SE545236C2

SE545236C2 - Problem handling of a robotic work tool

Info

Publication number: SE545236C2
Application number: SE2150994A
Authority: SE
Inventors: Carmine Celozzi; Henrik Eklund; Herman Jonsson; Jacob Malm; Micael Hafström
Original assignee: Husqvarna Ab
Priority date: 2021-08-12
Filing date: 2021-08-12
Publication date: 2023-05-30
Also published as: SE2150994A1; WO2023018364A1

Abstract

A method for use in a robotic work tool system (400) comprising a robotic work tool (200) connected to a robotic work tool controlling application, the robotic work tool (200) comprising a propulsion device, a navigation device (270, 280, 285), and a communication interface (203), wherein the communication interface (203) is configured to connect the robotic work tool to a user equipment configured to execute the robotic work tool controlling application, and wherein the method comprises: detecting a problem (510); transmitting (520) information regarding the problem to the robotic work tool controlling application; stopping operation (535) of the robotic work tool (200); executing an appropriate action (530) to alleviate (545) the problem; transmitting (555) data to the robotic work tool controlling application for confirming (560) that the problem is removed; receiving commands (565) and execute the commands to ensure (570) a good working condition and report (575) results to the robotic work tool controlling application; and in response thereto restarting (585) the robotic work tool (200) and continuing operation (590).

Description

PROBLEM HANDLING OF A ROBOTIC WORK TOOL TECHNICAL FIELD This application relates to robotic Work tools and in particular to a system and a method for providing an improved error handling for a robotic Work tool, such as a laWnmoWer.

BACKGROUND 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, the Work area is enclosed by a boundary With the purpose of keeping the robotic laWnmoWer inside the Work area. The Work area may also be limited by objects such as Walls or rocks. The boundary may be a physical boundary such as provided by a boundary Wire emitting a magnetic field that can be sensed by the robotic Work tool. Altematively, or additionally to the boundary Wire, many robotic Work tools are arranged to operate and navigate using a satellite navigation system, such as GNSS or GPS. The robotic Work tool may also or altematively be arranged to operate or navigate utilizing a beacon-based navigation system, such as UWB or RTK. In either case, the robotic Work tool may also be arranged to perform more or less advanced operating pattems, such as for example mowing a laWn so that a specific pattem in the grass is produced, such as When mowing a football field.

This requires that the navigation sensors, irrespective of type, are calibrated and in synch With the control of the propulsion of the robotic Work tool or the robotic Work tool may escape the Work area, or at least not be able to execute a desired operating pattem correctly.

Figure 1 shoWs a schematic view of an example of a typical Work area 105, being a garden, in Which a robotic Work tool 10, such as a robotic laWnmoWer, is set to operate.

The garden contains a number of obstacles, exempliﬁed herein by a number (2) of trees (T), a stone (S) 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 is enclosed by a boundary Wire 120 through Which a control signal 125 is transmitted by a signal generator 115 housed in a charging station 110, the control signal 125 generating a magnetic field that can be sensed by the robotic work tool 10. In this example the boundary wire 120 is laid so that so-called islands are forrned around the trees and the house. The garden also comprises or is in the line of sight of at least one signal navigation device 130. In this example the signal navigation device 130 is exemplified as a beacon, but it should be noted that it may also be any number of satellites. The use of satellite and/or beacon navigation enables for a boundary that is virtual, in addition to or as an altemative to the boundary wire 120. A virtual boundary 120" is indicated in figure 1 by the dotted line. From here on there will be made no difference between the boundary being defined by the boundary wire 120 or as a virtual boundary 120" and the boundary of the work area 105 will hereafter simply be referred to as the boundary 120, unless otherwise specifically mentioned. In the example of figure 1, the robotic work tool is set to operate according to a specific pattem P indicated by the dashed arrow in figure In order to control the robotic work tool more efficiently, the robotic work tool 10 may be connected to a user equipment 30, such as a smartphone, executing a robotic work tool control application. The robotic work tool control application receives information from the robotic work tool in order to provide updated status reports to an operator. The operator is also enabled to provide commands to the robotic work tool 10 through the robotic work tool controlling application. The commands may be for controlling the propulsion of the robotic work tool, to perform a specific operation or regarding scheduling of the robotic work tool°s operation.

During operation it may happen that one of the many sensors in the robotic work tool signals or senses that an error or otherwise unexpected situation has arisen and, in response thereto, sends a notification regarding this to the user equipment 30, such as through an error code. In response to the error being detected the operation of the robotic work tool 100 may be halted or stopped, by the robotic work tool on its own volition or by the user equipment 30 through the robotic work tool controlling application.

As the remote monitoring enables a user to be far away from the robotic work tool while still controlling the robotic work tool even during operation, the likelihood that an error code is issued when the operator is far away is increased. This in turn leads to that the down time due to an error becomes quite significant.

If the robotic work tool is operating as part of a service, this down time can have significant cost consequences.

Previous attempts at finding solutions for reducing such down time include assigning more than one robotic work tool to each work area, so that even if one robotic work tool is rendered inoperable, at least some servicing will be provided. This, however, increases the cost of a system two-fold.

Other attempts at finding solutions include categorizing the errors differently so that fewer error codes halt the operation. However, this may have serious consequences as concems safety standards.

Thus, there is a need for an improved manner of enabling a robotic work tool to continue operation even after an error has occurred.

SUMMARY The inventors have realized that by enabling an operator (application or user) to actually confirm that a problem has been overcome, the robotic work tool can be allowed to be restarted again and to continue operation for many problems - once alleviated.

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 comprising a robotic work tool connected to a robotic work tool controlling application, the robotic working tool comprising a propulsion device, a navigation device, a communication interface and a controller, wherein the communication interface is configured to connect the robotic work tool to a user equipment configured to execute the a robotic work tool controlling application, and wherein the controller is configured to: detect a problem; transmit information regarding the problem to the robotic work tool controlling application; stop operation of the robotic work tool; execute an appropriate action to alleviate the problem; transmit data to the robotic work tool controlling application for confirrning that the problem is removed; receive commands and execute the commands to ensure a good working condition and report results to the robotic work tool controlling application; and in response thereto restart the robotic Work tool and continue operation.

In some embodiments the information regarding the error indicates an error code.

In some embodiments the commands to ensure a good Working condition relates to a propulsion of the robotic Work tool, and Wherein the results indicate Whether the movement sensor provides sensor readings corresponding to the commands.

In some embodiments the further data includes readings of the movement sensor for ensuring Whether the movement sensor is operational.

In some embodiments the further data includes images for deterrnining Whether an obstacle is no longer present.

In some embodiments the controller is further configured to determine an error code for the detected problem and transmit the error code as the information regarding the problem.

In some embodiments the robotic Work tool controlling application is further configured to signal a success of alleviating the problem and receive a confirmation from an operator thereto.

In some embodiments the robotic Work tool controlling application is further conf1gured to determine the appropriate action.

In some embodiments the robotic Work tool controlling application is further configured to confirm the ensured good Working condition based on the reported results and in response thereto transmit commands to restart the robotic Work tool.

In some embodiments the robotic Work tool is configured for operating in a Work area comprising an uneven surface, Where objects are of a similar appearance to the surface and/or overhanging obstacles.

In some embodiments the robotic Work tool is a robotic laWnmoWer.

In some embodiments the robotic Work tool is arranged for indoor use. In some embodiments the robotic Work tool is a ﬂoor grinder. In some embodiments the robotic Work tool is a vacuum cleaner.

In some embodiments the robotic Work tool system further comprises the user equipment executing the robotic Work tool controlling application.

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 comprising a robotic Work tool connected to a robotic Work tool controlling application, the robotic Work tool comprising a propulsion device, a navigation device, and a communication interface, Wherein the communication interface is conf1gured to connect the robotic Work tool to a user equipment configured to execute the robotic Work tool controlling application, and Wherein the method comprises: detecting a problem; transmitting information regarding the problem to the robotic Work tool controlling application; stopping operation of the robotic Work tool; executing an appropriate action to alleviate the problem; transmitting data to the robotic Work tool controlling application for confirrning that the problem is removed; receiving commands and execute the commands to ensure a good Working condition and report results to the robotic Work tool controlling application; and in response thereto restarting the robotic Work tool and continuing operation.

In some embodiments the method comprises detecting a problem that the robotic Work tool is trapped, by detecting that the robotic Work tool is not able to move out of an area of a size smaller than the Work area in a time period and executing an appropriate action to alleviate the problem by maneuvering the robotic Work tool based on the data transmitted, the data transmitted comprising images and/or other sensor readings of the surroundings of the area.

In some embodiments the method comprises detecting a problem that the robotic Work tool is unable to enter a charging station, by detecting that the robotic Work tool is not able to move in to the charging station and executing an appropriate action to alleviate the problem by detecting an object blocking the entrance of the charging station based on the data transmitted, the data transmitted comprising images and/or other sensor readings of the entrance of the charging station and in response thereto maneuvering the robotic Work tool so that it pushes the object from a side of the charging station.

In some embodiments the method comprises detecting a problem that the robotic Work tool is unable to climb a slope, by detecting that the robotic Work tool is not able to unable to continue on a trajectory despite no collision being detected and executing an appropriate action to alleviate the problem by maneuvering the robotic Work tool so that another path is attempted based on the data transmitted, the data transmitted comprising images and/or other sensor readings of the slope and/or the robotic work tool°s status.

In some embodiments the method comprises detecting a problem that the robotic work tool is slipping, by detecting that the robotic work tool is not able to unable to continue on a trajectory despite no collision being detected and executing an appropriate action to alleviate the problem by maneuvering the robotic work tool so that another path is attempted based on the data transmitted, the data transmitted comprising images and/or other sensor readings of the surroundings and/or the robotic work tool"s status.

In some embodiments the method comprises detecting a problem that the robotic work tool is unable to change a cutting height, by detecting that the height of a cutting tool of the robotic work tool is not changing and executing an appropriate action to alleviate the problem by continue operating of the robotic work tool at a current cutting height.

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 l shows an example of a robotic work tool system being a robotic lawnmower system; Figure 2A shows an example of a robotic lawnmower according to some embodiments of the teachings herein; Figure 2B 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 3 shows an example of a computing device according to some embodiments of the teachings herein; Figure 4 shows a schematic view of a robotic work tool system 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 farrning equipment, or other robotic work tools where a work tool is to be safeguarded against from accidentally extending beyond or too close to the edge of the robotic work tool.

Figure 2A shows a perspective view of a robotic work tool 200, here exemplified by a robotic lawnmower 200, having a body 240 and a plurality of wheels 230 (only one side is shown). The robotic work tool 200 may be a multi-chassis type or a mono-chassis type (as in figure 2A). 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 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 ﬂoor grinders, robotic ﬂoor cleaners to mention a few examples where a work tool should be kept away from the edges for safety or convenience concerns.

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 predeterrnined).

Figure 2B shows a schematic overview of the robotic work tool 200, also exemplified here by a robotic lawnmower 200. In this example embodiment the robotic lawnmower 200 is of a mono-chassis type, having a main body part 240. The main body part 240 substantially houses all components of the robotic lawnmower 200. The robotic lawnmower 200 has a plurality of wheels 230. In the exemplary embodiment of figure 2B the robotic lawnmower 200 has four wheels 230, two front wheels and two rear wheels. At least some of the wheels 230 are driveable connected to at least one electric motor 250. It should be noted that even if the description herein is focused on electric motors, combustion engines may altematively be used, possibly in combination with an electric motor. In the example of figure 2B, each of the wheels 230 is connected to a common or to a respective electric motor 255 for driving the wheels 230 to navigate the robotic lawnmower 200 in different manners. The wheels, the motor 255 and possibly the battery 250 are thus examples of components making up a propulsion device. By controlling the motors 250, the propulsion device may be controlled to propel the robotic lawnmower 200 in a desired manner, and the propulsion device will therefore be seen as synonymous with the motor(s) The robotic lawnmower 200 also comprises a controller 2l0 and a computer readable storage medium or memory 220. The controller 2l0 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 220 to be executed by such a processor. The controller 2l0 is conf1gured to read instructions from the memory 220 and execute these instructions to control the operation of the robotic lawnmower 200 including, but not being limited to, the propulsion and navigation of the robotic lawnmower.

The controller 210 in combination With the electric motor 255 and the Wheels 230 forrns the base of a navigation system (possibly comprising further components) for the robotic laWnmoWer, enabling it to be self-propelled as discussed under figure 2A, The controller 210 may be implemented using any suitable, available processor or Programmable Logic Circuit (PLC). The memory 220 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 200 is further arranged With a Wireless communication interface 215 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 is specifically arranged to communicate With a user equipment 300 as discussed in relation to figure 3 below for providing information regarding status, location, and progress of operation to the user equipment 300 as Well as receiving commands or settings from the user equipment The robotic laWnmoWer 200 also comprises a grass cutting device 260, such as a rotating blade 260 driven by a cutter motor 265. The grass cutting device being an example of a Work tool 260 for a robotic Work tool 200. As a skilled person Would understand the cutter motor 265 is accompanied or supplemented by various other components, such as a drive shaft to enable the driving of the grass cutting device, taken to be understood as included in the cutter motor 265. The cutter motor 265 Will therefore be seen as representing a cutting assembly 265 or in the case of another Work tool, a Work tool assembly The robotic laWnmoWer 200 may further comprises at least one navigation sensor, such as an optical navigation sensor, an ultrasound sensor, a beacon navigation sensor and/or a satellite navigation sensor 285. The optical navigation sensor may be a camera-based sensor and/or a laser-based sensor. The beacon navigation sensor 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.

Altematively, or additionally, the beacon navigation sensor may be an optical receiver configured to receive signals from an optical beacon. The satellite navigation sensor may be a GPS (Global Positioning System) device or other Global Navigation Satellite System (GNS S) device. In embodiments, Where the robotic laWnmoWer 200 is arranged With a navigation sensor, the magnetic sensors 270 as Will be discussed below are optional. In embodiments relying (at least partially) on a navigation sensor, the Work area may be specified as a virtual Work area in a map application stored in the memory 220 of the robotic laWnmoWer 200. The virtual Work area may be defined by a virtual boundary.

In the examples that Will be discussed herein the navigation sensor is a satellite navigation sensor, such as GPS, GNSS or a supplemental satellite navigation sensor such as RTK.

The robotic laWnmoWer 200 may also or altematively comprise deduced reckoning sensors 280. 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 200 to navigate With reference to a boundary Wire emitting a magnetic field caused by a control signal transmitted through the boundary Wire, the robotic laWnmoWer 200 is, in some embodiments, further configured to have at least one magnetic field sensor 270 arranged to detect the magnetic field and for detecting the boundary Wire and/or for receiving (and possibly also sending) information to/ from a signal generator (Will be discussed With reference to figure 1). In some embodiments, the sensors 270 may be connected to the controller 210, possibly via filters and an amplifier, and the controller 210 may be configured to process and evaluate any signals received from the sensors 270. The sensor signals are caused by the magnetic field being generated by the control signal being transmitted through the boundary Wire. This enables the controller 210 to determine Whether the robotic laWnmoWer 200 is close to or crossing the boundary Wire, or inside or outside an area enclosed by the boundary Wire. ll As mentioned above, in some embodiments, the robotic lawnmower 200 is arranged to operate according to a map of the Work area 205 (and possibly the surroundings of the Work area 205) stored in the memory 220 of the robotic lawnmower 200. The map may be generated or supplemented as the robotic lawnmower 200 operates or otherwise moves around in the Work area The robotic Work tool 200 ma also comprise additional sensors 290 for enabling operation of the robotic Work tool 200, such as Visual sensors (for example a camera), or ranging sensors.

Figure 3 shows a schematic view of a computing device 300 according to an embodiment of the present invention. In some embodiments the computing device is a user equipment such as a smartphone, smartwatch or a tablet computer. The user equipment 300 comprises a controller 30l a memory 302 and a user interface 3 l It should be noted that the user equipment 300 may comprise a single device or may be distributed across several devices and apparatuses. In some embodiments the computing device is a server device.

The controller 30l is conf1gured to control the overall operation of the user equipment 300 and specifically to execute a robotic Work tool controlling application. In some embodiments, the controller 30l is a specific purpose controller. In some embodiments, the controller 30l is a general-purpose controller. In some embodiments, the controller 30l is a combination of one or more of a specific purpose controller and/or a general-purpose controller. As a skilled person Would understand there are many altematives for hoW to implement a controller, such as using Field - Programmable Gate Arrays circuits, ASIC, GPU, NPU etc. in addition or as an altemative. For the purpose of this application, all such possibilities and altematives Will be referred to simply as the controller 30l.

The memory 302 is configured to store data such as application data, settings and computer-readable instructions that When loaded into the controller 30l indicates how the user equipment 300 is to be controlled. The memory 302 is also specifically for storing the robotic Work tool controlling application and data associated thereWith. The memory 302 may comprise several memory units or devices, but they Will be perceived as being part of the same overall memory 302. There may be one memory unit for therobotic Work tool controlling application storing instructions and application data, one memory unit for a display arrangement storing graphics data, one memory for the communications interface 303 for storing settings, and so on. As a skilled person Would understand there are many possibilities of how to select Where data should be stored and a general memory 302 for the user equipment 300 is therefore seen to comprise any and all such memory units for the purpose of this application. As a skilled person Would understand there are many altematives of hoW to implement a memory, for example using non-volatile memory circuits, such as EEPROM memory circuits, or using volatile memory circuits, such as Robotic Work tool memory circuits. For the purpose of this application all such altematives Will be referred to simply as the memory In some embodiments the user equipment 300 further comprises a communication interface 303. The communications interface 303 is configured to enable the user equipment 300 to communicate With robotic Work tools, such as the robotic Work tool of figures 2A and 2B.

The communication interface 303 may be Wired and/or Wireless. The communication interface 303 may comprise several interfaces.

In some embodiments the communication interface 303 comprises a radio frequency (RF) communications interface. In one such embodiment the communication interface 303 comprises a BluetoothTM interface, a WiFiTM interface, a ZigBeeTM interface, a RFIDTM (Radio Frequency IDentif1er) interface, Wireless Display (WiDi) interface, Miracast interface, and/or other RF interface commonly used for short range RF communication. In an altemative or supplemental such embodiment, the communication interface 303 comprises a cellular communications interface such as a f1fth generation (5 G) cellular communication interface, an LTE (Long Term Evolution) interface, a GSM (Global Systeme Mobile) interface and/or other interface commonly used for cellular communication. In some embodiments the communication interface 303 is configured to communicate using the UPnP (Universal Plug n Play) protocol. In some embodiments the communication interface 303is configured to communicate using the DLNA (Digital Living Network Appliance) protocol.

In some embodiments, the communication interface 303 is configured to enable communication through more than one of the example technologies given above. Thecommunications interface 303 may be configured to enable the user equipment 300 to communicate with other devices, such as other smartphones.

The user interface 310 comprises one or more output devices and one or more input devices. Examples of output devices are a display arrangement, such as a display screen 310-1, one or more lights (not shown in ﬁgure 1A) and a speaker (not shown). Examples of input devices are one or more buttons 310-2 (virtual 310-2A or physical 310-2B), a camera (not shown) and a microphone (not shown). In some embodiments, the display arrangement comprises a touch display 310-1 that act both as an output and as an input device being able to both present graphic data and receive input through touch, for example through virtual buttons 310-2A.

Figure 4 shows a robotic work tool system 400 in some embodiments. The schematic view is not to scale. The robotic work tool system 400 of ﬁgure 4, corresponds in many aspects to the robotic work tool system 100 of figure 1, except that the robotic work tool system 400 of figure 4 comprises a robotic work tool 200 according to the teachings herein. It should be noted that the work area shown in figure 4 is simplified for illustrative purposes but may contain some or all of the features of the work area of figure 1, and even other and/or further features as will be hinted at below.

As with figures 2A and 2B, the robotic work 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 work tools adapted to operate within a work area.

The robotic work tool system 400 comprises a charging station 410 which in some embodiments is arranged with a signal generator (not shown) for providing a control signal through a boundary wire 420. As an electrical signal is transmitted through a wire, such as the control signal being transmitted through the boundary wire 420, a magnetic field is generated. The magnetic field may be detected using field sensors, such as Hall sensors. A sensor -in its simplest form -is a coil surrounding a conductive core, such as a ferrite core. The amplitude of the sensed magnetic field is proportional to the derivate of the control signal. A large variation (fast and/or of greatmagnitude) results in a high amplitude for the sensed magnetic field. As mentioned above, the actual boundary wire is optional and the boundary 420 may be virtual, stored in a map application. The robotic work tool system 400 may comprise or be arranged to utilize at least one signal navigation device 430. In the example of figure 4 two options are shown, a first being at least one satellite 43 0A (only one shown, but it should be clear that a minimum of three are needed for an accurate three 2-dimensional location). The second option being at least one beacon, such as an RTK beacon 43 0B (only one shown).

The work area 405 is in this application exemplified as a garden, but can also be other work areas as would be understood. As hinted at above, the garden may contain a number of obstacles, for example a number of trees, stones, slopes and houses or other structures.

In some embodiments the robotic work tool is arranged or configured to traverse and operate in a work area that is not essentially ﬂat, but contains 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 altematively arranged or conf1gured to traverse and operate in a work area that contains obstacles that are not easily discemed 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 altematively arranged or conf1gured 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 405 exemplified with referenced to figure 4, may thus be such a non-uniforrn work area as disclosed in this paragraph that the robotic work tool is arranged to traverse and/or operate in.

The robotic work tool system 400 also comprises or is arranged to be connected to a user equipment 300, such as a user equipment 300 of figure 3. In some embodiments the robotic work tool 200 is arranged to be connected to the user equipment 300 directly and in some embodiments the robotic Work tool 200 is arranged to be connected to the user equipment 300 indirectly through the charging station 410. As discussed above the user equipment 300 is configured to execute a robotic Work tool controlling application that receives information from the robotic Work tool 200 and is able to provide commands to the robotic Work tool 200. The user equipment 300 is specifically arranged to receive an error code EC, possibly along With status data regarding the error code. The user equipment 300 is also specifically arranged to send a command C to the robotic Work tool 200 for causing the robotic Work tool 200 to perform an action, such as controlling the propulsion of the robotic Work tool 200, to execute an operating pattem, to request a sensor reading, or other commands.

The robotic Work tool system 400 may altematively or additionally comprise or be arranged to be connected to a server application, such as a cloud server application 440. The connection to the server application 440 may be direct from the robotic Work tool 200, direct from the user equipment, indirect from the robotic Work tool 200 via the charging station, and/or indirect from the robotic Work tool 200 via the user equipment In the below several embodiments of how the robotic Work tool 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.

Figure 5 shoWs a ﬂoWchart for a general method according to herein. The method is for use in a robotic Work tool as in figures 2A and 2B. The improved manner for handling error codes as discussed herein Will be discussed With simultaneous reference to figure 4 and figure As the robotic Work tool 200 encounters or detects 510 a problem, an error code EC is deterrnined 515 for the problem detected and transmitted 520 to the user equipment 300. The error code EC may be transmitted along With additional data regarding the problem, such as location. The error code EC is matched against a table indicating What the appropriate action should be, and an appropriate action is thereby deterrnined 525. In some embodiments, the robotic Work tool 200 is configured to determine the appropriate action. In some embodiments, the user equipment is configured to determine the appropriate action. And in some embodiments, the serverapplication 440 is conf1gured to determine the appropriate action. In a combination of two or more of these embodiments, one unit may be configured to determine the appropriate action for some error codes, possibly in some combinations with the additional data, whereas a second unit is configured to determine the appropriate action for some other error codes, possibly in some combinations with the additional data. A unit is here the robotic work tool 200, the user equipment 300, the server application 440 or manually by the operator. It may thus differ exactly what information regarding the error that is transmitted to the robotic work tool controlling application depending on which unit makes which deterrnination.

The appropriate action is executed 530 by the robotic work tool 200. In case the appropriate action includes 535 to stop or otherwise halt the operation of the robotic work tool 200, it may (optionally as indicated by dashed lines) be deterrnined 540 by a unit whether the error code is of a type that allows remote restart.

The robotic work tool 200 perforrns the appropriate action(s) to alleviate 545 the detected problem, and if successful this is signalled 550 or otherwise indicated. In some embodiments this is signalled to the user equipment 300. The user equipment may convey information regarding this through its user interface 304. The information may include that a restart is possible. Altematively, possibly for some error types, the user equipment analyses the situation and the received data.

However, as has been realized by the inventors and brieﬂy touched upon above, contemporary robotic work tools 200 are arranged to perform complicated operations and to navigate according to virtual boundaries. It is thus - as the inventors have realized through inventive reasoning - important to ensure that all navigation sensors (and other sensors) are working correctly before allowing the robotic work tool 200 to continue operation.

The user equipment 300 is therefore configured to receive 555 further sensor data from the robotic work tool 200. In case the problem related to an extemal cause (such as a blocking obstacle for example a passing child), the further sensor data may include sensor data for example in the form of images from a camera (part of the further sensor(s) 290). Altematively or additionally, the further data may include other sensor data as well. In some embodiments the further data includes data from after the problemarise, in some embodiments, the further data includes data from before the problem arose, and in some embodiments, the further data includes data from When the problem arose. Based on the further data (partially or completely, it may be deterrnined 560 that the obstacle has been removed or at least is no longer present, i.e. When it is confirmed that the problem is removed. The deterrnination may be performed by the controller 301 of the user equipment automatically. Altematively, or additionally the deterrnination may be performed by the operator of the user equipment 300. In case the problem relates to an intemal problem the further sensor data may include sensor data indicating that the intemal problem is alleviated. For example, if the problem Was related to a loss of navigation signal (such as a loss of reception of magnetic control signal from the boundary Wire 320), the further sensor data may include sensor readings from the magnetic field sensors 270 indicating that the signal is again received successfully, i.e. When the sensor is operational. It may thus be deterrnined from the 560 from the further sensor data that the problem is no longer present, i.e. When it is confirmed that the problem is removed.

As it is confirmed 560 that the problem is no longer present, the robotic Work tool 200 receives commands 565 from the user equipment 300 for example for ensuring 570 that other sensors are in synch and/or operating appropriately. The commands may be given by an operator, and/or by the controller 301 of the user equipment as instructed by the robotic Work tool controlling application.

The commands may relate to movement commands for ensuring that movement sensors (such as the deduced reckoning sensors 280 and/or the satellite navigation sensors 285) are in synch With the various propulsion commands that are given.

The commands are therefore for ensuring 570 that the robotic Work tool 200 is in good Working condition. The result of the commands is reported back 575 to the user equipment 300, Whereupon the results are confirmed 580 by the operator and/or the robotic Work tool controlling application. The confirrnation may be done manually by the operator. Altematively, or additionally the confirrnation is made automatically by the robotic Work tool controlling application. In some embodiments, the operator manually confirrns some conditions (the more critical ones) and the robotic Work tool controlling application confirrns some conditions (the less critical ones). The results areconfirrned if the sensor readings correspond to the commands. For example, if the commands relate to a movement or other propulsion of the robotic Work tool 200, the movement sensors, such as the magnetic field sensors, the deduced reckoning sensor and/or the satellite navigation sensor 285 should provide a sensor reading that corresponds to the movement command.

In some embodiments, the provision of commands and the reporting of results may be achieved by the operator opening a video-stream from the camera(s) 290 via the robotic Work tool controlling application. If the issue that prevents the robotic Work tool to continue to operate is due to a situation and/or obstacle Which the robotic Work tool cannot solve on its own, the operator can utilize the information from the camera(s), possibly supported by other depth sensors, and give movement commands through the user interface 304 of the user equipment. Such movement commands may be given by clicking left/right/forward/reverse arroWs for short movements on the display 304-1. Altematively, or in combination, Waypoint(s) may be defined by clicking on the display, possibly Where feedback is presented such as in a digital map. The Way points may be used to indicate how the robotic Work tool 200 should navigate. Altematively, the operator can estimate the obstacle and deﬁne a type (e. g. What distance should the robotic Work tool keep to the obstacle), update a site plan (i.e a map of the Work area) With obstacle data accordingly and let a route planning system of the robotic Work tool 200 update the planned path. In doing so, and by also always prioritizing avoidance by the on-board direct collision sensors, the robotic Work tool can (possibly) be safely navigated out of a complex situation remotely Without need for loW-latency uninterrupted communication With the robotic Work tool Which Would be the case With a j oystick for controlling the operation of the robotic Work tool As they are confirmed, the robotic Work tool 200 is restarted 585 and continues its operation It should be noted that although the description above is focussed on the robotic Work tool being connected to a user equipment, the robotic Work tool may in some embodiments be connected to a server, for example a cloud server or a dedicated backoff1ce server. The server is such embodiments configured to execute the robotic Work tool controlling application. The user of the user equipment may then be anoperator of the server. Altematively or additionally, in some embodiments the user equipment is configured to connect to the server for passing on data and commands between the server and the robotic work tool. Altematively or additionally, in some embodiments the user equipment is configured to connect to the server for passing on data and commands between the server and the robotic work tool and wherein the robotic work tool controlling application is executed by both the user equipment and the server jointly. In the embodiments disclosed in regards to the server, the components shown in figure 3 as relating to the user equipment, thus also apply to a server.

In the below some problems that may arise and how to overcome them will be discussed.

In one problem, the mower has become trapped, which may be detected by detecting that the robotic work tool has not moved away from an area of a size smaller than the work area (for example 2x2 m) for a time period (for example l, 2, 5, l0, 12 or in the range of l to 15, l to l0 or l to 5 minutes). The problem can be overcome by providing a user (or automatic operator) with a video feed and/or other data which enables a view or map of the surroundings to be generated. Based on the view or map, commands may be given (manually by user or automatically by robotic work tool controlling application) for manoeuvring the robotic work tool out of the area based on the view or map. The deterrnination that the robotic work tool is no longer trapped may be based on the images and/or other sensor data for deterrnining that the robotic work tool is able to move freely outside the area.

In another problem the robotic work tool is unable to enter the charging station. The robotic work tool can then provide images and/or other sensor data of the entrance to the charging station to the robotic work tool controlling application. Based on the images and/or other sensor data of the entrance to the charging station the robotic work tool application or the user of the robotic work tool controlling application, can determine if an object (such as a branch or twig) is blocking the entrance, and if so, manoeuvre the robotic work tool so that it perhaps can push the object from the side so that it no longer blocks the entrance. The data to confirm that the entrance is no longer blocked may again be images and/or other sensor data of the entrance to the charging station.

In another problem the robotic Work tool is unable to continue a current traj ectory Without any collision being detected. The robotic Work tool may transmit data regarding its inclination to the robotic Work tool, such data may be based on accelerometer and/or images from Which it may be deterrnined that the robotic Work tool is attempting to go up a hill or slope, that is simply too steep (perhaps due to Wet surface). The robotic Work tool application or the user of the robotic Work tool application may then manoeuVre the robotic Work tool so that an altemate route up the slope or around the slope is attempted. The results may be based on sensor data such as relating to the incline, the position and or the speed of the robotic Work tool, being examples of the status of the robotic Work tool, as Well as on images showing the position of the robotic Work tool in relation to the slope. Similar operations are performed When it is detected that the robotic Work tool is slipping an unable to continue on a trajectory Wherein sensor data on the surroundings is transmitted.

In another problem the robotic Work tool is unable to change the cutting height. This may be detected based on the cutting height not being changed. The problem can be (temporarily) oVercome by simply continue operating With the already set cutting height, thereby trading possible marks for an uninterrupted operation.

Claims

1. A robotic Work tool system (400) comprising a robotic Work tool (200) connected to a robotic Work tool controlling application, the robotic Work tool (200) comprising a propulsion device, a navigation device (270, 280, 285), a communication interface (203) and a controller, Wherein the communication interface (203) is configured to connect the robotic Work tool to a user equipment configured to eXecute a robotic Work tool controlling application, and Wherein the controller is configured to: detect a problem (510); transmit (520) information regarding the problem to the robotic Work tool controlling application; stop operation (535) of the robotic Work tool (200); eXecute an appropriate action (530) to alleviate (545) the problem; transmit (555) data to the robotic Work tool controlling application for confirming (560) that the problem is removed; receive commands (565) and eXecute the commands to ensure (570) a good Working condition and report (575) results to the robotic Work tool controlling application; and in response thereto restart (585) the robotic Work tool (200) and continue operation (590), Wherein the robotic Work tool is further configured to ensure (570) the good Working condition by ensuring that the navigation device (270, 280, 285) is Working correctly Wherein the commands relate to movement commands for ensuring that movement sensors are in synch With the movement commands and Wherein »§š~*=.e»»further data includes readings of the movement sensor (270, 280, 285) for ensuring Whether the movement sensor is operational.

2. The robotic Work tool system (400) according to claim 1, Wherein the information regarding the “ gggvindicates an error code.

3. The robotic Work tool system (400) according to claim 1 or 2, Wherein the commands to ensure a good Working condition relates to a propulsion of the robotic Work tool (200), and Wherein the results indicate Whether the movement sensor (270, 280, 285) provides sensor readings corresponding to the commands.

4. The robotic Work tool system (400) according to any preceding claim, Wherein the further data includes images for determining Whether an obstacle is no longer present.

5. The robotic Work tool system (400) according to any preceding claim, Wherein the controller is further configured to determine an error code for the detected problem and transmit the error code as the information regarding the problem.

6. The robotic Work tool system (400) according to any preceding claim, Wherein the robotic Work tool controlling application is further configured to signal (550) a success of alleviating the problem and receive (560) a confirrnation from an operator thereto.

7. The robotic Work tool system (400) according to any preceding claim, Wherein the robotic Work tool controlling application is further configured to determine (525) the appropriate action.

8. The robotic Work tool system (400) according to any preceding claim, Wherein the robotic Work tool controlling application is further configured to confirm (580) the ensured (570) good Working condition based on the reported (575) results and in response thereto transmit commands to restart (585) the robotic Work tool (200).

9. The robotic Work tool system (400) according to any previous claim, Wherein the robotic Work tool is configured for operating in a Work area comprising an unevensurface, Where objects are of a similar appearance to the surface and/or overhanging ob stacles.

10. The robotic Work tool system (400) according to any previous claim, Wherein the robotic Work tool is a robotic 1aWnmoWer.

11. The robotic Work tool system (400) according to any of claims 1 to 8, Wherein the robotic Work tool is arranged for indoor use.

12. The robotic Work tool system (400) according to claim 11, Wherein the robotic Work tool is a ﬂoor grinder.

13. The robotic Work tool system (400) according to claim 11, Wherein the robotic Work tool is a vacuum cleaner.

14. The robotic Work tool system (400) according to any previous claim, further comprising the user equipment (300) eXecuting the robotic Work tool controlling application.

15. A method for use in a robotic Work tool system (400) comprising a robotic Work tool (200) connected to a robotic Work tool controlling application, the robotic Work tool (200) comprising a propulsion device, a navigation device (270, 280, 285), and a communication interface (203), Wherein the communication interface (203) is configured to connect the robotic Work tool to a user equipment configured to eXecute the robotic Work tool controlling application, and Wherein the method comprises: detecting a problem (510); transmitting (520) information regarding the problem to the robotic Work tool controlling application; stopping operation (535) of the robotic Work tool (200); eXecuting an appropriate action (530) to alleviate (545) the problem;transmitting (555) data to the robotic Work tool controlling application for confirrning (560) that the problem is removed; receiving commands (565) and eXecute the commands to ensure (570) a good Working condition and report (575) results to the robotic Work tool controlling application; and in response thereto restarting (585) the robotic Work tool (200) and continuing operation (590), characterized in that the method further comprises ensuring (570) the good Working condition by ensuring that the navigation device (270, 280, 285) is Working correctly Wherein the commands relate to movement commands for ensuring that movement sensors are in synch With the movement commands and Wherein the further data includes readings of the movement sensor (270, 280, 285) for ensuring Whether the movement sensor is operational.

16. The method according to claim 15, Wherein the method comprises detecting a problem (510) that the robotic Work tool is trapped, by detecting that the robotic Work tool is not able to move out of an area of a size smaller than the Work area in a time period and eXecuting an appropriate action (530) to alleviate (545) the problem by maneuvering the robotic Work tool based on the data transn1itted, the data transmitted comprising images and/or other sensor readings of the surroundings of the area.

17. The method according to claim 15 or 16, Wherein the method comprises detecting a problem (510) that the robotic Work tool is unable to enter a charging station, by detecting that the robotic Work tool is not able to move in to the charging station and eXecuting an appropriate action (530) to alleviate (545) the problem by detecting an object blocking the entrance of the charging station based on the data transmitted, the data transmitted comprising images and/or other sensor readings of the entrance of the charging station and in response thereto maneuvering the robotic Work tool. so that it pushes the object from a side of the charging station.

18. The method according to c1aim 15, 16, or 17, Wherein the method comprises detecting a prob1em (510) that the robotic Work too1 is unable to c1imb a s1ope, by detecting that the robotic Work too1 is not able to unable to continue on a trajectory despite no co11ision being detected and eXecuting an appropriate action (530) to a11eViate (545) the prob1em by maneuvering the robotic Work too1 so that another path is attempted based on the data transn1itted, the data transmitted comprising images and/or other sensor readings of the s1ope and/or the robotic Work too1”s status.

19. The method according to c1aim 15, 16, 17, or 18, Wherein the method comprises detecting a prob1em (510) that the robotic Work too1 is s1ipping, by detecting that the robotic Work too1 is not ab1e to unab1e to continue on a trajectory despite no co11ision being detected and eXecuting an appropriate action (530) to a11eViate (545) the prob1em by maneouvering the robotic Work too1 so that another path is attempted based on the data transn1itted, the data transmitted comprising images and/or other sensor readings of the surroundings and/or the robotic Work too1°s status.

20. The method according to c1aim 15, 16, 17, 18, or 19, Wherein the method comprises detecting a prob1em (510) that the robotic Work too1 is unab1e to change a cutting height, by detecting that the height of a cutting too1 (160) of the robotic Work too1 is not changing and eXecuting an appropriate action (530) to a11eViate (545) the prob1em by continue operating of the robotic Work too1 at a current cutting height.