Patent Publication Number: US-2022210968-A1

Title: Implement Carrier

Description:
TECHNICAL FIELD 
     The present disclosure relates to an implement carrier comprising an implement carrier body driven by a driving arrangement, the implement carrier being configured for connecting alternatingly with at least a first and a second implement, the imple-ment carrier further comprising at least one sensor module adapted for scanning at least a portion of the area surrounding the implement carrier and a connected implement. 
     BACKGROUND 
     Such implement carriers are useful for carrying out different tasks over a working surface. By changing the implement, a completely different task can be executed, for instance, at a driving range switching from picking up golf balls to mowing grass, or the like. A sensor module allows the implement carrier to operate more or less autonomously or to improve the functioning of the implement for instance by detecting obstacles or other objects. It also makes it possible to assess properties of the working surface, such as for instance estimating grass length to adjust a mowing implement. 
     One problem associated with implement carriers of this type is that different implements may have different requirements and may affect the operation of the sensor module in different ways. 
     SUMMARY 
     One object of the present disclosure is therefore to obtain a solution that is more adaptable depending on which task is carried out and with which implement. This object is achieved by means of an implement carrier as defined in claim  1 . More specifically, in an implement carrier of the initially mentioned kind, a moveable sensor module arm is provided, having a proximal end connected to the implement carrier body. The at least one sensor module is arranged on the sensor module arm at a distance from the proximal end. This means that the sensor module can be moved depending on which implement is used and other circumstances. The sensor module position can thereby be flexible with regard to used implement and other conditions. 
     Typically, the sensor arm may be movable between a first position adapted for the first implement and a second position adapted for the second implement. The implement carrier may then detect an implement type and adjust the arm accordingly, although this can also be made manually. 
     The sensor arm may also be configured to move depending on the relative position of the implement in relation to the implement carrier. For instance, the sensor arm can move based on the difference in elevation between the implement carrier and the implement. This makes it possible for instance to raise the robot arm somewhat when the implement reaches a steep upward slope thereby making sure that the sensor module continues to monitor the area in front of the implement rather than the implement itself. 
     The sensor arm may also be configured to move depending on the steering of the implement carrier. This makes it possible to monitor the area where the implement is going rather than just the area in front of the implement. 
     The sensor arm may be formed by at least two parts forming a parallelogram, such that moving of the arm alters a viewing direction of the sensor unit. In this way, it is made possible that the sensor module attains the correct inclination automatically when the arm is moved. 
     The sensor module may include sensors in the group: RADAR, ultrasound sensors, cameras, LIDAR, for instance. 
     The implement carrier may be driven by wheels or bands, and typically one implement may be a lawn mower. 
     The sensor module arm may comprise one or more pivotable joints in between the proximal end and the sensor module. This makes the arm even more flexible. 
     There may be provided connector on the sensor module arm for connecting with a socket on at least one connected implement. This makes it possible to affix the sensor module on the implement in some cases. 
     The sensor arm may be telescopic and may further be connected to the implement carrier in such a way that it is pivotable about an axis being substantially vertical. This allows the sensor arm to be more extendable and to look sideways and behind the implement carrier, for instance. 
     The sensor arm may be configured to move during transport of the implement carrier to avoid obstacles in the sensor arm path. 
     Further examples and variations are described in the following detailed description in connection with the following drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates one example where a sensor module is arranged on an implement carrier. 
         FIG. 2  illustrates an example where a sensor module is instead arranged on an implement. 
         FIG. 3  illustrates an implement carrier with a sensor module arranged on a sensor module arm according to the present disclosure. 
         FIG. 4A and 4B  illustrate a sensor module arm which mechanically adjusts a sensor module inclination depending on arm movements. 
         FIG. 5  illustrates a sensor module arm with multiple joints. 
         FIG. 6  illustrates a telescopic sensor module arm. 
         FIG. 7  illustrates a sensor module arm capable of turning sideways with regard to the travelling direction of the implement carrier. 
         FIG. 8  illustrates an implement carrier carrying out surveying during processing of a surface. 
         FIG. 9  illustrates elements of a control system for an implement carrier. 
         FIG. 10  illustrates an implement carrier moving, and the sensor arm adapting to circumstances as the implement carrier moves. 
     
    
    
     DETAILED DESCRIPTION 
     The present disclosure relates to an implement carrier, such as in the form of a self-propelled robotic tool. An implement carrier is shown in  FIG. 1 . 
     The implement carrier  1  comprises an implement carrier body  3  which is driven by a driving arrangement such as wheels  5  or bands. The implement carrier  1  itself need not provide a processing function, although this is certainly possible. Instead, the implement carrier is designed to connect alternatingly with different implements  7  in order to provide a more diverse use. For instance, the implement carrier may be connected to a lawn mower implement to cut lawns in the summer, and to a snow thrower in the winter. Several other implements are possible, such as golf ball collectors, leaf blowers, brushes, etc. The implements are typically at least partly self-supporting, i.e. are at least not entirely suspended from the implement carrier. 
     Implement carriers of this kind have so far mainly been in the form of manually driven garden tractors, but the recent successful introduction of self-propelled robotic tools such as robotic lawnmowers implies the possibility to combine the two concepts. 
     A self-propelled tool can navigate using sophisticated navigation means such as GPS navigation and even real time kinematics, RTK, but most robotic lawnmowers at present typically navigate randomly within an area defined by a buried limitation cable that is detected by the lawnmower. 
     In order to provide an improved operation of the self-propelled tool, at least one sensor module  11  is provided that scans the area surrounding the implement carrier  1  and a connected implement  7 ,  9 , or at least a portion of this area. 
     This sensor module  11  may contain one or several sensors that provide sensor data to the self-propelled robotic tool&#39;s control system. The sensor module  11  may typically include an ultrasound sensor that is capable of detecting obstacles and other objects in the vicinity of the self-propelled robotic tool in order to, for instance, avoid that the robotic tool bumps into and potentially damages nearby objects. Ultrasound sensors, RADAR and LIDAR , for instance, are other suitable solutions for providing this function. Cameras may also be used, and the control system may be configured to detect and optionally classify different objects in the self-propelled robotic tool&#39;s vicinity. 
     This may be used for instance to determine that if object in the vicinity can readily be moved by the robotic tool, e.g. a plastic toy, or not, e.g. a rock. 
     A camera may also be used to optimize the implement&#39;s working characteristics depending on circumstances in the environment. For instance, a camera may acquire images of a lawn to be cut that is used for example to determine a suitable cutting height. 
       FIG. 1  illustrates one way of arranging such a sensor module  11 . In this case, the sensor module is associated with the implement carrier  1 , e.g. as illustrated is mounted on the top of its body  3  in a position overlooking the area in front of the attached implement  7 , in this case a grass mowing tool. While this may work fine together with this implement  7 , replacing that implement with another, such as a brushing tool as shown in  FIG. 2 , would render the sensor module  11  less useful, as that implement  9  would obscure the view of the sensor module  11  in such a way that no meaningful scanning of the area in front of the implement  9  can take place. 
     In  FIG. 2 , there is instead schematically illustrated another option, where the sensor module  11  is instead located on the implement  9 . This of course makes it possible to optimize a sensor module  11  placement with regard to the implement  9  used. However, this comes at the cost of providing a sensor module  11  for each implement used, as well as the cost for providing a sensor module interface between the implement and the implement carrier in order to allow the sensor module  11  to communicated with a control unit of the implement carrier  1 . 
     The present disclosure includes a sensor module  11  that is arranged on a sensor module arm  13  in order to provide a more versatile arrangement as illustrated with an example in  FIG. 3 . Very briefly, this arrangement comprises a moveable sensor module arm  13  on which the sensor module  11  is arranged. The arm has a proximal end  15  which is connected to the implement carrier body  3 . The sensor module  11  is arranged on the sensor module arm at its distal end  17  or at least a distance from the proximal end  15 , which may have a joint  16  where the arm can be moved. Thereby, the location of the sensor module  11  can be altered by moving the sensor module arm  13 . This means that a single sensor module  11  can be located at different positions depending for instance on which implement  7 ,  9  is used. The joint  16  can be located elsewhere on the sensor module arm  13 . 
     The sensor arm may thus be movable between a first position adapted for the first implement  7  and a second position adapted for the second implement  9 . It is possible to configure the implement carrier such that it detects the type of implement and adjusts the sensor arm position accordingly. 
     It may further be desired to move the sensor arm depending on the relative position of the implement carrier  1  and the implement  7 . For instance, if the implement  7  is a lawn mower implement, it is suitable to let the sensor module detect objects immediately in front of the implement in order e.g. to avoid that sharp knives of the implement  7  damages object left on the lawn, etc. However, if the implement carrier approaches an uphill section, the implement will become raised in a way that the sensor module instead records the top of the implement  7 . Therefore, it may be preferred to raise the elevation of the sensor module arm  13  in response to the implement being raised by the uphill section. This may be accomplished by providing an angular sensor in the interface in between the implement carrier and the implement. It is also possible to make the sensor module are  13  operate based on data from the sensor module  11  that indicates that the sensor need be moved. 
     It is possible to make the sensor module  11  direction automatically respond to movements of the sensor module arm  13 . This may be accomplished with electronic means in the sensor module  11  that detects movements of the sensor module arm  13  by means e.g. of accelerometers and adjusts the viewing direction of the sensor module  11  accordingly. However, it would also be possible to provide such a function with simple mechanical means.  FIG. 4A and 4B  illustrate a sensor module arm  13  which mechanically adjusts a sensor module  11  inclination depending on sensor module arm movements. The arm includes at least two bars  19  that are pivotably connected, somewhat spaced apart, to both the implement carrier body  3  and the sensor module  11 . The bars  19  thereby form a parallelogram, where a moving of the arm  13  as a whole automatically alters a viewing direction of the sensor unit  11 . In this way, the sensor module can thus be made to view e.g. an area right in front of the implement regardless of the elevation of the sensor module arm  13 . 
     The sensor module arm can be provided with functions similar to a commercial robotic arm.  FIG. 5  illustrates a sensor module arm  13  with an additional joint  21  that allows the sensor module  11  to be positioned with an even greater freedom of movement. The sensor module arm  13  may thus comprise one or more pivotable joints in between the proximal end  15  and the sensor module  11 . 
     It is further possible, as illustrated in  FIG. 6 , to provide a telescopic function  23  on the sensor module arm  13  that allows it to be lengthened or shortened. It may be suitable to provide navigation equipment such as an RTK unit  25  in connection with the sensor module  11  as this part can be position at an increased height with regard to the remainder of the implement carrier which provides an improved reach to a base station or the like. 
     As illustrated in  FIG. 7 , it is possible to make the sensor arm  13  pivot sideways by providing a swiveling function, typically with bearings  27  or the like. Thereby, the sensor arm  11  becomes pivotable about an axis which is substantially vertical or at least has a significant vertical component. This gives a greater freedom of movement that allows the sensor module to register data at various other location not neces-sarily located directly in front of the implement. 
     For instance, as illustrated in  FIG. 8  an implement carrier carries out surveying during processing of a surface. Then, instead of just monitoring the surface  29 , directly in front of the implement  7 , the sensor unit may at least intermittently monitor other areas  31  that, for instance, the implement  1  and the implement carrier  7  are to process at a later stage. This information may be used for instance to update map information that is used to plan processing of a working surface, or to identify the implement carrier&#39;s position based on object nearby, etc. 
     It is also possible to turn the sensor arm  180  degrees from the normally used direction and monitor the area behind the implement carrier  1 , thereby allowing the implement carrier to reverse with improved safety. 
       FIG. 9  shows elements of a control system for an implement carrier that illustrate the flexible uses of the combination of the sensor unit  11  and the sensor module arm  13  in the implement carrier  1 . 
     The system generally includes the sensor module  11 , the sensor module arm  13 , a control unit  33 , and optionally a map-and navigation unit  35 . The later two could conceivably be included in a remote device to which communication is provided with a radio interface or the like. 
     Some functions have already been mentioned such as the sensor module  11  providing data to the control unit  33  to improve steering or processing of a working area, and providing information to the map and navigation unit  35  for mapping an area or obtaining positioning data. In addition to those functions, the sensor arm  13  could be configured to move depending on the steering of the implement carrier  1 , such that the sensor unit  11  monitors an area to which the implement carrier  1  is about to steer towards rather than just the area straight in front of the implement  7 . The sensor module  11  may also be capable of controlling the sensor arm  13  during transport of the implement carrier  1 , for instance to avoid obstacles in the sensor arm path. 
       FIG. 10  illustrates an implement carrier  1  moving, and the sensor arm  13  adapting to circumstances to this movement. Compared to when moving on a flat surface as shown to the left, the sensor arm  13  is being elongated when an uphill section raises the implement, as previously discussed. An alternative, as mentioned, is to raise the sensor arm. The right section of  FIG. 10  illustrates a case where the implement reaches an obstacle  41 . In this case, the sensor arm is elongated even further to look on the other side of the obstacle  41 . It would also be possible to provide the sensor arm  13  with a tool at it distal end to make it possible to remove a light obstacle, for instance a claw. 
     That illustrated position of the sensor arm could also be useful to look into the fron of the implement, for example to determine whether an object has become stuck therein or if the implement is damaged for some other reason. 
     It would be possible to temporarily connect the sensor module arm  13  to the implement that provides a fixed position for the sensor module  11 , if desired. Then, there may be provided a connector  43  on the sensor module arm for connecting with a socket  45  on a connected implement, cf  FIG. 3 . 
     The present invention is not limited to the above described examples, and can be altered and varied in different ways within the scope of the appended claims.