WO2021141200A1

WO2021141200A1 - Robot cleaner and method for controlling the same

Info

Publication number: WO2021141200A1
Application number: PCT/KR2020/010858
Authority: WO
Inventors: Byoungsuk Choi
Original assignee: Lg Electronics Inc.
Priority date: 2020-01-10
Filing date: 2020-08-19
Publication date: 2021-07-15
Also published as: KR20210090447A

Abstract

Provided is a method for controlling a robot cleaner including a first operation of traveling, by a body, straight ahead along an initial direction where the body is directed from an initial location where the body is placed while sucking dust, a second operation of setting a front boundary of a region where cleaning is performed when a sucked amount of dust is maintained equal to or below a certain value during the travel, and a third operation of traveling by switching a direction when the front boundary is set.

Description

ROBOT CLEANER AND METHOD FOR CONTROLLING THE SAME

The present disclosure relates to a robot cleaner and a method for controlling the same, and more particularly, to a robot cleaner and a method for controlling the same with an improved cleaning performance.

In general, a vacuum cleaner is an apparatus that sucks air containing foreign substances from the outside by driving of an air suction apparatus that is disposed in a cleaner body to generate an air suction force, and then separates and collects the foreign substances.

The vacuum cleaner that performs the above functions is classified into a manual vacuum cleaner that is directly manipulated by a user and a robot cleaner that performs cleaning by itself without the user manipulation. The robot cleaner performs a function of sucking various foreign substances placed on a face to be cleaned while autonomously traveling on the face to be cleaned.

Korean Patent Registration 10-1499966 conceptually discloses a technology of sensing a sucked amount of dust through an infrared sensor and adjusting the sucked amount. However, the prior art does not provide other technical benefits for user convenience using obtained sucked amount of dust information. There is a need to satisfy a user's desire to receive various measures to improve a cleaning performance using the sucked amount of dust information.

The present disclosure is to solve the above problems, and relates to a robot cleaner and a method for controlling the same that may set a region that needs cleaning using sucked amount of dust information.

In addition, the present disclosure relates to a robot cleaner and a method for controlling the same capable of cleaning in consideration of an amount of dust around a location to which the robot cleaner has moved.

The present disclosure relates to a robot cleaner and a method for controlling the same in which the robot cleaner senses a sucked amount of dust while traveling and sets a travel direction based on the sensed sucked amount of dust, so that the robot cleaner is able to perform cleaning while traveling in consideration of the sucked amount of dust.

In addition, the present disclosure relates to a robot cleaner and a method for controlling the same capable of setting a region that needs cleaning, and accumulating data for intensively cleaning the corresponding region when the cleaning is performed in the future using the corresponding information.

The present disclosure provides a method for controlling a robot cleaner including a first operation of traveling, by a body, straight ahead along an initial direction where the body is directed from an initial location where the body is placed while sucking dust, a second operation of setting a front boundary of a region where cleaning is performed when a sucked amount of dust is maintained equal to or below a certain value during the travel, and a third operation of traveling by switching a direction when the front boundary is set.

The front boundary may be a portion where the sucked amount of dust during the travel starts to be equal to or below the certain value.

The second operation may include setting the front boundary after passing through the front boundary and then further traveling by a certain distance.

The third operation may include traveling in a direction parallel to the initial direction but opposite to the initial direction.

The third operation may include traveling to pass the initial location.

The method may further include a fourth operation of setting a rear boundary of the region where the cleaning is performed when the sucked amount of dust is maintained equal to or below the certain value during the travel.

The method may further include a fifth operation of traveling in a direction opposite to the travel direction in the third operation when the rear boundary is set, then moving to the rear boundary, and then rotating and traveling in a direction perpendicular to the travel direction.

The method may further include a sixth operation of setting a lateral boundary of the region where the cleaning is performed when the sucked amount of dust is maintained equal to or below the certain value during the travel.

The lateral boundary may be a portion separated by a predetermined distance from a portion where the sucked amount of dust is equal to or above the certain value when the sucked amount of dust is maintained equal to or below the certain value during the travel.

The method may further include a seventh operation of traveling in a direction opposite to a travel direction in the sixth operation after the lateral boundary is set.

The seventh operation may include moving vertically with respect to the travel direction in the first operation and setting a lateral boundary located on an opposite side of the lateral boundary.

The method may further include an eighth operation of moving by a certain distance in a direction parallel to the travel direction in the first operation when the lateral boundary located on the opposite side is set, and then traveling in a direction opposite to the travel direction in the seventh operation.

The region traveled by the body may be divided into cells in a square shape corresponding to a size of the body.

When there are a plurality of cells in succession having the sucked amount of dust equal to or below the certain value among the divided cells, a previous cell of a cell initially located and having the sucked amount of dust equal to or below the certain value may be set as the front boundary or a rear boundary.

When there are the plurality of cells in succession having the sucked amount of dust equal to or below the certain value among the divided cells, a cell past a plurality of cells from the cell initially located and having the sucked amount of dust equal to or below the certain value may be set as a lateral boundary.

According to the present disclosure, because the cleaning region of the robot cleaner is set in consideration of the sucked amount of dust, the cleaning performance is improved. The cleaning may be performed while the robot cleaner intensively travels in the region that needs the cleaning.

In addition, according to the present disclosure, information on the region that needs the cleaning is obtained, so that the corresponding region may be cleaned intensively in the future.

FIG. 1 is a perspective view illustrating a cleaner according to an embodiment of the present disclosure.

FIG. 2 is a control block diagram according to an embodiment.

FIG. 3 is a control flow diagram according to an embodiment.

FIG. 4 is a view for illustrating an embodiment of a cleaning scheme according to a first scheme.

FIG. 5 is a view for illustrating an embodiment of a cleaning scheme according to a second scheme.

FIG. 6 is a control flowchart of another embodiment of a cleaning scheme according to a first scheme.

FIGS. 7 to 12 are views for illustrating FIG. 6.

FIG. 13 is a control flowchart of another embodiment of a cleaning scheme according to a first scheme.

FIGS. 14 to 20 are views for illustrating FIG. 13.

Hereinafter, a preferred embodiment according to the present disclosure that may specifically realize the above object will be described with reference to the accompanying drawings.

In such process, a size or a shape of a component shown in the drawings may be exaggerated for clarity and convenience of description. Moreover, terms specifically defined in consideration of the composition and operation according to the present disclosure may vary depending on the intention or custom of the user or operator. Definitions of such terms should be made based on the contents throughout this specification.

Referring to FIG. 1, a cleaner 100 includes a body 110, a cleaning nozzle 120, a sensing unit 130, and a dust collection vessel 140.

Various parts including a controller (not shown) for controlling the cleaner 100 are embedded or mounted in the body 110. The body 110 may define therein a space in which the various parts constituting the cleaner 100 are accommodated. The body 110 is equipped with a wheel unit 200 for moving the body 110. The wheel unit 200 may include a motor (not shown) and at least one wheel rotated by a driving force of the motor. A direction of rotation of the motor may be controlled by the controller (not shown). Accordingly, the wheel of the wheel unit 200 may be rotated clockwise or counterclockwise.

The wheel units 200 may be respectively arranged on both left and right sides of the body 110. The body 110 may be moved back and forth and left and right, or rotated by the wheel unit 200. The wheel units 200 may be driven independently of each other. To this end, the wheel units 200 may be respectively driven by different motors.

As the controller controls the driving of the wheel unit 200, the cleaner 100 autonomously moves on a floor. The wheel unit 200 is disposed at a lower portion of the body 110 and moves the body 110. The wheel unit 200 may be composed of circular wheels only, may be composed of circular rollers connected to each other by a belt chain, or may be composed of a combination of the circular wheels and the circular rollers connected to each other by the belt chain. An upper portion of the wheel of the wheel unit 200 may be disposed within the body 110, and a lower portion thereof may protrude downward from the body 110.

The wheel units 200 may be installed on the left and right sides of the body 110, respectively. The wheel unit 200 disposed on the left side of the body 110 and the wheel unit 200 disposed on the right side of the body 110 may be driven independently of each other. That is, the wheel unit 200 disposed on the left side of the body 110 may include at least one wheel that may be connected to each other through at least one gear and may be rotated by a driving force of a first wheel driving motor that rotates the gear. Moreover, the wheel unit 200 disposed on the right side of the body 110 may include at least one wheel that may be connected to each other through at least one gear and may be rotated by a driving force of a second wheel driving motor that rotates the gear.

The controller may determine a travel direction of the body 110 by controlling a rotational velocity of each of the first wheel driving motor and the second wheel driving motor. For example, when the first wheel driving motor and the second wheel driving motor are simultaneously rotated at the same velocity, the body 110 may move straight. Moreover, when the first wheel driving motor and the second wheel driving motor are simultaneously rotated at different velocities, the body 110 may turn left or right. The controller may drive one of the first wheel driving motor and the second wheel driving motor and stop the other to turn the body 110 to the left or right.

The body 110 is equipped with a battery (not shown) that supplies power to electrical components of the cleaner 100. The battery may be rechargeable and detachable from the body 110.

Air containing dust introduced through the cleaning nozzle 120 enters the dust collection vessel 140 through an inhale channel inside the body 110. The air and the dust are separated from each other while passing through at least one filter (e.g., a cyclone, a filter, and the like) in the dust collection vessel 140. The dust is collected in the dust collection vessel 140, and the air is exhausted from the dust collection vessel 140, then passes along an exhaust channel inside the body 110, and then finally exhausted through an exhaust port to the outside. An upper cover 113 for covering the dust collection vessel 140 accommodated in a dust collection vessel receiving portion 112 is disposed on the body 110. The upper cover 113 may be hinged to one side of the body 110 and pivotable. The upper cover 113 may cover a top of the dust collection vessel 140 by covering an open top of the dust collection vessel receiving portion 112. In addition, the upper cover 113 may be separable and detachable from the body 110. In a state in which the upper cover 113 is disposed to cover the dust collection vessel 140, the separation of the dust collection vessel 140 from the dust collection vessel receiving portion 112 may be restricted.

A handle 114 is disposed on a top of the upper cover 113. Imaging means 115 may be disposed on the handle 114. In this connection, the imaging means 115 is preferably disposed obliquely with respect to a bottom face of the body 110 to capture the front and the top together.

The imaging means 115 may be disposed on the body 110 and capture an image for simultaneous location and mapping (SLAM) of the cleaner. The image captured by the imaging means 115 is used to generate a map of a travel region or sense a current location within the travel region. The imaging means 115 may generate 3-dimensional coordinate information related to a periphery of the body 110. That is, the imaging means 115 may be a 3-dimensional depth camera (3D depth camera) that calculates a perspective distance between the cleaner 100 and an imaging target. Accordingly, field data for the 3-dimensional coordinate information may be generated.

Specifically, the imaging means 115 may capture a 2-dimensional image related to the periphery of the body 110. A plurality of 3-dimensional coordinate information corresponding to the captured 2D image may be generated. In one embodiment, the imaging means 115 may be formed in a stereo vision scheme in which at least two cameras that acquire the existing 2-dimensional images are arranged and at least two images respectively acquired from the at least two cameras are combined with each other to generate the 3-dimensional coordinate information.

The imaging means 115 may include a first pattern irradiating unit that irradiates light of a first pattern downward toward the front of the body, a second pattern irradiating unit that irradiates light of a second pattern upward toward the front of the body, and an image acquisition unit that acquires an image of the front of the body. Thus, the image acquisition unit may acquire an image of a region into which the light of the first pattern and the light of the second pattern are incident.

Further, the imaging means 115 is equipped with an infrared pattern emitter that irradiates an infrared pattern together with a single camera. A distance between the imaging means 115 and the imaging target may be measured by capturing a shape of the infrared pattern irradiated from the infrared pattern emitter projected onto the imaging target. The imaging means 115 may be an infrared (IR) imaging means 115.

In one example, the imaging means 115 is equipped with a light emitter that emits light together with the single camera. The imaging means 115 may receive a portion reflected from the imaging target of laser emitted from the light emitter and analyze the received laser to measure the distance between the imaging means 115 and the imaging target. Such imaging means 115 may be imaging means 115 of a time of flight (TOF) scheme.

The imaging means 115 as above is configured to irradiate laser extending in at least one direction. In one example, the imaging means 115 may include first and second lasers. The first laser may irradiate laser in a shape in which straight lines intersect each other, and the second laser may irradiate laser in a shape of a single straight line. Thus, the bottommost laser is used to sense an obstacle at a lower portion, the topmost laser is used to sense an obstacle at a upper portion, and middle laser between the bottommost laser and the topmost laser is used to sense an obstacle in a middle portion.

The sensing unit 130 may be disposed below the upper cover 113, and the sensing unit 130 may be detachably coupled to the dust collection vessel 140.

The sensing unit 130 is disposed on the body 110 and senses information related to an environment where the body 110 is located. The sensing unit 130 senses information related to the environment to generate field data.

The sensing unit 130 senses a terrain feature (including the obstacle) such that the cleaner 100 does not collide with the obstacle. The sensing unit 130 may sense external information of the cleaner 100. The sensing unit 130 may sense a user around the cleaner 100. The sensing unit 130 may sense an object around the cleaner 100.

In addition, the sensing unit 130 is configured to perform panning (moving in a left and right direction) and tilting (disposed obliquely in an up and down direction) to improve a sensing function of the cleaner and a travel function of the robot cleaner.

The sensing unit 130 may include at least one of an external signal sensor, an obstacle sensor, a cliff sensor, a lower camera sensor, an upper camera sensor, a current sensor, an encoder, an impact sensor, and a microphone.

The external signal sensor may sense an external signal of the cleaner 100. The external signal sensor may be, for example, an infrared ray sensor, an ultrasonic sensor, a radio frequency sensor, and the like. Accordingly, field data for the external signal may be generated.

The cleaner 100 may sense information about a location and a direction of a charging device by receiving a guide signal generated by the charging device using the external signal sensor. In this connection, the charging device may transmit the guide signal indicating the direction and a distance such that the cleaner 100 is able to return. That is, the cleaner 100 may receive the signal transmitted from the charging device to determine the current location and set a moving direction to return to the charging device.

The obstacle sensor may sense a front obstacle. Accordingly, field data for the obstacle is generated. The obstacle sensor may sense an object existing in the moving direction of the cleaner 100 and transmit the generated field data to the controller. That is, the obstacle sensor may sense a protrusion, a fixture in the house, furniture, a wall face, a wall edge, and the like existing on a moving path of the cleaner 100 and transmit field data thereof to the controller. The obstacle sensor may be, for example, an infrared sensor, an ultrasonic sensor, an RF sensor, a geomagnetic sensor, and the like. The cleaner 100 may use one type of sensor or, when it is necessary, at least two types of sensors together as the obstacle sensor.

The cliff sensor may sense an obstacle on the floor that supports the body 110 mainly using various types of light sensors. Accordingly, field data for the obstacle on the floor is generated. The cliff sensor may be an infrared sensor, an ultrasonic sensor, an RF sensor, a position sensitive detector (PSD) sensor, and the like equipped with a light emitter and a light receiver like the obstacle sensor.

For example, the cliff sensor may be the PSD sensor, but may be composed of a plurality of different types of sensors. The PSD sensor includes a light emitter that emits infrared light on the obstacle, and a light receiver that receives the infrared light reflected from the obstacle, and is generally formed in a module shape. When the obstacle is sensed using the PSD sensor, a stable measurement may be obtained regardless of a reflectance of the obstacle and a color difference.

The controller may sense a cliff by measuring an infrared light angle between an emission signal of the infrared light emitted by the cliff sensor toward the ground and a reflection signal of the infrared light reflected by the obstacle and received, and may acquire field data of a depth of the cliff.

The cliff sensor may sense a material of the floor. The cliff sensor may sense a reflectance of light reflected from the floor, and the controller may determine the material of the floor based on the reflectance. For example, when the material of the floor is marble with good reflectance, the reflectance of the light sensed by the cliff sensor will be high. When the material of the floor is wood, a floor paper, a carpet, and the like whose reflectance is relatively poor compared to the marble, the reflectance of the light sensed by the cliff sensor will be relatively low. Therefore, the controller may determine the material of the floor using the reflectance of the floor sensed by the cliff sensor, and may determine the floor as the carpet when the reflectance of the floor is a set reflectance.

Moreover, the cliff sensor may sense a distance from the floor, and the controller may sense the material of the floor based on the distance from the floor. For example, when the cleaner is located on the carpet on the floor, the distance from the floor sensed by the cliff sensor will be sensed smaller than when the cleaner is located on the floor without the carpet. Therefore, the controller may determine the material of the floor using the distance from the floor sensed by the cliff sensor. When the distance from the floor is equal to or greater than a set distance, the floor may be determined as the carpet.

The lower camera sensor acquires image information (field data) about a face to be cleaned while the cleaner 100 is moving. The lower camera sensor may be referred to as an optical flow sensor. The lower camera sensor may generate an image data (field data) of a predetermined format by converting an image of a lower portion input from an image sensor disposed in the sensor. The field data about the image recognized through the lower camera sensor may be generated. Using the lower camera sensor, the controller may detect a position of a mobile robot regardless of sliding of the mobile robot. The controller may compare and analyze the image data captured by the lower camera sensor over time to calculate a moved distance and the moving direction, and calculate the position of the mobile robot based on the moved distance and the moving direction.

The lower camera sensor may capture the floor, and the controller may determine the material of the floor by analyzing the image captured by the lower camera sensor. Images corresponding to the material of the floor may be set in the controller. Further, when the set image is included in the images captured by the camera sensor, the controller may determine the material of the floor as a material corresponding to the set image. When the set image corresponding to an image of the carpet is included in the images, the material of the floor may be determined as the carpet.

The upper camera sensor may be installed to be directed upward or forward of the cleaner 100 to capture a region around the cleaner 100. When the cleaner 100 is equipped with a plurality of upper camera sensors, the camera sensors may be formed on a top or a side of the mobile robot at a certain distance or a certain angle. Field data about an image recognized through the upper camera sensor may be generated.

The current sensor may sense a current resistance of the wheel driving motor, and the controller may determine the material of the floor based on the current resistance sensed by the current sensor. For example, when the cleaning nozzle 120 is placed on the carpet on the floor, a pile of the carpet may be sucked through an intake of the cleaning nozzle 120 and interrupt the travel of the cleaner. At this time, current resistance due to load will be generated between a rotor and a stator of the wheel driving motor. The current sensor may sense the current resistance generated from the wheel driving motor. In addition, the controller may determine the material of the floor based on the current resistance, and may determine the material of the floor as the carpet when the current resistance is equal to or greater than a preset value.

The encoder may sense information related to the operation of the motor operating the wheel of the wheel unit 200. Accordingly, field data about the operation of the motor is generated.

The impact sensor may sense an impact generated when the cleaner 100 collides with an external obstacle and the like. Accordingly, field data about the external impact is generated.

The microphone may sense external sound. Accordingly, field data about the external sound is generated.

FIG. 2 is a control block diagram according to an embodiment.

Referring to FIG. 2, the sensing unit 130 may include a dust sensor 131 that measures an amount of dust. The dust sensor 131 may measure a sucked amount of dust when sucking the dust while the cleaning of the robot cleaner is performed. The dust sensor 131 may be disposed on a suction duct through which the dust is sucked to measure the amount of duct sucked through the suction duct. The dust sensor 131 may measure the amount of dust using a scheme of measuring vibration or noise generated at the suction duct. The fact that the vibration or the noise is generated a lot when a lot of dust moves in the suction duct is used. In addition, the dust sensor 131 may use a scheme of measuring the amount of dust sucked through the suction duct using an infrared ray. The amount of dust may be measured based on a received amount of transmitted infrared ray. Information on the amount of dust obtained by the dust sensor 131 may be transmitted to a controller 300.

The sensing unit 130 may include a wheel lift sensor 132. The wheel lift sensor 132 may be operated in a scheme in which a contact switch is turned off when the wheel is separated from the floor. When the user lifts the robot cleaner from the floor and moves the robot cleaner, because the wheel unit 200 is lifted by the user, the contact switch of the wheel lift sensor 132 is turned off. Thus, the wheel lift sensor 132 may sense that the robot cleaner is lifted from the floor. Information sensed by the wheel lift sensor 132 may be transmitted to the controller 300.

The sensing unit 130 may include a cliff sensor 133. The cliff sensor 133 measures a distance between the robot cleaner and the floor to sense that the robot cleaner is lifted from the floor. When the user lifts the robot cleaner, a height sensed by the cliff sensor 133 changes rapidly, so that the cliff sensor 133 may sense a situation in which the user lifts and moves the robot cleaner. Information sensed by the cliff sensor 133 may be transmitted to the controller 300.

The sensing unit 130 may include a remote control receiver 134. The remote control receiver 134 is composed of an infrared sensor to sense a remote control manipulation signal of the user. The robot cleaner may travel while avoiding the obstacle based on information sensed by itself, but may be moved by a remote control used by the user. In this connection, the remote control may be a smartphone used by the user. After moving the robot cleaner to a desired location using the remote control, the user may start the cleaning at the moved location. After information received from the remote control receiver 134 is transmitted to the controller 300, the controller 300 may execute a corresponding command.

The sensing unit 130 may include a remote signal receiver 135. The remote signal receiver 135 is composed of a Wi-Fi module to sense a user manipulation signal from a remote device. The remote signal receiver 135 may sense the signal manipulated by the user, and thus sense a situation in which the movement is performed by an intention of the user, not the information sensed by the robot cleaner. Information sensed by the remote signal receiver 135 may be transmitted to the controller 300.

The sensing unit 130 may include a location sensor 136. The location sensor 136 may include a vision/distance sensor using a camera, a laser, and the like. A change in the location of the robot cleaner may be sensed using an image acquired from the camera or transmission and reception of the laser. Information obtained by the location sensor 136 may also be transmitted to the controller 300.

The controller 300 may include a driving motor 310 that drives the wheel of the wheel unit 200. The controller 300 may generate a signal for driving the driving motor 310.

The controller 300 may control driving of a suction apparatus 320 that changes a suction force for sucking the dust through the cleaning nozzle 120. The controller 300 may control such that the suction force is strong at the suction apparatus 320 or such that the suction force is weak at the suction apparatus 320. The suction apparatus 320 may include a fan capable of adjusting the suction force for sucking the dust through the cleaning nozzle 120.

FIG. 3 is a control flow diagram according to an embodiment.

Referring to FIG. 3, an embodiment includes a first operation of identifying that the body 110 has been moved by the user, a second operation of sucking, by the body 110, the dust while traveling, and a third operation of performing cleaning in a first scheme when the sucked amount of dust is greater than a set value, and performing cleaning in a second scheme when the sucked amount of dust is equal to or less than the set value.

That is, in the first operation, whether the change in the location of the cleaner has occurred by the user is sensed (S10). In this connection, the various sensors of the sensing unit 130 may sense whether the user has moved the body 110. In this connection, the case that the change in the location has occurred by the user may mean cases except for a case in which the robot cleaner moves based on autonomous determination in a situation in which the cleaning is performed, such as avoiding the obstacle while traveling.

The movement of the body 110 by the user may include a movement of the body 110 irrespective of the rotation of the wheel unit 200. That is, the movement of the body 110 by the user may mean the change in the location of the body in a state in which the wheel unit 200 is not driven.

In addition, the movement of the body 110 by the user may include movement to a location separated from a charger for charging the robot cleaner. The charger is a component to which the body 110 is docked to charge the battery disposed in the body. When the robot cleaner is moved away from the charger, it may be determined that the movement of the robot cleaner has occurred. In one example, it may not be concluded that the change in the location of the cleaner has occurred by the user even when the robot cleaner is moved to the location separated from the charger.

In addition, the movement of the body 110 by the user may include a case in which the wheel lift sensor 132 senses that the wheel unit 200 is separated from the floor. When the user lifts and moves the body 110, the wheel unit 200 is not able to be in contact with a floor face, and such a situation may be sensed by the wheel lift sensor 132.

The dust is sucked through the cleaning nozzle 120 while the cleaning is performed in a state in which the location is changed (S20). In this connection, the dust existing on the travel path of the robot cleaner may be sucked while the body 110 moves as the suction apparatus 320 is driven. In this connection, the body 110 may travel a certain distance in a linear direction from a current state of being placed. For example, the body 110 is able to suck the dust while traveling a distance of about 2 to 3 times the size of the body. In one example, the body 110 is able to travel further distances. In addition, the body 110 may move by a total travel distance that corresponds several times the size of the body while traveling in a direction of being placed and avoiding the obstacle when encounters the obstacle.

After the dust is sucked, the sucked amount of dust and the set value are compared with each other (S30). In this connection, the sucked amount of dust may be measured by the dust sensor 131. The body 110 compares the sucked amount of dust with the set value while moving by the certain distance. Therefore, even when there is a lot of dust or less dust only at a specific location where the body 110 is placed, because the sucked amount of dust is considered while traveling by the certain distance, it may be determined whether a surrounding region in which the body 110 is placed has more or less dust than the set value.

When the sucked amount of dust is greater than the set value, the cleaning may be performed using the first scheme (S40). On the other hand, when the sucked amount of dust is less than or equal to the set value, the cleaning may be performed using the second scheme (S50).

When the sucked amount of dust is greater than the set value, it is determined that there is a lot of dust around the robot cleaner and it is preferable to focus on cleaning the region around the robot cleaner. Therefore, the first scheme is a scheme that intensively performs the cleaning on a surrounding space, not an entire space in which the robot cleaner is able to move. Based on the first scheme, it is possible to increase the suction force in the suction apparatus 320, so that the sucked amount of dust may be increased. The cleaning using the first scheme may be referred to as an intensive cleaning mode because the cleaning is concentrated on the region around the specific location where the robot cleaner is placed. Alternatively, it may also be referred to as a partial cleaning mode.

When the sucked amount of dust is less than or equal to the set value, it is determine that there is not much dust around the robot cleaner and it is preferable to clean the entire space where the robot cleaner may travel. Therefore, in the second scheme, the robot cleaner is able to perform the cleaning while traveling in a wider space compared to the first scheme until encounter the obstacle. Because the cleaning using the second scheme is the cleaning of the entire space in which the robot cleaner is placed, the second scheme may be referred to as a general cleaning mode unlike the first scheme. Alternatively, the second scheme may also be referred to as a full cleaning mode.

The first scheme and the second scheme will be described in detail below using different drawings.

Referring to FIG. 4, in the first scheme, even when the body 110 does not encounter the obstacle during the travel, the cleaning is performed as a direction is switched. That is, the body 110 may have a travel path in a spiral shape around a location placed by the user. The body 110 may travel in a scheme of being further away from the certain location in a square spiral shape. Accordingly, even when the body 110 does not encounter the obstacle during the travel, the travel may be achieved while the body 110 moves further away from a center of the square spiral shape. In addition, the cleaning of the path through which the body 110 travels may be performed while the travel is performed.

In addition, in the first scheme, the body 110 may travel only within a set range from the certain location, and stop travel and terminate the cleaning at a location out of the set range. In this connection, the set range may not be the entire region in which the robot cleaner may travel, but a range determined based on a current location of the robot cleaner. The set range may be set to a fixed distance such as 1.5 m forward and 1.5m rearward of the robot cleaner. That is, even when there is a space for the body 110 to perform the cleaning while additionally traveling as shown in FIG. 4, the body 110 travels only within the preset range and terminates the cleaning.

Although a space divided by a wall 400 remains, the robot cleaner may only perform the cleaning to a location where an arrow stops and terminate the cleaning. Finally, the first scheme is a scheme of not performing the cleaning for a portion of the space divided by the wall 400 even though the robot cleaner is able to travel. It may be determined that the user is desired to perform the cleaning around the location where the user placed the robot cleaner, and the cleaning may be performed in the first scheme.

Referring to FIG. 5, the second scheme may mean a scheme in which the cleaning is performed while the body 110 travels straight ahead until encountering the obstacle during the travel. That is, when not encountering the obstacle during the travel, the body 110 travels while maintaining a current direction until encountering the wall 400, which is a boundary of the travelable space. When encountering the obstacle or the wall 400, the body 110 may perform the cleaning while switching the direction and then traveling.

In the second scheme, the cleaning may be terminated after the body 110 travels in the entire travelable space. The space in which the body 110 may travel may mean a space, which is isolated from the outside, on the basis of a location where the body 110 is placed. In other words, it may mean a portion partitioned from a portion, which is an external boundary such as the wall 400, centered on the space in which the body 110 is placed. The cleaning may be terminated after the body 110 cleans the entire travelable space from the state of being placed after the user moves the body 110.

In one example, in the second operation, the body 110 may suck the dust while traveling straight ahead from the state of being placed on the floor. That is, the body 110 may perform the cleaning while traveling straight ahead while maintaining a direction of being placed from the state of being moved by the user.

FIG. 6 is a control flowchart of another embodiment of a cleaning scheme according to a first scheme, and FIGS. 7 to 12 are views for illustrating FIG. 6.

Another embodiment will be described with reference to FIGS. 6 to 12. Another embodiment includes a first operation of traveling while traveling straight ahead from an initial location where the body 110 is placed along an initial direction in which the body 110 is directed while sucking the dust, a second operation of setting a front boundary of a region where the cleaning is performed when the sucked amount of dust is kept equal to or below the certain value during the travel, and a third operation of switching the direction and traveling when the front boundary is set.

This is able to be applied all cases when the body 110 newly starts the cleaning after stopping the cleaning in a state in which the user has moved the body 110 or the body 110 has moved by itself. When the body 110 starts the cleaning even when the body 110 has not moved by the user, a location and a direction at a time point at which the cleaning is started may be respectively set as the initial location and the initial direction.

As shown in FIG. 7, the body 110 moves straight ahead from the initial location in the initial direction in which the body 110 is directed. In this connection, the initial direction may mean a direction in which the body 110 travels when the wheel units 200 respectively located on the both sides of the body 110 are driven in the state in which the body 110 is placed (S110). In this connection, the body 110 travels straight ahead along the travel direction.

The body 110 sucks the dust through the cleaning nozzle 120 while traveling. Because the body 110 sucks the dust while traveling, the dust sucked through the cleaning nozzle 120 includes not only dust from the initial location, but also dust sucked from the path moved along the initial travel direction from the initial location.

While sucking the dust through the cleaning nozzle 120, the dust sensor 131 measures the sucked amount of dust.

As shown in FIG. 8, when the sucked amount of dust is maintained equal to or below the certain value during the travel, the front boundary of the region where the cleaning is performed is set (S110). When the sucked amount of dust is maintained equal to or above the certain value during the travel, the body 110 determines that there is a lot of dust around and continues to travel without setting the boundary at a corresponding location. In this connection, an outer side of the boundary refers to a space where the cleaning is not performed, and an inner side of the boundary refers to a space where the cleaning is performed. The robot cleaner may provide a mode of setting the boundary and intensively cleaning the inner side of the boundary. When the sucked amount of dust is kept equal to or below the certain value, it may be determined that less dust exists in the surrounding region. Therefore, it may mean that the cleaning is not necessary for the region beyond the boundary, and it may be determined that urgency of the cleaning is low.

In this connection, the front boundary may be set after passing through the front boundary and further traveling by a certain distance. The body 110 compares the sucked amount of dust with the certain value after traveling within a range beyond an expected boundary to determine whether to set the front boundary based on whether the sucked amount of dust is equal to or above, or equal to or below the certain value. Therefore, the body 110 travels while comparing and determining the sucked amount of dust, but no longer travels in the initial direction when the sucked amount of dust decreases to be equal to or below the certain value.

The certain value described above may be variously changed by the user. For example, when the certain value is lowered, the body 110 may set a region that needs the cleaning large even though there is a relatively small amount of dust, so that a size of the space to be cleaned may be increased. Therefore, there is an advantage that the cleaning may be performed in a large area.

On the other hand, when the certain value is increased, the body 110 may set the region that needs the cleaning small even though there is a relatively large amount of dust, so that an area that the robot cleaner travels is reduced. Therefore, there is an advantage that the cleaning may be performed while traveling in a short time for the space with a lot of dust. When the user wants to rapidly clean the space with a lot of dust, the user may increase the certain value.

In addition, the certain value may be changed based on a user's situation. Sometimes, the robot cleaner may be driven by lowering the certain value, and sometimes, the robot cleaner may be driven by increasing the certain value.

When the front boundary is set as shown in FIG. 9, the body switches the direction and moves (S120). In this connection, the body 110 moves to the initial location after rotating 360 degrees with respect to the initial travel direction. The travel direction of the body 110 is parallel to the initial direction, but is opposite to the initial direction. The body 110 travels to pass the initial location, and the space in which the cleaning is performed by the body 110 from the initial location to the front boundary is defined.

Even after passing the initial location, the body 110 continues to travel straight ahead (S130). In this connection, as the dust is continuously sucked through the cleaning nozzle 120, the dust sensor 131 continuously senses whether the sucked amount of dust is equal to or less than the certain value. In one example, because the dust is sucked through the cleaning nozzle 120 while the body 110 is traveling, the cleaning of the floor is performed even in the process of setting the boundary.

As shown in FIG. 10, when the sucked amount of dust is maintained to be equal to or below the certain value during the travel, a rear boundary of the region where the cleaning is performed is set (S140). Similar to the scheme of setting the front boundary, the body 110 senses the sucked amount of dust while the traveling. When the sucked amount of dust is equal to or less than the certain value, the body 110 stops travel and rotates to be directed in a direction opposite to the travel direction. In this connection, the body 110 may travel by rotating 360 degrees with respect to the existing travel direction. When both the front boundary and the rear boundary are set, it is defined that the body performs the cleaning only within a region inward of the front boundary and the rear boundary in a front and rear direction. When the state in which the sucked amount of dust has been reduced to be equal to or below the certain value is continuously maintained, a portion where the amount of dust started to decrease may be set as the rear boundary like the front boundary.

As shown in FIG. 11, when the rear boundary is set, after moving to the rear boundary, the body 110 rotates and travels in a direction perpendicular to the travel direction (S150). In the state in which the front and rear boundaries are defined as described above, the robot cleaner continuously travels to define left and right boundaries. When the sucked amount of dust is maintained equal to or below the certain value during the travel, the body 110 sets a lateral boundary of the region where the cleaning is performed (S160). As shown in FIG. 11, when the body 110 rotates to the right and travels from the rear boundary, a right boundary for the rear boundary may be defined.

In particular, the lateral boundary may be a portion separated by a predetermined distance from a portion where the sucked amount of dust is equal to or above the certain value when the state in which the sucked amount of dust is equal to or below the certain value during the travel is maintained. The lateral boundary may refer to a location where a portion where the sucked amount of dust is equal to or below the certain value starts. Alternatively, the lateral boundary may be a portion separated by a predetermined distance from the location where the portion where the sucked amount of dust is equal to or below the certain value starts.

After the lateral boundary is set, the body 110 sucks the dust while traveling in the direction opposite to the travel direction (S170). When the right boundary is set as in FIG. 11, the body 110 may travel in the opposite direction to set a left boundary. In this connection, the travel direction is the direction perpendicular to the initial travel direction of the body 110. The left boundary is set with the same scheme as the scheme of setting the right boundary (S180).

When the process of FIG. 11 is repeated, the region that needs the cleaning may be defined as shown in FIG. 12. The region that needs the cleaning means a region defined by the front boundary, the rear boundary, and the lateral boundary. Because the body 110 performs the cleaning while moving an entirety of the space partitioned by the front boundary, the rear boundary, and the lateral boundary while traveling, an entirety of the region inward of the boundaries may be cleaned.

Information on the region defined by the boundaries is mapped with existing map information by the controller 300 or stored in various forms, so that the cleaning may be performed intensively on the corresponding region in the future.

The body 110 moves in the direction perpendicular to the travel direction at the time when setting the front boundary and the rear boundary, and then travels again in the direction parallel to the initial travel direction after setting both the left and right boundaries to set left and right boundaries again at a corresponding location. When the left or right boundary is set, the body 110 moves a certain distance in the direction parallel to the initial travel direction, then rotates again to the perpendicular direction, and then moves again to set the right boundary or the left boundary.

That is, there is a difference in that the front boundary and the rear boundary are able to be set through one travel, but the lateral boundary is set through continuous travel. Even with the same right boundary, a location of the right boundary may be changed based on the location of the body 110 along the initial travel direction.

FIG. 13 is a control flowchart of another embodiment of a cleaning scheme according to a first scheme, and FIGS. 14 to 20 are views for illustrating FIG. 13.

The body sets the boundaries of the regions that needs the cleaning while traveling based on a sequence of FIGS. 14 to 20. Hereinafter, portions overlapping with the above-described embodiments will be omitted, and only portions having differences will be described.

In another embodiment, a scheme of dividing the region in which the body 110 travels into cells in a shape of a rectangle corresponding to the size of the body, setting the boundaries when the sucked amounts of dust in the respective divided cells are equal to or below the certain value, and cleaning a region inward of the corresponding boundaries will be described. In FIGS. 14 to 20, one grid is a division of the region that is determined or to be determined as each cell while the body travels, a darkly colored portion is a portion where the amount of dust is greater than the certain value, and an unpainted portion is a portion where the amount of dust is less than the certain value.

The body 110 travels while dividing the region in which the body travels into the cells in the square shape corresponding to the size of the body. In this connection, when the body 110 has never passed a corresponding location, the body 110 may travel while dividing the region into the respective cells using an encoder value of the wheel rotated in the wheel unit 200. In one example, the size of the cell may be larger or smaller than the size of the body 110.

The body 110 sucks the dust through the cleaning nozzle 120 while moving. The body 110 travels while the dust sensor 131 senses the sucked amount of dust.

The body 110 sucks the dust while moving, and determines whether the dust is distributed in each cell such that the amount of dust is equal to or below the certain value (S210). In this connection, the certain value may be the same as or differently set form the certain value in the embodiment described above.

When the dust is distributed in a corresponding cell such that the amount of dust is equal to or below the certain value, the corresponding cell is set as a first cell (S220). In this connection, the first cell may mean a cell that does not need to be cleaned based on criteria set by the user because the dust is distributed such that the amount of dust is equal to or below the certain value. In one example, even when the corresponding cell is set as the first cell, when the corresponding cell is located within the boundaries of the region that needs the cleaning, the corresponding cell is disposed in the region in which the body 110 travels and the cleaning is performed.

When the dust is not distributed in the corresponding cell such that the amount of dust is equal to or below the certain value, the cell is set as the second cell (S250). In this connection, a second cell may mean a cell that needs to be cleaned based on the criteria set by the user because the dust is distributed such that the amount of dust is above the a certain value. Accordingly, the corresponding cell is defined as being within the boundaries of the region that needs the cleaning. The corresponding cell is disposed in the region where the body 110 travels, and the cleaning is performed.

Whether the number of cells set as the first cell is equal to or above a set number is determined (S230). The body 110 may continue to travel, and may define a new cell while traveling and determine whether the corresponding cell is the first cell or the second cell. The controller 300 may calculate a travel distance using the number of rotations of the wheel when the wheel unit 200 is rotated, and the dust sensor 131 may compare the sucked amount of dust with the certain value to determine a property of each cell.

When the number of first cells in succession is equal to or above the set number, an initial first cell among the first cells in succession is set as the boundary (S240). That is, even though the body 110 determines a certain cell as the first cell while traveling, the corresponding first cell may not always become the boundary. When the number of cells in succession determined as the first cells is equal to or above the set number, because the first cell initially located is set as the boundary, the body travels beyond the boundary even when there is an expected boundary.

In another embodiment, when there are a plurality of cells in succession with the sucked amounts of dust equal to or below the certain value among the divided cells, a previous cell of a cell that is initially located and has the sucked amount of dust equal to or below the certain value may be set as the front boundary or the rear boundary.

In another embodiment, when there are the plurality of cells in succession with the sucked amounts of dust equal to or below the certain value among the divided cells, a cell past a plurality of cells from the cell that is initially located and has the sucked amount of dust equal to or below the certain value may be set as the lateral boundary.

In other words, the scheme of setting the front and rear boundaries and the scheme of setting the side boundary may be different from each other.

The present disclosure may not be limited to the embodiment described above. As may be seen from the appended claims, the present disclosure may be modified by a person having ordinary knowledge in the field to which the present disclosure belongs, and such modification may belong to the scope of disclosure.

Claims

A method for controlling a robot cleaner, the method comprising:

a first operation of traveling, by a body, straight ahead along an initial direction where the body is directed from an initial location where the body is placed while sucking dust;

a second operation of setting a front boundary of a region where cleaning is performed when a sucked amount of dust is maintained equal to or below a certain value during the travel; and

a third operation of traveling by switching a direction when the front boundary is set.
The method of claim 1, wherein the front boundary is a portion where the sucked amount of dust during the travel starts to be equal to or below the certain value.
The method of claim 2, wherein the second operation includes setting the front boundary after passing through the front boundary and then further traveling by a certain distance.
The method of claim 1, wherein the third operation includes traveling in a direction parallel to the initial direction but opposite to the initial direction.
The method of claim 4, wherein the third operation includes traveling to pass the initial location.
The method of claim 4, further comprising:

a fourth operation of setting a rear boundary of the region where the cleaning is performed when the sucked amount of dust is maintained equal to or below the certain value during the travel.
The method of claim 6, further comprising:

a fifth operation of traveling in a direction opposite to the travel direction in the third operation when the rear boundary is set, then moving to the rear boundary, and then rotating and traveling in a direction perpendicular to the travel direction.
The method of claim 7, further comprising:

a sixth operation of setting a lateral boundary of the region where the cleaning is performed when the sucked amount of dust is maintained equal to or below the certain value during the travel.
The method of claim 8, wherein the lateral boundary is a portion separated by a predetermined distance from a portion where the sucked amount of dust is equal to or above the certain value when the sucked amount of dust is maintained equal to or below the certain value during the travel.
The method of claim 8, further comprising:

a seventh operation of traveling in a direction opposite to a travel direction in the sixth operation after the lateral boundary is set.
The method of claim 10, wherein the seventh operation includes moving vertically with respect to the travel direction in the first operation and setting a lateral boundary located on an opposite side of the lateral boundary.
The method of claim 10, further comprising:

an eighth operation of moving by a certain distance in a direction parallel to the travel direction in the first operation when the lateral boundary located on the opposite side is set, and then traveling in a direction opposite to the travel direction in the seventh operation.
The method of claim 1, wherein the region traveled by the body is divided into cells in a square shape corresponding to a size of the body.
The method of claim 13, wherein, when there are a plurality of cells in succession having the sucked amount of dust equal to or below the certain value among the divided cells, a previous cell of a cell initially located and having the sucked amount of dust equal to or below the certain value is set as the front boundary or a rear boundary.
The method of claim 14, wherein, when there are the plurality of cells in succession having the sucked amount of dust equal to or below the certain value among the divided cells, a cell past a plurality of cells from the cell initially located and having the sucked amount of dust equal to or below the certain value is set as a lateral boundary.