the image captured by the imaging unit 110 and grasps the position of the laser light guideline in the captured image (S506). Then, the tracking unit 120 compares the identified position of the laser light guideline with the reference position to determine whether the position of the laser light guideline matches the reference position (S507).

In the process of determining S507, the tracking unit 120 generates a position error value between the position of the laser light guideline and the reference position when the position of the laser light guideline and the reference position do not match, and maintains the position error value in the posture maintaining unit 140 ) (S508).

In addition, when the mobile robot 10 is moved, the posture detecting unit 130 detects a posture change of the mobile robot 10, that is, a distortion of the body (S509), and generates a posture change value for the detected posture change. Provided to the holding unit 140 (S510). On the other hand, the posture detecting unit 130 is configured to cause the mobile robot 10 to progress in a straight direction and not provide a posture change value or inform a value indicating that there is no posture change if there are no changes in the x-axis, y-axis, and z-axis. You can.

The posture maintaining unit 140 compensates for the displacement of the body by performing a posture maintenance control operation corresponding to the posture change value received from the posture detection unit 130, and corresponds to a position error value received from the tracking unit 120. The steering control signal is provided to the steering unit 150 so that the steering unit 150 steers the steering wheel according to the steering control signal so that the traveling direction of the mobile robot 10 becomes the initial advance direction (S511).

6 is a flowchart of a method for maintaining straightness of a mobile robot according to a second embodiment of the present invention. Prior to the description, the method for maintaining the straightness of the mobile robot according to the second embodiment of the present invention is the same as steps S501 to S504 in the method for maintaining the straightness of the mobile robot according to the first embodiment of the present invention, so the description is omitted.

Referring to FIG. 6, the mobile robot 10 linearly moves toward the light source 200, and at the same time, the photographing unit 110 photographs the front (S601).

When the mobile robot 10 moves, the posture detecting unit 130 detects a posture change of the mobile robot 10, that is, a twist of the body (S602), and when the posture change is detected, the posture change value for the detected posture change Is generated and provided to the posture maintaining unit 140 (S603). On the other hand, the posture detecting unit 130 does not provide a posture change value or there is no posture change if there is no change in the x-axis, y-axis, or z-axis as the mobile robot 10 moves in a straight direction. You can let them know.

In addition to the operation of the posture detecting unit 130, the tracking unit 120 receives the image captured by the photographing unit 110, grasps the position of the laser light guideline in the captured image, and determines the position of the captured laser light guideline. The reference position is compared, and through this, it is detected whether a position error in which the position of the laser light guideline and the reference position do not match occur (S605).

Through this detection, if the position of the laser light guideline and the reference position do not match, the tracking unit 120 generates a position error value between the position of the laser light guideline and the reference position and sends the position error value to the posture maintaining unit 140. Provide (S606).

The posture holding unit 140 performs a posture maintenance control operation corresponding to a posture change value received from the posture detection unit 130 to perform an operation for compensating for the distortion of the body. However, the posture maintaining unit 140 does not perform an operation corresponding to the position error value by determining the position error value received from the tracking unit 120 as invalid information because a posture change with respect to the body has occurred (S607).

On the other hand, if the tracking unit 120 generates a position error value in a state in which there is no change in the posture of the body and provides it to the posture maintaining unit 140 (S608), the posture maintaining unit 140 controls steering corresponding to the position error value. The signal is generated and provided to the steering unit 150 (S609), and the steering unit 150 steers the steering wheel according to the received steering control signal so that the traveling direction of the mobile robot 10 becomes the initial advance direction ( S611).

According to another embodiment of the present invention, the posture maintaining unit 140 outputs an operation deactivation signal to the tracking unit 120 when the posture change value received from the posture detecting unit 130 is received through the process S604, and the tracking unit ( If 120 is not operated, and the posture change value received from the posture detection unit 130 is not received or the compensation operation corresponding to the posture change value is completed, an operation activation signal may be output to the tracking unit 120. .

In the above, the implementation of the present invention has been described in detail, but the scope of the present invention is not limited to this, and various modifications and improvements made by those skilled in the art to which the present invention pertains also include the rights of the present invention. Belongs to the scope.

10: mobile robot 100: mobile robot straightness maintenance device
200: light source 110: photographing unit
120: tracking unit 130: posture detection unit
140: posture maintaining unit 150: steering unit

Claims (4)

In a state in which a light source is installed on a longitudinal extension line of the first ridge, and the light source irradiates a first light identifiable with the naked eye in the longitudinal direction of the first ridge,
The photographing unit for photographing the driving direction side of the mobile robot moving the first duo image,
The position of the guideline (hereinafter referred to as "current guideline") of a straight line formed by the first light in the image captured by the photographing unit is grasped, and an error between the position of the current guideline and a previously stored reference guideline Tracking unit to grasp the value,
A posture detection unit that detects a posture change of the mobile robot moving the first dug, and generates a sensed posture change value,
A posture for performing a posture maintenance operation corresponding to the posture change value, and generating a steering control signal to continuously move the mobile robot in the initial direction of travel by using the position error value or the position error value and the posture change value Maintenance, and
A steering unit for controlling the steering of the steering wheel according to the steering control signal of the posture maintaining unit,
Mobile robot straightness maintenance device. In claim 1,
When the posture maintaining unit receives the posture change value from the posture detecting unit, it compensates for the displacement of the body of the mobile robot by performing an operation corresponding to the posture change value, and analyzes the position error value received from the tracking unit to initiate the mobile robot A device for maintaining the straightness of a mobile robot that outputs a steering control signal to keep going straight in the direction of travel. In claim 2,
When the posture maintaining unit receives the posture change value from the posture detecting unit, it compensates for the displacement of the body of the mobile robot by performing an operation corresponding to the posture change value, and processes the position error value received from the tracking unit as invalid information. Mobile robot's straightness maintenance device. With at least one light source irradiating the first light that is identifiable by the naked eye and irradiating straight, is installed on the first dud and positioned on the longitudinal extension line of the dud,
The mobile robot standing in the initial working position on the first bank and photographing the front,
Setting a position of a guideline of a straight line formed by the first light as a reference position in the captured image,
Photographing a forward direction according to the movement of the mobile robot, and grasping the position of a straight line guideline (hereinafter referred to as "current guideline") formed by the first light in the captured image,
Generating an error value between the position of the current guideline and the reference position,
Detecting a posture change of the mobile robot according to the movement of the mobile robot, and generating a posture change value for the detected posture change,
Performing a posture maintenance operation corresponding to the posture change value, and
The position error value, or using the position error value and the attitude change value
And maintaining the straightness of the mobile robot by outputting a steering control signal that causes the mobile robot to continue to move in the initial progress direction.

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