Patent ID: 12213402

DETAILED DESCRIPTION

The disclosed embodiments will now be described more fully hereinafter with reference to the accompanying drawings, in which certain embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided by way of example so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Like numbers refer to like elements throughout.

In one of its aspects, the disclosure presented herein concerns a robotic work tool system for defining a stay-out area within a work area.FIG.1illustrates a schematic overview of a robotic work tool100in such a work area150. As will be appreciated, the schematic view is not to scale. If the work area150is a lawn and the robotic work tool100is a robotic lawn mower, the work area150is the area to be mowed by the robotic work tool100. As seen inFIG.1, the work area150is surrounded by a work area perimeter105. The work area perimeter105sets the boundaries for the work area150, i.e. defines the boundaries for the work area150. The robotic work tool100is intended to operate within the work area150and remain within this area due to the work area perimeter105. The robotic work tool100will not cross this perimeter105and only operate within the enclosed area, i.e. the work area150.

As further illustrated inFIG.1, the work area150further comprises two stay-out areas120. The stay-out areas120withinFIG.1are illustrated as a flowerbed and as a bush. A stay-out area120is an area that is to be excluded from the work area150in which the robotic work tool100operates. A stay-out area120is located within the work area150. The stay-out area120may be fully enclosed by the work area150. By defining stay-out areas120, it may be ensured that the robotic work tool100will not operate within these areas. This may be used to protect, for example, flowerbeds and bushes, or to prevent the robotic work tool100to travel into restricted areas such as ponds and areas that may damage the robotic work tool100. Thus, stay-out areas120are areas within the work area150that for different reasons should not be entered by a robotic work tool100.

With reference toFIG.2, a first embodiment according to the first aspect will now be described.FIG.2shows a schematic view of a robotic work tool system200. As will be appreciated, the schematic view is not to scale. The robotic work tool system200comprises at least one boundary definition unit130and at least one controller110,210. The robotic work tool system200will mainly be described in general terms of a robotic work tool system200for defining a stay-out area120within a work area150, such as a lawn. However, it should be understood that the robotic work tool system200described herein may be implemented together with any type of autonomous machine that may perform a desired activity within a desired work area. Examples of such types of autonomous machines include, without limitation, cleaning robotic work tools, polishing work tools, repair work tools, surface-processing work tools (for indoors and/or outdoors), and/or demolition work tool or the like.

The boundary definition unit130of the robotic work tool system200may be, for example, the robotic work tool100, which is subsequently intended to operate within the work area150. Alternatively, the at least one boundary definition unit130may be a device used for defining the stay-out area120, which is a device separated from the robotic work tool100and which is not intended to subsequently operate within the work area150.

The boundary definition unit130illustrated inFIG.2is exemplified as a robotic work tool100, but it may be appreciated that it may be exemplified in a variety of ways. The robotic work tool100may be, for example, a robotic lawnmower.FIG.2shows a boundary definition unit130having a body and a plurality of wheels160. The wheels160of the boundary definition unit130are to illustrate that the boundary definition unit130is movable. In other embodiments, the wheels160may be embodied as, for example, caterpillar threads. In still other embodiments, the boundary definition unit130itself is not movable, but may be moved, for example, by a user. This may be the case, for example, when the boundary definition unit130is embodied as a smartphone.

As also illustrated inFIG.2, the boundary definition unit130comprises at least one position unit175configured to receive position data or a positioning signal. The position unit175may comprise a satellite signal receiver, which may be a Global Navigation Satellite System (GNSS) satellite signal receiver. An example of such a system is Global Positioning System (GPS). The position unit175may be configured to use, for example, Real-Time Kinematic, RTK, positioning. In advantageous embodiments, the at least one position unit175may use RTK-GNSS positioning. A RTK-GNSS system is based on satellite communication. The at least one position unit175may be connected to the at least one controller110,210of the robotic work tool system200for enabling the controller110,210to determine current positions for the boundary definition unit130.

In some embodiments, the at least one position unit175may further comprise a deduced reckoning navigation sensor for providing signals for deduced reckoning navigation, also referred to as dead reckoning. Examples of such deduced reckoning navigation sensors are odometers, inertial measurement units (IMUs) and compasses. These may comprise, for example, wheel tick counters, accelerometers and gyroscopes. Additionally, visual odometry may be used to strengthen the dead reckoning accuracy further. Thus, in some embodiments, the at least one controller110,210may be configured to use dead reckoning to extrapolate the position data if the quality, or the strength, of the position data received from the satellite signal receiver goes below an acceptable level. The dead reckoning may then be based on the last known position received from the satellite signal receiver.

As may be appreciated, in some embodiments, the robotic work tool system200may comprise a plurality of boundary definition units130. The plurality of boundary definition units may be used to define stay-out areas120simultaneously. This may be used if the work area150, for example, is very large. The plurality of boundary definition units130may define, for example, stay-out areas120within different parts of the work area150. Thereafter, each stay-out area120, defined by the plurality of boundary definition units120, may be added to the common work area150, such that one work area150with the defined stay-out areas120is created. By using a plurality of boundary definition units130, the defining of the stay-out areas120may be performed more quickly.

As previously described, the robotic work tool system200comprises at least one controller110,210. The at least one controller110,210may be, for example, a controller110located in the boundary definition unit130. In such embodiments, the boundary definition unit130corresponds to the robotic work tool system200. According to another example, the at least one controller110,210may be located in a device230that is separated from the boundary definition unit130. Embodiments with a remote controller210located in a device230remote from the boundary definition unit130may be advantageous when several boundary definition units130are operating to define stay-out areas120within a work area150. The remote controller210may then add all defined stay-out areas120, which are based on data received from the plurality of boundary definition units130, into one common work area150. When the at least one controller210is located in another device230than in the boundary definition unit130, the separate device230is communicatively coupled to the boundary definition unit130. They may be communicatively coupled to each other by a wireless communication interface. Additionally, or alternatively, the wireless communication interface may be used to communicate with other devices, such as servers, personal computers or smartphones, charging stations, remote controls, other robotic work tools or any remote device, which comprises a wireless communication interface and a controller. Examples of such wireless communication are Bluetooth®, Global System Mobile (GSM), Long Term Evolution (LTE) and 5G or New Radio (NR), to name a few.

In one embodiment, the at least one controller110,210is embodied as software, e.g. remotely in a cloud-based solution. In another embodiment, the at least one controller110,210may be embodied as a hardware controller. The at least one controller110,210may be implemented using any suitable, publicly available processor or Programmable Logic Circuit (PLC). The at least one controller110,210may be implemented using instructions that enable hardware functionality, for example, by using executable computer program instructions in a general-purpose or special-purpose processor that may be stored on a computer readable storage medium (disk, memory etc.) to be executed by such a processor. The controller110,210may be configured to read instructions from a memory140,240and execute these instructions to control the operation of the at least one boundary definition unit130including, but not being limited to, the propulsion of the at least one boundary definition unit130including. The memory140,240may be implemented using any commonly known technology for computer-readable memories such as ROM, RAM, SRAM, DRAM, FLASH, DDR, SDRAM or some other memory technology.

The present disclosure is now going to be described with reference toFIGS.3aand3b.FIG.3aillustrates an example of a boundary definition unit130moving within an area comprising a stay-out area120. As will be appreciated, the schematic view is not to scale. The boundary definition unit130inFIG.3ais approaching a flowerbed. The flowerbed exemplifies a stay-out area120, i.e. an area that is to be excluded from a work area150. The aim of the present robotic work tool system200is to define the stay-out area120such that the robotic work tool100that is subsequently intended to operate within the work area150does not drive into the flowerbed, i.e. the stay-out area120. The present robotic work tool system200defines the boundaries of the stay-out area120such that the robotic work tool10does not cross the boundaries surrounding the flowerbed. As the stay-out area120keeps the robotic work tool100away from areas that the robotic work tool100should not enter, it is important that the stay-out area120is accurately defined. If the stay-out area120is not correctly defined, the robotic work tool100may still enter into parts of the stay-out area120. The present disclosure provide a robotic work tool system200that defines a stay-out area120in an easy and accurate way.

According to the present disclosure, the at least one controller110,210is configured to receive a stay-out area definition trigger signal. The stay-out area definition trigger signal is a signal that indicates that the boundary definition unit130has approached a stay-out area to be defined, i.e. the stay-out area which should be defined by the robotic work tool system200. Accordingly, the stay-out area definition trigger signal is a signal that starts, or triggers, the process of defining the stay-out area120. Based on the received stay-out area definition trigger signal, the at least one controller110,210is configured to receive position data from the at least one position unit175. The position data indicates the present position of the boundary definition unit130. The at least one controller110,210is thereafter configured to define the stay-out area120as an area centered at an offset310from the received position data. This is illustrated inFIG.3b. Accordingly, when the boundary definition unit130has approached the flowerbed, the at least one controller110,210is configured to define the stay-out area120as an area with a center that is located a certain offset310from the previously received position.

By introducing the above proposed robotic work tool system200, the previously described disadvantages are eliminated or at least reduced. With the provided robotic work tool system200, it is possible to define a stay-out area120within a work area150in a time efficient, but still accurate, manner. The boundary definition unit130does not have to define a stay-out area120by travelling around the area. Instead, the boundary definition unit130just have to approach the stay-out area120in order for it to be defined by the robotic work tool system200. A signal which indicates that a stay-out area120should be defined, i.e. a stay-out area definition trigger signal, is received and then the stay-out area120is defined based on the position of the boundary definition unit130. Thus, a simplified process for defining stay-out areas120is achieved and the overall time for defining a work area150with at least one stay-out area120may be reduced.

The geographical coordinates defining the boundary of the stay-out area120may be stored in a memory140,240and/or included in a digital (virtual) map of the work area150. Thus, when a robotic work tool100subsequently operates within the work area150, the robotic work tool100may use a satellite navigation device and/or a deduced reckoning navigation sensor to remain outside the stay-out areas120, but within the work area150. This may be achieved by comparing the successive determined positions of the robotic work tool100against the set of geographical coordinates defining the boundary of the work area150and the boundary of the stay-out areas120.

In some embodiments, the at least one controller110,210may further be configured to position an outer perimeter of the stay-out area120at the position of the boundary definition unit130. The outer perimeter corresponds to the outer edge of the stay-out area120, regardless of the shape of this area. Thus, when looking atFIG.3b, this means that the perimeter of the flowerbed will be defined to be located at the boundary definition unit's130position, and the center of the stay-out area120will be defined to be located at the offset310from the received position data. This may be advantageous in work areas150where a plurality of stay-out areas120with the approximately same size is located. The position of the boundary definition unit130may be reflected by the position data received by the position unit175. In some embodiments, the position of the boundary definition unit130corresponds to the edge of the boundary definition unit130. InFIG.3b, the front edge of the boundary definition unit130corresponds to the position of the boundary definition unit130. However, it should be realized that in embodiments where the position unit175reflects positions with a very high accuracy, such as when RTK is utilized, the position of the position unit175would not be the same as the position of the boundary definition unit130. In these embodiments, the received position data may be used to reflect the position of the boundary definition unit130, even if it, unprocessed, does not exactly mirror the boundary definition unit's position.

The offset310from the received position data, which defines the center of the stay out area, may comprise an offset direction in some embodiments. The offset direction may be based on, for example, a heading of the boundary definition unit130. Alternatively, or additionally, the offset310may comprise an offset distance. For example, the offset distance may be set based on a size of the stay-out area120. Thus, by defining the offset by at least one of an offset distance and an offset direction, it may be possible to control the size, shape and position of the stay-out area120to be defined more accurately and it may be possible to adapt a stay-out area120to current conditions.

In some embodiments, the offset may be a predefined offset. Thus, as soon as the stay-out area definition trigger signal and the position data indicating the position of the boundary definition unit130are received, the stay-out area120is defined as an area centered at the predefined offset from the received position data. The predefined offset may comprise a predefined offset direction or a predefined offset distance or both a predefined offset direction and distance. Using a predefined offset may be advantageous when it is desirable that the stay-out areas120are defined quickly. Furthermore, it may be advantageous when a plurality of stay-out areas120of similar sizes is located within the work area150.

The robotic work tool system200may further comprise a user interface250, as illustrated inFIG.2. The user interface250may for example be a touch user interface. The user interface250may be in an apparatus230separated from the boundary definition unit130, but it may be appreciated that the user interface250may be located at the boundary definition unit130. The user interface250may be in the same apparatus as the at least one controller110,210. However, in one embodiment the user interface250may be located in a device separate from the at least one controller110,210.

In some embodiments, when the boundary definition unit130for example is a smart phone, the user interface250, the at least one controller110and the position unit175may all be comprised in the smart phone and thus, the robotic work tool system200may correspond to the smart phone.

The user interface250may be configured to display the defined stay-out area120. It may be displayed to a user/operator who is operating the user interface250. In one embodiment, the defined stay-out area120may be displayed in the user interface250associated with the work area150.

The user interface250may be configured to receive user input from a user during the user's operation and interaction with said user interface250. The user interface250may be configured to receive input related to the stay-out area120.

In one embodiment, the at least one controller110,210may further be configured to define the stay-out area120based on the received user input. For example, the offset, with which the stay-out area120is defined to be centered from the received position data, may be adjustable via the user interface250. The offset may be adjustable such that a predetermined offset may be set via the user interface250. Alternatively, the offset may be adjustable in such way that it may be set via the user interface250once the at least one controller110,210receives the stay-out area definition trigger signal and the position data indicating the position of the boundary definition unit130.

In embodiments where said offset comprises an offset distance, the offset distance may be adjustable via the user interface250. The received user input may determine the offset distance. Additionally, or alternately, if said offset comprises an offset direction, the offset direction may be adjustable via the user interface250and the received user input may determine the offset direction.

In one embodiment, the received user input may determine a shape of the stay-out area120. The shape of the stay-out area120may be selectable from a set of predefined shapes in the user interface250. For example, the shape of the stay-out area120may be at least one from the group comprising: a circle, a square and a rectangle. The shape of the stay-out area120may be set such that it is automatically set to a certain shape once a stay-out area definition trigger signal is received. Alternatively, the shape of the stay-out area120may be selected via the user interface250once the stay-out area definition trigger signal is received. In such embodiments, it may be selected which of the predetermined shapes that best matches the stay-out area120that is to be defined. This may be preferable if many differently shaped stay-out areas120are located within the work area150.

In one embodiment, an orientation of the shape of the stay-out area120may be adjustable via the user interface250. The received user input may then determine the orientation of the shape of the stay-out area120. Additionally, or alternatively, an aspect ratio of the shape of the stay-out area120may be adjustable via the user interface250. The received user input may then determine the aspect ratio of the shape of the stay-out area120and thus a size of the stay-out area120may be determined. For example, if the stay-out area120may have the shape of a rectangle, the aspect ratio may determine the width of the rectangle.

By providing a user interface250as described above, a fast and simple adaptation of a stay-out area120may be achieved.

As previously described, the robotic work tool system200starts defining a stay-out area120when a stay-out area definition trigger signal is received. The stay-out area definition trigger signal may be based on different types of input. In one embodiment, the stay-out area definition trigger signal may be based on input received via the user interface250. Thus, a user may indicate via the user interface250that the boundary definition unit130is located at a stay-out area120and that a stay-out area120should be defined. According to this embodiment, the boundary definition unit130may be driven to a stay-out area120, and then the stay-out area definition trigger signal may be initiated via the user interface250. This will subsequently initiate the process of defining the stay-out area120.

In one embodiment, the stay-out area definition trigger signal may be based on received sensor data. In this embodiment, the boundary definition unit130further comprises a sensor unit180configured to receive sensor data indicating that an object is located in front of the boundary definition unit130. Thus, the boundary definition unit130may detect an object in front of the boundary definition unit130and this may trigger the stay-out area definition trigger signal such that a stay-out area120is defined. The sensor unit180may be configured to obtain sensed input data. The obtained sensed input data may be, without limitations, photo data, odometric data, position data, direction data etc. The at least one sensor unit180may be, for example, at least one of a camera, a radar sensor, a lidar sensor, an ultrasonic sensor, a compass and, a position unit.

In still one embodiment, the stay-out area definition trigger signal may be based on a signal indicating that the boundary definition unit130is not moving. Thus, when the boundary definition unit130does not move, this is an indication that the boundary definition unit130is located at a stay-out area120and that a stay-out area120should be defined. For example, the signal indicating that the boundary definition unit130is not moving may be received from at least one from the group comprising: a motor, an odometer and an accelerometer.

It may be appreciated that in still one embodiment the stay-out area definition trigger signal may be based on a combination of different types of input. Without limitations, the stay-out area definition trigger signal may be based on, for example, input received both via received sensor data and via the user interface250. In such embodiment, the stay-out area definition trigger signal may not be generated, for example, until the sensor data indicates that the boundary definition unit130is located at a stay-out area120and this has been confirmed by input data received via the user interface250. Several other combinations of different types of input are possible, and the described embodiment is just to illustrate an example.

Accordingly, the present robotic work tool system200provides a time efficient and accurate solution for defining a stay-out area120. The robotic work tool system200makes it possible to define a stay-out area120easily, without having to drive a boundary definition unit130around the stay-out area120to be defined. It will be enough for the boundary definition unit130to approach the stay-out area120in order to define it. Furthermore, as the stay-out area120will be defined as an area centered at an offset from received position data, the location of the stay-out area120will be accurately reflected and thus, creating the stay-out areas120at the locations where they should be. Accordingly, with the proposed system, a more accurately defined work area, with correctly defined stay-out areas120will be created.

In some embodiments, the boundary definition unit130is a robotic work tool100. In one advantageous embodiment, the robotic work tool100may be a robotic lawn mower.

According to a second aspect, there is provided a method implemented in the robotic work tool system200according to the first aspect. The method will be described with reference toFIG.4.

In one embodiment, the method400may be performed by a robotic work tool system200for defining a stay-out area120within a work area150. The stay-out area120is an area that is to be excluded from the work area150in which a robotic work tool100is subsequently intended to operate. As illustrated inFIG.4, the method400starts with step410of receiving a stay-out area definition trigger signal. The stay-out area definition trigger signal is a signal that indicates that a boundary definition unit130has approached the stay-out area to be defined. The method400further comprises the step420of receiving, based on the received stay-out area definition trigger signal, position data. The position data indicates the present position of the boundary definition unit130. Thereafter, the method400continues with step430of defining the stay-out area120as an area centered at an offset from the received position data.

With the proposed method400it may be possible to define a stay-out area120within a work area150in a time efficient, but still accurate way. By defining a stay-out area120based on a position of the boundary definition unit130when a stay-out area definition trigger signal is received, it is possible to define stay-out areas120without having to guide the boundary definition unit130around the area. Furthermore, as the stay-out area120is defined based on position data indicating the present position of the boundary definition unit130, the stay-out area may also be accurately defined.

In some embodiments, the method400further comprises positioning an outer perimeter of the stay-out area at the position of the boundary definition unit130.

In some embodiments, the method400comprises defining the stay-out area120based on received user input. By further defining the stay-out area120based on user input, the method400may be possible to influence the stay-out area120to be defined.

FIG.5shows a schematic view of a computer-readable medium as described in the above. The computer-readable medium500is in this embodiment a data disc500. In one embodiment, the data disc500is a magnetic data storage disc. The data disc500is configured to carry instructions510that when loaded into a controller, such as a processor, execute a method or procedure according to the embodiments disclosed above. The data disc500is arranged to be connected to or within and read by a reading device, for loading the instructions into the controller. One such example of a reading device in combination with one (or several) data disc(s)500is a hard drive. It should be noted that the computer-readable medium can also be other mediums such as compact discs, digital video discs, flash memories or other memory technologies commonly used. In such an embodiment, the data disc500is one type of a tangible computer-readable medium500.

The instructions510may also be downloaded to a computer data reading device, such as the controller110,210or other device capable of reading computer coded data on a computer-readable medium, by comprising the instructions510in a computer-readable signal which is transmitted via a wireless (or wired) interface (for example via the Internet) to the computer data reading device for loading the instructions510into a controller. In such an embodiment, the computer-readable signal is one type of a non-tangible computer-readable medium500.

References to computer program, instructions, code etc. should be understood to encompass software for a programmable processor or firmware such as, for example, the programmable content of a hardware device whether instructions for a processor, or configuration settings for a fixed-function device, gate array or programmable logic device etc. Modifications and other variants of the described embodiments will come to mind to one skilled in the art having benefit of the teachings presented in the foregoing description and associated drawings. Therefore, it is to be understood that the embodiments are not limited to the specific example embodiments described in this disclosure and that modifications and other variants are intended to be included within the scope of this disclosure. Still further, although specific terms may be employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation. Therefore, a person skilled in the art would recognize numerous variations to the described embodiments that would still fall within the scope of the appended claims. As used herein, the terms “comprise/comprises” or “include/includes” do not exclude the presence of other elements or steps. Furthermore, although individual features may be included in different claims, these may possibly advantageously be combined, and the inclusion of different claims does not imply that a combination of features is not feasible and/or advantageous. In addition, singular references do not exclude a plurality.