Patent Publication Number: US-2021163130-A1

Title: Mounting mechanism, landing gear, frame, and unmanned aerial vehicle

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a continuation of International Application No. PCT/CN2018/079054, filed on Mar. 14, 2018, the entire content of which is incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates to the field of unmanned aerial vehicle (UAV) and, more specifically, to a mounting mechanism, a landing gear, a frame, and a UAV. 
     BACKGROUND 
     The landing gear is an attachment that supports the UAV and enables various maneuvers of the UAV. It has an important role during the safe takeoffs and landings of the UAV, and is one or the important components of the UAV. 
     UAVs have been widely used in aerial photography, forest conservation projects, surveying and mapping, and other fields. In order to prevent the landing gear from bumping against fixed objects on the ground (such as trees, houses, etc.) during the flight of the UAV, the landing gear is generally designed to be retractable. 
     However, this type of retractable landing gear can be captured in the acquired images of the camera during the rotation of the gimbal. Therefore, some manufacturers fix the landing gear on the gimbal, such that when the gimbal rotates, the landing gear can be synchronously rotated to prevent the landing gear from being captured in the acquired images. However, fixedly connecting the landing gear to the gimbal can affect the stability of the gimbal, resulting in decreased imaging quality. 
     SUMMARY 
     One aspect of the present disclosure provides a mounting mechanism of a UAV. The mounting mechanism includes a rotating part rotatably connected with a center frame of the UAV and connected with a landing gear disposed under the center frame; and a driving part driving the rotating part to rotate when a carrier disposed under the center frame for carrying a payload rotates. 
     Another aspect of the present disclosure provides a landing gear of a UAV. The landing gear is disposed under a center frame of the UAV, and includes a carrier disposed under the center frame for carrying a payload; and a mounting mechanism including a rotating part rotatably connected with the center frame and connected with the landing gear, and a driving part driving the rotating part to rotate when the carrier rotates. 
     Another aspect of the present disclosure provides a UAV. The UAV includes a landing gear disposed under a center frame of the UAV; a gimbal disposed under the center frame of the UAV for carrying a payload; and a mounting mechanism including a rotating part rotatably connected with the center frame and connected with the landing gear, and a driving part driving the rotating part to rotate when the carrier rotates. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In order to illustrate the technical solutions in accordance with the embodiments of the present disclosure more clearly, the accompanying drawings to be used for describing the embodiments are introduced briefly in the following. It is apparent that the accompanying drawings in the following description are only some embodiments of the present disclosure. Persons of ordinary skill in the art can obtain other accompanying drawings in accordance with the accompanying drawings without any creative efforts. 
         FIG. 1  is a structural diagram of a UAV according to an embodiment of the present disclosure. 
         FIG. 2  is a diagram of a mounting mechanism according to an embodiment of the present disclosure. 
         FIG. 3  is a structural diagram of the mounting mechanism according to another embodiment of the present disclosure. 
         FIG. 4  is an exploded view of a driving part according to an embodiment of the present disclosure. 
         FIG. 5  is a structural diagram of another mounting mechanism according to an embodiment of the present disclosure. 
         FIG. 6  is a structural diagram of yet another mounting mechanism according to an embodiment of the present disclosure, in which a landing gear is mounted on the mounting mechanism. 
         FIG. 7  is a structural diagram of the mounting mechanism in  FIG. 6  from another perspective. 
         FIG. 8  is an exploded view of  FIG. 6 , in which the lower half of the landing gear is cut off. 
         FIG. 9  is an exploded view of a support part and a rotating part in  FIG. 8 . 
     
    
    
     REFERENCE NUMERALS 
     
         
           1  UAV 
           10  Center frame 
           30  Power assembly 
           50  Landing gear 
           60  Connector 
           70  Mounting mechanism 
           71  Rotating part 
           711  Driven gear 
           712  Rotating shaft 
           713   a  Upper cover 
           713   b  Lower cover 
           73  Driving part 
           731  Motor 
           731   a  Output shaft 
           732  Transmission gear 
           733  Transmission belt 
           734  Motor mounting base 
           735  Bearing support base 
           736  Second bearing 
           737  Motor protection cover 
           738  LED module 
           75  Support part 
           751  Supporting block 
           753  First bearing 
           7551   a  Upper support 
           7551   b  Lower support 
           7552  Ball 
           7553   a  Upper rail 
           7553   b  Lower rail 
           77  Dust cap 
           771  Mounting hole 
           773  Positioning protrusion 
           79  Dust cover 
           90  Gimbal 
           2  Imaging device 
       
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Technical solutions of the present disclosure will be described in detail with reference to the drawings. It will be appreciated that the described embodiments represent some, rather than all, of the embodiments of the present disclosure. Other embodiments conceived or derived by those having ordinary skills in the art based on the described embodiments without inventive efforts should fall within the scope of the present disclosure. 
     In the present disclosure, when terms such as “center,” “longitudinal,” “lateral,” “length,” “width,” “thickness,” “above,” “upper,” “below,” “lower,” “back,” “left,” “right,” “vertical,” “horizontal,” “top,” “bottom,” “inside,” “outside,” “internal,” “external,” “clockwise,” “counter-clockwise” are used to indicate orientational or positional relationship that is based on the orientation or positional relationship as shown in the drawings, it is for the convenience of describing various embodiments and for the simplification of the descriptions. Such terms do not indicate or imply a related device or element necessarily has the specified orientation, or is structurally configured in the specified orientation or is operated in the specified orientation. Thus, these terms are for illustrative purposes only and are not intended to limit the scope of the present disclosure. 
     It should be understood that in the present disclosure, relational terms such as first and second, etc., are only used to distinguish an entity or operation from another entity or operation, and do not necessarily imply that there is an actual relationship or order between the entities or operations. Therefore, a “first” or “second” feature may include, explicitly or implicitly, one or more such features. The term “multiple” means two or more than two, unless otherwise defined. 
     In the present disclosure, unless specified or limited otherwise, the terms “mounted,” “connected,” “coupled,” “fixed” and the like are used broadly, and may be, for example, fixed connections, detachable connections, or integral connections; may also be mechanical or electrical connections; may also be direct connections or indirect connections via intervening structures; may also be inner communications of two elements or interactions of two elements, which can be understood by those skilled in the art according to specific situations. 
     Reference throughout this specification to “an embodiment,” “some embodiments,” “an example,” “a specific example,” or “some examples,” means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present disclosure. In this specification, exemplary descriptions of aforesaid terms are not necessarily referring to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples. Moreover, those skilled in the art could combine different embodiments or different characteristics in embodiments or examples described in the present disclosure. In addition, when there is no conflict, those skilled in the art may combine different embodiments, or examples and features of different embodiments, or examples described in the present disclosure. 
       FIG. 1  is a structural diagram of a UAV according to an embodiment of the present disclosure. As shown in  FIG. 1 , a UAV  1  includes a center frame  10 , which is the main part of the UAV  1 . The center frame  10  generally includes a flight control system of the UAV  1  to control the flight status of the UAV  1 , such as controlling the ascent, landing, steering, and hovering of the UAV  1 . In some embodiments, the flight control system may be a microprocessor, a microcontroller, or an integrated circuit. The center frame  10  includes a top surface, a bottom surface and a plurality of side surfaces positioned between the top surface and the bottom surface. The space enclosed by the top surface, bottom surface, and the side surfaces may be used to mount the flight control system described above and a battery for powering the UAV  1 , etc. Of course, in some embodiments, a mounting cavity for mounting the battery may also be formed by recessing the bottom surface of the center frame  10 , and a battery cover may be detachably disposed at an opening of the mounting cavity. 
     A plurality of arms are generally evenly disposed around the center frame, and these arms may be symmetrical about the horizontal axis or the vertical axis of the center frame  10 . For example, as shown in  FIG. 1 , four arms are disposed symmetrically about the horizontal axis and the vertical axis around the center frame  10 . The arms may be fixedly connected to the center frame  10 , and may also be rotationally connected to the center frame  10 . Alternatively, the arms may be design to be folded relative to the center frame  10  to reduce the space occupied by the UA  1  when stored. For example, one end of the arm close to the center frame  10  may be inserted from the side of the center frame  10  between the top surface and the bottom surface of the center frame  10  to improve the connection strength between the arm and the center frame  10 . It should be understood that although one end of the arm can be inserted into the center frame  10  from the side of the center frame  10  as described above, this arrangement may not affect the fixed connection or the rotational connection between the arm and the center frame center frame  10 . The arm can be made into any suitable shape using any materials in conventional technology. For example, the arm can be made into a rod-shaped structure using metal (such as iron or aluminum) or non-metal (such as polymer plastic). Of course, in order to reduce the weight and improve the power performance of the UAV  1 , the arm can be made of carbon fiber material into a hollow rod-like structure or a plate-like structure with weight-reducing holes (as shown in  FIG. 1 ). 
     One or more power assemblies  30  can be mounted at the end of the arm away from the center frame  10  to provide power for the ascent, forward, hover, and rotation of the UAV  1 . The power assembly  30  may include a propeller, a drive motor that drives the propeller to rotate, and an electronic speed control (ESC) that controls the operating parameters of the drive motor. It should be understood that when a plurality of power assemblies  30  are provided on the same arm of the UAV  1 , these power assemblies  30  may be disposed on the arm at intervals along the extending direction of the arm, or two power assemblies  30  may also be disposed symmetrically at the end of the arm as shown in  FIG. 1 . 
     A carrier for carrying a payload may be mounted below the center frame  10 , such that the UAV  1  can implement certain auxiliary function through the payload being carried. In some embodiments, the payload may be fixed to the bottom surface of the center frame  10  directly or through an adapter. In the present embodiment, the carrier may be a gimbal  90  that allows the payload to rotate about one or more rotation shafts  712  or provide stability to the payload or to control the state of the payload to rotate, translate, etc. The gimbal  90  in the present embodiment may include, but is not limited to, a single-axis gimbal, a dual-axis gimbal, and a three-axis gimbal. Of course, the carrier may also be other structures for carrying objects, such as a hanging basket or a mechanical claw. 
     In the present embodiment, the payload can refer to a payload or any part of the object supported by the gimbal  90 . The payload can be configured to not perform any operation or function. Alternatively, the payload may be configured to perform a corresponding operation or function, which can be referred to as a functional payload. For example, the payload may include one or more sensors for surveying one or more targets. The sensor can collect information about the environment around the sensor. Any suitable sensor may be incorporated into the payload, such as an imaging device  2  (such as a visual imaging device including an image acquisition device and a camera, an ultraviolet imaging device, a thermal imaging device, etc.), an audio capturing device (such as a parabolic microphone), a radio frequency (RF) sensor, a magnetic sensor, an ultrasonic sensor, etc. In some embodiments, the payload may include a single type of sensor, emitter, and/or tool, or multiple types of sensors emitters, and/or tools. In addition, the payload may also include any number of sensors, emitters, and/or tools and combinations thereof, such as a sensor array. 
     In the following embodiments, an example will be described in which the carrier is a three-axis gimbal and the payload is an imaging device  2 . In some embodiments, the three-axis gimbal may be a gimbal that can rotate around a first axis (e.g., a yaw axis), a second axis (e.g., a roll axis), and a third axis (e.g., a pitch axis). When the three-axis gimbal rotates around the yaw axis, the imaging device  2  supported by the three-axis gimbal may also rotate synchronously about the yaw axis. 
     A plurality of landing gears  50  may also be disposed below the center frame  10  to support the UAV  1  when the UAV  1  lands on the ground or other ground fixed objects, thereby preventing the main structures, such as the center frame  10  of the UAV  1  from contacting the ground or ground fixed objects to protect the UAV  1 . Generally, the landing gear  50  may be made of carbon fiber material into a hollow rod-like structure to reduce the weight and improve the power performance of the UAV  1 . Of course, the embodiments of the present disclosure do not exclude the use of other lightweight, high-strength, or other material to make the landing gear  50 . 
     Although the carbon fiber material is used to make the landing gear  50 , when the landing gear  50  is fixed on the gimbal  90  to prevent the landing gear  50  from entering the imaging range (hereinafter referred to as the image) of the imaging device  2  carried by the gimbal  90 , some manufacturers have fixed the landing gear  50  on the gimbal  90 . As such, when the gimbal  90  rotates, the landing gear  50  can also rotate synchronously to ensure that the landing gear  50  does not appear in the image of the imaging device  2 . However, the gimbal  90  of this UAV  1  needs to rotate the landing gear  50  at the same time as it drives the imaging device carried by the gimbal  90 . Although the quality of the landing gear  50  has been reduced through the selection of materials, the landing gear  50  will still affect the modalities of the gimbal  90  itself, resulting in reduced stability of the gimbal  90 , which in turn affects the imaging quality of the imaging device  2 . For example, the image of the imaging device  2  may become blurry, and the stability of the gimbal  90  itself may be reduced, which can cause safety concerns of the imaging device  2  carried by the gimbal  90 . 
     In view of the above, an embodiment of the present disclosure further provides a mounting mechanism  70  disposed below the center frame  10  for mounting the landing gear  50  described above. A part of the mounting mechanism  70  (hereinafter referred to as a rotating part  71 ) may be rotatably connected to the center frame  10 . That is, the rotating part  71  can rotate relative to the center frame  10 , and the landing gear  50  may be fixed to the rotating part  71 . As such, the rotating part  71  may rotate relative to the center frame  10  to adjust the position of each landing gear  50  relative to the center frame  10 , thereby preventing the landing gear  50  from appearing in the image of the imaging device  2  when the gimbal  90  drives the imaging device to rotate. In addition, since the landing gear  50  is fixed to the rotating part  71  of the mounting mechanism  70 , the gimbal  90  does not need to drive the landing gear  50  rotate when it rotates, which can improve the stability of the gimbal  90  and the imaging quality of the imaging device  2 . 
     More specifically, in some embodiments, the rotating part  71  of the mounting mechanism  70  and the gimbal  90  may be both connected to the flight control system. The flight control system can send control signals to the mounting mechanism  70  and the gimbal  90  to control the rotation of the yaw axis of the rotating part  71  and the gimbal  90 . For example, control the rotation of the yaw axis of the rotating part  71  and the gimbal  90  to rotate synchronously. That is, the rotation direction and rotation speed of the yaw axis of the rotating part  71  and the gimbal  90  may be the same, such that the landing gear  50  may also rotate synchronously when the gimbal  90  rotates, thereby preventing the landing gear  50  from entering the image of the imaging device  2  carried by the gimbal  90 . Of course, the flight control system can also control the yaw axis of the rotating part  71  and the gimbal  90  to rotate at different angles, as long as the landing gear  50  does not enter the image of the imaging device  2  during the rotation of the gimbal  90 . It should be understood that when other payloads are carried by the gimbal  90 , such as other sensors, the yaw axis of the rotating part  71  and the gimbal  90  can be controlled to rotate synchronously or by different angles through the flight control system, such that the landing gear  50  may not interfere with other payloads, such as not blocking the sensing area of a RF sensor, etc. In addition, although the above description is directed to the flight control system controlling the rotation of the rotating part  71  and the gimbal  90 , in some embodiments, the rotation of the rotating part  71  and the gimbal  90  may also be controlled by a remote controller or a ground station wireless connected to the UAV  1 . Of course, the remote controller may directly control the rotating part  71  and the gimbal  90 , or indirectly through the flight control system. 
       FIG. 2  is a diagram of a mounting mechanism according to an embodiment of the present disclosure. As shown in  FIG. 2 , in order to drive the rotating part  71  to rotate relative to the center frame  10  to adjust the relative position of the landing gear  50  fixed to the rotating part  71  and the center frame  10 , such that the landing gear  50  may not enter the image of the imaging device  2  carried by the gimbal  90 , the mounting mechanism  70  may further include a driving part  73 . The driving part  73  may be used to drive the rotating part  71  to rotate when the gimbal  90  rotates. It should be understood that the driving part  73  may be used only to drive the rotating part  71  to rotate, or may be used to simultaneously drive the rotating part  71  and the gimbal  90  to rotate. In addition, in order to support the driving part  73  and realize the rotatable connection of the rotating part  71  and the center frame  10 , a support part  75  may be disposed on the rotating part  71  to fixedly connect to the center frame  10 . More specifically, the support part  75  ad the bottom surface of the  10  may be fixed by bolts, screws, rivets, or the like. The rotating part  71  may be connected to the support part  75  and may rotate relative to the support part  75 . 
     Several mounting mechanisms  70  will be described below, but those skilled in the art should understand that these mounting mechanisms  70  are exemplary and not specific limitations of the present disclosure. If a person skilled in the art replaces or combines one or more components in the following mounting mechanisms  70 , or replaces or combines one or more technical features, etc., it should be considered as within the protection scope of the claims of the present disclosure. 
       FIG. 3  is a structural diagram of the mounting mechanism according to another embodiment of the present disclosure, and  FIG. 4  is an exploded view of a driving part  73  according to an embodiment of the present disclosure. As shown in  FIGS. 3 and 4 , in the present embodiment, the rotating part  71  includes a rotating shaft  712  and a driven member drivenly connected to the driving part  73 , and the driven member includes, but is not limited to, a driven wheel or a driven gear  711 . The bottom of the rotating shaft  712  is fixed to the driven member, and the top of the rotating shaft  712  is rotatably connected to the support part  75 . The driving part  73  may include a motor  731  and a transmission component. The motor  731  may be connected to the driven member through the transmission component, such that the motor  731  can drive the driven member to rotate to adjust the position of the landing gear  50  fixed on the rotating shaft  712 . 
     Still referring to  FIGS. 3 and 4 , the transmission component may include a first transmission member mounted on the output shaft of the motor, and a second transmission member for drivingly connecting the first transmission member and the driven member. For example, the first transmission member may be a transmission wheel or a transmission gear  722 , the second transmission member may be a transmission belt  733 , a transmission chain, or a transmission gear, and the driven member may be a driven wheel or the driven gear  711 . Taking the first transmission member as the transmission gear  732 , the second transmission member as the transmission belt  733 , and the driven member as the driven gear  711  as an example, the transmission gear  732  may be mounted on an output shaft  731   a  of the motor  731 , the driven gear  711  ma be fixed to the bottom of the rotating shaft  712 , and the transmission belt  733  may be sleeved on the outside of the transmission gear  732  and the driven gear  711  to transmit the torque of the motor  731  to the rotating shaft  712 . It should be understood that the inner surface of the transmission belt  733  may be provided with teeth matching the transmission gear  732  and the driven gear  711  to avoid slippage of the transmission belt  733  and improve the transmission stability. 
     In the present embodiment, the motor  731  may be directly fixed on the center frame  10 , or the driving part  73  may further include a support base fixedly connected to the center frame  10  (as shown in  FIG. 4 ). The motor  731  may be mounted on the support base. For example, in some embodiments, the support base may include a motor mounting base  734  and a bearing support base  735 . In particular, support base of the motor  731  may be fixedly connected to the center frame  10  (e.g., support base of the motor  731  may be fixed to the side of the center frame  10 ). The motor  731  may be mounted on the motor mounting base  734 , the bearing support base  735  may be mounted below the support base of the motor  731 . A second bearing  736  may be mounted on the bearing support base  735 , and the output shaft  731   a  of the motor  731  may pass through the second bearing  736  and be fixed to the transmission member (e.g., to the transmission gear  732  described above). Based on the above description, by providing the bearing support base  735  and the second bearing  736 , the rigidity of the transmission gear  732  can be improved and the deformation of the transmission gear  732  can be reduced, thereby avoiding slippage of the transmission belt  733  during transmission and improving the reliability of the belt transmission. 
     In some embodiments, as shown in  FIG. 4 , in order to protect the motor  731  of the driving part  73 , the driving part  73  further includes a motor protection cover  737 , which is disposed on the outside of the motor  731 . In some embodiments, the motor protection cover  737  may include an LED module  738  for indicating the flight control state and/or power state of the UAV, and alarm when the flight control state and/or power state of the UAV is abnormal. For example, when the LED module  738  of the driving part  73  is turned on, the LED module  738  disposed on the motor protection cover  737  may display the flight control state and/or power state of the UAV to the user by lighting, changing colors, and blinking. Of course, if the flight control state and/or power state of the UAV is abnormal, the user can also be alerted by the color or the flashing time of the LED module  738 . 
     In some embodiments, the driving part  73  may be disposed at the rear of the UAV, such that the user may observe the LED module  738 . At the same time, an interface may be disposed on the LED module  738 , which can be used to connect the parameter adjustment cable of the flight control parameters of the UAV. 
     In the present embodiment, the support part  75  may be directly fixed on the bottom surface of the center frame  10  or formed as an integral piece with the bottom surface of the center frame  10  by integral molding. More specifically, the support part  75  may be a supporting block  751  or other structures described below, such as a first bearing  753 . Taking the supporting block  751  as an example, it may form a matching structure with the top of the rotating shaft  712 , such that the rotating shaft  712  may rotate relative to the supporting block  751 . 
     For example, the fitting structure described above may be a screw connection structure as shown in  FIG. 3 . That is, the top of the rotating shaft  712  is screwed to the supporting block  751 . More specifically, a mounting hole is formed on the supporting block  751 , an internal thread is formed on the inner wall of the mounting hole, and an external thread matching the internal thread is formed on the top of the rotating shaft  712 . As such, when the transmission belt  733  drives the driven gear  711  to rotate, the top of the rotating shaft  712  fixed connected to the driven gear  711  can also rotate in the mounting hole through the screw fitting structure described above. 
     Further, the fitting structure described above may include one or more teeth formed on the top of the rotating shaft  712 , and one or more teeth formed on the supporting block  751  that mesh with the one or more teeth formed on the top of the rotating shaft  712 . More specifically, an upper gear may be mounted at the top of the rotating shaft  712 , and a mounting hole may be formed in the supporting block  751 . A plurality of teeth formed in a closed ring shape and meshing with the teeth on the upper gear at the top of the rotating shaft  712  may be formed on the inner wall of the mounting hole. 
       FIG. 5  is a structural diagram of another mounting mechanism according to an embodiment of the present disclosure. As shown in  FIG. 5 , in the present embodiment, the support part  75  is the first bearing  753  fixed to the bottom surface of the center frame  10 , and at least a part of the rotating part  71  in stalled in the first bearing  753 . As such, the rotating part  71  may rotate around the axis of the first bearing  753  to rotate the landing gear  50  fixedly connected to the rotating part  71 , thereby preventing the landing gear  50  from entering the image of the imaging device  2 . 
     In some embodiments, the first bearing  753  may be a ball bearing fixed on the bottom surface of the  10 . The rotating part  71  may include a club and a driven member, the head of the club may be accommodated in a ball socket of the ball bearing, such that the club may rotate relative to the ball bearing. The other end of the club may be fixed to the driven member, and the club may be further used to fix the landing gear  50 . In the present embodiment, the driven member fixed to the other end of the club may be a driven wheel or the driven gear  711 , such that when the driving part  73  drives the driven member to rotate (e.g., when the transmission belt  733  drives the driven gear  711  as the driven member to rotate), the head of the club fixed to the driven member may rotate in the ball socket of the ball bearing. As such, the landing gear  50  fixed on the club may follow the club to avoid entering the image of the imaging device  2  carried by the gimbal  90 . Of course, the other end of the rotating part  71  may not be provided with a driven member, and the transmission connection with the driving part  73  may be realized in other ways. In the present embodiment, the driving part  73  may be the driving part  73  described in the above embodiment, which will not be repeated here. For details, reference may be made to the content of the above embodiment. 
     In other embodiments, the first bearing  753  may be a sliding bearing or a rolling bearing fixed on the bottom surface of the center frame  10 . In the present embodiment, the sliding bearing or the rolling bearing may be a sliding bearing or a rolling bearing generally used in conventional technology. For example, a ball bearing or a roller bearing may be used. Of course, this embodiment does not exclude the use of other structures having the same principle as the sliding bearing or rolling bearing of this embodiment, such as a rolling bearing with improved structure, which will be described below. During installation, the sliding bearing or rolling bearing may be fixed to the bottom surface of the center frame  10  through a bearing housing, or a mounting hole can be formed on the bottom surface of the center frame  10 , and then the sliding bearing or rolling bearing may be installed in the mounting hole. 
     In the present embodiment, the rotating part  71  may include the rotating shaft  712  whose top may be mounted in a sliding bearing or a rolling bearing, and a driven member fixed to the bottom surface of the rotating shaft  712  and drivingly connected to the driving part  73 , the driven member may be a driven wheel or the driven gear  711 . Of course, this embodiment also does not exclude the use of other structures having the same principle as the rotating shaft  712  and he driven member as the rotating part  71  of this embodiment, such as an improved rotating part  71 , which will be described below. It should be noted that the driving part  73  may be the driving part  73  described in the above embodiment, which will not be repeated here. For details, reference may be made to the content of the above embodiment. 
     The following takes the flight control system controlling the driving part  73  to drive the rotating part  71  to rotate as an example to briefly describe the working processing of the mounting mechanism  70  to drive the landing gear  50  to rotate. In particular, the driving part  73  may include the motor  731 , the transmission gear  732 , and the transmission belt  733 ; the rotating part  71  may include the driven gear  711  and the rotating shaft  712 ; and the support part  75  may be a rolling bearing. 
     The flight control system may send a control signal to the motor  731  of the driving part  73  based on information such as the rotation speed and rotation direction that the yaw axis of the gimbal  90  needs to rotate. The motor  731  may rotate based on the control signal, thereby driving the transmission gear  732  to rotate. Subsequently, the transmission belt  733  sleeved on the transmission gear  732  and the driven gear  711  fixed at the bottom of the rotating shaft  712  may transmit the torque of the transmission gear  732  to the driven gear  711 , such that the driven gear  711  may drive the rotating shaft  712  fixed on the driven gear  711  to rotate in the rolling bearing, thereby driving the landing gear  50  fixedly connected to the rotating shaft  712  to rotate. As such, the landing gear  50  may be located outside the image of the imaging device  2  carried by the gimbal  90 . 
     In some embodiments, the rotating shaft  712  described above can be designed as a hollow shaft, such that the adapter connected to the gimbal  90  can pass through the hollow shaft and be fixed to the bottom surface of the center frame  10 . By designing the rotating shaft  712  as a hollow shaft in order to pass the adapter of the gimbal  90  through the hollow shaft, on one hand, can protect a connector  60  of the gimbal  90 , and on the other hand, can reduce the wind resistance of the UAV  1  in flight. From a visual point of view, reducing the number of exposed parts can further enhance the aesthetics of the UAV  1 . Based on the above, by designing the rotating part  71  as a hollow structure along the axial direction, the adapter for connecting the carrier may pass through the hollow structure, which can not only protect the adapter, but also reduce the wind resistance and improve the appearance of the UAV  1 . 
       FIG. 6  is a structural diagram of yet another mounting mechanism according to an embodiment of the present disclosure, in which the landing gear  50  is mounted on the mounting mechanism.  FIG. 7  is a structural diagram of the mounting mechanism in  FIG. 6  from another perspective.  FIG. 8  is an exploded view of  FIG. 6 , in which the lower half of the landing gear is cut off. As shown in  FIGS. 6-8 , the mounting mechanism  70  includes a driving part  73 , a support part  75 , a rotating part  71 , a dust cap  77 , and a dust cover  79 , where the driving part  73  is the same as the structure of the above embodiment. For details, reference may be made to the above description, which will not be repeated here. The support part  75  includes an upper support  7551   a , a lower support  7551   b , an upper slide rail  7553   a , a lower side rail  7553   b , and a ball  7552 . The rotating part  71  includes an upper cover  713   a , a driven gear  711 , and a lower cover  713   b.    
     For the convenience of description, the parts other than the driving part  73  in  FIG. 8  will be described separately in order from top to bottom. 
       FIG. 9  is an exploded view of a support part and a rotating part in  FIG. 8 . Referring to  FIGS. 8 and 9 , in the present embodiment, the upper support  7551   a  is disposed at the uppermost end and forms a fixed connection with the bottom surface of the center frame  10 . The upper slide rail  7553   a  is disposed under the upper support  7551   a , and the ball  7552  is disposed between the upper support  7551   a  and the upper slide rail  7553   a , such that the upper slide rail  7553   a  can rotate relative to the upper support  7551   a . The upper cover  713   a  is disposed under the upper slide rail  7553   a , and the lower slide rail  7553   b  is disposed under the upper cover  713   a . That is, the upper cover  713   a  is clamped between the upper slide rail  7553   a  and the lower slide rail  7553   b . The lower support  7551   b  is disposed under the lower side rail  7553   b , and the lower support  7551   b  and the upper support  7551   a  are fixedly connected by bolts, screws, or rivets. The ball  7552  is disposed between the lower slide rail  7553   b  and the lower support  7551   b , such that the lower slide rail  7553   bj  can rotate relative to the lower support  7551   b.  In addition, since the upper cover  713   a  is sandwiched between the upper slide rail  7553   a  and the lower side rail  7553   b , the upper slide rail  7553   a , the upper cover  713   a , and the lower slide rail  7553   b  can rotate relative to the upper support  7551   a  and the lower support  7551   b  as a whole. 
     In other words, in the present embodiment, the upper support  7551   a  and the lower support  7551   b  can be considered as an outer ring of the rolling first bearing  753  as a whole, and the upper slide rail  7553   a  and the lower side rail  7553   b  can be considered as an inner ring of the rolling first bearing  753  as a whole. That is, in some variations, the rolling first bearing  753  may include a support for fixing with the center frame  10  and a slide rail for holding the contact position of the rotating part  71 . The ball  7552  may be disposed between the slide rail and the support, such that the rotating part  71  tightly connected to the slide rail can rotate relative to the support. 
     The slide rail can be of any shape. For example, both the upper slide rail  7553   a  and the lower slide rail  7553   b  may be selected as round slide rails, curved slide rails, or hollow circular slide rails. 
     Still referring to  FIGS. 8 and 9 . In some embodiments, there may be a plurality of upper supports  7551   a , and the plurality of upper supports  7551   a  may be evenly arranged on the outer edge of the upper slide rail  7553   a  to increase the supporting force to make the upper slide rail  7553   a  more stable. Similarly, there may be a plurality of lower supports  7551   b , and the plurality of lower supports  7551   b  may be evenly arranged on the lower slide rail  7553   b . For example,  FIGS. 8 and 9  illustrate a specific example of four upper supports  7551   a  evenly disposed along the outer edge of the upper slide rail  7553   a , and four lower supports  7551   b  evenly disposed along the outer edge of the lower slide rail  7553   b . Of course, this embodiment also does not exclude making the upper supports  7551   a  and the lower supports  7551   b  into a ring shape. 
     Further, a plurality of balls  7552  may be disposed between the upper supports  7551   a  and the upper slide rail  7553   a . For example, two balls  7552  may be disposed between the upper supports  7551   a  and the upper slide rail  7553   a . That is, when there are a plurality of upper supports  7551   a , two balls  7552  may be disposed between each upper support  7551   a  and the upper slide rail  7553   a . For example,  FIGS. 8 and 9  illustrate four upper supports  7551   a  and two balls  7552  being disposed between each upper support  7551   a  and the upper slide rail  7553   a . By disposing a plurality of balls  7552  between the upper support  7551   a  and the upper slide rail  7553   a , the rotational resistance of the upper slide rail  7553   a  can be reduced. Similarly, a plurality of balls  7552  may be disposed between the lower supports  7551   b  and the lower slide rail  7553   b . For example,  FIGS. 8 and 9  illustrate four lower supports  7551   b  and two balls  7552  being disposed between each upper support  7551   b  and the lower slide rail  7553   b.    
     Still referring to  FIGS. 8 and 9 . The dust cap  77  may be disposed on the outside of the upper slide rail  7553   a  and the lower slide rail  7553   b , such that the upper slide rail  7553   a  and the lower slide rail  7553   b  may be accommodated in the dust cap  77  to prevent dusting from falling onto the upper slide rail  7553   a  and the lower slide rail  7553   b  and affecting the rotation of the upper slide rail  7553   a  and the lower slide rail  7553   b.    
     Further, in order to cooperate with the upper support  7551   a  and the lower support  7551   b , a mounting hole  771  may be disposed at the top of the dust cap  77 , and parts of the upper support  7551   a  and the lower support  7551   b  used to cooperate with the balls  7552  may extend into the dust cap  77  through the mounting hole  771 . It should be understood that to prevent the dust cap  77  from falling, the dust cap  77  can be directed fixed on the bottom surface of the center frame  10  by bolts, screws, or other fasteners. Alternatively, the dust cap  77  and the lower support  7551   b  may be fixedly connected. In addition, parts of the upper support  7551   a  and the lower support  7551   b  are located outside the dust cap  77  in this embodiment, in other embodiments, the upper support  7551   a  and the lower support  7551   b  may be completely accommodated in the dust cap  77 . At this time, the dust cap  77  may be fixed to the bottom surface of the center frame  10  by bolts, screw, or other fasteners. Further, a plurality of positioning protrusions  773  may be formed in the dust cap  77 , and the lower support  7551   b  can be disposed at intervals with the positioning protrusions to reduce the shear force on the screw when the lower support  7551   b  is connected to the dust cap  77 . Furthermore, a positioning groove matching the positioning protrusions may be formed on the lower surface of the upper cover  713   a.    
     Still referring to  FIGS. 8 and 9 . The driven gear  711  that is in driving connection with the driving part  73  may be disposed below the upper cover  713   a . Of course, the driven gear  711  may be replace with a driven wheel as the driven member that is driving connected to the driving part  73 . In addition, if the dust cap  77  is disposed outside the slide rail, the driven wheel should be disposed under the dust cap  77  to facilitate the transmission connection with the driving part  73 . 
     The lower cover  713   b  for attaching the landing gear  50  may be disposed below the driven gear  711 , and the dust cover  79  as shown in  FIGS. 8 and 9  may be selectively sandwiched between the lower cover  713   b  and the driven gear  711 . The upper cover  713   a , the driven gear  711 , and the lower cover  713   b  may be fixedly connected by fixing pins, bolts, rivets, etc., such that when the transmission belt  733  of the driving part  73  drives the driven gear  711  to rotate, the upper cover  713   a  and the lower cover  713   b  fixedly connected to the driven gear  711  may also rotate correspondingly. More specifically, the upper cover  713   a  may rotate with the upper slide rail  7553   a  and the lower slide rail  7553   b  relative to the upper support  7551   a  and the lower support  7551   b , respectively. Of course, in the present embodiment, the driven gear  711  may be replaced by a driven wheel or other components. 
     It should be understood that the upper cover  713   a  and the lower cover  713   b  of the rotating part  71 , and the dust cover  79  sandwiched between the lower cover  713   b  and the driven gear  711  are not necessarily required structures. For example, in some variations, the rotating part  71  may not include the lower cover  713   b . At this time, the landing gear  50  may be fixed on the upper cover  713   a  or the driven gear  711  (such as the lower surface of the driven gear  711 ). That is, in the present embodiment, the rotating part  71  may include an end cover and a driven member, where the end cover may include only the upper cover  713   a , or both the upper cover  713   a  and the lower cover  713   b ; and the driven member may be a driven wheel or the driven gear  711 . More specifically, the end cover may be sandwiched between the upper slide rail  7553   a  and the lower slide rail  7553   b , or rotatably connected to the upper slide rail  7553   a  and/or the lower slide rail  7553   b ; the driven member may be fixed to the end cover; and the landing gear  50  may be fixed to the end cover. 
     Further, in some variations, the rotating part  71  may not include the upper cover  713   a . At this time, the landing gear  50  may be fixed to the driven gear  711  or an intermediate piece connected to the driven gear  711 , and the driven gear  711  may be fixed to the upper slide rail  7553   a  and/or the lower slide rail  7553   b , such that the driven gear  711  may rotate relative to the upper slide rail  7553   a  and/or the lower slide rail  7553   b.    
     Still referring to  FIG. 8 , an attachment part may be formed on the lower cover  713   b , and the landing gear  50  may be attached to the attachment part via a connector  60 . 
     It should be noted that the upper slide rail  7553   a , the lower slide rail  7553   b , the upper cover  713   a , the lower cover  713   b , and the driven gear  711  may be made into a hollow structure. That is, the slide rails, end covers, and the driven member may be made into a hollow structure for the adapter of the gimbal  90  to pass through. With this arrangement, on one hand, the UAV  1  may include an adapter, and on the other hand, the wind resistance of the UAV  1  in flight may be reduced. From a visual point of view, reducing the number of exposed parts can further enhance the aesthetics of the UAV  1 . 
     In addition, an embodiment of the present disclosure further provides a UAV landing gear, which includes the mounting mechanism  70  and the landing gear  50  described above. Further, an embodiment of the present disclosure also provides a UAV frame, which includes the landing gear  50  and the center frame  10  described above. That is, the UAV of this embodiment may include the frame and the gimbal disposed under the frame described above. 
     Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the embodiments disclosed herein. It is intended that the specification and examples be considered as exemplary only and not to limit the scope of the disclosure, with a true scope and spirit of the invention being indicated by the following claims.