Patent Publication Number: US-2016236346-A1

Title: Multi-link type working apparatus moved by thrust generating device

Description:
RELATED APPLICATION 
     This application claims the benefit of Korean Patent Application No. 10-2015-0024404, filed on Feb. 17, 2015, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference. 
     BACKGROUND 
     1. Field 
     One or more exemplary embodiments relate to a multi-link type working apparatus, and more particularly, to a multi-link type working apparatus moved by a thrust generating device, wherein the multi-link type working apparatus performs a work by moving a link apparatus, in which a plurality of links are connected by at least one joint, by using the thrust generating device. 
     2. Description of the Related Art 
     A multi-link type working apparatus having a structure in which a plurality of links are connected by at least one joint is used in various fields. The multi-link type working apparatus has a simple structure but is capable of performing a complex work, such as nonlinear movement or force transmission. 
     A general multi-link type working apparatus includes a link apparatus in which a plurality of links are connected by at least one joint, and an actuator driving the link apparatus. One end of the link apparatus is fixed, and an end effector for various works is provided at another end of the link apparatus. Each of the links forming a link assembly is moved by the actuator, such as a motor or a hydraulic cylinder. 
     Types of a multi-link type working apparatus may vary and may include an industrial robot, a manipulator, and a crane. For example, KR 0292013 (published on Feb. 19, 2002) discloses a crane in which a hydraulic cylinder moves connected links to transfer garbage to an incinerator. Also, KR 1229025 (published on Feb. 01, 2013) discloses a multi-joint manipulator that is able to collect an accident vehicle or a disable vehicle by including a pivot joint or a prism joint. KR 2013-0042247 (published on Apr. 26, 2013) discloses a manipulator in which a pair of auxiliary links are connected to a main rotary link via a pair of brackets to be used for a palletizing operation in an industrial site. 
     A general multi-link type working apparatus has a restriction on the length or number of links due to a limitation of an actuator operating a link, and has a low degree of freedom of a mid-air operation. When the number of links is high or the length of each link is long, torque of the general multi-link type working apparatus, which is required to operate the links, may geometrically increase. 
     SUMMARY 
     One or more exemplary embodiments include a multi-link type working apparatus moved by a thrust generating device, in which lengths of links, the number of links, and the freedom of movement may be varied by using the thrust generating device as an actuator for moving the links. 
     Additional aspects will be set forth in part in the description which follows and, in part, will be apparent from the description, or may be learned by practice of the presented embodiments. 
     According to one or more exemplary embodiments, a multi-link type working apparatus moved by a thrust generating device, includes a link apparatus that comprises a plurality of links and at least one joint connecting two neighboring links between each of the plurality of links; a plurality of thrust generating device that comprise a control module enabling communication between an external device and a rotor generating thrust to control operations of the rotor, and are respectively combined to the plurality of links of the link apparatus to move the plurality of links; and a control device that comprises a controller in which a control process for controlling the plurality of thrust generating device is stored, and a communicator transmitting a control signal to the plurality of thrust generating device according to the control process. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and/or other aspects will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings in which: 
         FIG. 1  is a diagram of a multi-link type working apparatus moved by a thrust generating device, according to an exemplary embodiment; 
         FIG. 2  is an exploded diagram of some components of the multi-link type working apparatus of  FIG. 1 , according to an exemplary embodiment; 
         FIG. 3  is a diagram for describing a peg-in-hole operation performed by the multi-link type working apparatus of  FIG. 1 ; 
         FIG. 4  is a diagram of a multi-link type working apparatus moved by a thrust generating device, according to another exemplary embodiment; 
         FIG. 5  is an exploded diagram of some components of a multi-link type working apparatus moved by a thrust generating device, according to another exemplary embodiment; and 
         FIG. 6  is a diagram of a multi-link type working apparatus moved by a plurality of thrust generating devices, according to another exemplary embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     A multi-link type working apparatus moved by a thrust generating device, according to one or more exemplary embodiments, will now be described with reference to accompanying drawings, wherein like reference numerals refer to like elements throughout. 
       FIG. 1  is a diagram of a multi-link type working apparatus  100  moved by a thrust generating device  140 , according to an exemplary embodiment, and  FIG. 2  is an exploded diagram of some components of the multi-link type working apparatus  100  of  FIG. 1 , according to an exemplary embodiment. 
     As shown in  FIGS. 1 and 2 , the multi-link type working apparatus  100  includes a link apparatus  110 , a plurality of the thrust generating devices  140 , and a control device  160 . The multi-link type working apparatus  100  may perform various works by moving the link  110  by using the plurality of thrust generating devices  140 . 
     The link apparatus  110  includes a plurality of links  111  and a plurality of joints  118 . A combining groove  112  for combining of the joint  118  may be provided at each of two ends of the link  111 . A plurality of insertion grooves  113  and a connection module  114  for connecting of the thrust generating device  140  are provided at the middle of the link  111 . The connection module  114  is for electric connection with the thrust generating device  140 . An electric wire  115  connected to the connection module  114  is provided inside the link  111 . 
     The plurality of joints  118  connect the two neighboring links  111  between each of the plurality of links  111 . According to the current embodiment, the joint  118  has a ball joint structure in which a first connecting member  119  includes a ball and a second connecting member  120  includes a socket into which the ball is inserted. A first combining protrusion  121  is provided at an end of the first connecting member  119 , and a second combining protrusion  122  is provided at an end of the second connecting member  120 . The first combining protrusion  121  of the first connecting member  119  is inserted into the combining groove  112  of any one of the links  111 , and the second combining protrusion  122  of the second connecting member  120  is inserted into the combining groove  112  of the other one of the links  111 . The first and second combining protrusions  121  and  122  respectively include terminals  123  and  124  for electric connection. The terminal  123  of the first combining protrusion  121  and the second terminal  124  of the second combining protrusion  122  may be mutually electrically connected to each other. At this time, an electric wire (not shown) for electrically connecting the terminals  123  and  124  may be provided inside the joint  118 . The terminals  123  and  124  may be connected to each other via a cable provided outside the joint  118 . 
     The first and second combining protrusions  121  and  122  of the joint  118  are respectively combined to the two neighboring links  111 , and thus the joint  118  connects the two neighboring links  111  such that joint movement is possible, and at the same time, electrically connects the two neighboring links  111 . Accordingly, the plurality of thrust generating devices  140  connected to the connection module  114  of each of the plurality of links  111  may be mutually electrically connected to each other through the plurality of links  111  and the plurality of joints  118 . 
     An end effector  130  is provided at an end of the link apparatus  110 . According to the current embodiment, the end effector  130  has a gripper structure having a function of gripping an object. The end effector  130  has a combining protrusion  131  that is inserted into the combining groove  112  of the link  111 . The end effector  130  is detachably combined to the link  111  through the combining protrusion  131 . The combining protrusion  131  of the end effector  130  includes a terminal  132  for electric connection. A driver  133  of the end effector  130  may receive power and a control signal through the terminal  132 . When the combining protrusion  131  of the end effector  130  is inserted into the combining groove  112  of the link  111 , the terminal  132  of the end effector  130  is electrically connected to the electric wire  115  of the link  111 . Accordingly, the end effector  130  may receive power and the control signal through the link  111 , and may be electrically connected to the thrust generating device  140  combined to the link  111 , through the link  111 . In  FIG. 1 , a pair of the end effectors  130  are provided respectively at two ends of the link apparatus  110 , but alternatively, the end effector  130  may be provided only at one end of the link apparatus  110 . 
     As shown in  FIG. 1 , the plurality of thrust generating devices  140  are respectively combined to the plurality of links  111  of the link apparatus  110  to move the plurality of links  111 . According to the current embodiment, the thrust generating device  140  is a multi-rotor type unmanned aerial vehicle (UAV) having a plurality of rotors  143 . As widely known, a multi-rotor type UAV has a simple structure and is capable of vertical takeoff and landing, prompt flight, and hover flight. 
     Referring to  FIG. 2 , the thrust generating device  140  includes a support frame  141 , the plurality of rotors  143  provided at the support frame  141 , and a control module  146  controlling operations of the plurality of rotors  143 . The support frame  141  includes four mounts that radially extend from a center of the support frame  141 . The control module  146  is provided at the center of the support frame  141 , and the rotor  143  is provided at each of the four mounts  142 . The rotor  143  includes a wing  144  and a motor  145  to generate thrust. Operations of the rotor  143  are controlled by the control module  146 . 
     As shown in  FIG. 1 , the control module  146  generates a rotating direction and a rotating speed of each of the plurality of rotors  143 . The control module  146  includes a processor  147 , a position detector  148  such as an inertial measurement unit (IMU), and a communication module  149 . The control module  146  detects a flight state of the thrust generating device  140  and controls operations of the rotor  143 , thereby controlling flight of the thrust generating device  140 . Also, the control module  146  may be in wireless communication with the control device  160  on the ground through the communication module  149 . The control module  146  may receive a control signal from the control device  160  via communication with the control device  160  to control operations of the thrust generating device  140 , and transmit information about a state of the thrust generating device  140  to the control device  160 . 
     The thrust generating device  140  is detachably combined to the link  111  through a link connecting apparatus  150 . The link connecting apparatus  150  includes a pair of insertion protrusions  151  inserted into the insertion groove  113  of the link  111 , and a joint  152  combined to the support frame  141  of the thrust generating device  140 . According to the current embodiment, the joint  152  has a ball joint structure. When the thrust generating device  140  is combined to the link  111  through the link connecting apparatus  150  having the joint  152 , an angle of the thrust generating device  140  with respect to the link  111  may be variously adjusted. Accordingly, the link  111  may stably and smoothly move as the thrust generating device  140  tilts in any angle with respect to the link  111 . A structure of the joint  152  may not only be the ball joint structure, but may also be any other structure in which the thrust generating device  140  is combined to the link  111  such that the angle of the thrust generating device  140  is adjustable. The link connecting apparatus  150  may not include a joint. 
     The link connecting apparatus  150  mechanically combines, and at the same time, electrically connects, the link  111  and the thrust generating device  140 . Accordingly, an electric wire (not shown) for electric connection is provided inside the joint  152 . The insertion protrusion  151  of the link connecting apparatus  150  is electrically connected to the connection module  114  of the link  111  when inserted into the insertion groove  113  of the link  111 . Accordingly, the plurality of thrust generating devices  140  combined to the link apparatus  110  may be mutually electrically connected to the plurality of links  111  through the plurality of joints  118 , and may also be electrically connected to the pair of end effectors  130  combined to the link apparatus  110 . 
     As such, when the plurality of thrust generating devices  140  and the pair of end effectors  130  are all electrically connected, the control module  146  provided in any one of the plurality of thrust generating devices  140  may be used as a main controller controlling the plurality of thrust generating apparatuses  140  and the pair of end effectors  130 . In other words, the control module  146  provided in any one of the plurality of thrust generating devices  140  combined to the link apparatus  110  may receive a control signal from the control device  160 , and integrally operate the plurality of thrust generating devices  140  and the end effectors  130  such that a work using the end effectors  130  is smoothly performed. 
     When the thrust generating device  140  is combined to the link  111  of the link apparatus  100  through the link connecting apparatus  150 , the thrust generating device  140  may transmit information about its location on the link apparatus  110  to the control device  160 . When all of the thrust generating devices  140  transmits the information about their locations on the link apparatus  110  to the control device  160 , the control device  160  may control operations of each of the thrust generating devices  140  such that the plurality of links  111  integrally move for a work. The information about the locations may be provided via any one of various methods. For example, a location code may be set per connection module  114  of the link  111 , and when the insertion protrusion  151  of the link connecting apparatus  150  is connected to the connection module  114 , the location code of the connection module  114  may be transmitted to the thrust generating device  140  connected to the link connecting apparatus  150 . 
     The control device  160  includes a controller  161 , a communicator  162 , a manipulator  163 , and a display  164 . The communicator  162  is in communication with the thrust generating device  140 , and the display  164  may display various types of information about the multi-link type working apparatus  100 , such as an operating state of the multi-link type working apparatus  100 . The controller  161  stores a control process for controlling the end effector  130  and the thrust generating device  140 . The controller  161  transmits a control signal for operating the end effector  130  and the plurality of thrust generating devices  140  according to the stored control process to the thrust generating device  140  through the communicator  162 . At this time, the control module  146  of the thrust generating device  140 , which operates as a main controller, may control operations of the thrust generating devices  140  and the end effector  130  according to the control signal. 
     The manipulator  163  is used for a user input. A user may input a manipulation signal regarding the thrust generating device  140  or the end effector  130 , select a pre-set work mode, or change a work setting, through the manipulator  163 . 
       FIG. 3  is a diagram for describing a peg-in-hole operation performed by the multi-link type working apparatus  100  of  FIG. 1 . As shown in  FIG. 3 , the multi-link type working apparatus  100  according to the current embodiment may perform a work of inserting a peg  10  into a hole  30  formed on a wall  20  by moving the links  111  of the link apparatus  110  by using the plurality of thrust generating device  140  while the end effector  130  combined to the link apparatus  110  holds the peg  10 . The multi-link type working apparatus  100  may easily perform the peg-in-hole operation that is difficult and dangerous to be performed by a person since the plurality of thrust generating device  140  lift the link apparatus  110  to any height in mid-air. 
     In addition, the multi-link type working apparatus  100  according to an exemplary embodiment may perform various unmanned works as various end effectors having various working functions are replaced and combined at the link apparatus  110 . The multi-link type working apparatus  100  according to an exemplary embodiment may variously change the degree of freedom of the link apparatus by changing the number or structures of the links  111 , constraint conditions of the links  111 , and a structure of the joint  118 . A structure or the number of the thrust generating device  140  may also be changed. 
       FIG. 4  is a diagram of a multi-link type working apparatus  200  moved by a thrust generating device  240 , according to another exemplary embodiment. The multi-link type working apparatus  200  of  FIG. 4  includes a link apparatus  210 , the plurality of thrust generating devices  24 , and a control device  260 . 
     The link apparatus  210  includes a plurality of links  211  and a plurality of joints  218 . The joint has a ball joint structure, and connects the links  211  to each other. An end effector  230  is detachably combined to the link  211  at one end of the link apparatus  210 . According to the current embodiment, the end effector  230  has a gripper structure. The link  211  at the other end of the link apparatus  210  is connected to a base  222  through a joint  220 . The joint  220  has a ball joint structure. The base  222  supports the link apparatus  210 . The link apparatus  210  is constrained from moving by the joint  220 , and may tilt in any angle with respect to the base  222 . 
     A power supply apparatus  224  for supplying power is provided at the base  222 . An electric wire (not shown) is provided inside the link apparatus  210 , and power of the power supply apparatus  224  may be provided to the end effector  230  through the link apparatus  210  or to the plurality of thrust generating device  240  combined to the link apparatus  210 . A control signal of the control device  260  may be transmitted to the end effector  230  or the plurality of thrust generating devices  240  through the electric wire inside the link apparatus  210 . 
     The plurality of thrust generating device  240  are respectively combined to the plurality of links  211  of the link apparatus  210  to move the plurality of links  211 . The thrust generating device  240  includes a support frame  241 , a plurality of rotors  243  provided at the support frame  241 , and a control module  246  controlling operations of the plurality of rotors  243 . The support frame  241  is combined to a fixture  242  fixed to the link  211 . An electric wire (not shown) is provided inside the support frame  241  and the fixture  242  to transmit power and a control signal to the plurality of thrust generating devices  240 . Operations of the rotor  243  are controlled by the control module  246 . 
     The control module  246  is combined to the link  211 . The control module  246  controls a rotating direction and a rotating speed of each of the plurality of rotors  243 . The control module  246  includes a processor  247 , a position detector  248  such as an IMU, and a communication module  249 . The control module  246  receives power and a control signal through the link apparatus  210 , detects a flight state of the thrust generating device  240 , and controls operations of the rotor  243 . 
     The control device  260  includes a controller  261 , a communicator  262 , a manipulator  263 , and a display  264 . The structure of the control device  260  is similar to that described above. The communicator  262  is electrically connected to the link apparatus  210  through a cable  265  to be connected to the end effector  230  and the plurality of thrust generating devices  240  via wires. The controller  261  transmits a control signal for operating the end effector  230  and the plurality of thrust generating devices  240  according to the stored control process to the end effector  230  and the plurality of thrust generating devices  240  through the communicator  262 . 
     The multi-link type working apparatus  200  according to the current embodiment uses constraint conditions in which one end of the link apparatus  210  is connected to the base  222 . Accordingly, operation instability caused by under-actuation may be reduced and stable operation may be performed. By replacing the end effector  230  to another end effector having various functions, various works as well as grabbing an object may be performed. Also, since power may be continuously supplied to the end effector  230  or the plurality of thrust generating devices  240  from the ground, a work may be performed for hours. 
     According to the current embodiment, the thrust generating device  240  may be detachably combined to the link apparatus  210  as described in the previous embodiment. An electric wire may not be provided inside the link apparatus  210 , but a separate cable may be disposed outside the link apparatus  210 , thereby transmitting power and a control signal to the end effector  230  and the plurality of thrust generating devices  240  through the separate cable. 
     An end effector or a thrust generating device may not be mutually electrically connected to each other through a link apparatus, but may operate by individually receiving a control signal from a control device. For example,  FIG. 5  illustrates an end effector  330  and the thrust generating device  140  being simply mechanically combined to a link apparatus  310 . 
     According to the current embodiment, a plurality of links  311  of the link apparatus  310  is only mechanically connected to each other by a joint  318 . The end effector  330  is detachably combined to the link apparatus  310  as a combining protrusion  331  of the end effector  330  is inserted into a combining hole  312  of the link  311 . The thrust generating device  140  is detachably combined to the link  311  by a link connecting apparatus  350 . The link connecting apparatus  350  includes an insertion protrusion  351  that is inserted into an insertion groove  313  provided in the link  311 . According to the current embodiment, the end effector  330  may include a communicator (not shown) as well as a driver  333 , and operate upon receiving a control signal from a control device via wireless communication. 
       FIG. 6  is a diagram of a multi-link type working apparatus  400  moved by a plurality of thrust generating devices  440 ,  440 ′, and  440 ″, according to another exemplary embodiment. The multi-link type working apparatus  400  of  FIG. 6  includes a link apparatus  410 , the plurality of thrust generating devices  440  through  440 ″, a moving apparatus  460 , and the control device  160 . Here, the control device  160  has been described above with reference to  FIG. 1 . 
     The link apparatus  410  includes a plurality of links  411  and a plurality of joints  418 . An end effector  430  is detachably combined to the link  411  at one end of the link apparatus  410 . According to the current embodiment, the end effector  430  has a gripper structure. The link  411  at the other end of the link apparatus  410  is connected to the moving apparatus  460  through a joint  420 . The link apparatus  410  may be constrained from moving as the link apparatus  410  is combined to the moving apparatus  460  via the joint  420 , and may tilt in any angle with respect to the moving apparatus  460 . 
     The moving apparatus  460  may move on the ground by including a body  461 , a moving mechanism  462  including a plurality of wheels  463 , and a control unit  464 . The body  461  may include a power supply apparatus (not shown) to supply power to the moving mechanism  462 . The power supply apparatus may also supply power to the end effector  430  through an electric wire (not shown) inside the link apparatus  410  or to the thrust generating devices  440  through  440 ″ combined to the link apparatus  410 . The control unit  464  has a wireless communication function to receive a control signal from the control device  160 , and may control the moving mechanism  462 , the end effector  430 , or the plurality of thrust generating devices  440  through  440 ″ according to the received control signal. The end effector  430  or the plurality of thrust generating devices  440  through  440 ″ may each operate upon wirelessly receiving a control signal from the control device  160 . 
     Each of the plurality of thrust generating devices  440  through  440 ″ includes a pair of rotors  443 . The plurality of thrust generating devices  440  through  440 ″ are provided per link  441  of the link apparatus  410  to move the link  441 . In  FIG. 6 , different types of the thrust generating devices  440  through  440 ″ are provided for the link  441 , but the structures or number of thrust generating devices combined to the link  411  may vary. 
     In the multi-link type working apparatus  400  according to the current embodiment, since the link apparatus  410  is combined to the moving apparatus  460 , it is easy to move the link apparatus  410  to a work site, and thus the work site may be easily changed. The moving apparatus  460  may have an unmanned ground vehicle (UGV) structure, or may alternatively have any structure having a moving function. 
     As described above, the multi-link type working apparatuses  100 ,  200 , and  400  according to one or more exemplary embodiments use the thrust generating devices  140 ,  240 ,  440 ,  440 ′, and  440 ″ as actuators for moving the links  111 ,  211 , and  411 . Accordingly, thrust compensate for self-weights of the links  111 ,  211 , and  411 , and thus the lengths or numbers of the links  111 ,  211 , and  411  may vary and the degree of freedom of the link apparatuses  110 ,  210 , and  410  may easily expand. 
     One or more exemplary embodiments are described above, but the range of embodiments is not limited thereto. 
     For example, a thrust generating device may have any structure, for example, may include a single rotor, as well as a multi-rotor type UAV described above. 
     Also, an end effector may be a replacement type or a fixed type and may be a gripper, a driver, a spanner, a nail gun, or a camera. As occasion demands, an end effector may not be used, and at this time, various works may be performed by moving a link apparatus by using a plurality of thrust generating devices. 
     A multi-link type working apparatus moved by a thrust generating device, according to an exemplary embodiment, may variously expand lengths of links, the number of links, and the freedom of movement by using the thrust generating device as an actuator for moving the links, compared to a general multi-link type working apparatus that uses a motor or a hydraulic cylinder as an actuator. 
     Also, the multi-link type working apparatus may perform various mid-air works by lifting a link apparatus mid-air by using the plurality of thrust generating devices. Accordingly, the multi-link type working apparatus may be used in various fields, such as fields of structure evaluation and maintenance operations of suspension bridges or power line towers, fields of reconnaissance activities, firefighting fields, and entertainment fields of performances or parades using giant dolls. 
     While one or more exemplary embodiments have been described with reference to the figures, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the inventive concept as defined by the following claims.