Patent Description:
In general, a mobile robot is a device that automatically cleans by suctioning foreign substances such as dust from a floor while autonomously running in a section to clean even without operation by a user.

A mobile robot can make a map of a region to clean while running in the region. A mobile robot can clean while running on the basis of a created map. A mobile robot runs while avoiding obstacles by sensing obstacles positioned in a region during running.

A mobile robot autonomously runs using the charge current stored in a battery as an operation source. A mobile robot can charge a battery by returning to a charging stand by receiving a signal that is transmitted from the charging stand.

However, a mobile robot not only has a plurality of sensors, but is configured to transmit/receive and process various signals, so there is a problem of interference of signals. There is a problem that such interference of signals generates unnecessary noise. Accordingly, a mobile robot may be interrupted due to such interference of signals when returning to a charging stand, and may sense obstacles wrong due to influence between signals.

<CIT> describes that a robot cleaner includes an IR sensor that receives IR signals of a transmitter that are transmitted in a plurality of directions, determines transmission directions in accordance with the IR signals, estimates transmission directions by removing return signals, and returns to a charging stand.

Another robot comprising an obstacle sensing unit and a docking signal receiving unit is known from document <CIT>.

This invention of the related art removes return signals of IR signals, but does not consider interference with signals, which are transmitted from sensor, etc. of a mobile robot, so there is a limit.

Accordingly, there is a need for improvement of preventing mutual interference of not only a signal of a charging stand, but a plurality of signal that a mobile robot transmits and receives, and making it easy to sense obstacles and dock with a charging stand.

An object of the present disclosure is to provide a mobile robot that minimizes signal interference between the mobile robot and a charging stand, and a method of controlling the mobile robot.

Another object of the present disclosure is to discriminate a plurality of sensor signals of a plurality of sensors using signals of the same wavelength band.

Another object of the present disclosure is to avoid interference between signals, which are output from a plurality of sensor that is disposed in a mobile robot and senses obstacles, and a docking signal of a charging stand.

Another object of the present disclosure is to minimize mis-sensing of obstacles by recognizing sensing signals of the obstacles.

Another object of the present disclosure is to return to a charging stand by recognizing a docking signal of a charging stand.

The objects of the present disclosure are not limited to those described above and other objects not stated herein may be clearly understood by those skilled in the art from the following description.

A mobile robot according to an embodiment of the present disclosure for achieving the objects and a control method thereof are characterized by discriminating a plurality of signals by discriminating signals through an operation state when a received signal is a preset signal.

The present disclosure is characterized by discriminating a plurality of signals of the same wavelength bands by determining whether a signal is a pre-agreed signal.

The present disclosure is characterized by controlling a sensing signal and a docking signal in accordance with whether a mobile robot is cleaning or moving to a destination.

The present disclosure is characterized by discriminating signals by determining whether there is noise for received signals.

The present disclosure is characterized by determining whether there is mis-sensing by comparing the pattern of a received signal.

The present disclosure is characterized by preventing interference of signals by adjusting a signal generation cycle.

The present disclosure is characterized by discriminating received signals by limiting some signal when a signal is sensed wrong.

The present disclosure is characterized by preventing interference of signals by temporarily stopping operation of some sensors in accordance with a received signal.

The present disclosure is characterized by discriminating signals in accordance with a set signal cycle of a plurality of signals of the same wavelength band.

A mobile robot of the present disclosure includes: a main body running in a region; a sensor unit disposed on a front of the main body and sensing an obstacle located at a predetermined distance from the main body by transmitting a sensing signal; a docking signal receiving unit receiving a docking signal that is transmitted from a charging stand; a running unit controlling running of the main body; and a control unit determining the location of an obstacle in response to the sensing signal, controlling running in response to an obstacle, and controlling the running unit to dock with the charging stand in accordance with the docking signal if charging is required, wherein the control unit controls the sensor unit to transmit a sensing signal with a cycle different from a signal transmission cycle of the docking signal, and determines that a signal is sensed wrong and stops operation of the sensor unit for a predetermined time when noise is generated due to overlap of the docking signal and the sensing signal.

A method of controlling a mobile robot of the present disclosure includes: sensing an obstacle by transmitting sensing signals from a plurality of sensors disposed on a front of a main body during running; determining the location of an obstacle in response to the sensing signal and performing a designated operation in response to the obstacle; stopping operation and moving to a charging stand when charging is required; determining that a signal is sensed wrong when noise is generated due to overlap of the docking signal of the charging stand and the sensing signal; stopping operation of the plurality of sensors for a designated stop time; and docking with the charging stand in accordance with the docking signal.

The mobile robot and the control method therefor of the present disclosure can minimize signal interference between the mobile robot and the charging stand.

The present disclosure can minimize signal interference of a plurality of sensor using signals of the same wavelength band and can discriminate the signals.

The present disclosure can minimize interference by determining and coping with whether there is mis-sensing due to interference of docking signal for returning to the charging stand and the sensing signal of the sensor and by adjusting transmission cycles of signals.

In the present disclosure, a plurality of sensors that senses an obstacle by discriminating a plurality of signals can easily sense an obstacle through sensing signals.

The present disclosure can minimize mis-sensing of obstacles by recognizing sensing signals of the obstacles.

The present disclosure can easily return to the charging stand by recognizing a docking signal of the charging stand.

The present disclosure can prevent misopeation of each device by minimizing signal interference of a plurality of devices that uses signals of the same wavelength band.

The present disclosure can minimize limitation in use due to signal interference for a plurality of sensors provided in a device.

The present disclosure can independently operate in the same space by minimizing signal interference with a pre-installed product.

The accompany drawings, which are included to provide a further understanding of the present disclosure and are incorporated on and constitute a part of this specification illustrate embodiments of the present disclosure and together with the description serve to explain the principles of the present disclosure.

The advantages and features of the present disclosure, and methods of achieving them will be clear by referring to the exemplary embodiments that will be describe hereafter in detail with reference to the accompanying drawings. However, the present disclosure is not limited to the exemplary embodiments described hereafter and may be implemented in various ways, and the exemplary embodiments are provided to complete the description of the present disclosure and let those skilled in the art completely know the scope of the present disclosure and the present disclosure is defined by claims. Like reference numerals indicate like components throughout the specification. A control configuration of the present disclosure may be composed of at least one process.

<FIG> is a perspective view showing a mobile robot according to an embodiment of the present disclosure.

Referring to <FIG>, a mobile robot <NUM> according to an embodiment of the present disclosure includes a main body <NUM> that suctions foreign substances such as dust on a floor while moving along the floor of a cleaning section, and a sensing unit <NUM>, <NUM> that is disposed on the front surface of the main body <NUM> and senses obstacles.

The main body <NUM> may include a casing (not shown) that forms the external shape and a space therein in which parts constituting the main body <NUM> are accommodated, a suction unit <NUM> that is disposed in the casing and suctions foreign substances such as dust or waste, and a left wheel (not shown) and a right wheel (not shown) that are rotatably provided at the casing. As the left wheel and the right wheel are rotated, the main body <NUM> moves along the floor of a cleaning section, and in this process, foreign substances are suctioned through a suction port (not shown) formed toward a floor surface.

The suction unit <NUM> may include a suction fan (not shown) that generates a suction force, and a suction port (not shown) through which airflow generated by rotation of the suction fan is suctioned. The suction unit <NUM> may include a filter (not shown) that collects foreign substances from the airflow suctioned through the suction port, and a foreign substance collection container (not shown) in which foreign substances collected by the filter are accumulated.

The suction unit <NUM> includes a rotary brush (not shown) and assists collection of foreign substances by rotating simultaneously with suctioning airflow. The suction unit is detachably configured, if necessary. The main body <NUM> may further include a plurality of brushes (not shown) positioned at the front of the bottom of the casing and having a brush composed of several wings radially extending.

Further, a damp cloth cleaning unit may be attached and detached to and from the suction unit <NUM>. The damp cloth cleaning unit may be attached to the rear surface of the suction port. Depending on cases, the damp cloth cleaning unit may be configured separately from the suction unit and may be replaced and mounted at a location where it is fastened and fixed to the suction unit. The damp cloth cleaning unit wipes a floor surface in a running direction while rotating during moving.

The main body <NUM> may include a running unit (not shown) that drives the left wheel and the right wheel. The running unit may include at least one driving motor.

The main body <NUM> may further include a plurality of brushes (not shown) positioned at the front of the bottom of the casing and having a brush composed of several wings radially extending. The plurality of brushes removes dust from the floor of a cleaning section by rotating and the dust separated from the floor in this way is suctioned through the suction port and collected in the collection container.

A control panel including an operation unit (not shown) that receives various input instructions for controlling the mobile robot <NUM> from a user may be provided on the top of the casing.

The sensing unit includes an obstacle sensing unit <NUM>, a sensor unit (not shown) composed of a plurality of sensors, and an imaging unit <NUM> that takes pictures. Depending on cases, the obstacle sensing unit <NUM> may include the imaging unit <NUM> and a sensor unit <NUM>.

As the obstacle sensing unit <NUM>, a 3D sensor that senses obstacles through an image that is taken by emitting a light pattern may be used. Further, the obstacle sensing unit <NUM> can sense obstacles in the running direction using ultrasonic waves, infrared light, and laser. The obstacle sensing unit <NUM> is composed of at least one camera and can sense obstacles from an image that is taken by the cameral.

The obstacle sensing unit <NUM> may be dispose on the front surface of the main body <NUM>.

The obstacle sensing unit <NUM> is fixed to the front surface of the casing and includes a first pattern emitter (not shown), a second pattern emitter (not shown), and a pattern obtainer (not shown). In this case, the pattern obtainer is installed at a lower portion of a pattern emitter or between the first and second pattern emitter and can take an image of an emitted pattern. The first pattern emitter and the second pattern emitter emit a patter an a predetermined emission angle.

The imaging unit <NUM> takes images in the running direction of the mobile robot <NUM>. Further, the imaging unit <NUM> can image the front in the running direction or the upper portion in the running direction, for example, a ceiling. The imaging unit <NUM> may be provided to face a ceiling or may be provided to face a front and may take images in the running direction. Further, the imaging unit <NUM> may simultaneously image the front and the upper portion of the running direction, that is, a ceiling, depending on the installation position on the main body <NUM> and an installation angle in the running direction. The imaging unit may be set such that the angle of view for imaging is different in accordance with the performance of an installed camera or the kind of a lens.

The imaging unit <NUM> is exemplified as including at least one camera in the description, and any device can be applied as long as it is an imaging unit that takes images regardless of the kinds of cameras.

The imaging unit <NUM> may include a plurality of cameras and two cameras facing the front, and a ceiling are installed on the front surface and the upper end of the main body, respectively, and can take images of the front and the ceiling, respectively. Further, the imaging unit <NUM> may include a separate camera that images a floor surface.

The sensor unit <NUM> includes an infrared sensor, an ultrasonic wave sensor, and a laser sensor and can sense obstacles. Further, the sensor unit <NUM> can sense the inclination of the main body by including an inclination sensor, for example, a tilting sensor, a gyro sensor, etc., and can sense the brightness of the region in which the main body <NUM> is positioned by including an illumination sensor.

The mobile robot <NUM> may further include a locating unit (not shown) for obtaining current location information. The mobile robot <NUM> determines the current location by including a GPS and a UWB.

A rechargeable battery (not shown) is provided in the main body, and a charging terminal (not shown) of the battery is connected to a commercial power (e.g., a power socket in home) or the main body <NUM> is docked with a separate charging stand <NUM> connected with the commercial power, so the charging terminal can be electrically connected with the commercial power through contact with a terminal <NUM> of the charging stand and the battery can be charged. Electronic parts constituting the mobile robot <NUM> can be supplied with power from the battery, and accordingly, the mobile robot <NUM> can run by itself with the battery charged in a state in which the mobile robot <NUM> is electrically separated from the commercial power.

<FIG> is a block diagram showing main parts of the mobile robot according to an embodiment of the present disclosure.

As shown in <FIG>, the mobile robot <NUM> includes a running unit <NUM>, a cleaning unit <NUM>, a data unit <NUM>, an obstacle sensing unit <NUM>, an imaging unit <NUM>, a sensor unit <NUM>, a communication unit <NUM>, an operation unit <NUM>, an output unit <NUM>, and a control unit <NUM> that controls general operation.

The operation unit <NUM> receives user input instructions by including an input unit such as at least one button, switch, a touch pad, or the like. The operation unit, as described above, may be provided at the upper end of the main body <NUM>.

The output unit <NUM> includes a display such as an LED and an LCD and displays an operation mode of the mobile robot <NUM>, schedule information, a battery state, an operation state, an error state, etc. Further, the output unit <NUM> outputs a predetermined effect sound, a warning sound, or a voice guidance corresponding to the operation mode, schedule information, battery state, operation state, and error state by including a speaker or a buzzer.

In the data unit <NUM>, obtained images input from the obstacle sensing unit <NUM> are stored, reference data for an obstacle recognizing unit <NUM> to determine obstacles are stored, and obstacle information about sensed obstacles is stored.

The data unit <NUM> stores obstacle data <NUM> for determining the kinds of obstacles, image data <NUM> storing taken images, and map data <NUM> about regions. In the map data <NUM>, obstacle information is included and various types of maps for available running regions that are searched by the mobile robot are stored.

For example, a fundamental map including information about available running regions searched by the mobile robot, a cleaning map in which regions are divided from the fundamental map, a user map created for a user to be able to recognize the shapes of regions, and a guide map in which the cleaning map and the user map are shown in an overlap state may be stored.

The obstacle data <NUM> includes the locations and sizes of sensed obstacles. Further, the obstacle data <NUM> may include information for recognizing obstacles and determining the kinds of obstacles, and information about operations set in response to obstacles. The obstacle data includes motion information about the operation of the mobile robot, for example, a running speed, a running direction, whether to avoid or not, whether to stop or not, etc., for sensed obstacles, and information about an effect sound, a warning sound, and a sound guidance that are output through the speaker <NUM>. The image data <NUM> may include taken images, for example, a still image, a video, and a panorama image.

Further, control data for controlling operation of the mobile robot, data according to a cleaning mode of the mobile robot, and sensing signals of ultrasonic wave/laser, etc. by the sensor unit <NUM> are stored in the data unit <NUM>.

Further, the data unit <NUM>, which stores data that can be read by a microprocessor, may include a storage device such as an HDD (Hard Disk Drive), an SSD (Solid State Disk), an SDD (Silicon Disk Drive), a ROM, a RAM, an EPROM, an EEPROM, a flash memory, etc..

The communication unit <NUM> communicates with a terminal <NUM> in a wireless communication type. Further, the communication unit <NUM> can communicate with an external server <NUM> or a terminal <NUM> that controls the mobile robot by being connected to the internet through a home network.

The communication unit <NUM> transmits a created map to the terminal <NUM>, receives a cleaning instruction from the terminal, and transmits data about the operation state and cleaning state of the mobile robot to the terminal. Further, the communication unit <NUM> can transmit information about obstacles sensed during running to the terminal <NUM> or the server <NUM>.

The communication unit <NUM> transmits and receives data by including a communication module such as near field wireless communication, such as Zigbee and Bluetooth, WiFi, Wibro, etc..

The communication unit <NUM> can receive a charging stand return signal or a guide signal for charging stand docking while communicating with the charging stand <NUM>. The mobile robot <NUM> searches out the charging stand on the basis of a signal that is received through the communication unit <NUM> and docks with the charging stand.

Meanwhile, the terminal <NUM> is a device that can connect with a network by being equipped with a communication module and in which a program for controlling the mobile robot or an application for controlling the mobile robot is installed, and devices such as a computer, a laptop, a smartphone, a PDA, a tablet PC, etc. may be used. Further, a wearable device such as a smart watch, etc. may be used as the terminal.

The running unit <NUM> includes at least one driving motor such that the mobile robot runs in accordance with a control instruction of the running control unit <NUM>. The running unit <NUM>, as described above, may include a left wheel driving motor that rotates a left wheel <NUM> and a right wheel driving motor that rotates a right wheel 36R.

The cleaning unit <NUM> makes a state in which dust or foreign substances around the mobile robot are easily suctioned by operating brushes, and suctions dust or foreign substances by operating a suction device. The cleaning unit <NUM> controls operation of the suction fan provided in the suction unit <NUM> that suctions foreign substances such as dust, waste, etc. such that dust is put into the foreign substance collection container through the suction port.

Further, the suction unit <NUM> may further include a damp cloth cleaning unit (not shown) that is installed at the rear of the bottom of the main body and wipes a floor surface with a damp cloth in contact with the floor surface, and a water tank that supplies water to the damp cloth cleaning unit. The cleaning unit <NUM> may be equipped with a cleaning tool. For example, a damp cloth pad may be mounted on the damp cloth clean unit and may clean a floor surface. The cleaning unit <NUM> may further include a separate driving unit that transmits a rotation force to the damp cloth pad of the damp cloth clean unit.

The battery (not shown) supplies power not only for the driving motor, but for the general operation of the mobile robot <NUM>. When the battery is fully discharged, the mobile robot <NUM> can run to return to the charging stand <NUM> for charging, and the mobile robot <NUM> can search for the location of the charging stand by itself during this return running. The charging stand <NUM> may include a signal transmitter (not shown0 that transmits a predetermined return signal. The return signal may be an ultrasonic wave signal or an infrared signal, but is not necessarily limited thereto.

The obstacle sensing unit <NUM> emits a predetermined shape of pattern and obtains an image of the emitted pattern. The obstacle sensing unit <NUM> may include at least one pattern emitter (not shown) and a pattern obtainer. Depending on cases, the imaging unit <NUM> may operate as the patter obtainer.

Further, the obstacle sensing unit <NUM> can sense the locations and distances of obstacles positioned in the running direction by including an ultrasonic wave sensor, a laser sensor, and an infrared sensor. Further, the obstacle sensing unit <NUM> can sense obstacles from images in the running direction. The sensor unit and imaging unit may be included in the obstacle sensing unit.

The sensor unit <NUM> senses obstacles by including a plurality of sensors. The sensor unit <NUM> senses obstacles at the front, that is, in the running direction using at least one of a laser, an ultrasonic wave, and infrared light.

Further, the sensor unit <NUM> may further include a step sensing sensor that senses whether a step exists on the floor in a running section. When receiving a signal transmitted and reflected, the sensor unit <NUM> inputs information about whether an obstacle exists or the distance to an obstacle to the control unit <NUM> as an obstacle sensing signal.

The sensor unit <NUM> senses the inclination of the main body by including at least one inclination sensor. When the main body inclines forward, rearward, left, and right directions, the inclination sensor calculates the inclination direction and angle. A tilt sensor, an acceleration sensor, etc. may be used as the inclination sensor, and when it is an acceleration sensor, any of a gyro type, an inertia type, and a silicon semiconductor type can be applied.

Further, the sensor unit <NUM> can sense an operation state and whether there is a problem or not through a sensor installed in the mobile robot <NUM>.

The obstacle sensing unit <NUM> may include a pattern emitter, a light source, and an Optical Pattern Projection Element (OPPE) that creates a predetermined pattern by transmitting light emitted from the light source. The light source may be a Laser Diode (LD), a Light Emitting Diode (LED), or the like. A laser beam is excellent in the characteristics of monocolor, straightness, and connection in comparison to other light sources, so it can measure a precise distance. In particularly, infrared light or visible light generates a large difference in precision of distance measurement, depending on the color, the material, etc. of an object, so a laser diode is preferable as a light source. The OPPE may include a lens, and a Diffractive optical element (DOE). Various patterns of light can be emitted in accordance with the configuration of the OPPE provided in each pattern emitter.

The pattern obtainer <NUM> can obtain an image of the front of the main body or an image of a ceiling. In particular, pattern light is shown in an image obtained by the pattern obtainer <NUM> (hereafter, referred to as an obtained image), and hereafter, the phase of the pattern light shown in an obtained image is referred as a light pattern and this is actually a phase of pattern light traveling into a space and formed on an image sensor. When a pattern emitter is not provided, the pattern obtainer obtains an image not including pattern light at the front of the main body.

The pattern obtainer may include a camera that converts the phase of an object into an electrical signal and then converts and store the electrical signal into a digital signal in a memory element. The camera may include at least one optical lens, an image sensor (e.g., a CMOS image sensor) including several photodiodes (e.g., pixels) in which images are formed by light that has passed through the optical lens, and a digital signal processor (DSP) that forms an image on the basis of signals output from the photodiodes. The digital signal processor can generate not only still images, but also moving images composed of frames composed of still images.

An image sensor is a device that converts an optical image into an electrical signal and is configured as a chip in which several photo diodes are integrated, and pixels may be exemplified as the photo diodes. Electrical charges are accumulated in each pixel by an image formed on a chip by light passing a lens, and the electrical charges accumulated in the pixels are converted into an electrical signal (e.g., voltage). A Charge Coupled Device (CCD), a Complementary Metal Oxide Semiconductor (CMOS), etc. are well known as image sensors.

The obstacle sensing unit <NUM> senses an obstacle in accordance with the shape of a pattern by analyzing the pattern by obtaining an image and the sensor unit <NUM> senses an obstacle positioned at a sensing distance of each sensor through provided sensors.

The imaging unit <NUM> continuously takes images when the mobile robot operates. Further, the imaging unit <NUM> can take images in the unit of a predetermined cycle or a predetermined distance. The imaging unit <NUM> can take an image when an obstacle is sensed by the obstacle sensing unit <NUM>, and can take an image even in a moving or cleaning state when an obstacle is not sensed.

The imaging unit <NUM> can set an imaging cycle in accordance with the moving speed of the mobile robot. Further, the imaging unit <NUM> can set an imaging cycle in consideration of the sensing distance of the sensor unit and the moving speed of the mobile robot.

The imaging unit <NUM> not only can obtain an image of the front in the running direction, but can image a ceiling shape in the upward direction.

The imaging unit <NUM> stores images that are taken while the main body runs into the data unit <NUM> as image data <NUM>.

The obstacle sensing unit <NUM> inputs information about the location or movement of sensed obstacles into the control unit <NUM>. The sensor unit <NUM> can input a sensing signal of an obstacle sensed by a provided sensor into the control unit. The imaging unit <NUM> inputs a taken image into the control unit.

The control unit <NUM> controls the running unit <NUM> such that the mobile robot runs within a predetermined section of a running section.

The control unit <NUM> sets an operation mode of the mobile robot by processing data that are input by operation of the operation unit <NUM>, outputs an operation state through the output unit <NUM>, and outputs a warning sound, an effect sound, and voice guidance according to an operation state, an error state, or sensing of an obstacle through a speaker.

The control unit <NUM> creates a map about a running region on the basis of an image obtained from the imaging unit <NUM> or obstacle information sensed by the obstacle sensing unit <NUM>. The control unit <NUM> creates a map on the basis of obstacle information while running in a region, that is, may create a map by determining a running region from an image of the imaging unit.

The control unit <NUM> recognizes an obstacle that is sensed by the imaging unit <NUM> or the obstacle sensing unit <NUM>, and controls the running unit by correspondingly performing a specific operation or changing the route. Further, the control unit, if necessary, can output a predetermined effect sound or warning sound through the output unit and can control the imaging unit to take images.

The control unit <NUM> controls the running unit <NUM> and the cleaning unit <NUM> while running to suction dust or foreign substances around the mobile robot, so cleaning of the running section is performed. Accordingly, the cleaning unit <NUM> makes a state in which dust or foreign substances around the mobile robot are easily suctioned by operating brushes, and suctions dust or foreign substances by operating a suction device. The cleaning unit is controlled to perform cleaning by suction foreign substances during running.

The control unit <NUM> determines the time to return to the charging stand by checking the charging capacity of the battery. When the charging capacity reaches a predetermined value, the control unit <NUM> stops the operation that is being performed, and starts to search for the charging stand to return to the charging stand. The control unit <NUM> can output an alarm about the charging capacity of the battery and an alarm about returning to the charging stand. Further, when a signal transmitted from the charging stand is received through the communication unit <NUM>, the control unit <NUM> can return to the charging stand.

The control unit <NUM> controls signal transmission cycles so that the signals of a plurality of sensors using signals of the same wavelength band can be discriminated.

The control unit <NUM> controls signal transmission cycles for the sensor unit, the obstacle sensing unit, and the charging stand. Further, when it is impossible to control a docking signal of the charging stand, the control unit <NUM> correspondingly changes the cycles of the sensors provided in the main body.

The control unit <NUM> discriminates signals by determining whether received signals are signals that are received in accordance with designated cycles.

When interference of signal is generated and when mis-sensing of a sensor is generated, the control unit <NUM> temporarily stops the operation of some sensors so that signals of other sensors can be received.

Accordingly, the mobile robot can prevent signal interference by changing the signal transmission cycles.

The control unit <NUM> includes an obstacle recognizer <NUM>, a map creator <NUM>, and a running controller <NUM>.

In an initial operation or when a map about a region is not stored, the map creator <NUM> creates a map about a region on the basis of obstacle information while running in the region. Further, the map creator <NUM> updates the created map on the basis of obstacle information that is obtained during running.

Further, the map creator <NUM> creates a map by determining the shape of a region by analyzing images that are obtained during running. The map creator <NUM> extracts a characteristic point by analyzing images and determines the shape of a region from the extracted characteristic.

The map creator <NUM> can determine the shape of a region by arranging a plurality of images or videos that is taken through the imaging unit in accordance with a location change of the mobile robot or the flow of time and matching the images or videos to locations.

Further, the map creator <NUM> can recognize from the characteristic extracted from an image. The map creator <NUM> can determine the location of a door on the basis of connection relationship of characteristics, and accordingly, can create a map composed of a plurality of regions by separating the boundaries of the regions.

The map creator <NUM> forms reference lines by connecting and separating extracted characteristics, and finally determines the shape of regions on the basis of the characteristics.

The obstacle recognizer <NUM> determines obstacles through data that are input from the imaging unit <NUM> or the obstacle sensing unit <NUM>, and the map creator <NUM> creates a map about a running section and puts information about sensed obstacles into the map.

The obstacle recognizer <NUM> determines obstacles by analyzing data that are input from the obstacle sensing unit <NUM>. The obstacle recognizer <NUM> calculates the direction of an obstacle or the distance to an obstacle in accordance with a sensing signal of the obstacle sensing unit, for example, a signal such as an ultrasonic wave or laser. When using an ultrasonic wave or infrared signal, there is a difference in the shape of received ultrasonic waves or in the time at which ultrasonic waves are received in accordance with the distances from obstacles or the locations of obstacles, the obstacle recognizer <NUM> determines obstacles on the basis of the differences.

The obstacle recognizer <NUM> extracts a pattern by analyzing an obtained image including the patter and determines obstacles by analyzing the shape of the pattern.

Further, the obstacle recognizer <NUM> can recognize a human body. The obstacle recognizer <NUM> senses a human body by analyzing data that are input through the obstacle sensing unit <NUM> or the imaging unit <NUM>, and determines whether the human body is a specific user.

The obstacle recognizer <NUM> can determine whether a human body is a previously registered user when a human body is sensed by storing data of registered users, for example, images of users and characters of the shapes of users as data.

The obstacle recognizer <NUM> extracts characteristics of an obstacle by analyzing image data, and determines an obstacle and the location on the basis of the shape (form), size, and color of the obstacle.

The obstacle recognizer <NUM> can determine the kind of an obstacle by extracting characteristics of the obstacle on the basis of previously stored obstacle data except for the background of an image from image data. The obstacle data <NUM> are updated by new obstacle data that are received from a server. The mobile robot <NUM> can store obstacle data about sensed obstacles and receive data about the kinds of obstacles from the server for other data. Further, the obstacle recognizer <NUM> stores information of a recognized obstacle into the obstacle data and transmits recognizable image data to the server (not shown) through the communication unit <NUM> such that the kind of the obstacle is determined. The communication unit <NUM> transmits at least one image datum to the server.

The running controller <NUM> controls the running unit <NUM> to pass through an obstacle or avoid an obstacle by changing the moving direction or running route in response to obstacle information.

The running controller <NUM> independently controls operation of the left wheel driving motor and the right wheel driving motor by controlling the running unit <NUM> such that the main body <NUM> runs straight or turns. The running controller <NUM> controls the running unit <NUM> and the cleaning unit <NUM> in accordance with a cleaning instruction such that the main body <NUM> performs cleaning by suctioning foreign substances while running in a cleaning region.

The running controller <NUM> controls the running unit <NUM> to move to a set region or such that the main body moves in the set region on the basis of a map created by the map creator <NUM>. Further, the running controller <NUM> controls the running unit to perform a predetermined operation or change the running route in response to an obstacle in accordance with a sensing signal of the obstacle sensing unit <NUM>.

The running controller <NUM> controls the running unit to perform at least one of avoiding, approaching, setting of an approach distance, stop, decelerating, accelerating, backward running, U turn, and changing of the running direction in response to sensed obstacles.

Further, the running controller <NUM> can output an error and output a predetermined warning sound or voice guidance, if necessary.

<FIG> is a view that is referred to describe signal interference of a mobile robot according to an embodiment of the present disclosure and a charging stand.

As shown in <FIG>, the mobile robot <NUM> docks with the charging stand and charges the battery by being supplied with a charging current.

The charging stand <NUM> transmits a docking signal SD that induces docking of the mobile robot <NUM>.

When charging is required and a docking signal SD transmitted from the charging stand <NUM> is received, the mobile robot <NUM> returns to the charging stand <NUM> and attempts to dock.

The charging stand <NUM> outputs a docking signal through a signal transmitter <NUM>. An IR signal may be used as the docking signal.

The mobile robot <NUM> includes a plurality of sensors <NUM> provided on the front surface of the main body <NUM> other than the obstacle sensing unit <NUM>. The plurality of sensors may be included in the sensor unit <NUM>.

The plurality of sensors is installed on the front surface of the main body <NUM> toward a front and upper direction and transmits sensing signals ST. An IR signal may be used as the sensing signal ST. Time of Flight (TOF) may be used as the plurality of sensors.

When an IR signal is used for both the docking signal SD of the charging stand and the sensing signal ST of the sensor unit, signal interference may be generated. In particular, when the mobile robot attempts to dock with the charging stand, the main body faces the charging stand, so signal interference is generated. For example, misoperation may be generated by recognizing a docking signal as a sensing signal.

Other than when attempting to dock, when the mobile robot runs in a range that a docking signal reaches, the sensing signals of the sensors and the docking signal are signals of the same wavelength, so mutual interference may be generated.

Further, a sensing signal may be reflected by a side of the charging stand and then input to a docking signal receiving unit <NUM>. In this case, the docking signal is interfered with by the sensing signal, so docking may fail.

As described above, while running around the charging stand or attempting to dock, the mobile robot may recognize a docking signal as a sensing signal or may recognize a sensing signal as a docking signal. Further, when a sensing signal is reflected by a surrounding obstacle or wall and travels into the receiver of a sensor, mis-sensing may be generated.

An IR signal of a wavelength band of <NUM> may be used as the docking signal and the sensing signal. The wavelength band may be changed, and the present disclosure may be applied to prevent interference by discriminating a plurality of signals of the same wavelength band.

<FIG> is a view showing a sensing signal of a sensor for sensing obstacles of the mobile robot according to an embodiment of the present disclosure.

As shown in <FIG>, a plurality of sensors <NUM> is circumferentially arranged with regular intervals around the center of the front surface of the main body <NUM>.

A sensor hole is formed in the casing of the main body <NUM> and the sensors <NUM> are each mounted on a circuit board (PCB) positioned inside the sensor hole, so first to sixth sensors <NUM> to <NUM> can transmit predetermined sensing signals ST1 to ST6 through the sensor hole and can sense an obstacle in accordance with received signals.

The first to sixth sensors <NUM> to <NUM> are each mounted on a circuit board (not shown), and a transmitter and a receiver are provided on one circuit board. The sensors <NUM> transmit and receive signals of laser, ultrasonic wave, infrared, etc., and hereafter, transmitting an infrared signal is exemplified. TOF sensors may be used as the plurality of sensors <NUM>.

The circuit boards on which the first to sixth sensors are mounted, respectively, are connected to a main substrate (not shown) disposed at the center inside the main body <NUM>, and controls sensing signals of the first to sixth sensors and senses obstacles through received signals. The circuit boards on which the first to sixth sensors are mounted, respectively, are connected to each other through flexible connectors and are connected with the main substrate.

The main substrate has a control unit, supplies operation power to a plurality of circuit boards on which the first to sixth sensors <NUM> to <NUM> are mounted, and receives and applies sensing signals from the first to sixth sensors <NUM> to <NUM> to the control unit <NUM>. The control unit is composed of at least one process.

The first to sixth sensors <NUM> to <NUM> share a clock signal and a communication line and are connected to individual power lines, so they can be supplied with operation power. Signal values of the sensors can be applied to the control unit through the power lines. The control unit <NUM> receives sensing signals of the sensors through variation of voltage or current of the power lines.

<FIG> is a view showing a docking signal of a charge cradle according to an embodiment of the present disclosure.

As shown in <FIG>, the charging stand <NUM> includes a charging terminal <NUM> and the signal transmitter <NUM>. Further, the charging stand may include a proximity sensor that senses approach of the mobile robot.

The signal transmitter <NUM> is installed on a side of the charging stand and transmits a docking signal SD in a direction in which the main body of the mobile robot <NUM> docks.

The signal transmitter <NUM> transmits a docking signal SD so that the mobile robot approaches the charging stand and the charging terminal can be electrically connected.

An infrared signal may be applied as the docking signal SD.

<FIG> is a view that is referred to describe a signal interference phenomenon of a sensing signal of the mobile robot according to an embodiment of the present disclosure and a docking signal.

As shown in <FIG>, since signals of the same wavelength are used, the docking signal SD and the sensing signal ST may overlap.

When the signals overlap, the control unit has difficulty in discriminate the docking signal and the sensing signal, so it is impossible to determine whether an obstacle is sensed and to return to the charging stand when it is needed.

Accordingly, the control unit <NUM> controls signal transmission cycles of the first to sixth sensors <NUM> to <NUM>.

As in <FIG>, the charging stand outputs a docking signal with a cycle of about <NUM>.

The control unit <NUM> controls the signal transmission cycles of the first to sixth sensors <NUM> to <NUM> different from the signal transmission cycle of the docking signal for discrimination from the docking signal.

As shown in <FIG>, the control unit <NUM> can set signal transmission cycles for a plurality of sensors different from the signal transmission cycle of the docking signal of the charging stand. For example, the control unit <NUM> controls sensing signals to be transmitted with a cycle of <NUM>.

The control unit controls signal transmission cycles of a plurality of sensors using synchronization signals and power lines connected with the first to sixth sensors.

The control unit can minimize interference of signals by differently setting signal transmission cycles of the docking signal and the sensing signals.

When a sensing signal or a docking signal is input, the control unit <NUM> discriminates signals by determining whether the signal is a signal corresponding to a designated cycle.

When a docking signal is received before reaching the signal transmission cycle of the docking signal or when a sensing signal is received before reaching the signal transmission cycle of the sensing signal, the control unit can determine that noise is generated. When noise is generated, the control unit determines that a signal is sensed wrong.

When a signal is input at time other than a designated cycle, the control unit <NUM> can determine mis-sensing of a signal.

When mis-sensing of a signal is generated, the control unit <NUM> can control the sensors to stop operating for a predetermined time. While the sensors stop operating and do not transmit sensing signals, signal interference of sensing signals and a docking signal is not generated, so the docking signal can be normally received.

Further, the control unit <NUM> can reset the signal transmission cycles of the sensors by temporarily stopping operation of the sensors. Depending on cases, the control unit <NUM> can change the signal transmission cycles of the sensors.

Accordingly, the mobile robot <NUM> can prevent the mis-sensing phenomenon when a docking signal is input as a sensing signal or a sensing signal is input as a docking signal.

<FIG> is a flowchart showing a control method for signal processing of the mobile robot according to an embodiment of the present disclosure.

As shown in <FIG>, the mobile robot <NUM> performs cleaning and operates while moving to a designated location or running in a set region in accordance with setting.

The control unit <NUM> controls a plurality of sensors to transmit sensing signals at a first time that is a designated control cycle (S320). Accordingly, the first to sixth sensors transmit sensing signals and recognize an obstacle through incident reception signals. The first time may be set in response to the transmission cycles of sensing signals.

When a control cycle is reached, the control unit <NUM> determines whether the main body is cleaning or is moved to a specific location (S330).

When being moving, even if the docking signal is received, the mobile robot <NUM> ignores the docking signal and controls the first to sixth sensors to transmit sensing signals and sense obstacles during running (S370).

The control unit <NUM> controls the first to sixth sensors to transmit sensing signals at every control cycle. The obstacle sensing unit can sense obstacles using pattern light separately from the first to sixth sensors of the sensor unit.

When the mobile robot is cleaning or moving to a destination and when the charging current of the battery is sufficient, the control unit <NUM> is not required to attempt docking, so it is possible to operate in accordance with sensing signals without considering a docking signal. The control unit <NUM> controls the running unit such that the main body moves by setting a running route in accordance with sensed obstacles by ignoring a docking signal even if the docking signal is received during cleaning or moving.

When the main body is not cleaning or moving, that is, when the main body returns to the charging stand for charging or stands by without a set operation, the control unit <NUM> determines whether a sensing signal is sensed wrong (S340).

When a sensing signal and the docking signal are simultaneously sensed and overlap each other, the control unit <NUM> determined that it is mis-sensing of a signal. Further, when a sensing signal is received to the docking signal receiving unit <NUM>, when a sensing signal that is not a docking signal is recognized as a docking signal, and when the docking signal is sensed wrong as a sensing signal, the control unit <NUM> determines that a sensing signal is sensed wrong.

The control unit <NUM> can determine whether a signal is a sensing signal by comparing the pattern of a sensed signal, and can determined whether a signal is sensed wrong by determining whether it corresponds to the signal transmission cycles of a sensing signal and a docking signal.

When a docking signal is received before reaching the signal transmission cycle of the docking signal or when a sensing signal is received before reaching the signal transmission cycle of the sensing signal, the control unit can determine that noise is generated. When noise is generated, the control unit determines that a signal is mis-sensed.

When a sensing signal of an obstacle is sensed wrong, the control unit stops the first to sixth sensors <NUM> to <NUM> to stop operating for a second time (S350). The first to sixth sensors stand by without transmitting a sensing signal in accordance with a control instruction of the control unit.

The second time is set larger than the signal transmission cycles of sensing signals and it is preferable that the second time is set as time for which a sensing is not transmitted at least two times. The second time may be set as <NUM> to <NUM>. The second time may be set as <NUM>.

Since sensing signals of the first to sixth sensors are not transmitted, it is possible to prevent a sensing signal from being sensed wrong as a docking signal.

Meanwhile, when a control cycle is reached with a plurality of sensors stopping operation, whether a docking signal is received is determined (S360). When a docking signal is not received, it is possible to stand by until the next control cycle.

Further, when charging is required or a docking signal is received while attempting to dock, the control unit determines whether the docking signal is a normal signal.

When mis-sensing of an obstacle is not generated, the control unit <NUM> determines whether a received signal is a docking signal (S360).

When a docking signal is not received, sensing of an obstacle through sensing signals of the first sensor to sixth sensor is performed (S370). It is determined that the mobile robot <NUM> does not approach the charging stand, so it is possible to keep running to return to the charging stand while sensing obstacles.

When a docking signal is received while attempting to dock, the control unit <NUM> stops sensing of obstacles (S380). The control unit <NUM> controls the first to sixth sensors <NUM> to <NUM> to output a sensing signal one time and then controls the first to sixth sensors <NUM> to <NUM> to stop operating.

The control unit controls the first to sixth sensors to stop sensing obstacles in order to prevent signal interference during docking.

The first to sixth sensors transmit a sensing signal and then stand by without transmitting a sensing signal for a third time in accordance with a control instruction of the control unit. The third time may be set on the basis of time for which docking is attempted in accordance with a docking signal or time that is taken for docking. The third time may be set as about <NUM>.

The control unit <NUM> senses surrounding obstacles through sensing signals before docking with the charging stand. The control unit <NUM> can determine the distance from the charging stand through sensing signals.

The control unit controls the running unit in response to a docking signal (S390). Accordingly, the main body docks with the charging stand and is connected with the charging terminal, so a charging current is supplied.

Accordingly, the mobile robot differently sets the cycles of sensing signals and a docking signal and discriminates sensing signals and a docking signal in response to the cycles of the sensing signals and the operation state of the main body. When a signal is sensed wrong, it is possible to prevent mis-sensing of a signal by stopping sensing of obstacles.

Further, it is possible to prevent a docking signal is sensed wrong by controlling operation of sensing signals when docking with the charging stand.

<FIG> is a flowchart showing signal flow of the mobile robot according to an embodiment of the present disclosure and a charging stand.

As shown in <FIG>, when the first to sixth sensors <NUM> to <NUM> transmit sensing signals and the charging stand <NUM> transmits a docking signal, the control unit <NUM> senses an obstacle and attempts to dock in accordance with the received signals.

The first to sixth sensors <NUM> to <NUM> transmit sensing signals in accordance with the designated signal transmission cycle (S110 to S130).

The charging stand <NUM> transmits a docking signal in accordance with the designated signal transmission cycle (S180) (S230).

When sensing signals are reflected by an obstacle and received to the receivers of the sensors, respectively, the sensors input sensor values into the control unit <NUM>. The control unit <NUM> determines whether an obstacle is positioned in the running direction or the location of an obstacle in accordance with the input sensor values.

When a sensing signal is received even though a sensing signal is not transmitted from a sensor, the control unit <NUM> can determine that noise is generated by determining that a copy signal of the sensing signal or a docking signal is received.

Further, when sensing signals transmitted from the first to sixths sensors and a docking signal of the charging stand are received to the docking signal receiving unit <NUM>, the control unit <NUM> determines noise due to overlap of signals (S140).

When noise is generated (S150), the control unit <NUM> determined mis-sensing of a signal and applies a control instruction such that the first to sixth sensors stops sensing obstacles for the second time (S160).

The first to sixth sensors <NUM> to <NUM> stop operating and stand by for the second time in accordance with the control instruction (S170). The second time may be set as about <NUM>.

When a docking signal is received with the first to sixth sensors <NUM> to <NUM> stopped (S <NUM>), the control unit <NUM> transmits a control instruction for docking to the first to sixth sensors <NUM> to <NUM> (S190).

The first to sixth sensors <NUM> to <NUM> output sensing signals one time in accordance with the control instruction for docking (S200). The control unit can calculate the distance from the charging stand in accordance with the sensing signals.

The control unit <NUM> applies a control instruction such that the first to sixth sensors <NUM> to <NUM> stop operating for the third time (S210).

The first to sixth sensors <NUM> to <NUM> stand by without transmitting sensing signals for the third time. The third time may be set as about <NUM>.

Accordingly, the mobile robot can prevent interference of signals by determining noise and stopping transmission of signals from the sensors when signals overlap. Further, when docking with the charging stand, the mobile robot can dock with the charging stand in accordance with a docking signal by stopping the sensors.

Claim 1:
A mobile robot (<NUM>) comprising:
a main body (<NUM>) configured for running in a region;
a sensor unit disposed on a front of the main body and configured for sensing an obstacle located at a predetermined distance from the main body by transmitting a sensing signal;
a docking signal receiving unit configured for receiving a docking signal that is transmitted from a charging stand (<NUM>);
a running unit (<NUM>) configured for controlling running of the main body; and
a control unit (<NUM>) configured for determining the location of the obstacle in response to the sensing signal, for controlling running in response to the obstacle, and for controlling the running unit to dock with the charging stand in accordance with the docking signal if charging is required,
wherein the control unit is configured to control the sensor unit to transmit a sensing signal with a cycle different from a signal transmission cycle of the docking signal, characterized in that the control unit is further configured to determine that a signal is sensed wrong and to stop operation of the sensor unit for a predetermined time when noise is generated due to overlap of the docking signal and the sensing signal.