KR101234799B1 - Method and apparatus for controlling movement of robot - Google Patents

Abstract

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

According to an embodiment of the present invention, a method of controlling a mobile robot may include generating an image frame at predetermined intervals while rotating the mobile robot in a stationary state when a movement command is received, detecting a pointer using the generated image frame; And moving the mobile robot to a position of the detected pointer.

Mobile robot, remote control

Description

Mobile robot control apparatus and method {Method and apparatus for controlling movement of robot}

1 is a view schematically showing a mobile robot control system according to an embodiment of the present invention.

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

3A is a timing diagram of a control signal for instructing to generate an image frame and a control signal for irradiating the indicator light.

3B is a view showing an image frame photographed by a mobile robot according to an embodiment of the present invention.

4A and 4B are views illustrating a difference frame generation process according to an embodiment of the present invention.

5 illustrates a series of image frames.

6 is a flowchart illustrating a mobile robot control method according to an embodiment of the present invention.

7 is a view for explaining a position and direction detection method through an image frame.

DESCRIPTION OF THE REFERENCE NUMERALS

110: receiving unit 120: driving management unit

130: control unit 140: recording unit

150: image frame processing unit 160: pointer detection unit

The present invention relates to a mobile robot, and more particularly to a control method and apparatus for moving a mobile robot.

In general, robots have been developed for industrial purposes and used as part of factory automation, or have been used to perform tasks on behalf of humans in extreme environments that humans cannot tolerate. This field of robotics has recently been used in the state-of-the-art space development industry and has evolved to the development of human-friendly home robots. In addition, the robot is used in the human body instead of the medical device, and thus is used for the treatment of the minute human biological tissue which was impossible to treat with the conventional medical device. The development of such dazzling robotics has been spotlighted as a cutting-edge field that will newly emerge in place of the information revolution by the Internet and the biotechnology field that is popular.

Among them, the robot for home use is the main role, which is the main role of expanding the existing heavy industry-oriented robotics field into the light industry-oriented robotics field, which has been limited to industrial robots. The cleaning robot is usually composed of a driving means for movement, a cleaning means for cleaning, and a monitoring means for detecting an omnidirectional obstacle.

In general, the drive means is composed of a drive motor for exerting a driving force, a wheel having a track or a predetermined diameter driven by the drive motor, a drive control circuit for controlling the drive and the like. The cleaning means includes a dust collector for collecting and removing dust and the like, and a dust collecting control circuit for controlling the dust collecting behavior. In addition, the monitoring means is composed of a surveillance camera for capturing omnidirectional obstacles, and a transmission device for transmitting an image captured by the surveillance camera to the user.

Such a mobile robot performs assigned tasks while moving by itself, but in some cases, a user directly moves the mobile robot in order to move the mobile robot to a desired position. Therefore, a technique for simply moving a mobile robot to a desired position is required.

It is an object of the present invention to simply move a mobile robot to a location desired by a user.

The objects of the present invention are not limited to the above-mentioned objects, and other objects not mentioned can be clearly understood by those skilled in the art from the following description.

In order to achieve the above object, the method for controlling a mobile robot according to an embodiment of the present invention generates an image frame at predetermined intervals while rotating the mobile robot in a stationary state when a movement command is received, using the generated image frame. Detecting a pointer, and moving the mobile robot to a position of the detected pointer.

In order to achieve the above object, a mobile robot control apparatus according to an embodiment of the present invention, the photographing unit for generating an image frame every predetermined period when a movement command is received, a pointer detector for detecting a pointer in the generated image frame, and And a travel management unit configured to rotate the mobile robot in a stationary state when the movement command is received and to move the mobile robot to a position of the pointer when the pointer is detected.

Specific details of other embodiments are included in the detailed description and the drawings.

Advantages and features of the present invention and methods for achieving them will be apparent with reference to the embodiments described below in detail with the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. To fully disclose the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout.

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

1 is a view schematically showing a mobile robot control system according to an embodiment of the present invention. The illustrated mobile robot control system includes a mobile robot 100 and a remote controller 200.

The remote controller 200 outputs the indicator light 10. The pointing position 30 of the indicator light 10 becomes a pointer indicating the destination of the mobile robot 100. The remote controller 200 may irradiate the indicator light 10 at regular intervals. As the indicator light 10, an IR laser is preferably used. However, the present invention is not limited to the kind of the indicator light 10.

In addition, the remote controller 200 transmits a movement command signal to the mobile robot 100. An RF signal of a predetermined frequency band may be used as the moving signal. The movement command signal may include synchronization information for synchronizing an image photographing time point of the mobile robot 100 with an irradiation time point of the indicator light 10.

The mobile robot 100 may rotate in a driving and stopping state. In addition, the mobile robot has a function of capturing a surrounding image and detecting a pointer through the captured image.

In order to move the mobile robot 100 to a feature position, the user may irradiate the indicator light 10 to a desired point by using the remote controller 200. In order to enable the user to visually sense the pointing position 30 of the indicator light 10, the remote controller 200 may irradiate the visible light 20 together with the indicator light 10. Therefore, the user can adjust the pointing position 30 by checking the irradiation point of the visible light.

The remote controller 200 transmits a movement command signal when the indicator light 10 is irradiated. The mobile robot 100 that receives the movement command signal from the remote controller 200 photographs the images at regular intervals while rotating in the stationary state, and detects the pointer using the photographed images. When the pointer is detected, the mobile robot 100 travels to the position of the pointer.

Hereinafter, an apparatus and method for controlling the mobile robot 100 will be described in more detail.

2 is a block diagram showing a mobile robot control apparatus according to an embodiment of the present invention. The illustrated mobile robot control apparatus includes a receiver 110, a travel manager 120, a controller 130, a photographing unit 140, an image frame processor 150, and a pointer detector 160, and a mobile robot 100. ) May be included.

The receiver 110 receives a movement command signal received from the remote controller 200. According to an embodiment of the present invention, the move command signal may be transmitted through an RF signal. However, the present invention is not limited thereto.

The driving manager 120 controls the movement of the mobile robot 100. To this end, the driving manager 120 includes a plurality of driving wheels (not shown) and a direction control device (not shown), but may include other known driving means as far as possible to move the mobile robot 100. If the receiver 110 receives a movement command from the remote controller, the driving manager 120 controls the mobile robot 120 to rotate in a stopped state.

In addition, the driving manager 120 detects the rotation speed of the driving wheel. Through this, the driving manager 120 may measure the position change and the direction change between the previous position and the current position of the mobile robot 100. For this purpose, the driving manager 120 may include an encoder or a gyroscope.

The photographing unit 140 generates an image frame by photographing a surrounding image of the mobile robot 100. Preferably, the photographing unit 140 may include a ccd (chage-coupled device) camera. However, the present invention is not limited thereto, and the photographing unit 140 may include a known camera capable of capturing the indicator light 10 irradiated by the remote controller 200. In order to increase detection performance of the pointing point 30 of the indicator light 10 irradiated by the remote controller 200 and to reduce noise, the photographing unit 140 filters a predetermined frequency band including the frequency of the indicator light 10. It may include an optical filter.

The photographing unit 140 generates an image frame periodically from the time when the receiving unit 110 receives the movement command signal from the remote controller 200. The first image frame generation time is synchronized through predetermined synchronization information included in the movement command signal, and the image frame generation period of the photographing unit 140 is half of the period in which the remote controller 200 irradiates the indicator light 10. It is preferable. This will be described with reference to FIG. 3A.

3A is a timing diagram of a control signal A instructing the photographing unit 140 to generate an image frame and a control signal B instructing the remote controller 200 to irradiate the indicator light 10. The photographing unit 140 generates an image frame when the control signal A has a high value, and the remote controller 200 indicates the indicator light 10 when the control signal B has a high value. Investigate

In the illustrated timing diagram, it can be seen that the time point t1 at which the photographing unit 140 acquires the first image frame is the same as the time point at which the remote controller 200 irradiates the indicator light 10, which is synchronized through the synchronization information. Is the result. In addition, according to the illustrated timing diagram, it can be seen that the period in which the photographing unit 140 generates the image frame is half of the period in which the remote controller 200 emits the indicator light 10. Accordingly, when the photographing unit 140 looks at the image frame obtained by continuously photographing the pointing point 30 of the indicator light 10, as illustrated in FIG. 3B, the pointer 310 is photographed every odd-numbered image frame. Depending on the synchronization control, a pointer may be photographed every even-numbered image frame.

The image frame processor 150 generates a difference frame between successive image frames provided by the photographing unit 140. Preferably, when there is a phase recognized as a pointer in the image frame provided by the photographing unit 140, the image frame processor 150 temporally among three consecutive image frames including the image frame. A difference frame between adjacent image frames may be generated.

For example, when an image frame in which an image corresponding to a pointer exists is input, the image frame processing unit 150 may have two adjacent image frames 410 and two adjacent front and rear sides of the image frame 410 as shown in FIG. 4A. The difference frames 440 and 450 between the frames 420 and 430 may be generated. In this case, the pointer 460 exists only in the center image frame 410.

As another example, when an image frame in which an image corresponding to a pointer exists is input, the image frame processing unit 150 may input two image frames 520 and 530 which are next to the image frame 510 as shown in FIG. 4B. ) May generate a difference frame 540 between the difference frame 550 between the image frame 550 and the image frame 520 input immediately after the corresponding image frame 540. In this case, among the three image frames 510, 520, and 530, pointers 560a and 560b exist on the first image frame 510 and the third image frame 530.

The difference frame mentioned above may be obtained as an absolute value for the difference between two image frames. In addition, whether or not a phase corresponding to a pointer exists in an image frame may include storing reference information about an image obtained by photographing an actual pointer in advance, and then storing an image having a similarity to the reference information and a threshold or more within the image frame. It can judge by searching.

The pointer detector 160 extracts a template including a phase corresponding to a pointer from two difference frames provided by the image frame processor 150, and performs a template matching operation between the extracted templates. It is determined whether the pointers match each other.

In this case, the pointer detector 160 may predict the degree of rotation between each image frame using the rotational speed of the mobile robot provided from the driving manager 120 and the image frame generation cycle of the photographing unit 140. Even in successive image frames, there is a difference with respect to the photographing area according to the rotational motion of the mobile robot 100, and the degree of rotation between the image frames refers to such a difference. The degree of rotation between image frames may be stored in advance through a preliminary experiment. Accordingly, the pointer detector 160 may set a search area to compare the templates in the image frames according to the degree of rotation between the image frames. This can reduce the error of pointer detection.

The functional blocks constituting the mobile robot control apparatus described above may be implemented as a kind of module. A module refers to software or a hardware component such as a Field Programmable Gate Array (FPGA) or an Application Specific Integrated Circuit (ASIC), where the module plays certain roles. However, a module is not limited to software or hardware. A module may be configured to reside on an addressable storage medium and may be configured to execute one or more processors. Thus, by way of example, a module may include components such as software components, object-oriented software components, class components and task components, and processes, functions, attributes, procedures, Microcode, circuitry, data, databases, data structures, tables, arrays, and variables, as will be appreciated by those skilled in the art. The functionality provided by the components and modules may be combined into a smaller number of components and modules or further separated into additional components and modules.

6 is a flowchart illustrating a mobile robot control method according to an embodiment of the present invention.

First, when the receiver 110 receives a movement command signal from the remote controller 200 (S610), the driving manager 120 controls the mobile robot 100 to rotate at a constant speed (S615). The rotational motion of the mobile robot 100 is continued until a pointer detection success or a pointer detection failure is confirmed, which will be described below.

At the same time, the photographing unit 140 generates an image frame by performing a photographing operation (S620). As described above, the photographing unit 140 uses the synchronization information included in the movement command signal to synchronize the image frame generation time with the irradiation time of the indicator light 10 of the remote controller 200. In addition, the photographing unit 140 generates an image frame at a predetermined period, and the generation period of the image frame is half of the irradiation period of the indicator light 10 of the remote controller 200.

Thereafter, the controller 130 determines whether a pre-extracted template exists (S625). If the template does not exist, the image frame processing unit 150 determines whether a phase corresponding to the pointer exists in the consecutive image frames provided by the photographing unit 140 (S630).

If there is an image corresponding to the pointer, the image frame processor 150 generates a difference frame between temporally adjacent image frames among three consecutive image frames including the frame (S635).

In this case, each image frame is obtained as a result of photographing a slightly different scene by the rotation of the mobile robot 100. Therefore, according to an exemplary embodiment of the present invention, the image frame processor 150 may obtain a difference value for the same region between image frames in consideration of the degree of rotation of the mobile robot 100.

The pointer detector 160 extracts a template including an image corresponding to a pointer from the difference frame generated by the image frame processor 150 (S640), and performs a template matching operation (S645). Since the template matching operation may use a known technique, the detailed description thereof will be omitted. If the two templates match, the pointer detector 160 may determine that the actual pointer exists in the image frame.

On the other hand, if the extracted template is present as a result of the determination in step S625, the pointer detector 160 performs a template matching operation using the extracted template (S645). As a result, if an area matching the template exists in the image frame, the pointer detector 160 may determine the corresponding area as a pointer existence area.

If a pointer is detected in the image frame as a result of the template matching operation (S650). The controller 130 determines whether the number of pointer detections is greater than a predetermined threshold number of times (S655). If the number of times of detecting the pointer is greater than the threshold number of times, the driving manager 120 drives the mobile robot to the position where the pointer is detected (S660).

The position at which the pointer is detected may be obtained through the coordinates of the pointer in the image frame. For example, the image previously photographed by the mobile robot is divided into predetermined blocks as shown in FIG. 7, and pre-experimental information on how far the direction and the direction of the area corresponding to each block has from the actual mobile robot is shown. Can be stored through. In this case, the mobile robot 100 may obtain distance and direction information corresponding to the block where the pointer is located in the image frame. In addition, various known techniques for moving a mobile robot to a specific point on an image frame may be applied.

Referring back to FIG. 6, if the number of detection of the pointer is not greater than the threshold number of times in step S655, the controller 130 controls each component of the mobile robot 100 to repeat the above process from step S620.

On the other hand, if the pointer is not detected in step S645, the controller 130 determines whether the rotation angle of the mobile robot 100 is smaller than the threshold angle (S665). The rotation angle of the mobile robot 100 may be obtained through the driving manager 120. If the rotation angle of the mobile robot 100 is smaller than the threshold angle, the controller 130 controls each component of the mobile robot 100 to repeat the above-described process from step S620.

However, if the rotation angle of the mobile robot 100 is greater than or equal to the threshold angle, the controller 130 notifies the user that the pointer detection has failed (S670).

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It will be understood. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive.

According to the mobile robot control method and apparatus of the present invention as described above has the effect that the user can easily move the mobile robot to a desired position.

Claims (10)

Generating an image frame every predetermined period while rotating the mobile robot in a stationary state when a movement command is received; Detecting a pointer through comparison between adjacent frames in time among the generated image frames; And Moving the mobile robot to a position of the detected pointer. The method of claim 1, Generating the image frame, Synchronizing a photographing time point using a synchronization signal included in the movement command; And And photographing an image for each period from the photographing time point. The method of claim 1, The pointer is a pointing position of the indicator light irradiated by a predetermined remote controller, The generation period of the image frame is half the irradiation period of the indicator light, mobile robot control method. The method of claim 1, The detecting step, Generating a difference frame between temporally adjacent image frames among three consecutive image frames including the image frame when an image corresponding to predetermined reference information exists in the image frame; Extracting a template including the image from the difference frame; And And performing a matching operation with respect to the template. The method of claim 1, Moving the mobile robot, Moving the mobile robot to a position of the detected pointer when the pointer is detected more than a threshold number of times. A photographing unit generating an image frame at a predetermined cycle when a movement command is received; A pointer detector which detects a pointer through a comparison between temporally adjacent frames among the generated image frames; And And a travel management unit configured to rotate the mobile robot in a stopped state when the movement command is received and to move the mobile robot to a position of the pointer when the pointer is detected. The method according to claim 6, The photographing unit synchronizes a photographing time point using a synchronization signal included in the movement command, and photographs an image every cycle from the photographing time point. The method according to claim 6, The pointer is a pointing position of the indicator light irradiated by a predetermined remote controller, And a generation period of the image frame is half of an irradiation period of the indicator light. The method according to claim 6, If there is an image corresponding to the predetermined reference information in the image frame, further comprising an image frame processing unit for generating a difference frame between adjacent video frames in time from among three consecutive image frames including the image frame, The pointer detector extracts a template including the image from the difference frame and performs a matching operation on the template. The method according to claim 6, And the traveling management unit moves the mobile robot to the position of the detected pointer when the pointer is detected more than a threshold number of times.

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