TECHNICAL FIELD

This application relates to a system, a charging station, a User Equipment and a method for providing an improved navigation for robotic work tools, such as lawnmowers, in such a system, and in particular to a system, a charging station, a User Equipment and a method for providing an improved reception of satellite signals in a robotic work tool system.

BACKGROUND

Automated or robotic work tools such as robotic lawnmowers are becoming increasingly more popular and so is the use of the robotic work tool in various types of operational areas. Furthermore, there is also a need for placing the robotic work tool in a sheltered area when not in use, or alternatively, users are requesting more freedom in selecting the location of the charging station. At the same time, robotic work tools are becoming more and more reliant on satellite navigation, such as in GPS (Global Positioning System) or GNSS systems. However, as is known, in many types of environments - especially environments where there are trees and structures, such as in a garden in a populated area - there are areas where satellite reception is limited. In such systems, the robotic work tool is not able to operate to its full capacity if not always in line of sight with a plurality of satellites. This is sometimes compensated for using reference stations or base stations to supplement the satellite signals, such as in RTK (Real-Time Kinetics) systems. However, this also requires that both the robotic work tool and the base-station are in line of sight of a plurality of satellites, and thus does not really solve the problems of full freedom when installing a robotic work tool system, especially not when it comes to the placement of the base station. This is especially true in cases where the base station is positioned in the charging station.

As the charging station is usually placed in a sheltered area, where the robotic work tool will be protected or sheltered against environmental influences, such as rain for example, the charging station will most likely be placed close to a structure where it may not be able to receive reliable signals from a sufficient number of satellites to be able to operate as a reliable base-station.

Prior solutions have been provided where the base-station is detachable or not even connected to the charging station and can thus be placed at will. The installation of the robotic work tool system can therefore be quite cumbersome in many situations where a mistake may lead to a reduced accuracy in operation for the robotic work tool or even the robotic work tool being unable to operate correctly.

However, the user will still not be able to know if the base-station is placed in a good position as the user may not be aware of where the satellites are, especially as the satellites move across the sky during the day.

Thus, there is a need for an improved manner of providing the advanced functionality of utilizing satellite navigation while still providing full - or at least - increased freedom for where to place the charging station and to simplify the installation of the robotic work tool system to accommodate these needs.

SUMMARY

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 connected to a User Equipment, the robotic work tool system comprising a base station and a robotic work tool arranged to operate in an operational area, the robotic work tool comprising a satellite navigation sensor, the robotic work tool system comprising a controller configured to: receive an indication of zero or more reliably received satellites from the base station; receive an indication of expected satellites; compare the reliably received satellites to a list of expected satellites; and provide feedback to be displayed on the User Equipment.

In some embodiments the controller is further configured to retrieve the list of expected satellites from a service.

In some embodiments the controller is further configured to retrieve the list of expected satellites from the robotic work tool. In some embodiments the controller is further configured to determine if there is a satellite to be disregarded by determining whether satellites that are not received by the base station are also not received by the robotic work tool.

In some embodiments the controller is further configured to determine one or more missing satellites based on the comparison of the reliably received satellites to the expected satellites; and determine a direction to a missing satellite, wherein the feedback includes an indication of the direction.

In some embodiments the controller is further configured to determine a direction of a reliably received satellite, wherein the feedback includes an indication of the direction.

In some embodiments the controller is further configured to determine a recommendation and wherein the feedback includes an indication of the recommendation.

In some embodiments the controller is further configured to determine the recommendation based on a direction to a received satellite.

In some embodiments the controller is further configured to determine the recommendation based on a direction to a missing satellite.

In some embodiments the controller is further configured to receive a map and wherein the feedback includes the map.

In some embodiments the controller is further configured to determine the recommendation based on an analysis of the map to identify structures.

In some embodiments the analysis is a topological analysis.

In some embodiments the analysis is a feature analysis.

In some embodiments the recommendation includes an indication of a location that is not blocked by structures.

In some embodiments the robotic work tool system comprises a server, wherein the server comprises a controller configured to receive the indication of zero or more reliably received satellites from the base station; receive the indication of expected satellites; and compare the reliably received satellites to the list of expected satellites.

In some embodiments the controller is further configured to provide the feedback to be displayed on the User Equipment by providing an indication of the direction of received satellites and/or missing satellites to the User Equipment, thereby causing the User Equipment to generate the feedback and display the feedback.

In some embodiments the server is comprised in the UE, wherein the server controller is a controller of the UE.

In some embodiments the robotic work tool is a robotic lawnmower.

It is also an object of the teachings of this application to overcome the problems by providing a method for use in a robotic work tool system connected to a User Equipment, the robotic work tool system comprising a base station and a robotic work tool arranged to operate in an operational area, the robotic work tool comprising a satellite navigation sensor, the method comprising: receiving an indication of zero or more reliably received satellites from the base station; receiving an indication of expected satellites; comparing the reliably received satellites to a list of expected satellites; and providing feedback to be displayed on the User Equipment.

It is also an object of the teachings of this application to overcome the problems by providing a method for use in a User Equipment to be operatively connected to a robotic work tool system, wherein the method comprises receiving an indication of feedback and to display the feedback, wherein the feedback includes indication of missing satellites and/or an indication of received satellites by a base station.

In some embodiments the method further comprises receiving an indication of reliably received satellites and/or an indication of missing satellites as the indication of feedback; and generating feedback based on the received indications.

It is also an object of the teachings of this application to overcome the problems by providing a computer-readable medium carrying computer instructions that when loaded into and executed by a controller of a User Equipment enables the User Equipment to implement the method according to herein.

Further embodiments and aspects are as in the attached patent claims and as discussed in the detailed description.

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. Generally, all terms used in the claims are to be interpreted according to their ordinary meaning in the technical field, unless explicitly defined otherwise herein. 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 steps of any method disclosed herein do not have to be performed in the exact order disclosed, unless explicitly stated.

BRIEF DESCRIPTION OF THE DRAWINGS

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

Figure 1 shows a schematic view of the components of an example of a robotic work tool being a robotic lawnmower according to some example embodiments of the teachings herein;

Figure 2 shows a schematic view of the components of an example of a User Equipment according to some example embodiments of the teachings herein;

Figure 3 A shows a schematic view of a robotic work tool system according to some example embodiments of the teachings herein;

Figure 3B shows a schematic view of a robotic work tool system according to some example embodiments of the teachings herein;

Figure 3C shows a schematic view of a robotic work tool system according to some example embodiments of the teachings herein;

Figure 4A shows a schematic view of a User Equipment providing feedback according to some example embodiments of the teachings herein;

Figure 4B shows a schematic view of a User Equipment providing feedback according to some example embodiments of the teachings herein;

Figure 4C shows a schematic view of a User Equipment providing feedback according to some example embodiments of the teachings herein; and

Figure 5 shows a corresponding flowchart for a method according to some example embodiments of the teachings herein. 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. 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.

Figure 1 shows a schematic overview of a robotic work tool 100, here exemplified by a robotic lawnmower 100. The robotic work tool 100 may be a multi-chassis type or a mono-chassis type (as in figure 1). A multi-chassis type comprises more than one main body parts that are movable with respect to one another. A mono-chassis type comprises only one main body part.

It should be noted that robotic lawnmower may be of different sizes, where the size ranges from merely a few decimetres for small garden robots, to even more than 1 meter for large robots arranged to service for example airfields.

It should be noted that even though the description herein is focussed on the example of a robotic lawnmower, the teachings may equally be applied to other types of robotic work tools, such as robotic watering tools, robotic golfball collectors, and robotic mulchers to mention a few examples.

In some embodiments, and as will be discussed below, the robotic work tool is a semi-controlled or at least supervised autonomous work tool, such as farming equipment or large lawnmowers, for example riders or comprising tractors being autonomously controlled.

It should also be noted that the robotic work tool is a self-propelled robotic work tool, capable of autonomous navigation within a work area, where the robotic work tool propels itself across or around the work area in a pattern (random or predetermined).

The robotic work tool 100, exemplified as a robotic lawnmower 100, has a main body part 140, possibly comprising a chassis 140 and an outer shell 140A, and a plurality of wheels 130 (in this example four wheels 130, but other number of wheels are also possible, such as three or six).

The main body part 140 substantially houses all components of the robotic lawnmower 100. At least some of the wheels 130 are drivably connected to at least one electric motor 155 powered by a battery 150. 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 figure 1, each of the wheels 130 is connected to a common or to a respective electric motor 155 for driving the wheels 130 to navigate the robotic lawnmower 100 in different manners. The wheels, the motor 155 and possibly the battery 150 are thus examples of components making up a propulsion device. By controlling the motors 155, the propulsion device may be controlled to propel the robotic lawnmower 100 in a desired manner, and the propulsion device will therefore be seen as synonymous with the motor(s) 150. It should be noted that wheels 130 driven by electric motors is only one example of a propulsion system and other variants are possible such as caterpillar tracks.

The robotic lawnmower 100 also comprises a controller 110 and a computer readable storage medium or memory 120. The controller 110 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 120 to be executed by such a processor. The controller 110 is configured to read instructions from the memory 120 and execute these instructions to control the operation of the robotic lawnmower 100 including, but not being limited to, the propulsion and navigation of the robotic lawnmower.

The controller 110 in combination with the electric motor 155 and the wheels 130 forms the base of a navigation system (possibly comprising further components) for the robotic lawnmower, enabling it to be self-propelled as discussed.

The controller 110 may be implemented using any suitable, available processor or Programmable Logic Circuit (PLC). The memory 120 may be implemented using any commonly known technology for computer-readable memories such as ROM, FLASH, DDR, or some other memory technology. The robotic lawnmower 100 is further arranged with a wireless communication interface 115 for communicating with other devices, such as a server, a personal computer, a smartphone, the charging station, and/or other robotic work tools. Examples of such wireless communication devices are Bluetooth®, WiFi® (IEEE802.1 lb), Global System Mobile (GSM) and LTE (Long Term Evolution), to name a few. The robotic lawnmower 100 may be arranged to communicate with a user equipment (referenced 200 in figure 2 and figure 3 A, as an example of a connected device) as discussed in relation to figure 2 below for providing information regarding status, location, and progress of operation to the user equipment as well as receiving commands or settings from the user equipment. Alternatively or additionally, the robotic lawnmower 100 may be arranged to communicate with a server (referenced 340 in figure 3 A) for providing information regarding status, location, and progress of operation as well as receiving commands or settings.

The robotic lawnmower 100 also comprises a work tool 160, which in the example of the robotic lawnmower 100 is a grass cutting device 160, such as a rotating blade 160/2 driven by a cutter motor 160/1. In embodiments where the robotic work tool 100 is exemplified as an automatic grinder, the work tool 160 is a rotating grinding disc.

The robotic lawnmower 100 comprises at least one satellite signal navigation sensor 175 configured to provide navigational information (such as position) based on receiving one or more signals from a satellite - possibly in combination with receiving a signal from a base station. In some embodiments the satellite navigation sensor is a GPS (Global Positioning System) device or other Global Navigation Satellite System (GNSS) device. In some embodiments the satellite navigation sensor 175 is a RTK sensor. This enables the robotic work tool to operate in an operational area bounded by virtual borders (referenced 320 in figure 3A).

The robotic lawnmower 100 may also or alternatively comprise deduced reckoning sensors 180. The deduced reckoning sensors may be odometers, accelerometer or other deduced reckoning sensors. In some embodiments, the deduced reckoning sensors are comprised in the propulsion device, wherein a deduced reckoning navigation may be provided by knowing the current supplied to a motor and the time the current is supplied, which will give an indication of the speed and thereby distance for the corresponding wheel.

For enabling the robotic lawnmower 100 to navigate with reference to a wire, such as a boundary wire or a guide wire, emitting a magnetic field caused by a control signal transmitted through the wire, the robotic lawnmower 100 is in some embodiments configured to have at least one magnetic field sensor 170 arranged to detect the magnetic field and for detecting the wire and/or for receiving (and possibly also sending) information to/from a signal generator. In some embodiments, such a magnetic boundary may be used to supplement navigation according to virtual borders.

The robotic lawnmower 100 is in some embodiments arranged to operate according to a map application representing one or more work areas (and possibly the surroundings of the work area(s)) as well as features of the work area(s) stored in the memory 120 of the robotic lawnmower 100. In some embodiments, the map is also or alternatively stored in the memory of a server. The map application may be generated or supplemented as the robotic lawnmower 100 operates or otherwise moves around in the work area. In some embodiments, the map application includes one or more start regions and one or more goal regions for each work area. In some embodiments, the map application also includes one or more transport areas. The robotic work tool 100 is arranged to navigate according to the map based on the satellite navigation sensor 175.

In some embodiments the robotic work tool is arranged or configured to traverse and operate in work areas that are not essentially flat, but contain terrain that is of varying altitude, such as undulating, comprising hills or slopes or such. The ground of such terrain is not flat and it is not straightforward how to determine an angle between a sensor mounted on the robotic work tool and the ground. The robotic work tool is also or alternatively arranged or configured to traverse and operate in a work area that contains obstacles that are not easily discerned from the ground. Examples of such are grass or moss-covered rocks, roots or other obstacles that are close to ground and of a similar colour or texture as the ground. The robotic work tool is also or alternatively arranged or configured to traverse and operate in a work area that contains obstacles that are overhanging, i.e. obstacles that may not be detectable from the ground up, such as low hanging branches of trees or bushes. Such a garden is thus not simply a flat lawn to be mowed or similar, but a work area of unpredictable structure and characteristics. The work area exemplified with referenced to figure 3 A, may thus be such a non-uniform work area as disclosed in this paragraph that the robotic work tool is arranged to traverse and/or operate in.

Figure 2 shows a schematic view of a User Equipment 200. The User Equipment may be a smartphone or a tablet computer, but may also be a personal computer or other computing device.

The User Equipment 200 comprises a controller 210 for controlling the operation of the UE 200, a memory 220 for storing instructions and data relating to the operation of the UE 200 and a communication interface 215 for enabling the UE 200 to communicate with other entities, such as the robotic work tool 100, a base station and/or a server.

The controller, the memory and the communication interface may be of similar types as discussed in relation to figure 1 for the robotic work tool 100.

The UE 200 also comprises a user interface 230 which is enabled to receive input from a user, and to provide output to a user. The user interface 230 may be based on audio, visual and/or tactile operation. In some embodiments, the user interface 230 comprises a display 230A for providing visual output to a user. In some embodiments, the user interface 230 comprises one or more keys 230C for receiving user commands through. In some embodiments, where the display is a touch display, the user interface 230 comprises one or more virtual keys 230B for receiving user input.

Figure 3 A shows a robotic work tool system 300 in some embodiments. The schematic view is not to scale. The robotic work tool system 300 comprises one or more robotic work tools 100 according to the teachings herein arranged to operate in one or more operational areas 305 bounded by a boundary 320. It should be noted that the operational area 305 shown in figure 3A is simplified for illustrative purposes.

The robotic work tool system 300 further comprises a station 310 possibly at a station location. A station location may alternatively or additionally indicate a service station, a parking area, a charging station or a safe area where the robotic work tool may remain for a time period between or during operation session. The robotic work tool system 300 further comprises a base station 313, and the base station is in some embodiments included in the station 310. It should be noted that eventhough the description herein will be focussed on a base station 313 in a charging station 310, the base station 313 need not be placed in the charging station 310 but can be placed at other locations and there may be more than one base station 313 that may be located at other places than in the charging station 310.

The base station 313 is operatively connected to a controller 311. The controller 311 may be a controller of the base station 313 or the controller may be a controller of the charging station 310. The controller 311 controls the base station 313 for receiving satellite signals from zero or more satellites S and to transmit the signals to another entity, such as the robotic work tool 100, the UE 200 and/or to a server 340. The base station 313 is also operatively connected to a communication interface 312. The communication interface 312 may be a communication interface 312 of the base station 313 or the communication interface 312 may be a communication interface 312 of the charging station 310. The communication interface 312 enables the base station 313 to transmit the received satellite signals to another entity, such as the robotic work tool 100, the UE 200 and/or to the server 340.

The server 340 comprises a controller 340A for controlling the operation of the server 340, a memory 340B for storing instructions and data relating to the operation of the server 340 and a communication interface 340C for enabling the server 340 to communicate with other entities, such as the robotic work tool 100, the base station 313 and/or a UE 200. The controller, the memory and the communication interface may be of similar types as discussed in relation to figure 1 for the robotic work tool 100.

The robotic work tool system 300 is also enabled to be connected to a UE 200. The connection may be from any, some or all of the robotic work tool 100, the server 340, the charging station 310 and/or the base station 313. The connection may be direct to a component device of the robotic work tool system or indirect via one of the other component devices of the robotic work tool system 300.

In some embodiments, the UE 200 comprises the server 340, or rather a server application to perform the processing of the server 340. As with figure 1, the robotic work tool(s) 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 work tools adapted to operate within a work area.

As is known RTK systems (or similar) operate by utilizing one or more base stations for supplementing the satellite signals received by for example a robotic work tool 100.

As is shown in figure 3 A there may be obstacles such as houses, structures, trees to mention a few examples that may block signal reception from zero or more satellites S in certain areas, hereafter referred to as shadowed areas. In figure 3 A such obstacles are indicated and referenced H (as in house).

A base station 313 may thus be used to supplement the robotic work tool’s satellite reception and enables for a more accurate determination of a position even in shaded areas.

However, and as is illustrated in figure 3 A, the base station 313 may also be placed in an area where one or more structures H blocks the satellite reception. In figure 3 A the house blocks one of the satellites S in the area of the charging station 310.

It should be noted herein that for illustrative purposes only three satellites are shown, whereas - and as a skilled person would know - it requires a reliable reception of signals from at least 3 satellites and/or base stations for the robotic work tool to be able to determine a position with any kind of accuracy. In fact, in most implementations many more signals are required, commonly 16 satellite signals are required. And, the number of satellites is not necessarily the decisive factor for the accuracy received, but also the spread of the satellites one receives signals from. It should also be noted that even in a shadowed area, the robotic work tool may be able to receive signals from more than three satellites, but not at a signal level where a reliable signal lock can be established. A shadowed area can thus be defined as an area where the robotic work tool (or base station) is unable to receive sufficiently reliable signal reception, i.e. when the number of signals received reliably is under a threshold number, and where a signal is reliably received when it is received at a signal quality level exceeding a threshold value.

As the satellites are usually not clearly visible to the naked eye a user is not aware whether a base station is placed at a location that is shaded or not. The inventors have realized an inventive concept of avoiding such situations.

In the below, several embodiments of how the robotic work tool system may be adapted will be disclosed. It should be noted that all embodiments may be combined in any combination providing a combined adaptation of the robotic work tool system.

The concept proposed by the inventors is to determine which satellites the base station 313 can receive signals from and then to compare this to a list of expected satellites, and to provide feedback through a user equipment allowing the user to move the base station 313. This may be done already upon installation of the robotic work tool system - or even prior to installation of the robotic work tool system to avoid changing any of the installation. It can also be done in real-time, where the user can move the base station until a desired feedback is received.

It should be noted that any processing may be done in any, some or all of the controller 110 of the robotic work tool 100, the controller of the UE 210, the controller 311 of the base station 313 and the controller of the server 340A and that the processing may also be done partially in one system component. This is indicated in figure 3 A in that dashed arrows are shown between the server 340, the base station 313, the UE 200 and the robotic work tool 100 for indicating that information may be passed freely between the components for (partial) processing.

In the following description one example embodiment will be discussed, where the base station 313 receives one or more satellite signals, determines which of these are reliably received (received at a sufficiently good signal quality exceeding a quality threshold), transmits an indication of the reliably received satellites to the server 340. A reliably received satellite thus being a satellite from which a satellite signal is reliably received. The server 340 then compares the reliably received satellites to expected satellites and transmits an indication of this to the UE 200 which provides feedback 250 to the user. In the following further details will be given and it should be noted that the processing discussed may be provided by any, some or all of the robotic work tool system components.

In some embodiments the reliably received satellites are compared to a list of satellites in the area. In some embodiments, such a list of satellites is retrieved via a cloud (or an internet) service. In some embodiments, such a list of satellites is retrieved from the robotic work tool 100 which is configured to determine which satellites are received reliably.

As it is determined which satellites are received (i.e. from which satellites signals are received reliably), the direction where satellites are received can be determined. The direction where satellites are received can be determined based on the position (at the time) of the received satellites. In some embodiments the position can be retrieved from a cloud (or an internet) service.

In some embodiments also which satellites are not received is determined by comparing the reliably received satellites to the list of satellites and the direction where satellites are not received is also determined.

In some embodiments it is further determined if there are directions that are to be disregarded. This can be done by determining whether satellites that are not received by the base station 313 are also not received by the robotic work tool 100. If they are not received by neither of the base station nor the robotic work tool 100, then those satellites are of no use and may be disregarded. Such directions may thus also be disregarded.

Based on the direction(s), the feedback 250 is generated. As indicated above much of the processing herein may be performed by many different system component. In the specific example discussed the server 340 determines the directions and the UE 200 determines the feedback, however, the UE 200 may generate the feedback directly based on the reliably received satellites.

Figure 4A shows schematic views of an example embodiment where feedback 250 is provided visually on the display 230A of the UE 200.

In some embodiments the feedback 250 provided on the UE 200 includes an indication 250A of the base station 313 and an indication 250B of directi on(s) where satellites are not received reliably. In some embodiments the feedback 250 provided on the UE 200 includes an indication 250A of the base station 313 and an indication 250C of direction(s) where satellites are received reliably. In some embodiments the feedback 250 provided on the UE 200 includes an indication 250A of the base station 313, an indication 250B of direction(s) where satellites are not received reliably and an indication 250C of direction(s) where satellites are received reliably.

In some embodiments an indication can be location of satellite - which gives direction from location of base station to satellite. In some embodiments an indication of data in general need not be the data itself, but can be an identifier of the data or other data that enables a calculation of the data.

Such feedback will enable the user to almost instantaneously determine whether the base station 313 is blocked or not and in which directions.

In some embodiments, the feedback 250 includes textual information 250D providing information on the situation. Such textual information can inform a user that the station is blocked. For example STATION BLOCKED or STATION OK. In some embodiments, the direction of the blocking may also be part of the textual information. For example STATION BLOCKED NORTH.

In some embodiments the feedback 250 provided on the UE 200 includes an indication 250D of direction(s) that are to be disregarded.

In some embodiments the server (or the UE) is configured to retrieve a map of the operational area, from memory or from a cloud (or internet) service, and to include the map in the feedback 250. In cases where there is no map of the operational area, a map of the general area may be retrieved instead.

Figure 4B shows schematic views of an example embodiment where feedback 250 is provided visually on the display 230A of the UE 200 and where the feedback includes the map. The indication 250A of the position of the base station 313 is easily determined by determining the position of the base station 313. In some embodiments the base station 313 determines its position and forwards this. In some embodiments the server 340 determines the position of the base station 313 based on the received satellites, where in such embodiments information on the timing of the satellite signals are included. By providing the feedback 250 in combination with a map, the user will be able to ascertain almost directly what is blocking the base station 313 and where to best move the base station 313 by a simple glance at the map with feedback 250.

As is seen in figure 3B, as the user moves the base station 313 so that it is no longer blocked (to the left of the house in the figure), the base station 313 is no longer blocked and the feedback 250 provided indicates this as is shown in figure 4C.

In some embodiments the feedback comes with a recommendation. Such a recommendation can be determined based on the direction(s). For example if there are satellites received in a first direction, but not in a second direction, then the recommendation could be to move the base station in the direction of the received satellites. Alternatively, the recommendation could be to move the base station in a direction opposite from the first direction hoping to get past a blocking object. Alternatively, the recommendation could be to move the base station in a direction opposite from the second direction hoping to get past a blocking object.

In embodiments where a map of the operational (or general) is retrieved, the recommendation is based on an analysis of the map.

In some embodiments such analysis includes a topological analysis. Based on a topological analysis it can be determined if the base station 313 is placed in a location shadowed by natural structures, such as hills.

In some embodiments such analysis includes a feature analysis. Based on a feature analysis it can be determined if the base station 313 is placed in a location shadowed by features, such as trees or houses. In some embodiments the feature analysis is performed based on image analysis. In some embodiments, the feature analysis is performed based on features indicated in the map.

In some embodiments a recommended location may be determined based on such analysis. By analysing the map to determine if there is a location that is not shadowed by structures, such a position could be recommended.

In such embodiments, the feedback 250 includes an indication of the recommended position, in textual form or as a graphical indication relative the indication 250A of the location of the base station 313. The inventors have thus devised a concept where it may be ascertained quickly whether a base station 313 is positioned well, and to do this prior to any installation and/or training has been done.

Figure 5 shows a flowchart for a general method according to herein. The method is for use in a robotic work tool system as in figure 1 in a manner as discussed above in relation to figures 3 A, 3B, 4A and 4B. The method comprises a controller of the robotic work tool system receiving 510 zero or more satellites reliably received by a base station 313, comparing 520 to expected satellites and providing 530 feedback.

In some embodiments the controller is the controller 340A of the server 340.

In some embodiments the controller is the controller 210 of the UE 200. And in some embodiments the controller is the controller 210 of the UE 200 for performing some of the processing and the controller 340A of the server 340 for performing some of the processing.

In some embodiments, where the controller 340A is the controller of the server 340, the controller 340A is configured to receive the indication of zero or more reliably received satellites from the base station 313 and to receive the indication of expected satellites. The indication of expected satellites can be received from a memory 340B of the server 340 or from an external (cloud) service. As the indication of expected satellites and the indication of reliably received satellites are received, the controller is configured to compare the reliably received satellites to the list of expected satellites for determining if there are shadowed areas.

In some embodiments, which also applies to embodiments regardless of which controller performs the comparison or processing, an indication of data in general need not be the data itself, but can be an identifier of the data or other data that enables a calculation of the data.

In some embodiments, which also applies to embodiments regardless of which controller performs the comparison or processing, the indication can be a location of satellite, from which location a direction from the location of base station to the satellite can be determined.

In some embodiments, the controller 340A is further configured to provide the feedback 250 to be displayed on the User Equipment 200 by providing an indication of the direction of received satellites and/or missing satellites to the User Equipment, thereby causing the User Equipment 200 to generate the feedback 250 and display the feedback 250. For embodiments where the controller 340A of the server 340 is configured to perform the main processing, the controller 340A of the server thus only need to perform indications of the directions, and need not perform all the processing.

Figure 6 shows a schematic view of a computer-readable medium 600 carrying computer instructions 610 that when loaded into and executed by a controller of a computing device, such as a User Equipment 200 or a server 340, enables the computing device to implement the present invention. In the example of figure 6, the computing device will be exemplified as the UE 200- The computer-readable medium 600 may be tangible such as a hard drive or a flash memory, for example a USB memory stick or a cloud server. Alternatively, the computer-readable medium 600 may be intangible such as a signal carrying the computer instructions enabling the computer instructions to be downloaded through a network connection, such as an internet connection. In the example of figure 6, a computer-readable medium 600 is shown as being a hard drive or computer disc 600 carrying computer-readable computer instructions 610, being inserted in a computer disc reader 620. The computer disc reader 620 may be part of a cloud server 630 - or other server - or the computer disc reader 620 may be connected to a cloud server 630 - or other server. The cloud server 630 may be part of the internet or at least connected to the internet. The cloud server 630 may alternatively be connected through a proprietary or dedicated connection. In one example embodiment, the computer instructions are stored at a remote server 630 and be downloaded to the memory 220 of the User Equipment 200 for being executed by the controller 210.

The computer disc reader 620 may also or alternatively be connected to (or possibly inserted into) a User Equipment 200 for transferring the computer-readable computer instructions 610 to a controller of the User Equipment 200 (presumably via a memory of the User Equipment 200).

Figure 6 shows both the situation when a User Equipment 200 receives the computer-readable computer instructions 610 via a server connection and the situation when another User Equipment 200 receives the computer-readable computer instructions 610 through a wired interface. This enables for computer-readable computer instructions 610 being downloaded into a User Equipment 200 thereby enabling the User Equipment 200 to operate according to and implement the invention as disclosed herein.