KR20170047850A - Cleaning robot and controlling method thereof - Google Patents

Abstract

Disclosed are a cleaning robot, and a method for controlling the same. The present invention comprises: a data obtaining unit measuring a distance from a current position to a measurement target to obtain actual sensor data; a local map obtaining unit canning a periphery of the current position to obtain a local map based on a prestored environment map; and a processor enabling the local map and the actual sensor data to be matched to locate a coordination of the current position on the local map and calculating a main line angle of a line existing on the local map to determine the driving direction based on the current position.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a cleaning robot,

The present invention relates to a cleaning robot and a control method thereof.

The cleaning robot is a device that cleans impurities such as dust from the floor while traveling on an area to be cleaned without user's operation, and carries out a cleaning operation while traveling according to a predetermined driving pattern. In addition, the cleaning robot determines the distances to the obstacles such as furniture, walls, household appliances, etc. installed in the cleaning area through the sensor, and selectively drives the left motor and the right motor to change directions.

In order to perform the cleaning operation smoothly in various cleaning environments, it is important that the cleaning robot accurately grasp its own position.

In addition, when the cleaning robot starts to be cleaned and starts to be cleaned while maintaining the initial position when the cleaning robot is placed at an oblique angle with respect to the wall surface, an inefficient travel path is generated, .

Therefore, there is a need to accurately determine the traveling direction of the cleaning robot so that the cleaning robot can travel in all areas of the cleaning space.

The present invention provides a cleaning robot for determining a traveling direction of a cleaning robot using a map of an environment in which the cleaning robot performs cleaning and a position of the cleaning robot on the environment map, and a control method thereof.

The cleaning robot according to one aspect includes a data acquiring unit for acquiring real sensor data by measuring a distance from a current position to a measurement object; A local map acquiring unit for acquiring a local map by scanning around the current position based on a pre-stored environment map; Calculating a main line segment angle of a line segment existing in the local map by performing matching between the local map and the real sensor data to grasp coordinates of the current position with respect to the local map, And a processor that determines the processor.

In addition, the processor may determine a main line segment angle by classifying a plurality of straight lines existing in the local map by an angle.

In addition, the processor may rotate the traveling direction of the cleaning robot based on the traveling direction determined based on the current position coordinates.

The data acquiring unit may acquire the room sensor data in a state where the cleaning robot is stopped or acquire the room sensor data while the cleaning robot rotates at a predetermined angle in place, It is possible to obtain real sensor data for all directions while rotating 360 degrees.

Also, the local map obtaining unit extracts virtual sensor data by performing a ray casting method on all directions while rotating 360 ° from the virtual sensor data extraction position centered on the current position of the cleaning robot, Local maps can be obtained.

The local map obtaining unit may extract a local map having a predetermined size centered on each of the plurality of local map extraction positions centered on the current position of the cleaning robot from the environment map.

The processor may further include: a position estimator for determining a current position coordinate of the cleaning robot with respect to the local map; A line segment angle calculating unit for calculating a line segment angle of a line segment existing in the local map; And a direction adjusting unit for causing the cleaning robot to rotate the traveling direction according to the main line segment angle at the current position.

Also, the position estimating unit may include a corresponding point obtaining unit that obtains a plurality of corresponding points through data matching between the real sensor data and the local map; A relative position calculation unit for calculating a relative position of the real sensor data with respect to the local map by using the plurality of corresponding points acquired; A similarity calculation unit for calculating a similarity between the plurality of local maps and the real sensor data; And a positioning unit for determining a relative position of the cleaning robot with respect to the local map having the largest degree of similarity as a current position of the cleaning robot with respect to the environment map to grasp the current position coordinates.

The similarity calculation unit may calculate that the degree of similarity increases as the number of data points commonly included in the local map and the actual sensor data increases.

The line segment angle calculating unit may further include: a straight line obtaining unit obtaining a plurality of straight lines from the local map; And a main line segment angle calculating unit for classifying the plurality of straight lines according to angles to determine main line segment angles.

The straight line obtaining unit may obtain the plurality of straight lines in the local map using a Hough Transform.

In addition, the main line segment angle calculating unit may generate the angle histogram by classifying the plurality of straight lines according to the angle, and may determine the main line segment angle in consideration of the distribution of the angle histogram.

The main line segment angle calculating unit may generate the angle histogram by merging orthogonal or parallel straight lines.

Also, the main line segment angle calculating unit may determine a main line segment angle of the local map by removing a noise of the angle histogram using a low-pass filter.

The cleaning robot may further include a display for outputting a message indicating that the running direction of the cleaning robot has been adjusted according to the main line segment angle.

The cleaning robot may further include an acoustic output unit for outputting, in a voice form, that the traveling direction of the cleaning robot is adjusted according to the main line segment angle.

The cleaning robot further includes: a sensor for measuring a distance; The data acquiring unit may acquire real sensor data by measuring a distance from the sensor to the measurement object using the sensor.

A control method for a cleaning robot on one side includes the steps of: acquiring a local map by scanning the vicinity of a current position; Obtaining a real sensor data by measuring a distance from the current position to a measurement object; Determining a current position coordinate of the local map by performing matching between the local map and the real sensor data; Calculating a main line segment angle of a line segment existing in the local map and determining a traveling direction; And adjusting the traveling direction according to the calculated main line angle.

Also, the acquiring of the local map may acquire the local map by scanning the vicinity of the current position based on the pre-stored environment map run by the cleaning robot.

In addition, the environmental map may be a two-dimensional grid map or a three-dimensional grid map.

The acquiring of the local map may further include performing a ray casting technique on all directions while rotating the virtual sensor data extraction position about 360 degrees from the virtual sensor data extraction position centered on the current position of the cleaning robot, Extracts the local map from the environment map, or extracts a local map of a predetermined size centering on each of the plurality of local map extraction locations centered on the current location of the cleaning robot.

The acquiring of the current position coordinates may include acquiring a plurality of corresponding points through data matching between the real sensor data and the local map. Calculating a relative position of the real sensor data with respect to the local map using the obtained plurality of corresponding points; Calculating a degree of similarity between the plurality of local maps and the real sensor data; And determining the current position of the cleaning robot for the local map having the largest degree of similarity as the current position of the cleaning robot for the environment map.

In the calculating of the degree of similarity, it may be determined that the degree of similarity increases as the number of data points commonly included in the local map and the actual sensor data increases.

In addition, the step of determining the running direction may include: obtaining a plurality of straight lines in the local map; And calculating a main line segment angle by classifying the plurality of straight lines according to an angle.

The step of calculating the main line segment angle may include: generating an angle histogram by classifying the plurality of straight lines according to angles; And determining the main line segment angle in consideration of the distribution of the angle histogram.

The step of calculating the main line segment angle may further include merging straight lines parallel or parallel to each other in the angle histogram.

The disclosed invention determines a traveling direction of the cleaning robot by using the environment map on which the cleaning robot performs work and the position of the cleaning robot on the environment map so that a more accurate running direction can be determined, So that the reliability of the cleaning operation can be improved.

FIG. 1 is a view showing the overall configuration of a cleaning robot system according to an embodiment.
FIG. 2 is a view schematically showing the appearance of a cleaning robot according to an embodiment.
3 is a control block diagram illustrating a configuration of a cleaning robot according to an embodiment.
FIG. 4 is a diagram showing an environment map on which a cleaning robot according to an embodiment runs.
FIG. 5 is a view showing a location where virtual sensor data is extracted at a current position of the cleaning robot according to an embodiment.
6 is a diagram showing a method of calculating the virtual sensor data extraction position in FIG.
FIG. 7 is a diagram illustrating an example of a ray casting technique according to an embodiment.
FIG. 8 is a diagram illustrating an example of virtual sensor data extracted using the ray casting technique of FIG.
9 is a view showing a position where a small local map is extracted at a current position of the cleaning robot according to an embodiment.
10 is a diagram showing an example of a small local map extracted using a small local map extraction location.
FIG. 11 is a control block diagram showing the processor of FIG. 3 in detail.
12 is a control block diagram showing the position estimating unit of FIG. 11 in detail.
13 is a view showing an example of room sensor data acquired by a cleaning robot according to an embodiment.
FIG. 14 is a view showing an example of virtual sensor data acquired by a cleaning robot according to an embodiment.
15 is a diagram illustrating a method of calculating a relative position of real sensor data with respect to a local map according to an embodiment.
16 is a view showing a state in which a local map according to an embodiment is inflated.
17 and 18 are views for explaining the fitting state of the local map and the actual sensor data according to the embodiment.
Fig. 19 is a diagram showing in detail the configuration of the line segment angle calculating unit of Fig. 5; Fig.
20 and 21 are angle histograms generated by classifying a straight line obtained in the edge local map according to the angle.
22 and 23 are diagrams for explaining a method for determining the traveling direction of the cleaning robot.
24 is a flowchart for explaining a control method of the cleaning robot according to one embodiment.
FIG. 25 is a flowchart for explaining the current position estimation method of the cleaning robot of FIG. 24 in detail.
Fig. 26 is a flowchart for explaining the segment angle extracting method of Fig. 24 in detail.

BRIEF DESCRIPTION OF THE DRAWINGS The objectives, specific advantages and novel features of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which: FIG. It should be noted that, in the present specification, the reference numerals are added to the constituent elements of the drawings, and the same constituent elements are assigned the same number as much as possible even if they are displayed on different drawings. Further, in the description of the present invention, detailed description of related air technology will be omitted if it is determined that the gist of the present invention may be unnecessarily blurred. In this specification, the terms first, second, etc. are used to distinguish one element from another, and the element is not limited to these terms.

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

FIG. 1 is a view showing the overall configuration of a cleaning robot system according to an embodiment.

Referring to FIG. 1, the cleaning robot system 1 includes a cleaning robot 100 for performing an operation while autonomously moving a predetermined area, a device for remotely controlling the cleaning robot 100 separated from the cleaning robot 100, And a charging station 300 which is separated from the cleaning robot 100 and charges the battery power of the cleaning robot 100.

The cleaning robot 100 is a device that receives a control command of the device 200 and performs an operation corresponding to a control command. The cleaning robot 100 includes a rechargeable battery and an obstacle sensor that can avoid obstacles during traveling, You can work and run autonomously.

In addition, the cleaning robot 100 recognizes its own position without prior knowledge about the surrounding environment through a camera or various sensors, and performs localization and map-building for creating a map from information on the environment, Can be performed.

The device 200 is a remote control device for wirelessly transmitting a control command for controlling the movement of the cleaning robot 100 or performing the operation of the cleaning robot 100. The device 200 may be a mobile phone, A personal digital assistant (PDA), a portable multimedia player (PMP), a laptop computer, a digital broadcasting terminal, a netbook, a tablet, and a navigation.

In addition, the device 200 includes all devices capable of implementing various functions using various application programs, such as a digital camera, a camcorder, etc., in which wired / wireless communication functions are incorporated.

In addition, the device 200 may be a simple remote control. The remote controller can transmit and receive signals to and from the cleaning robot 100 by using an infrared data association (IrDA).

In addition, the device 200 may be implemented as a radio frequency (RF), a wireless fidelity, a Wi-Fi, a Bluetooth, a Zigbee, a near field communication (NFC) UWB) communication with the cleaning robot 100. If the device 200 and the cleaning robot 100 can exchange wireless communication signals, it is possible to use any method Also,

The device 200 includes a power button for turning on and off the power of the cleaning robot 100 and a charge return button for instructing the cleaning robot 100 to return to the charging station 300 for charging the battery A mode button for changing the control mode of the cleaning robot 100, a start and stop button for starting and stopping the operation of the cleaning robot 100, or for starting, canceling and confirming the control command, and a dial .

The charging station 300 is configured to charge the battery of the cleaning robot 100 and includes a guide member (not shown) for guiding the cleaning robot 100 to be docked. A cleaning robot (not shown) A connection terminal (not shown) is provided to charge the power supply unit 130 (see FIG.

FIG. 2 is a view schematically showing the appearance of a cleaning robot according to an embodiment.

2, the cleaning robot 100 includes a main body 110 that forms an outer appearance, a cover 120 that covers an upper portion of the main body 110, and a driving power source And a driving unit 140 for moving the main body 110. The power supply unit 130 includes:

The main body 110 forms an outer appearance of the cleaning robot 100, and supports various components installed therein.

The power supply unit 130 includes a driving unit 140 and a battery electrically connected to each load for driving the main unit 110 to supply driving power. The battery is provided with a rechargeable secondary battery and is charged with electric power from the charging station 300 when the main body 110 completes the operation and is coupled to the charging station 300.

Further, the power source unit 130 receives the charging current from the charging station 300 when the remaining charge amount is insufficient.

In addition, a caster wheel (not shown) may be installed in front of the main body 110 to vary the angle of rotation according to the state of the floor on which the cleaning robot 100 moves. The caster wheel supports the cleaning robot 100 by stabilizing the posture of the cleaning robot 100 and preventing fall of the cleaning robot 100, and is composed of a roller or a caster-shaped wheel.

The driving unit 140 is provided on both sides of the center of the main body 110 so that the main body 110 can move forward, backward, and run in the course of traveling.

The driving unit 140 rotates in the forward or backward direction according to a command from the processor 180 (see FIG. 3) to be described later so that the cleaning robot 100 can move forward, backward, or rotate. For example, the driving unit 140 is rotated in the forward or backward direction so that the cleaning robot 100 travels forward or backward. While the left driving part 140 is being rotated in the reverse direction, the right driving part 140 is rotated in the forward direction so that the cleaning robot 100 rotates in the left direction with respect to the front direction and the right driving part 140 is rotated in the backward direction The left driving unit 140 is rotated in the forward direction to rotate the cleaning robot 100 in the right direction with respect to the front.

3 is a control block diagram illustrating a configuration of a cleaning robot according to an embodiment.

3, the cleaning robot 100 includes a data acquisition unit 151, a local map acquisition unit 153, a memory 160, an input unit 171, a display 173 ), An acoustic output unit 175, and a processor 180.

The data acquisition unit 151 acquires the room sensor data of the space where the cleaning robot 100 is currently located and measures the distance from the current position of the cleaning robot 100 to the measurement object to acquire the room sensor data .

More specifically, the cleaning robot 100 includes a sensor (not shown) for measuring the distance, and measures the distance from the sensor to the measurement target in accordance with the scan of the 2D sensor or the 3D sensor installed in the cleaning robot 100 So that the actual sensor data of the actual environment where the cleaning robot 100 is located is obtained. The sensor may be a 2D sensor or a 3D sensor.

In this case, the 2D sensor can display the distance to the measurement object in (x, y) coordinates with respect to the reference coordinate system of the sensor, and the 3D sensor can display the distance to the measurement object with (x, y, z ) Coordinates. The number of distance data output from the 2D sensor or the 3D sensor may vary depending on the field of view (FoV) and resolution of the sensor.

That is, the data acquisition unit 151 may change the actual sensor data acquisition mode of the cleaning robot 100 according to the field of view (FoV) of the 2D sensor or the 3D sensor. When the field of view of the sensor is sufficiently secured, the cleaning robot 100 acquires the room sensor data in the stopped state. Or acquires room sensor data while rotating at a predetermined angle in place, or acquires room sensor data for all directions while rotating 360 ° in place.

At this time, when the cleaning robot 100 rotates at a predetermined angle and acquires the room sensor data, it is possible to acquire the room sensor data outside the view of the sensor.

The local map acquiring unit 153 may acquire the local map by scanning the vicinity of the current position based on the pre-stored environment map.

More specifically, the local map acquiring unit 153 acquires a local map (local map) around the current position of the cleaning robot 100 using the virtual sensor data extracted based on the environment map stored in the memory 160 Map).

At this time, the environment map in which the cleaning robot operates may be as shown in Fig. It is assumed that an environment map 500 (Map) in which the cleaning robot 100 operates is given in advance. As shown in FIG. 4, the shape of the environment map 500 may be in the form of a two-dimensional grid map or a three-dimensional grid map. The grid map is a map that stochastically expresses the possibility that an object exists in each grid by dividing the surrounding environment of the cleaning robot 100 into a small grid, which is also called a probability grid map.

Hereinafter, the case where the cleaning robot 100 is located in the I region of the environment map 500 will be described as an example.

The disclosed invention proposes three methods utilizing a two-dimensional grid map as an embodiment of local map acquisition. It should be appreciated that this method can be extended to a 3D grid map.

FIG. 5 is a view showing a position where virtual sensor data is extracted at a current position of the cleaning robot according to an embodiment. FIG. 6 is a diagram illustrating a method of calculating a virtual sensor data extraction position in FIG. FIG. 8 is a diagram illustrating an example of virtual sensor data extracted using the ray casting technique of FIG. 7. Referring to FIG.

First, the local map acquisition unit 153 can acquire the local map through the virtual sensor data extraction method.

The local map acquisition unit 153 performs a ray casting technique on all directions while the cleaning robot 100 rotates 360 degrees from the virtual sensor data extraction position centered on the current position to extract virtual sensor data Thereby obtaining a local map.

As shown in FIG. 5, the cleaning robot 100 selects a plurality of virtual sensor data extraction positions X on a map within a predetermined distance around the current position S as a center.

The virtual sensor data extraction position X is orthogonal to the current position S of the cleaning robot 100 and determines the end of the radius R as the extraction position X (see FIG. 6).

In Fig. 6, the four end points of the X character having the length of one side of 2R become the extraction position (X) of the virtual sensor data.

Thereafter, as shown in FIG. 7, a ray casting technique is performed for all 360 ° directions in each virtual sensor data extraction position X, and as shown in FIG. 8, Data is extracted. FIG. 8 shows an example of virtual sensor data extracted at the virtual sensor data extraction position X. FIG.

FIG. 9 is a view showing a position where a small local map is extracted from a current position of the cleaning robot according to an embodiment, and FIG. 10 is a view showing an example of a small local map extracted using a small local map extraction position.

Secondly, the local map acquiring unit 153 extracts a local map of a predetermined size from the environment map 500, centering on each of the plurality of local map extracting positions centered on the current position of the cleaning robot 100 .

At this time, the local map may be divided into a small local map and a large local map, which is wider than the small local map, according to a preset size.

9, the local map acquiring unit 153 acquires a plurality of small local map extraction positions X within a predetermined distance around the current position S of the cleaning robot 100 on a map .

10, the local map obtaining unit 153 determines the width (W) and the length (H) of the small local map based on the maximum sensing distance of the sensor mounted on the cleaning robot 100. The local map is extracted from the environment map by a predetermined size (W x H) centered on each small local map extraction position (X). FIG. 10 shows an example of a small local map extracted at the small local map extraction position (X).

The local map obtaining unit 153 sets the current position S of the cleaning robot 100 as the center of the large local map extraction and the wider the local map than the small local map Extract the area from the environment map.

The processor 180 compares the coordinates of the current position with respect to the local map by performing matching between the local map and the actual sensor data, calculates the main line segment angle of the line segment existing in the local map, and determines the traveling direction based on the current position . At this time, the current position coordinates can be defined as (x, y, [theta]) with respect to the reference coordinate system {W} shown in the environment map shown in Fig. X and y are position coordinates with respect to a reference coordinate system, and? Is a rotation angle.

That is, the processor 180 controls the overall operation of the cleaning robot 100. The processor 180 performs matching between the local map and the sensor data to recognize the relative position of the cleaning robot 100 to the local map, The traveling direction on the relative position of the cleaning robot 100 can be determined.

In addition, the processor 180 may determine a main line segment angle by classifying a plurality of straight lines existing in the local map according to angles.

In addition, the processor 180 may rotate the traveling direction of the cleaning robot 100 in place based on the traveling direction determined based on the current position coordinates.

11, the processor 180 includes a position estimating unit 181 for grasping the current position coordinates of the cleaning robot 100 with respect to the local map, a line segment calculating unit 182 for calculating the main line segment angle of the line segment existing in the local map, The angle calculating unit 183 and the direction adjusting unit 185 may cause the cleaning robot 100 to rotate the traveling direction according to the main line segment angle at the current position.

12 is a control block diagram showing the position estimating unit of FIG. 11 in detail.

12, the position estimating unit 410 may include a corresponding point obtaining unit 411, a relative position calculating unit 413, a similarity calculating unit 415, and a position determining unit 417. [

The corresponding point obtaining unit 411 obtains a plurality of corresponding points through data matching between the real sensor data obtained by the data obtaining unit 151 and the local map obtained by the local map obtaining unit 153. [

FIG. 13 is a view showing an example of room sensor data acquired by a cleaning robot according to an embodiment, and FIG. 14 is a view showing an example of virtual sensor data acquired by a cleaning robot according to an embodiment.

13 and 14, each sensor data is composed of a plurality of data points. For example, if a point P is included in the real sensor data and P1 is in the virtual sensor data, P1 and P2 correspond to each other. In the case of the 2D sensor, the data points constituting the real sensor data are defined as (x, y) for the reference coordinate system of the cleaning robot 100, respectively. The data points constituting the virtual sensor data are defined as (x, y) for the reference coordinate system {W} of the environmental map (see FIG. 4), respectively.

In this way, the corresponding point obtaining unit 411 obtains the data points of the actual sensor data defined by (x, y) with respect to the reference coordinate system of the cleaning robot 100 and (x, y) To obtain a plurality of data points of the virtual sensor data.

In addition, the corresponding point obtaining unit 411 can remove an outlier among the plurality of corresponding points obtained. In this case, an outlier is defined as a data point that is not commonly included in the real sensor data and the virtual sensor data.

The relative position calculation unit 413 calculates the relative position of the real sensor data on the local map, that is, the coordinate transformation parameters (Rotation and Translation) using the plurality of corresponding points acquired by the corresponding point acquisition unit 411 do.

The relative position calculation unit 413 calculates a plurality of corresponding points obtained by removing the outliers as relative positions of the real sensor data for the local map.

At this time, the relative position is a Coordinates Transformation Parameter (Rotation) which fits a plurality of corresponding points belonging to the real sensor data to a plurality of corresponding points corresponding to each of the local maps, And Translation). Since each data point of the local map is defined with respect to the reference coordinate system of the environment map, the coordinate transformation coefficient for fitting the real sensor data represents the relative position of the cleaning robot 100 to the environment map.

Referring to FIG. 15, the {A} coordinate system can be referred to as a reference coordinate system of a local map and the {B} coordinate system can be referred to as a sensor reference coordinate system.

As shown in FIG. 15, when the data points PA forming the local map correspond to the data points PB of the real sensor data, the relationship between them can be expressed by Equation (1).

[Equation 1]

PA = R 占 PB + t

In this case, R and t are coordinate transformation coefficients, R is a rotation matrix, and t is a translation vector.

That is, if the {A} coordinate is rotated according to R and moved by t, it becomes the same as {B} coordinate system. In one disclosed embodiment, R and t are calculated using Least squares method.

The similarity calculation unit 415 calculates the similarity between the plurality of local maps and the real sensor data by using the relative position of the real sensor data with respect to the local map calculated by the relative position calculation unit 413.

The local map shown in FIG. 14 can be regarded as a binary image. Accordingly, the local map is expanded as shown in FIG. 16 using the dilation method of the digital image processing technique, and the similarity is calculated by fitting the seal sensor data to the expanded local map.

As shown in FIG. 17, if the local map and the real sensor data are well fitted, the number of overlaps between the real sensor data and the expanded local map increases, and the degree of similarity becomes high.

At this time, the similarity calculation unit 415 calculates that the degree of similarity increases as the number of data points commonly included in the local map and the real sensor data increases.

On the other hand, as shown in Fig. 18, when the number of data points commonly included in the local map and the actual sensor data is significantly less than that in Fig. 17, or when the coordinate conversion coefficient is calculated in error, The degree of similarity of data becomes low.

The position determination unit 417 uses the similarity calculated by the similarity calculation unit 415 to calculate the relative position of the cleaning robot 100 with respect to the local map having the greatest similarity to the current position of the cleaning robot 100 for the environment map And determines the current position coordinates.

Referring to FIG. 19, the line segment angle calculating unit 430 may include a straight line obtaining unit 431 and a main line segment angle calculating unit 433.

The straight line obtaining unit 431 can obtain a plurality of straight lines from the local map obtained by the local map obtaining unit 153. [ At this time, the straight line obtaining unit 431 can obtain a plurality of straight lines in the local map by using the Hough Transform.

The plurality of straight lines may be a plurality of sets of points forming a straight line in the local map, or a plurality of sets of points forming the local map itself.

More specifically, the straight line obtaining unit 431 obtains a plurality of straight lines for the local map by performing a Hough transform to a plurality of points constituting a plurality of straight lines extracted from the local map to calculate a voting matrix. At this time, the rows and columns of the voting matrix correspond to the angles of the line segments and the distances from the origin of the reference coordinate system, respectively. The plurality of straight lines obtained in accordance with the Hough transform has an angle.

The main line segment angle calculating section 433 can calculate the main line segment angle by classifying a plurality of straight lines according to the angle.

More specifically, the main line segment angle calculating unit 433 can classify a plurality of straight lines according to angles to generate an angle histogram, and determine the main line segment angle in consideration of the distribution of the angle histogram.

For example, in order to determine the running direction of the cleaning robot 100, the distance of the line segment is not required. Therefore, the main line segment angle calculating unit 433 calculates the straight line obtained by the straight line obtaining unit 431, Can be classified and converted into an angle histogram.

Also, the main line segment angle calculating unit 433 can determine the main line segment angle of the local map by removing the noise of the angle histogram by using a low-pass filter.

Referring to FIG. 21, the main line segment angle calculating unit 433 low pass filters the angle histogram and determines the maximum angle of the vote value as the main line segment angle of the local map.

Further, the main line segment angle calculating section 433 can generate an angle histogram by merging orthogonal or parallel straight lines with each other.

More specifically, the main line segment angle calculating section 433 can merge straight lines at different angles according to preset conditions. The main line segment angle calculating section 433 can improve the reliability of the distribution of the main line segment angles by merging straight lines or mutually horizontal straight lines orthogonal to each other.

For example, the main line segment angle calculating section 433 can classify straight lines that are parallel (180) to the same angle, or classify straight lines that are orthogonal (90) to each other at the same angle. In this way, the orthogonal or parallel straight lines are classified into one angle, and the main line segment angle calculating unit 433 can classify all the straight lines into a specific range.

The main line segment angle calculating unit 433 can generate an angle histogram such that the principal line segment angles are between -45 degrees and +45 degrees by merging straight lines that are parallel to each other or orthogonal to each other. Specifically,? L and? L + 90 degrees shown in FIG. 21 are orthogonal to each other. Therefore, the main line segment angle calculating section 433 can move θL + 90 °, which is larger than + 45 °, by 90 ° and classify it with θL.

On the other hand, the main line segment angle calculating section 433 can calculate the angle at which the largest number of straight line components are distributed, as the main line segment angle.

Referring to FIG. 21, the main line segment angle calculating unit 433 calculates the main line segment angle? L in which the largest number of straight line components exist. That is, the main line segment angle calculating unit 433 low-pass-filters the angle histogram and determines an angle at which the vote value is the maximum as the main line segment angle.

The direction adjusting unit 185 may determine the main line segment angle at the current position of the cleaning robot 100 in the traveling direction and rotate the cleaning robot 100 in the determined traveling direction.

22, when the cleaning robot 100 is positioned in the direction of the rotation angle? R with respect to the reference coordinate system {W}, the cleaning robot 100 is moved in the same direction as the main line segment angle? L, .

The memory 160 stores an environment map on which the cleaning robot 100 travels, an operation program for operating the cleaning robot 100, a travel pattern, position information and obstacle information of the cleaning robot 100 acquired in the traveling process, Can be stored.

The memory 160 stores control data for controlling the operation of the cleaning robot 100, reference data to be used during the operation control of the cleaning robot 100, reference data to be used when the cleaning robot 100 performs a predetermined operation User input information such as operation data, setting data input by the device 200 so that the cleaning robot 100 performs a predetermined operation, and the like can be stored.

In addition, the memory 160 may include an inactive memory device such as a ROM, a PROM, an EPRM, a flash memory, Volatile memory such as a random access memory (RAM) or a storage medium such as a hard disk, a card type memory (e.g., SD or XD memory), or an optical disk. However, the memory 160 is not limited thereto, and various storage media that can be considered by the designer can be used.

The input unit 171 can receive various control information for operating the cleaning robot 100 through the user's operation.

The display 173 is a configuration for outputting a message indicating that the running direction of the cleaning robot 100 has been adjusted according to the main line segment angle. At this time, the display 173 can be displayed using an icon or an LED. The display 173 is not limited to notifying completion of adjustment of the traveling direction of the cleaning robot 100, but it is also possible to output the current position detection notification even when the current position is determined.

As described above, in the case of an LCD UI in which an icon or text can be displayed, the display 173 displays the position recognition and running direction adjustment status of the cleaning robot 100 using an icon or text so that the user can easily confirm the position.

In the case of the LED UI, the display 173 displays the driving direction adjustment state of the cleaning robot 100 by using the lighting or blinking and the difference in the duration time so that the user can easily confirm the driving direction adjustment state.

In addition, the display 173 displays the input information of the user and the operation state of the cleaning robot 100 according to the display control signal of the processor 180. The display 173 displays various information received from the cleaning robot 100, And the like can be displayed.

For example, the display 173 displays the time or the time when the direct control command is input, the speed of the cleaning robot 100, and otherwise displays the current time, reservation information, battery remaining amount, Lt; / RTI >

The display 173 may be a liquid crystal display, a thin film transistor-liquid crystal display, an organic light-emitting diode, a flexible display, a three-dimensional display (3D display).

The sound output unit 175 is configured to output, in a voice form, that the traveling direction of the cleaning robot 100 has been adjusted according to the angle of the main line segment. The sound output unit 175 is not limited to notifying completion of the travel direction adjustment of the cleaning robot 100 but may also output a current position detection notification even when the current position is determined.

The sound output unit 175 outputs the operation state of the cleaning robot 100 and the running direction adjustment state of the cleaning robot 100 in an acoustic manner (for example, Beep sound) according to the sound control signal of the processor 180 The speaker may include a speaker.

In addition, the sound output unit 175 may further include a digital-to-analog converter (DAC) for converting the digitized electrical signal into an analog signal, an amplifier for amplifying the analog signal converted by the digital-to-analog converter .

FIG. 24 is a flowchart for explaining a control method of the cleaning robot according to one embodiment, FIG. 25 is a flowchart for explaining the current position estimation method of the cleaning robot of FIG. 24 in detail, Fig. 3 is a flowchart for explaining the extraction method in detail. Fig.

Referring to FIG. 24, the cleaning robot 100 scans around the current position to obtain a local map (S110).

At this time, the cleaning robot 100 can acquire the local map by scanning the vicinity of the current position based on the pre-stored environment map that the cleaning robot 100 runs. The environmental map may be a two-dimensional grid map or a three-dimensional grid map.

The cleaning robot 100 performs a ray casting technique on all directions while rotating 360 degrees at a virtual sensor data extraction position centered on the current position of the cleaning robot 100 to extract virtual sensor data to acquire the local map Or a local map of a predetermined size centered on each of a plurality of local map extraction positions centered on the current position of the cleaning robot 100, from the environment map.

Next, the cleaning robot 100 measures the distance from the current position to the measurement object to acquire the actual sensor data, and performs matching between the local map and the actual sensor data to grasp the current position coordinates of the local map (S 130 ).

Referring to FIG. 24, the cleaning robot 100 may acquire the room sensor data by measuring the distance from the current position to the measurement object (S131).

More specifically, the cleaning robot 100 includes a sensor (not shown) for measuring the distance, and measures the distance from the sensor to the measurement target in accordance with the scan of the 2D sensor or the 3D sensor installed in the cleaning robot 100 So that the actual sensor data of the actual environment where the cleaning robot 100 is located is obtained. The sensor may be a 2D sensor or a 3D sensor.

Next, the cleaning robot 100 can acquire a plurality of corresponding points through data matching between the room sensor data and the local map (S133).

For example, the cleaning robot 100 calculates data points of actual sensor data defined as (x, y) for each reference coordinate system and virtual sensor data (x, y) defined as To obtain a corresponding point corresponding to a plurality of data points.

Next, the cleaning robot 100 can remove an outlier among a plurality of corresponding points (S135).

Next, the cleaning robot 100 can calculate the relative position of the real sensor data with respect to the local map using the obtained corresponding points (S137).

The cleaning robot 100 calculates a relative position of the real sensor data with respect to the local map, that is, Coordinates Transformation Parameters (Rotation and Translation) using a plurality of corresponding points.

Next, the cleaning robot 100 can calculate the similarities between the plurality of local maps and the real sensor data (S139).

At this time, it can be determined that the more the number of data points commonly included in the local map and the actual sensor data, the higher the degree of similarity.

Next, the cleaning robot 100 may determine the current position of the cleaning robot with respect to the local map having the largest similarity as the current position of the cleaning robot with respect to the environment map (S141). At this time, the current position of the cleaning robot may be in the form of the current position coordinates.

Next, the cleaning robot 100 can determine the traveling direction by calculating the main line segment angle of the line segment existing in the local map (S150).

Referring to FIG. 26, the cleaning robot 100 can obtain a plurality of straight lines from the local map (S151, S153).

Next, the cleaning robot 100 can calculate the main line segment angle by classifying a plurality of straight lines according to the angle (S155).

Step S155 may include a step of classifying a plurality of straight lines by angles to generate an angular histogram, and a step of determining a main line segment angle in consideration of the distribution of the angular histogram.

Step S155 may further include the step of merging orthogonal or parallel straight lines in the angle histogram with each other.

Next, the cleaning robot 100 can adjust the traveling direction according to the calculated main line angle (S170).

Next, the cleaning robot 100 may output a message or voice in which the traveling direction of the cleaning robot is adjusted according to the main line segment angle (S190).

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the same is by way of illustration and example only and is not to be construed as limiting the present invention. It is obvious that the modification or improvement is possible.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

100: Cleaning robot 151: Data acquisition unit
153: Local map acquisition unit 160: Memory
171: input unit 173: display
175: Acoustic output unit 180: Processor
181, 410: Position estimating unit 183: Line segment angle calculating unit
185: direction adjusting unit 411: corresponding point obtaining unit
413: Relative position calculating section 415: Relative position calculating section
417: Positioning section 430: Line segment angle calculating section
431: straight line obtaining unit 433: main line segment angle calculating unit

Claims (26)

A data acquiring unit for acquiring real sensor data by measuring a distance from a current position to a measurement object;
A local map acquiring unit for acquiring a local map by scanning around the current position based on a pre-stored environment map; And
Calculating a main line segment angle of a line segment existing in the local map by performing a matching between the local map and the actual sensor data to grasp the coordinates of the current position with respect to the local map, A processor for determining;
Cleaning robot.
The method according to claim 1,
The processor comprising:
And the main line segment angle is determined by classifying a plurality of straight lines existing in the local map by an angle.
The method according to claim 1,
The processor comprising:
And rotates the traveling direction of the cleaning robot in place based on the traveling direction determined based on the current position coordinates.
The method according to claim 1,
Wherein the data obtaining unit comprises:
Or the cleaning robot obtains the room sensor data while rotating the cleaning robot at a predetermined angle in place or the cleaning robot rotates 360 ° in place to obtain the room sensor data in all directions A cleaning robot that acquires sensor data of a room sensor.
The method according to claim 1,
The local map obtaining unit obtains,
Wherein the robot is rotated 360 degrees at a virtual sensor data extraction position centered on a current position of the cleaning robot to perform a ray casting technique for all directions to extract virtual sensor data to acquire the local map.
The method according to claim 1,
The local map obtaining unit obtains,
And extracts, from the environment map, a local map of a predetermined size centered on each of the plurality of local map extraction positions centered on the current position of the cleaning robot.
The method according to claim 1,
The processor comprising:
A position estimating unit for determining a current position coordinate of the cleaning robot with respect to the local map;
A line segment angle calculating unit for calculating a line segment angle of a line segment existing in the local map; And
A direction adjusting unit for causing the cleaning robot to rotate in a traveling direction according to the main line segment angle at a current position;
Cleaning robot.
8. The method of claim 7,
The position estimating unit may calculate,
A corresponding point obtaining unit for obtaining a plurality of corresponding points through data matching between the real sensor data and the local map;
A relative position calculation unit for calculating a relative position of the real sensor data with respect to the local map by using the plurality of corresponding points acquired;
A similarity calculation unit for calculating a similarity between the plurality of local maps and the real sensor data; And
A positioning unit for determining a relative position of the cleaning robot with respect to the local map having the largest degree of similarity as a current position of the cleaning robot with respect to the environment map to grasp the current position coordinates;
Cleaning robot.
9. The method of claim 8,
Wherein the similarity-
And calculates the degree of similarity as the number of data points commonly included in the local map and the room sensor data increases.
8. The method of claim 7,
The line segment angle calculating unit calculates,
A straight line obtaining unit obtaining a plurality of straight lines from the local map; And
A main line segment angle calculating unit for classifying the plurality of straight lines by an angle to determine a main line segment angle;
Cleaning robot.
11. The method of claim 10,
The straight-
And acquires the plurality of straight lines in the local map using a Hough Transform.
11. The method of claim 10,
The main line segment angle calculating unit calculates,
Wherein the main line segment angle is determined in consideration of the distribution of the angle histogram by generating an angle histogram by classifying the plurality of straight lines by an angle.
13. The method of claim 12,
The main line segment angle calculating unit calculates,
Wherein the angle histogram is generated by merging orthogonal or parallel straight lines.
11. The method of claim 10,
The main line segment angle calculating unit calculates,
And removing the noise of the angle histogram by using a low pass filter to determine the main line segment angle of the local map.
The method according to claim 1,
A display for outputting a message indicating that the running direction of the cleaning robot has been adjusted according to the main line segment angle;
And a cleaning robot.
The method according to claim 1,
An acoustic output unit for outputting, in a voice form, that the running direction of the cleaning robot is adjusted according to the main line segment angle;
And a cleaning robot.
The method according to claim 1,
A sensor for measuring the distance; Further comprising:
Wherein the data acquiring unit acquires the actual sensor data by measuring a distance from the sensor to the measurement target using the sensor.
Scanning the vicinity of the current position to obtain a local map;
Obtaining a real sensor data by measuring a distance from the current position to a measurement object;
Determining a current position coordinate of the local map by performing matching between the local map and the real sensor data;
Calculating a main line segment angle of a line segment existing in the local map and determining a traveling direction; And
Adjusting the running direction according to the calculated main line angle;
And a controller for controlling the cleaning robot.
19. The method of claim 18,
The step of acquiring the local map comprises:
Wherein the cleaning robot scans around the current position based on a pre-stored environment map that the cleaning robot travels to acquire the local map.
20. The method of claim 19,
Wherein the environmental map is a two-dimensional grid map or a three-dimensional grid map.
19. The method of claim 18,
The step of acquiring the local map comprises:
The virtual robot may extract the virtual sensor data by performing a ray casting technique on all directions while rotating 360 degrees from the virtual sensor data extraction position centered on the current position of the cleaning robot to acquire the local map,
And extracting from the environment map a local map having a predetermined size centered on each of the plurality of local map extraction positions centered on the current position of the cleaning robot.
19. The method of claim 18,
Wherein the step of determining the current position coordinates comprises:
Obtaining a plurality of corresponding points through data matching between the real sensor data and the local map;
Calculating a relative position of the real sensor data with respect to the local map using the obtained plurality of corresponding points;
Calculating a degree of similarity between the plurality of local maps and the real sensor data; And
Determining a current position of the cleaning robot with respect to the local map having the largest degree of similarity as a current position of the cleaning robot with respect to the environment map;
And a controller for controlling the cleaning robot.
23. The method of claim 22,
In calculating the similarity,
And determines that the degree of similarity is higher as the number of data points commonly included in the local map and the actual sensor data increases.
19. The method of claim 18,
Wherein the step of determining the running direction comprises:
Obtaining a plurality of straight lines in the local map; And
Calculating a main line segment angle by classifying the plurality of straight lines according to an angle;
And a controller for controlling the cleaning robot.
25. The method of claim 24,
Wherein the step of calculating the main line segment angle comprises:
Generating an angle histogram by classifying the plurality of straight lines according to angles; And
Determining the main line segment angle in consideration of the distribution of the angle histogram;
And a controller for controlling the cleaning robot.
26. The method of claim 25,
Wherein the step of calculating the main line segment angle comprises:
Merging orthogonal or parallel straight lines in the angular histogram;
And a control unit for controlling the cleaning robot.

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