Patent Description:
Automated or robotic power tools such as robotic lawnmowers are becoming increasingly more popular. In a typical deployment a work area, such as a garden, is enclosed by a boundary cable with the purpose of keeping the robotic lawnmower inside the work area. Additionally or alternatively, the robotic work tool may be arranged to navigate using one or more beacons, such as Ultra Wide Band beacons, or optical beacons. Additionally or alternatively, the robotic work tool may be arranged to navigate using satellite positioning sensors, such as Global Positioning System (GPS) or Global Navigation Satellite System (GLONASS) sensors.

A robotic work tool is typically arranged to operate under different circumstances and the contemporary user requires a wide range of functions from a robotic tool, such as mapping of the work area, advanced scheduling, theft control and so on. The sheer number of functions and their advanced level requires that robotic work tools are properly set up and also trained. The extensive setup is time consuming and may be more difficult and complex than a standard user may be capable of performing, and the training may require additional computer resources and also time to be completed.

Especially for robotic work tool systems where more than one robotic work tool is set up to operate requires additional devices, such as system servers and dedicated communication systems and protocols, which makes such system even more complex to set up and requiring more time to train.

The patent application published as <CIT> discloses a system for providing autonomous lawn care services. The system includes a number of autonomous outdoor power devices, and one or more service vehicles. The one or more service vehicles are configured to selectively load and unload one or more of the autonomous outdoor power devices at a jobsite based on instructions received by a controller of the one or more service vehicles.

The patent application published as <CIT> discloses a network of modular, multitier mobile units that are each capable of collecting data for processing as a user uses them in their residence or business premises performing a task or a chore, or as they move about within an area in a property based on their mobility capabilities and current location. The modular, multitier mobile units are designed including NFC or other near or full contact pads on which emitters and/or sensor units and/or other robot mechanical/electrical units can be docked and powered without requiring connectors. The modular, multitier mobile unit networks are designed to function in many different tiers, such as tier zero node, tier one node, tier two node and tier three cloud node, each having capabilities to process the collected data. The modular, multitier mobile units are capable of sharing the collected data and resources with each other. The tier three cloud node provides additional processing power that does not exist in lower level tiers and also provides artificial intelligence, voice recognition and synthesis, face recognition capabilities.

The patent application published as <CIT> discloses an intelligent gardening system, for monitoring and controlling gardening apparatuses in a gardening area, including: multiple sensors that collect environmental information of the gardening area; one or more gardening apparatuses that perform gardening work according to a control instruction; and a control center that generates the control instruction based on the environmental information; wherein the sensors, the gardening apparatuses and the control center communicate with each other to form an Internet of Things.

Thus, there is a need for improved setup, training and operation for a robotic work tool, such as a robotic lawnmower.

It is therefore an object of the teachings of this application to overcome or at least reduce those problems by providing a robotic work tool system according to claim <NUM>.

In one embodiment or combination of embodiments the robotic work tool is a robotic lawnmower.

Other features and advantages of the disclosed embodiments will appear from the following detailed disclosure, from the attached dependent claims as well as from the drawings. All references to "a/an/the [element, device, component, means, step, etc.]" are to be interpreted openly as referring to at least one instance of the element, device, component, means, step, etc., unless explicitly stated otherwise.

The invention will be described in further detail under reference to the accompanying drawings in which:.

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. Like reference numbers refer to like elements throughout.

It should be noted that even though the description given herein will be focused on robotic lawnmowers, the teachings herein may also be applied to, robotic ball collectors, robotic mine sweepers, robotic farming equipment, or other robotic work tools where lift detection is used and where the robotic work tool is susceptible to dust, dirt or other debris.

<FIG> shows a perspective view of a robotic working tool <NUM>, here exemplified by a robotic lawnmower <NUM>. It should be noted that although the robotic work tool is exemplified here as a robotic lawnmower, the teachings herein may equally beneficially be implemented in a robotic manure distributor, robotic irrigation tool, robotic leaf collector, or other robotic gardening tool, especially if working in cooperation with a robotic lawnmower. The teachings herein may equally beneficially be implemented in a robotic ball collector. In the example illustrated in <FIG>, the robotic lawnmower has a body <NUM> and a plurality of wheels <NUM> (only one shown). The robotic lawnmower <NUM> may comprise charging skids for contacting contact plates (not shown in <FIG>) when docking into a charging station (not shown in <FIG>, but referenced <NUM> in <FIG>) for receiving a charging current through, and possibly also for transferring information by means of electrical communication between the charging station and the robotic lawnmower <NUM>.

The robotic working tool <NUM> may be of an articulated or multi-chassis design as in <FIG>, having a main or first body part and a trailing or second body part. The two parts are connected by a joint part.

The robotic working tool <NUM> may be of a mono-chassis design as in <FIG> shows a schematic overview of the robotic working tool <NUM>, also exemplified here by a robotic lawnmower <NUM>. In this example embodiment the robotic lawnmower <NUM> is of a mono-chassis type, having a main body part <NUM>. The main body part <NUM> substantially houses all components of the robotic lawnmower <NUM>. The robotic lawnmower <NUM> has a plurality of wheels <NUM>. In the exemplary embodiment of <FIG> the robotic lawnmower <NUM> has four wheels <NUM>, two front wheels and two rear wheels. At least some of the wheels <NUM> are drivably connected to at least one electric motor <NUM>. It should be noted that even if the description herein is focused on electric motors, combustion engines may alternatively be used, possibly in combination with an electric motor. In the example of <FIG>, each of the wheels <NUM> is connected to a respective electric motor. This allows for driving the wheels <NUM> independently of one another which, for example, enables steep turning and rotating around a geometrical center for the robotic lawnmower <NUM>. It should be noted though that not all wheels need be connected to each a motor, but the robotic lawnmower <NUM> may be arranged to be navigated in different manners, for example by sharing one or several motors <NUM>.

The robotic lawnmower <NUM> also comprises a grass cutting device <NUM>, such as a rotating blade <NUM> driven by a cutter motor <NUM>. The grass cutting device being an example of a work tool <NUM> for a robotic work tool <NUM>. The robotic lawnmower <NUM> also has (at least) one battery <NUM> for providing power to the motors <NUM> and/or the cutter motor <NUM>.

The robotic lawnmower <NUM> also comprises a controller <NUM> and a computer readable storage medium or memory <NUM>. The controller <NUM> may 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 the memory <NUM> to be executed by such a processor. The controller <NUM> is configured to read instructions from the memory <NUM> and execute these instructions to control the operation of the robotic lawnmower <NUM> including, but not being limited to, the propulsion of the robotic lawnmower. The controller <NUM> may be implemented using any suitable, available processor or Programmable Logic Circuit (PLC). The memory <NUM> may 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 robotic lawnmower <NUM> is further be arranged with a wireless communication interface <NUM> for communicating with a cloud service (not shown in <FIG>, but referenced <NUM> in <FIG>), directly or indirectly by communicating through another device, such as a server, a personal computer or smartphone, a second robotic work tool or the charging station. Examples of such wireless communication devices are WiFi® (IEEE <NUM>. 11b), Bluetooth®, Global System Mobile (GSM) and LTE (Long Term Evolution), to name a few. In one embodiment, the wireless communication is achieved through the control signal being transmitted in the boundary cable (the sensing of which is wireless).

For enabling the robotic lawnmower <NUM> to navigate, the robotic work tool <NUM> is arranged with at least one navigation sensor <NUM>. In one embodiment or combination of embodiments the navigation sensor <NUM> is a magnetic field sensor <NUM>. In an additional or alternative embodiment the navigation sensor <NUM> is a beacon sensor <NUM>. In an additional or alternative embodiment the navigation sensor <NUM> is a satellite navigation sensor <NUM>. In an additional or alternative embodiment the navigation sensor <NUM> is a collision sensor <NUM>. In an additional or alternative embodiment the navigation sensor <NUM> is a deduced reckoning (or dead reckoning) sensor <NUM>.

To enable the robotic lawnmower <NUM> to navigate with reference to a boundary cable (not shown in <FIG>, but referenced <NUM> in <FIG>) emitting a magnetic field caused by a control signal (not shown in <FIG>, but referenced <NUM> in <FIG>) transmitted through the boundary cable, the robotic lawnmower <NUM> may be further configured to have at least one magnetic field sensor <NUM> arranged to detect the magnetic field (not shown) and for detecting the boundary cable and/or for receiving (and possibly also sending) information from a signal generator (will be discussed with reference to <FIG>). In some embodiments, the sensors <NUM> may be connected to the controller <NUM>, and the controller <NUM> may be configured to process and evaluate any signals received from the sensors <NUM>. The sensor signals are caused by the magnetic field being generated by the control signal being transmitted through the boundary cable. This enables the controller <NUM> to determine whether the robotic lawnmower <NUM> is close to or crossing the boundary cable, or inside or outside an area enclosed by the boundary cable.

It should be noted that the magnetic field sensor(s) <NUM> as well as the boundary cable (referenced <NUM> in <FIG>) and any signal generator(s) (referenced <NUM> in <FIG>) are optional. The boundary cable may alternatively be used as the main and only perimeter marker. The boundary cable may alternatively simply be used as an additional safety measure. The boundary cable may alternatively be used as the main perimeter marker and other navigation sensors (see below) are used for more detailed or advanced operation.

To enable the robotic lawnmower to navigate using beacons, in one embodiment or combination of embodiments the robotic lawnmower <NUM> may further comprise at least one beacon receiver or beacon navigation sensor <NUM>. The beacon receiver may be a Radio Frequency receiver, such as an Ultra Wide Band (UWB) receiver or sensor, configured to receive signals from a Radio Frequency beacon, such as a UWB beacon. The beacon receiver may be an optical receiver configured to receive signals from an optical beacon.

To enable the robotic lawnmower to navigate using satellites, in one embodiment or combination of embodiments the navigation sensor <NUM> is a satellite navigation sensor <NUM>, such as a GPS receiver (Global Positioning System) or other satellite navigation sensor.

To enable the robotic lawnmower to navigate obstacles and physical limits in a work area, in one embodiment or combination of embodiments the navigation sensor <NUM> is a collision detection sensor <NUM>. A collision sensor may be optical, electromagnetic or mechanical, or any combination thereof. As a skilled person would understand there are many different variations of collision detection sensors. The general operation of a collision detection sensor is that it senses the range to an object, either through sending out a signal and timing the reflection, by capturing an image that is processed or by sensing physical contact.

To enable the robotic lawnmower <NUM> to navigate without outside input (such as beacon or satellite signals) the navigation sensor <NUM> comprises one or more deduced reckoning sensors <NUM>. In one embodiment or combination of embodiments at least one deduced reckoning sensor is a direction sensor <NUM>, such as a compass, an accelerometer or a gyroscope. In one embodiment or combination of embodiments at least one deduced reckoning sensor <NUM> is a distance sensor, such as an accelerometer or gyroscope with timing function, or an odometer, such as a wheel turns counter. In one embodiment or combination of embodiments, the deduced navigation sensor <NUM> is a barometer utilized for determining elevational travel. Such a barometer may also be used as an environmental sensor for determining weather changes.

The robotic lawnmower may also comprise other sensors <NUM>, for example a rain sensor, a cutting force sensor, a grass height sensor, an inclinometer, a temperature sensor, a light intensity sensor, a barometer, or other sensors.

<FIG> shows a schematic view of a robotic working tool system <NUM> in one embodiment or combination of embodiments. The schematic view is not to scale. The robotic working tool system <NUM> comprises a charging station <NUM> having a signal generator <NUM> and a robotic working tool <NUM>. As with <FIG>, the robotic working tool is exemplified by a robotic lawnmower, whereby the robotic work tool system may be a robotic lawnmower system or a system comprising a combinations of robotic work tools, one being a robotic lawnmower, but the teachings herein may also be applied to other robotic working tools adapted to operate within a work area.

The robotic working tool system <NUM> may also comprise a boundary cable <NUM> arranged to enclose a work area <NUM>, in which the robotic lawnmower <NUM> is supposed to serve. A control signal <NUM> generated by the signal generator <NUM> is transmitted through the boundary cable <NUM> causing a magnetic field (not shown) to be emitted.

The robotic working tool system <NUM> may also optionally comprise at least one beacon <NUM> to enable the robotic lawnmower to navigate the work area using the beacon navigation sensor(s) <NUM>.

The work area <NUM> is in this application exemplified as a garden, but can also be other work areas as would be understood. The garden contains a number of obstacles (O), exemplified herein by a number (<NUM>) of trees (T) and a house structure (H). The trees are marked both with respect to their trunks (filled lines) and the extension of their foliage (dashed lines). The garden may also comprise other features such as a sloping part, indicated by dashed contour lines referenced "S" in <FIG>.

The robotic lawnmower is in one embodiment or combination of embodiments configure to determine it the robotic lawnmower is operating in a new work area <NUM>. The determination may be performed at startup, during a setup mode or dynamically during operation, or a combination of any or all.

In one such embodiment, the robotic lawnmower <NUM> is configured to determine that it is in a new work area by identifying an identification for the charging station or the work area, the charging station representing the work area, and compare it to a register of (known) charging stations. The register may be stored locally in the memory <NUM> of the robotic lawnmower and/or centrally in the cloud service. The identification of the charging station may be retrieved by sensing and processing the control signal in an embodiment where the signal generator transmits an identifier for the charging station as part of or appended to the control signal <NUM>. In one embodiment or combination of embodiments, the identification may be retrieved through a communication channel between the robotic lawnmower <NUM> and the charging station <NUM>. In one embodiment or combination of embodiments, the identification may be based on the current position of the robotic lawnmower <NUM>. In one such embodiment, the robotic lawnmower <NUM> is configured to determine its current position and query a register of charging stations or work areas based on position to determine if the work area is a new work area. In such an embodiment, the actual identity of the charging station or work area may then be omitted and replaced by simply determining whether the work area is new to the robotic lawnmower <NUM>. For the purpose of this application, the determination of the current position will be considered to be a determination of an identifier for the charging station or work area, as the position corresponds to the work area or charging station.

The robotic lawnmower system <NUM> may additionally comprise a second (or more) additional robotic work tools <NUM>. The additional robotic work tool(s) <NUM> may be of the same type as the robotic lawnmower <NUM> or they may be of different types, and also need not be of the same type.

As has been discussed with reference to <FIG>, the robotic lawnmower <NUM> is arranged to contact a cloud service <NUM> through the communication interface <NUM>. As a cloud service does not require a dedicated connection, the connection to the cloud service may be established directly or indirectly.

The inventors have realized that some prior art systems that utilize dedicated servers suffer from drawbacks. A dedicated server is a physical server that is used entirely for one need. The dedicated server requires a proprietary interface and protocols and require capacity and expertise to manage ongoing maintenance, patches and upgrades. The inventors have realized that a simple solution is available in going against predominant thinking in the area of garden and forest robotics in utilizing a cloud service to overcome all these problems.

The inventors have realized that by utilizing the vast processing resources, the easy access and the centralized availability available to a cloud server, sensor data from several different sensors, possibly also from several different robotic lawnmowers <NUM> can be collated and analysed to provide an improved operation of a robotic lawnmower <NUM>. The data to be sent can be sensor values of the navigation sensors (GPS, loop sensors, guide sensors, collision sensors, gyroscope, compass, wheel rotation tics and accelerometer), but also from other environmental sensors such as a barometer. The sensor data can be processed in the cloud, or pre-processed in the robotic lawnmower before being transmitted to the cloud service <NUM>. The preprocessing may be as simple as a transformation and/or a combination of data, or more complicated.

In general, the robotic work tool according to herein can be seen as to cause the cloud service to perform certain functions and/or analysis by transmitting the data needed for such analysis or functions.

The data may be analysed as instantaneous data points and/or over time to establish patterns or trends.

As a work area does not change significantly over time, data can be gathered over longer periods of time and subjected to various statistical methods, the large data gathered providing reliable basis for the statistics.

The data gathered can be used by the cloud service to generate a map of a work area. By combining location data with sensor data (such as collision data) and elevation data a general outline of the work area can be provided marking all objects (indicated as where collisions occur consistently over time) and slopes (indicated as locations with consistent elevation changes).

The data gathered can be used by the cloud service to handle segmentation of the work area. Over time, the analysis made by the cloud service will provide indications of which sub areas or segments of the work area that need most or least work. Trends such as if one sub area is serviced before another, certain benefits arise, may also be realized through the analysis over time. For example, if it is noted that if the air pressure is low, a certain segment requires double time to be serviced properly, this area may be segmented and serviced accordingly when the air pressure drops (probably indicating rain).

The cloud service may also be arranged to base path finding algorithm on the gathered data.

As the inventors have realized, as most work areas for a type of robotic work tool, such as a garden for a robotic lawnmower, comprise essentially the same components; grass lawn, trees, some rocks, possibly some gravel and some buildings, data may be shared between different robotic lawnmowers. By gathering data for a first robotic work tool <NUM>, such as a robotic lawnmower, and a second robotic work tool <NUM>, general trends and correspondences may be retrieved from the analysis. As a map for a first robotic work tool <NUM> is generated based on data gathered over time, where the data gathered is compared to several criteria for identifying or determining the object to be put on the map, there are benefits in utilizing data gathered by other robotic work tools, as such data is used to train the determination for the first robotic work tool. For example, if a collision detection sensor provides input indicating a collision at the same location as an accelerometer provides data indicating an abrupt stop followed by shaking, and such data is trending also for other robotic lawnmowers, it can be assumed that there is a rock or wall at that location, without having to repeat over time, relying on data gathered for other robotic work tools to train the analysis for the first robotic work tool. The cloud service is thus arranged to train its analysis for a first robotic work tool based on data gathered for a second robotic work tool.

The inventors have also realized that utilizing the cloud service, the startup of a new robotic work tool in a work area may be made more efficient by all robotic work tools uploading their work area settings to the cloud service <NUM>. As a robotic work tool determines that it is started up or installed in a previously not worked work area (see above for a manner of identifying a work area), the robotic work tool may query the settings form the cloud service.

In this manner, it is easy to allow different robotic work tools to operate in new work areas, thereby enabling an easy replacement of robotic work tools or collaborations of robotic work tools. As an robotic work tool downloads work area settings based on the work area identifiers, more than one robotic work tool may operate in the same work area, contrary to the dedicated prior art systems requiring double system setups.

In one embodiment or combination of embodiments, the cloud service is also arranged to determine if the robotic work tool is authorized to operate in a work area. This is useful for unauthorized use of robotic work tools and provides theft protection as a stolen robotic work tool will not be able to be started in any work area other than its home work area.

In one embodiment the cloud service is arranged to coordinate a first and a second robotic work tool so that a work area is best serviced. The coordination is based on the capabilities of the first and second robotic work tools. For example if the first robotic work tool <NUM> has a longer range than the second robotic work tool <NUM>, the first robotic work tool will be controlled to operate in segments (or sub areas) farther from the charging station, and the second robotic work tool will be controlled to operate in segments (or sub areas) closer to the charging station.

If a segment contains slopes of a high inclination, the robotic work tool having the best climbing ability will be controlled to service such a segment. The climbing capability may be specified in and provided by the robotic work tool, or it may be retrieved from the analysis of the data gathered by that robotic work tool. A consistent or regularly higher speed (or lower power consumption) in slopes for a first robotic work tool (individual robotic work tool and/or model of robotic work tool) than for a second robotic work tool (individual robotic work tool and/or model of robotic work tool) indicates a better climbing capability for the first robotic work tool (individual robotic work tool and/or model of robotic work tool). This saves a user or operator from having to buy two advanced robotic work tools as an advanced robotic work tool can be utilized to handle complicated segments or tasks, and a simpler model can be utilized to handle simpler segments and/or tasks.

The cloud service is in one embodiment or combination of embodiments arranged to estimate the height of the grass being cut in a work area for a robotic lawnmower <NUM>. The grass height may be based on sensor data (such as load on the motor <NUM>). The grass height may also be estimated based on growth projection models and/or weather data for the work area. Based on the estimated grass height and/or growth in a segment, the cloud service can control the first and the second robotic work tool so that the segment is properly serviced (i.e. obtains a level of service so that a desired result (grass height) is achieved. This feature will reduce the cutting time and thereby save energy consumption, reduce wear of the robotic lawnmower and on the grass.

The user will thereby save money and time not to buy two advanced mowers for steep areas or make double installations.

As has been disclosed in the above, the inventors have realized several problems with the contemporary prior art systems, and also realized simple and inventive manners for overcoming these problems. Supplementary descriptions of these solutions will be given below with reference to <FIG>, <FIG>, <FIG>, <FIG>. It should be noted that any, some or all of the embodiments disclosed herein may be combined in a robotic work tool and/or a robotic work tool system according to the teachings herein.

<FIG> shows a schematic view of a robotic work tool system <NUM>, exemplified herein by a robotic lawnmower system. In one embodiment or combination of embodiments, the robotic lawnmower system <NUM> is a robotic lawnmower system <NUM> as disclosed with reference to <FIG>. As in <FIG>, the robotic lawnmower system <NUM> comprises a robotic work tool <NUM>, exemplified by a robotic lawnmower <NUM>. In one embodiment or combination of embodiments, the robotic lawnmower <NUM> is a robotic lawnmower as disclosed with reference to <FIG>.

The robotic lawnmower <NUM> is placed in a work area <NUM> and the robotic lawnmower <NUM> is configured to determine which settings should be used for the work area <NUM>. The determination may be done during setup of the robotic lawnmower system or the robotic lawnmower. Alternatively or additionally, the determination may be done during startup of the robotic lawnmower <NUM>. Alternatively or additionally, the determination may be done during operation of the robotic lawnmower <NUM>, such as at regular intervals. Alternatively or additionally, the determination may be done during operation of the robotic lawnmower <NUM>, such as when a control signal is lost or not reliably received. Alternatively or additionally, the determination may be done during operation of the robotic lawnmower <NUM>, such as when it is determined that a border of the work area has been crossed (by detecting a crossing of a border cable and/or by determining a border crossing based on a determined location.

<FIG> shows a flowchart for a general method of determining which settings should be used for a work area. A communication channel or connection with a cloud service <NUM> is established <NUM> by the robotic lawnmower <NUM>. In order to determine the settings to be used for the work area <NUM>, the robotic lawnmower <NUM> identifies <NUM> the work area <NUM>.

In one embodiment or combination of embodiments, the identification of the work area is a direct identification of the work area. In one such embodiment, the robotic lawnmower determines a location <NUM> utilizing the navigation sensor <NUM>, such as a beacon navigation sensor <NUM> or a satellite navigation sensor <NUM>. In one such embodiment, the robotic lawnmower determines an identity of the signal generator <NUM> utilizing the navigation sensor <NUM>, such as a magnetic field sensor <NUM>, whereby the identity of the signal generator (corresponding to the work area) is determined based on the received control signal <NUM>.

In one embodiment or combination of embodiments, the identification of the work area is an indirect identification of the work area, by identifying the charging station (assumed to comprise a signal generator) corresponding to the work area. In one such embodiment, the robotic lawnmower determines an identity of the signal generator <NUM> utilizing the navigation sensor <NUM>, such as a magnetic field sensor <NUM>, whereby the identity of the signal generator (corresponding to the work area) is determine based on the received control signal <NUM>.

In one embodiment or combination of embodiments, the determination of the identifier for the work area is made by the controller of the robotic lawnmower <NUM>. In one embodiment or combination of embodiments, the determination of the identifier for the work area is caused by the controller of the robotic lawnmower <NUM> to be made by the cloud server <NUM> (by requesting it or by responding to a request).

As an identifier for the work area has been determined, corresponding settings for the work area is retrieved <NUM> and the robotic lawnmower <NUM> loads them into the memory <NUM> and is ready to operate <NUM> in the work area <NUM>.

In <FIG> the work area <NUM> comprises two work areas or segments, a first (main) work area or segment <NUM> and a second work area or segment <NUM>. In the example of <FIG>, the second work area <NUM> does not have a charging station, nor a signal generator. In prior art systems, if a robotic work tool is to be set to operate in such a (second) work area, a special mode for operating in a work area without charging capabilities (a secondary work area mode) needed to be entered manually by an operator. The special mode directs how the robotic work tool is to handle charging situations.

In one embodiment or combination of embodiments, instructions for entering such a mode is comprised in the settings for the work area. In order for the first work area to be distinguishable from the second work area, at least two different solutions exist (that may be combined). The first manner is to utilize a second guide or boundary cable (not shown explicitly but assumed to be indicated through the general boundary cable reference <NUM> in <FIG>). The second manner is to determine a location for the second work area <NUM>.

The user will thus not have to enter the secondary work area mode in the mower when it is used in a secondary area.

<FIG> shows a schematic view of a robotic work tool system <NUM>, exemplified herein by a robotic lawnmower system. In one embodiment or combination of embodiments, the robotic lawnmower system <NUM> is a robotic lawnmower system <NUM> as disclosed with reference to <FIG> and/or <NUM>. The robotic lawnmower system <NUM> comprises at least two robotic work tools <NUM>, exemplified by robotic lawnmowers <NUM>. In one embodiment or combination of embodiments, the robotic lawnmower <NUM> is a robotic lawnmower as disclosed with reference to <FIG>.

In the example of <FIG>, the robotic work tool system <NUM> comprises at least two robotic work tool subsystems, a fist system <NUM> and a second system <NUM>. Even though the two robotic work tool systems <NUM> and <NUM> are shown to be identical, this is only for illustrative purposes and a skilled person would understand that the two systems may differ.

<FIG> shows how a first robotic lawnmower <NUM> is arranged to establish a connection in order to retrieve data, such as settings, from a cloud service <NUM>. <FIG> shows how a second robotic lawnmower <NUM> is arranged to establish a connection in order to retrieve data, such as settings, from the same cloud service <NUM>. If the robotic lawnmowers are arranged according to the teachings herein, they may be used in either of the work areas. As one robotic work tool <NUM> is moved from one work area to another, the robotic work tool <NUM> retrieves new settings from the cloud service. As the settings are received from the cloud service, the settings may easily be loaded into more than one robotic work tool, thereby enabling a simple and easy use of more than one robotic work tool in a work area, which use of multiple robotic work tools is easy to change dynamically or repeatedly.

As discussed in the above, the cloud service <NUM> is, in one embodiment or combination of embodiments, configured to generate a map of a work area, based on sensor data gathered by a robotic work tool operating in the work area.

As the cloud service has a lot more processing power available, the cloud service can utilize more advanced algorithms for processing the gathered data and to generate the map.

Furthermore, as the inventors have realized, because the cloud service <NUM> is associated with more than one robotic work tool, the cloud service <NUM> is, in one embodiment or combination of embodiments, configured to generate a map of a work area based on data gathered from a first robotic work tool and on data gathered from a second robotic work tool. This enables the map to be generated faster as more data will be made available for generating the map. It also enables for a replacement or new robotic work tool to benefit from a replaced or older robotic work tool's data gathering. It may also enable two or more robotic work tools operating in a same work area for generating a map fast during an installation or setup of the work area.

In one embodiment or combination of embodiments, the data gathered from the second robotic work tool is associated with the work area. In an additional or alternative embodiment, the data gathered from the second robotic work tool is associated with another work area and/or the second robotic work tool. This enables for data trends for robotic work tools, possibly of a particular type and/or arranged with a type of sensor, so that more accurate estimations based on the sensor data may be achieved, such as differentiating between different surfaces, different objects, different structures, and so on.

In one embodiment, the cloud service is configured to determine the operating data based on the received gathered data. In addition, in one embodiment, the cloud service is further configured to determine the operating data based on gathered data previously transmitted to the cloud service. This enables the cloud service to take into account previously gathered data which may influence the operating data. For example, if the gathered data indicates a grass height, then the previously gathered data in comparison with the currently gathered data will indicate a growth rate and a change to the operating schedule may be determined to keep the grass height within acceptable parameters. In addition or as an alternative, in one embodiment, the cloud service is further configured to determine the operating data based on operating data previously determined by the cloud service. This enables the cloud service to correct or amend operating data based on knowledge of the previously transmitted operating data. For example, if the gathered data represents grass height and the operating data represents operating intensity and/or frequency, a comparison of the two may lead to that the operating intensity and/or frequency is altered, for example by increasing it if the gathered grass height is above acceptable limits or decreasing it f the gathered grass height is below acceptable limits.

<FIG> is a flow chart for a general method of generating a map of a work area according to the teachings herein. The cloud service <NUM> receives <NUM> sensor data gathered by a first robotic work tool <NUM>. The cloud service <NUM> furthermore receives <NUM> sensor data gathered by a second robotic work tool <NUM>. In one embodiment or combination of embodiments, the data gathered by the second robotic work tool is received from the second robotic work tool <NUM>. In one embodiment or combination of embodiments, the data gathered by the second robotic work tool is received from a storage or memory associated with the second robotic work tool <NUM>. This enables a map to be generated on previously recorded data allowing for data gathering over an extended time period providing a higher statistical reliability. The cloud service generates <NUM> the map based on the data gathered by the first robotic work tool <NUM> and on the data gathered by the second robotic work tool <NUM>.

In the above it was disclosed how a robotic work tool may retrieve settings for a work area utilizing the cloud service <NUM>.

One advantage of retrieving settings from a cloud service is that theft protection may be provided in a simple manner. The robotic work tool <NUM> is arranged to provide an identifier of itself as it requires settings for a work area. The identifier of the robotic work tool is matched against the work area and it is determined if the robotic work tool is authorized to operate in that work area. If not, no work area settings will be provided. Alternatively, work area settings will be provided indicating a lock down of the robotic work tool. In both cases, the robotic work tool is rendered unable to operate in the maliciously intended unauthorized manner. The settings thus comprise instructions that renders the robotic lawnmower inoperable.

Another or additional advantage of retrieving settings from and/or gathering data for a cloud service is that a fleet of robotic work tools may be organized and coordinated with a minimum of setup and manual operations.

In the above it has been disclosed how settings may be downloaded to a robotic work tool for operating in a work area. It has also been disclosed how a map may be generated based on input from a plurality of robotic work tools. The inventors have further realized that since the cloud service receives data gathered from different robotic work tools, and since the cloud service has access to maps for the work areas, the cloud service can be utilized to coordinate a fleet of robotic work tools and/or for scheduling work to be performed in a work area. The work to be performed may be scheduled based on time efficiency and/or cost efficiency.

<FIG> shows a flowchart of a general method according to the teachings herein.

In one embodiment or combination of embodiments, the cloud service <NUM> is configured to determine <NUM> at least one operating characteristic or capabilities for a robotic work tool.

In one embodiment or combination of embodiments, the operating characteristic is determined by being received from the robotic work tool or from a register over the robotic work tool.

In one embodiment or combination of embodiments, the operating characteristic is determined based on gathered data. The operating characteristic may be determined based on data gathered from the robotic work tool and/or based on data gathered from another robotic work tool of a same type and/or comprising similar or the same equipment.

In one such embodiment, where the operating characteristic is the range of the robotic work tool, the range may be determined by noting and averaging the time it takes for the robotic work tool to run low on battery over time.

In one such embodiment, where the operating characteristic is the speed of the robotic work tool, the speed may be determined by noting - over time - the time it takes for the robotic work tool to run a distance.

In one such embodiment, where the operating characteristic is the operating efficiency, such as cutting efficiency, of the robotic work tool, the operating efficiency may be determined by noting - over time - the decrease in work load subjected on the robotic work tool (cutting efficiency may be measured by noting the load exerted on the cutter motor for example).

In one such embodiment, where the operating characteristic is the climbing capability of the robotic work tool, the climbing capability may be determined by noting - over time - the time it takes for the robotic work tool to climb a specific gradient.

The cloud service <NUM> is also configured, in one embodiment or combination of embodiments, to determine <NUM> characteristics of the work area, and to match <NUM> the characteristics of the work area to a robotic work tool whose operating characteristics matches - or are capable to service the work area characteristics, and to select that (type of) robotic work tool to be used for the work area. In one embodiment or combination of embodiments the cloud service <NUM> selects <NUM> a robotic work tool (or type of) by recommending or indicating the (type of) robotic work tool. In one embodiment or combination of embodiments the cloud service selects a robotic work tool (or type of) by controlling the (type of) robotic work tool to operate in the work area.

In one embodiment or combination of embodiments, the cloud service is configured to divide the work area into smaller work areas or segments, and perform the scheduling disclosed above for the segments, recommending or controlling the most suitable robotic work tool (out of the available) for the segment.

<FIG> shows a schematic view of a robotic work tool system <NUM> according to an embodiment of the teachings herein. The robotic work tool system <NUM> shown in <FIG> differs from the robotic work tool systems shown in <FIG>, <FIG> and <FIG>, in that only the robotic work tools <NUM>, <NUM> comprised in the robotic work tool system and the associated cloud service <NUM> are shown. <FIG> illustrates the simplicity of the robotic work tool system according to herein where a cloud service is utilized to provide settings, scheduling and or control to one or several robotic work tools based on data gathered from one or several robotic work tools. The system is highly flexible and scalable. Any component of the system may be augmented or replaced without affecting the other components of the system and any changes made will propagate through the system without user interaction being required.

<FIG> shows a flowchart of a general method according to the teachings herein. The cloud service <NUM> receives <NUM> data from the first robotic work tool <NUM> and analyses the data <NUM>. The cloud service <NUM> also receives <NUM> data from the second robotic work tool <NUM> and analyses <NUM> the data received from the first robotic work tool <NUM> based on the data received from the second robotic work tool <NUM>. The robotic work tool <NUM> receives <NUM> data from the cloud service <NUM>, and operates <NUM> according to the received data. The data may comprise settings and/or control commands.

Returning to <FIG>, the robotic work tool system may also be arranged with one or more accessory devices 240a-c. In the example of <FIG>, three accessory devices are shown, but it should be noted that any number of accessory devices (zero or more) may be comprised in the robotic work tool system <NUM>. The accessory device(s) is also configured to establish a connection with the cloud service (only indicated for the accessory device 240a in <FIG>) for transmitting and/or receiving data.

In one embodiment, the accessory device is a passive device, capable of gathering data. One example of such passive accessory device is a rain sensor. If the rain sensor senses an increase in precipitation, the cloud server can direct the robotic lawnmower to postpone operation to a later time, or possibly to increase the charging times between operations to account for the heavier workload posed by the wet grass.

Another example is a camera or other presence sensor. If the camera or other presence sensor, senses or otherwise determines the presence of humans or pets, the cloud server can direct the robotic lawnmower to postpone operation to a later time or to direct the operation to another location or work area.

In one embodiment, the accessory device is an active device, capable of receiving operating data from the cloud server and to operate according to the received operating data. One example of such an active accessory device is a water sprinkler.

Claim 1:
A robotic work tool system (<NUM>) comprising a cloud service (<NUM>) and at least one robotic work tool (<NUM>) arranged to operate in a work area (<NUM>), the robotic work tool (<NUM>) comprising at least one sensor (<NUM>) and a communication interface (<NUM>), the robotic work tool (<NUM>) being configured to
establish a connection to the cloud service (<NUM>) through said communication interface (<NUM>);
receive data gathered by the at least one sensor (<NUM>) and transmit the gathered data to the cloud service (<NUM>) causing the cloud service to analyze the gathered data;
receive operating data from the cloud service (<NUM>); and to
operate at least one robotic work tool (<NUM>) based on the operating data received from the cloud service, wherein the robotic work tool system (<NUM>) is characterized in that the robotic work tool is configured to cause the cloud service to coordinate a first and a second robotic work tool so that the first and second robotic work tools are coordinated to service the work area according to their capabilities, selecting the robotic work tool having the better capability for a given task, and the robotic work tool (<NUM>) is configured to receive coordination data from the cloud service, wherein the coordination is based on operating characteristics of the first and second robotic work tools and wherein the operating characteristic is the range of the robotic work tool, the speed of the robotic work tool and/or the climbing capability of the robotic work tool.