Abstract:
An autonomous working device, in particular an autonomous lawn mower, comprising a computing unit. The autonomous working device is configured to cover a surface to be treated in strips. The computing unit is configured to adjust an overlap of the strips according to at least one parameter.

Description:
This application is a 35 U.S.C. §371 National Stage Application of PCT/EP2012/063882, filed on Jul. 16, 2012, which claims the benefit of priority to Serial No. DE 10 2011 082 416.2, filed on Sep. 9, 2011 in Germany, the disclosures of which are incorporated herein by reference in their entirety. 
     BACKGROUND 
     An autonomous working device, in particular an autonomous lawnmower, which comprises a computing unit and is provided for traveling in strips along a surface to be processed has already been proposed. 
     SUMMARY 
     The disclosure is based on an autonomous working device, in particular on an autonomous lawnmower, which comprises a computing unit and is provided for traveling in strips along a surface to be processed. 
     It is proposed that the computing unit be provided for setting an overlap of the strips as a function of at least one parameter. An “autonomous working device” is to be understood in this context as meaning, in particular, a device which at least partially automatically performs work such as, in particular, starts automatically, ends automatically and/or automatically selects at least one parameter such as, in particular, a distance parameter and/or a reversal point etc. The device is particularly preferably provided for traveling along a surface and performing work on this surface. In this context, various autonomous working devices which appear appropriate to a person skilled in the art are conceivable, such as, for example, an autonomous sweeping machine, an autonomous vacuum cleaner or an autonomous swimming bath cleaning machine etc., in particular, the autonomous working device is, however, formed by an autonomous lawnmower. In addition, a “computing unit” is to be understood as meaning, in particular, a unit having an information input, an information processing means and/or an information output. The computing unit advantageously has at least one processor, one memory, input and output means, further electrical components, one operating program, closed-loop control routines, open-loop control routines and/or calculation routines. The components of the computing unit are preferably arranged on a common circuit board and/or are advantageously arranged in a common housing. The computing unit is preferably arranged inside part of the autonomous working device which is moved in order to perform work, while being driven over the surface to be processed. However, alternatively and/or additionally, the computing unit could also be arranged outside the part of the autonomous working device such as, for example, in a remote control means and/or a fixed station. A connection between the part and the computing unit of the autonomous working device can be made, in particular, via a wireless connection. As a result, in particular the computing unit of the autonomous working device can be exported out of the part of the autonomous working device in order to keep loading by dirt low. In addition, as a result the weight of the part of the autonomous working device can be kept low. A “surface to be processed” is to be understood in this context as meaning, in particular, a surface which defines a working area. An “overlap” is to be understood in this context as meaning, in particular, a width of a surface which defines an overlapping region of two strips which run at least approximately parallel to one another. In addition, an overlap in the case of a constant strip width can also be defined by a difference between a strip width and a relative distance between two strips. A “relative distance between two strips” is to be understood in this context as meaning, in particular, a distance between the center lines of the strips. A “parameter” is to be understood in this context as meaning, in particular, at least one value which defines at least one characteristic property and/or a characteristic variable and/or an influencing variable. 
     The configuration of the autonomous working device according to the disclosure can particularly advantageously implement an efficient and effective working step of the autonomous working device. 
     The computing unit can preferably be provided for adapting a speed and/or a torque of a working unit of the autonomous working device as a function of the overlap. As a result, it is advantageously possible in the case of a large overlap to increase a speed, and in the case of a small overlap to reduce a speed. In addition, it would also be conceivable to adapt a speed and/or a torque by means of further parameters which are required for calculating an overlap. 
     It is also proposed that the computing unit be provided for setting the overlap in a differentiated fashion for various partial regions and/or for various strips of the surface to be processed. The partial region preferably has at least one approximately constant parameter. As a result, a surface to be processed can advantageously be processed in a differentiated fashion with respect to the overlap in order to achieve maximum efficiency. 
     The computing unit is preferably provided for setting the overlap of a strip as a function of at least one specific parameter of the corresponding strip. In this context, a “specific parameter” is to be understood as meaning, in particular, a parameter which can change from one strip to another strip but remains at least approximately the same over a corresponding strip. As a result, an overlap with individual strips can advantageously be adapted to the respective strip. 
     In addition it is proposed that the computer unit be provided for taking into account at least one strip length parameter. A “strip length parameter” is to be understood in this context as meaning, in particular, a parameter which represents directly or indirectly a characteristic variable for a strip length and/or preferably directly or indirectly allows an expected strip length to be inferred and/or is preferably formed by the expected strip length. In this context, an “expected strip length” is to be understood here as meaning, in particular, a strip length which the autonomous working device travels along without incidents which are unforeseen for the working device, such as, for example, an unknown obstacle, on the surface to be processed. A “strip length” is to be understood in this context as meaning, in particular, a length of a magnitude which the working device travels along without a significant change in direction. In this context, “without a significant change in direction” is to be understood as meaning, in particular, a change in direction by less than 10°, preferably by less than 5° and particularly preferably by less than 2°. As a result, a strip-specific parameter can advantageously be taken into account, as a result of which an overlap can be appropriately and efficiently adapted. 
     In this context it is conceivable, in particular, that the computing unit is provided for setting a larger overlap in the case of an expected long strip length than in the case of an expected short strip length. As a result, by means of the expected long strip length it is possible to ensure that the surface is completely processed up to the nearest strip. In the case of an expected short strip length it is therefore possible, in particular, to keep processing time short and loading of the surface to be processed low. 
     Furthermore, it is proposed that the computing unit be provided for taking into account at least one underlying surface parameter. An “underlying surface parameter” is to be understood in this context as meaning, in particular, a parameter which depends at least on a quality and/or a property of the underlying surface. Various qualities and/or properties which appear appropriate to a person skilled in the art are conceivable, but they are to be understood as meaning, in particular, a coefficient of adhesion and/or a moisture level and/or particularly advantageously a grass height and/or grass density. As a result, specific properties of the surface to be processed can be advantageously taken into account. 
     It is conceivable here, in particular, that the computing unit is provided for setting a large overlap in the case of high and dense grass as opposed to low and sparse grass. As a result, overloading of the mower motor can be advantageously avoided. 
     It is also proposed that the computing unit have at least one sensor which is provided for sensing at least one parameter. A “sensor” is to be understood in this context as meaning, in particular, a unit which is provided for registering at least one characteristic variable and/or one physical property, wherein the registration can be active, such as can occur, in particular, as a result of the generation and emission of an electrical measurement signal, and/or passive such as can occur, in particular, as a result of detection of changes in properties of a sensor component. As a result, an underlying surface parameter can be taken into account actively and, in particular, dynamically in a reliable and completely autonomous fashion. 
     In addition it is proposed that the computing unit have at least one input unit which is provided for registering manual inputs of parameters by an operator. An “input unit” is to be understood in this context as meaning, in particular, a unit which has at least one operator control element and preferably at least one output element such as, in particular, a display. The input element is preferably connected directly to the computing unit. Alternatively or additionally, the input unit and/or at least one second input unit could be arranged separately from the computing unit and, in particular, separately from the part of the autonomous working device which, in order to perform work, is moved in a driven fashion over the surface to be processed. The input unit could be arranged, for example, in a remote control means and/or in a fixed station of the autonomous working device. Transmission of information to the computing unit could occur here via a cableless radio link and/or via an interface. In this context, a “fixed station” is to be understood as meaning, in particular, a station of the autonomous working device which is provided for registering the part of the autonomous working device during a rest phase. The station is preferably provided for filling an energy accumulator of the part of the autonomous working device. Filling can occur, for example, by means of refueling, changing an energy carrier and/or charging an accumulator; however, other methods which appear appropriate to a person skilled in the art are also conceivable. The station is particularly preferably arranged in an edge region of the surface to be processed and serves as a starting point and/or end point for the part of the autonomous working device. As a result, parameters can be input easily and comfortably by an operator. 
     The configuration permits the autonomous working device to be advantageously set to the requirement of an operator. As a result, in particular user-specific prescriptions can be registered. 
     It is also proposed that the computing unit be provided for taking into account a desired result, which has been input into the input unit, during the setting of the overlap. In this context, a “desired result” is to be understood as meaning, in particular, a result which is desired by an operator such as, for example, a specific time prescription and/or a specific level of quality and/or gentle treatment of the lawn. As a result, by means of simple input by an operator it is advantageously possible to produce complex peripheral conditions. In addition, the prescriptions of the operator can consequently be taken into account without the operator inputting a plurality of parameters. 
     Furthermore, it is proposed that the computing unit be provided for taking into account an overlap parameter, which has been input into the input unit, for the surface to be processed and/or for various partial regions and/or conditions of the surface to be processed. If, for example, an overlap parameter which reduces an overlap is input by an operator by means of the input unit, a mowing time can be shortened, wear can be reduced and/or the lawn can be treated gently. On the other hand, if an overlap is made larger, complete processing of the surface to be processed can be ensured. An “overlap parameter” is to be understood in this context as meaning, in particular, a parameter which directly determines dimensioning of an overlap. “Conditions of the surface to be processed” is to be understood as meaning, in particular, particular peripheral conditions which change depending on position and/or orientation despite the position of the autonomous working device remaining the same. This can be understood as meaning, for example, conditions such as a sloping inclination in which it is possible to differentiate between being parallel to a slope and perpendicular to the slope. As a result, differentiating conditions of the surface to be processed can easily be input by an operator, as a result of which in turn sensors and other detection units can be dispensed with. 
     The computing unit can preferably also be provided for taking into account, during the setting of the overlap, a speed parameter which is selected by an operator. As a result, overloading of the drive motor can be advantageously avoided. 
     In addition it is proposed that the computing unit be provided for determining its own position within an outline map and calculating an intersection point of an expected strip direction with the outline map during the determination of an expected strip length before a strip is traveled along. In this context, an “expected strip length” is to be understood as meaning, in particular, a strip length which the autonomous working device travels along the surface to be processed without incidents which are unpredictable for it such as, for example, an unknown obstacle. An “outline map” is to be understood in this context as meaning, in particular, a virtual sensing line which is stored in the memory of the computing unit and which represents a boundary of the surface to be processed. Furthermore, an “expected strip direction” is to be understood as meaning, in particular, an expected direction of movement of the autonomous working device during a subsequent strip. As a result it is advantageously possible to calculate an expected strip length easily. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Further advantages can be found in the following description of the drawings. The drawings illustrate an exemplary embodiment of the disclosure. The drawings, the description and the claims contain numerous features in combination. A person skilled in the art will expediently also consider the features individually and combine them to form further appropriate combinations. 
       In the drawings: 
         FIG. 1  shows an autonomous working device according to the disclosure with a computing unit in a schematic illustration, 
         FIG. 2  shows the autonomous working device according to the disclosure on a surface to be processed, in a schematic illustration, and 
         FIG. 3  shows a partial detail of two schematically illustrated strips, which overlap one another, of the autonomous working device. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  shows an autonomous working device  10  according to the disclosure with a computing unit  12 . The autonomous working device  10  is formed by an autonomous lawnmower. The autonomous working device  10  has a computing unit  12  and is provided for traveling in strips  16 ,  18 ,  20 ,  22 ,  24 ,  26 ,  28 ,  30 ,  32  along a surface  14  to be processed ( FIG. 2 ). In addition, the autonomous working device  10  has a drive motor (not shown further). The surface  14  to be processed is formed by a lawn surface. The computing unit  12  is arranged inside a housing  46  of the autonomous working device  10 . The computing unit  12  has a computing core  48  and a memory element  50 . The computing core  48  serves to process information, and the memory element  50  serves to store information. The computing core  48  and the memory element  50  are connected via a line. In addition, the computing unit  12  is connected to a location unit  52  which is also located in the housing  46  of the autonomous working device  10  and is provided for determining the position of the autonomous working device  10 . The location unit  52  is connected to the computing core  48  of the computing unit  12  via a line. The computing unit  12  is provided for setting an overlap  34  of the strips  16 ,  18 ,  20 ,  22 ,  24 ,  26 ,  28 ,  30 ,  32  as a function of a plurality of parameters. The overlap  34  is set by a change in the lateral movement of the autonomous working device  10  between the strips  16 ,  18 ,  20 ,  22 ,  24 ,  26 ,  28 ,  30 ,  32 . 
     The overlap  34  is defined by a difference between a strip width  54  and a relative distance  56 ,  58  between two strips  16 ,  18 ,  20 ,  22 ,  24 ,  26 ,  28 ,  30 ,  32 . The relative distance  56 ,  58  between two strips  16 ,  18 ,  20 ,  22 ,  24 ,  26 ,  28 ,  30 ,  32  represents the distance  56 ,  58  between center lines  60 ,  62  of the strips  16 ,  18 ,  20 ,  22 ,  24 ,  26 ,  28 ,  30 ,  32 .  FIG. 3  represents here merely a partial detail of the two strips  16 ,  18 . The strips  16 ,  18  have an identical strip width  54  and are spaced apart relative to one another by the distance  56 , resulting in the overlap  34 . 
     In addition, the computing unit  12  is provided for setting the overlap  34  in a differentiated fashion for various partial regions  36 ,  38  and for various strips  16 ,  18 ,  20 ,  22 ,  24 ,  26 ,  28 ,  30 ,  32  of the surface  14  to be processed. In the case of a surface  14  to be processed as shown in  FIG. 2 , various overlaps  34  are set for two partial regions  36 ,  38 , as a result of which the relative distances  56 ,  58  between the strips  16 ,  18 ,  20 ,  22 ,  24 ,  26 ,  28 ,  30 ,  32  also change. The surface  14  to be processed has a narrow partial region and a wide partial region  38  when considered perpendicularly to the strips  16 ,  18 ,  20 ,  22 ,  24 ,  26 ,  28 ,  30 ,  32  of the autonomous working device  10 . A station  64  of the autonomous working device  10  is arranged at an end of the narrow partial region  36  facing away from the wide partial region  38 . 
     The computing unit  12  is provided for taking into account a strip length parameter. The computing unit  12  is provided for taking into account an expected strip length during the setting of the overlap  34 . The strip lengths in the wide partial region  38  are long compared to the strip lengths in the narrow partial region  36 . Accordingly, the strips  26 ,  28 ,  30 ,  32  in the wide partial region  38  have a large overlap compared to the overlaps  34  of the narrow partial region  36 . Accordingly, the strips  26 ,  28 ,  30 ,  32  of the wide partial region  38  have a small relative distance  58  between the strips  26 ,  28 ,  30 ,  32  compared to the strips  16 ,  18 ,  20 ,  22 ,  24  of the narrow partial region  36 . 
     The computing unit  12  is provided for setting the overlap  34  of one of the strips  16 ,  18 ,  20 ,  22 ,  24 ,  26 ,  28 ,  30 ,  32  as a function of a specific parameter of the corresponding strip  16 ,  18 ,  20 ,  22 ,  24 ,  26 ,  28 ,  30 ,  32 . The computing unit  12  is provided for setting the overlap  34  of one of the strips  16 ,  18 ,  20 ,  22 ,  24 ,  26 ,  28 ,  30 ,  32  as a function of an expected strip length of the corresponding strip  16 ,  18 ,  20 ,  22 ,  24 ,  26 ,  28 ,  30 ,  32 . 
     Furthermore, the computing unit  12  is provided for taking into account an underlying surface parameter. The computing unit  12  is provided for taking into account a current grass height and grass density during the setting of the overlap  34 . In the case of high and dense grass, an overlap  34  which is large compared to low and sparse grass is set in order to avoid overloading the drive motor (not shown further). 
     In addition, the computing unit  12  has a sensor  40  which is provided for sensing at least one parameter. The sensor  40  is provided for sensing a grass height and grass density. The sensor  40  is arranged in the housing  46  of the autonomous working device  10  and is connected via a line to the computing core  48  of the computing unit  12 . The sensor  40  is arranged in an area of the housing  46  at the front considered in a direction of travel  66 . The housing  46  has an opening (not shown further) by means of which the sensor  40  can sense a grass height and grass density. 
     The computing unit  12  has an input unit  42  which is provided for registering manual inputs of parameters by an operator. The input unit  42  is arranged on the housing  46  of the autonomous working device  10  and is connected to the computing core  48  of the computing unit  12  via a line. The input unit  42  has a keypad  68 , a display  70  and a rocker switch  72 . 
     The computing unit  12  is provided for taking into account a desired result, which has been input into the input unit  42 , during the setting of the overlap  34 . An operator can input a desired result into the input unit  42 . An input is made by means of the rocker switch  72  of the input unit  42 . The rocker switch  72  has a position a and a position b. If the rocker switch  72  is in a position a, a high quality level of the mowing result is desired by an operator. If the rocker switch  72  is in a position b, an energy saving mode is desired by an operator. The rocker switch  72  can only be in one of the two positions a, b. A position of the rocker switch  72  is included in the calculation for the setting of the overlap  34  by the computing unit  12 . 
     The computing unit  12  is provided for taking into account an overlap parameter, which has been input into the input unit  42 , for the surface  14  to be processed and for various partial regions  36 ,  38 , and conditions of the surface  14  to be processed. An overlap parameter can be input into the input unit  42  by means of the keypad  68 . The overlap parameter can be set either to the entire surface  14  to be processed or to a partial region  36 ,  38  in which the overlap parameter is to be applied. The overlap parameter is set for the corresponding partial region  36 ,  38  directly by the computing unit  12 . All further parameters sensed by the computing unit  12  or all further operator control parameters are not taken into account for this. 
     At the start of a mowing process, the presence of overlap parameters which have been input by an operator is checked by the computing unit  12 . If overlap parameters are present, the mowing process is carried out according to these prescriptions, and further parameters are not taken into account here. If there is no overlap parameter which has been input by an operator, a position a, b of the rocker switch  72  of the input unit  42  is checked by the computing unit  12 . Depending on the position a, b of the rocker switch  72 , a fixed overlap value is stored. In the position a, the overlap value is large compared to the position b. Subsequently, a grass height and grass density is sensed by means of the sensor  40 . A further overlap value is calculated on the basis of the sensed grass parameters by the computing unit  12 . The overlap values of the rocker switch  72  and of the sensed grass parameters are averaged to form an initial overlap. In a next step, the mowing process is started. Before one of the strips  16 ,  18 ,  20 ,  22 ,  24 ,  26 ,  28 ,  30 ,  32  is traveled along in each case, an expected strip length is calculated. The computing unit  12  is provided for determining its own position within an outline map  44  and calculating an intersection point of an expected strip direction with the outline map  44  during the determination of an expected strip length before one of the strips  16 ,  18 ,  20 ,  22 ,  24 ,  26 ,  28 ,  30 ,  32  is traveled along. A distance between the intersection point and the position yields an expected strip length. A strip length overlap is calculated on the basis of this strip length by means of the computing unit  12 , and is temporarily reconciled with the initial overlap. The resulting overlap  34  is set for this strip  16 ,  18 ,  20 ,  22 ,  24 ,  26 ,  28 ,  30 ,  32 . After the conclusion of the strip  16 ,  18 ,  20 ,  22 ,  24 ,  26 ,  28 ,  30 ,  32 , the resulting overlap  34  is reset and a new resulting overlap  34  is calculated and set for a new strip  16 ,  18 ,  20 ,  22 ,  24 ,  26 ,  28 ,  30 ,  32  by means of the strip length and the initial overlap.