Abstract:
A robot arm end effector mechanism for a mobile, remotely controlled robot includes an arm housing; an end effector bearing sleeve rotatable relative to the arm housing; a roll motor unit, fixed to the arm housing and having a roll drive axis, for rotating said bearing sleeve; and an end effector motor unit having an end effector drive axis and being fixed to and rotatable with the bearing sleeve for operating the end effector.

Description:
FIELD OF THE INVENTION 
       [0001]    This invention relates to a mobile, remotely controlled robot and more particularly to such a mobile, remotely controlled robot with an improved, in-line robot arm and end effector mechanism. 
       BACKGROUND OF THE INVENTION 
       [0002]    Mobile, remotely controlled robots are becoming increasingly popular for use by the military, SWAT units, and police and fire departments. The applicants&#39; TALON® robot, for example, includes an arm with an end effecter, several cameras, several antennas, and a deployable mast. Frequently the end effector is a gripper, e.g. a pair of jaws that can be opened and closed on command to grasp objects such as debris, hazardous material, unexploded ordinance and the like. The larger robots even have the capability to grip an injured, downed, person by some personal paraphernalia such as a shirt collar and drag them out of harm&#39;s way to safety. Presently, the upper arm of the robot has an end effector mounted on its distal end eccentric to its axis so the end effector actually orbits the upper arm end. Such a construction makes for a more complicated drive system for the eccentrically mounted end effector which contributes to larger size and weight as well as increased cost. Another shortcoming revealed in operational situations is the added difficultly for the human operator in aiming or positioning the end effector in its eccentric orbit. 
       SUMMARY OF THE INVENTION 
       [0003]    It is therefore an object of this invention to provide an improved mobile, remotely controlled robot. 
         [0004]    It is a further object of this invention to provide such an improved mobile, remotely controlled robot which has a more compact, lighter, smaller and lower cost robot arm end effector mechanism. 
         [0005]    It is a further object of this invention to provide such an improved mobile, remotely controlled robot which is easier for the human operator to aim or position. 
         [0006]    It is a further object of this invention to provide such an improved mobile, remotely controlled robot which orients the end effector in line with the robot arm. 
         [0007]    The invention results from the realization that an improved robot arm end effector mechanism for a mobile, remotely controlled robot which is smaller, more compact, less complex and easier to operate can be achieved with a roll motor unit fixed to the robot arm housing for rotating an end effector bearing sleeve and an end effector motor unit rotatable with the bearing sleeve for operating the end effector. 
         [0008]    The subject invention, however, in other embodiments, need not achieve all these objectives and the claims hereof should not be limited to structures or methods capable of achieving these objectives. 
         [0009]    This invention features a robot arm end effector mechanism for a mobile, remotely controlled robot including an arm housing, an end effector bearing sleeve rotatable relative to the arm housing, a roll motor unit, fixed to the arm housing and having a roll drive axis, for rotating the bearing sleeve, and an end effector motor unit having an end effector drive axis and being fixed to and rotatable with the bearing sleeve for operating the end effector. 
         [0010]    In a preferred embodiment the bearing sleeve may be rotatable inside of the arm housing. The bearing sleeve may be coaxial with the arm housing. The roll motor unit may be within the arm. The end effector motor unit may be within the bearing sleeve. Each motor unit may include a motor and a gear reducer. The bearing sleeve and arm housing may be elongate cylinders. The axes of the motor units may be parallel. The axes of the motor units may be coaxial. The robot arm end effector mechanism may further include a slip ring unit interconnected between the arm housing and bearing sleeve for communicating electric power to the end effector motor unit. The end effector may be a gripper. The gripper may include two fingers each driven by a gear and a drive gear for driving the gears and the end effector motor unit may drive the drive gear. 
         [0011]    This invention also features a robot arm end effector mechanism for a mobile, remotely controlled robot including a robot arm housing, an end effector bearing sleeve within, coaxial with and rotatable relative to the arm housing, a roll motor unit within and fixed to the arm housing and having a roll drive axis for rotating the bearing sleeve, and an end effector motor unit within and fixed to the bearing sleeve and having an end effector drive axis for operating the end effector; the roll drive axis and end effector drive axis are coaxial. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         [0012]    Other objects, features and advantages will occur to those skilled in the art from the following description of a preferred embodiment and the accompanying drawings, in which: 
           [0013]      FIG. 1  is a schematic three-dimensional view of a conventional mobile, remotely controlled robot including lower and upper arms and an end effector; 
           [0014]      FIG. 2  is a diagrammatic, three dimensional exploded view of an upper arm end effector mechanism according to this invention; 
           [0015]      FIG. 3  is a schematic, side, cross-sectional elevation of the arm end effector mechanism of  FIG. 2 ; 
           [0016]      FIG. 4  is a schematic, top, cross-sectional view of one example of an end effector that can be used; 
           [0017]      FIG. 5  is a diagrammatic, three dimensional, exploded view of the roll motor unit of  FIGS. 2 and 3 ; 
           [0018]      FIG. 6  is a diagrammatic, three dimensional, exploded view of the end effector motor unit of  FIGS. 2 and 3 ; and 
           [0019]      FIG. 7  is a diagrammatic, three dimensional, exploded view of the slip ring assembly of  FIGS. 2 and 3 ; 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0020]    Aside from the preferred embodiment or embodiments disclosed below, this invention is capable of other embodiments and of being practiced or being carried out in various ways. Thus, it is to be understood that the invention is not limited in its application to the details of construction and the arrangements of components set forth in the following description or illustrated in the drawings. If only one embodiment is described herein, the claims hereof are not to be limited to that embodiment. Moreover, the claims hereof are not to be read restrictively unless there is clear and convincing evidence manifesting a certain exclusion, restriction, or disclaimer. 
         [0021]      FIG. 1  shows a mobile, remotely controlled robot  10  driven by tracks  12   a  and  12   b  in accordance with one particular example of a robot in accordance with the subject invention. Robot  10  includes deployable mast  14 , camera  16 , light  18 , antennas  20   a  and  20   b , and arm assembly  22 . Arm assembly  22  includes lower arm  24  and upper arm  26 . Lower arm  24  is able to pitch up and down but it does not turn. Upper arm  26  pitches with respect to lower arm  24  and is driven by chain drive  28  extending along lower arm  24 . Microphone  30  is on upper arm  26  as is end effector  32  which rotates via wrist  34 . Camera  36  is typically aimed at end effector  32 . Operator control unit  40  is used to wirelessly control robot  10  as is known in the art. The various images captured by the cameras of the robot may be displayed on view screen  41 . 
         [0022]    The robot arm—end effector mechanism  100 ,  FIG. 2 , including upper arm  26  and end effector  32   a  are shown to more advantage in the schematic three dimensional exploded view of  FIG. 2 . There upper arm tube  102  fits over the reduced section  104  of upper elbow sleeve  106 . Roll motor unit  108  includes motor  110 , gear reducer  112 , and roll motor mount  114 . Output shaft  116  of roll motor unit  108  includes a key  118  which engages with yoke  120  in slip ring sleeve  122 , all of which are disposed inside of upper arm tube  102 . At the distal end of upper arm tube  102  is bearing sleeve  124  which includes end effector motor unit  126  including motor  128  and gear reducer  130 . The output shaft  132  contains a key  134  which engages with a drive gear in end effector  32   a . End effector  32   a  mounts to end effector motor unit  126  through engagement of its collar  136 . Retainer rings  138  and sealing O-ring  140  retain and seal motor unit  126  into arm  102 . Note that the roll drive unit  108 , upper arm tube  102 , bearing sleeve  124 , end effector motor unit  126 , and end effector  32   a  are all coaxial on axis  150 . 
         [0023]    The structure can perhaps be better understood by reference to  FIG. 3 , which is a cross sectional view showing that upper elbow sleeve  106  supports upper arm tube  102  in a fixed relationship via screws  152  and that roll motor unit  108  including motor  10  and gear reducer  112  are also fixed to upper arm tube  102  by means of roll motor mount  114  through screws  154 . Slip ring  160  is mounted within slip ring sleeve  122  about shaft  162  which extends from yoke  120 . Shaft  162  contains key  164  which fixes it to roll drive sleeve  123  by engaging slot  125  in roll drive sleeve  123 . Roll drive sleeve  123  is fixed to roll bearing sleeve  124  such as by screws  170  so that roll drive sleeve when rotated by the roll motor unit  108  through shafts  116  and  162  will rotate the entire bearing sleeve  124  containing end effector motor unit  126  including motor  128  and gear reducer  130 . Again it can be seen that all of the components, roll motor unit  108 , end effector motor unit  124 , upper arm tube  102 , and end effector  32   a  are all coaxial about the axis  150 . 
         [0024]    End effector  32   a ,  FIG. 4 , may be any type of device required to perform the robot&#39;s designated tasks. In this particular example, end effector  32   a  is implemented with a gripper having fingers  180 ,  182  which are fixed to pivot pins  184 ,  186  that rotate with, for example, worm gears  188 ,  190  driven by a drive gear such as worm  192  that engages with the key  134  and output shaft  132  of end effector motor unit  126 . Roll motor unit  108  is shown in greater detail in  FIG. 5  including roll motor  110 , gear reducer  112 , output shaft  116 , and roll motor mount  114 . Key  118  has key lock screws  200  and  202  and mounting screws  204  for fixing roll motor unit  108  to roll motor mount  114 . End effector motor unit  126 ,  FIG. 6 , is shown with the roll drive sleeve  123 , motor  128 , and gear reducer  130  inside of bearing sleeve  124 . Mounting collar  210  is part of bearing sleeve  124  and screws  212 , for example, may fix reducer  130  to  124 . Set screws  214  fix key  134  to shaft  132 . Slip ring  160  details are shown more specifically in  FIG. 7  where roll shaft  162  mounts through slip ring  160  and slip ring spacer  220  while slip ring  160  mounts inside of slip ring mount  122 . Key  164  is fixed to shaft  162  by set screws  222 . 
         [0025]    Although specific features of the invention are shown in some drawings and not in others, this is for convenience only as each feature may be combined with any or all of the other features in accordance with the invention. The words “including”, “comprising”, “having”, and “with” as used herein are to be interpreted broadly and comprehensively and are not limited to any physical interconnection. Moreover, any embodiments disclosed in the subject application are not to be taken as the only possible embodiments. 
         [0026]    In addition, any amendment presented during the prosecution of the patent application for this patent is not a disclaimer of any claim element presented in the application as filed: those skilled in the art cannot reasonably be expected to draft a claim that would literally encompass all possible equivalents, many equivalents will be unforeseeable at the time of the amendment and are beyond a fair interpretation of what is to be surrendered (if anything), the rationale underlying the amendment may bear no more than a tangential relation to many equivalents, and/or there are many other reasons the applicant can not be expected to describe certain insubstantial substitutes for any claim element amended. 
         [0027]    Other embodiments will occur to those skilled in the art and are within the following claims.