Abstract:
A mobile manipulation system comprising: 
     a base; 
     at least one mobility component mounted to said base for rendering said base mobile; 
     a platform; 
     at least one robotic manipulator arm mounted to said platform; and 
     an elevator mechanism movably supporting said platform on said base.

Description:
REFERENCE TO PENDING PRIOR PATENT APPLICATION 
       [0001]    This patent application claims benefit of pending prior U.S. Provisional Patent Application Ser. No. 61/866,935, filed Aug. 16, 2013 by William T. Townsend for MOBILE MANIPULATOR WITH VERTICAL LIFT (Attorney&#39;s Docket No. BARRETT-6 PROV), which patent application is hereby incorporated herein by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    This invention relates to robotic systems in general, and more particularly to mobile manipulation systems. 
       BACKGROUND OF THE INVENTION 
       [0003]    Mobile manipulation is a relatively new field in robotics. In mobile manipulation, one or more robotic manipulator arms are attached to a mobile base that can support the loads of the robotic manipulator arm(s), rather than fixing the robotic manipulator arm(s) permanently to a building structure. These mobile manipulators have new applications that would not be possible without mobility, most notably their ability to navigate through peopled spaces. However, existing mobile manipulation systems suffer from a number of limitations which have yet to be addressed. 
         [0004]    For example, it is important that the robotic manipulator arm(s) be able to reach the floor, yet also be able reach up high into overhead cabinets. These robotic manipulator arms (partly for safety) tend to be about 1 meter or less in length, so system designers have had to choose between covering the vertical range from floor level to countertop level or covering countertop level to overhead cabinet level, but not the full range from floor level to overhead cabinet level. 
         [0005]    Some mobile manipulators, such as those made by Willow Garage of Palo Alto, Calif., USA and Meka Robotics of San Francisco, Calif., USA, add extra degrees of freedom to the robotic manipulator arm(s) that are carried by the mobile base. However, the base itself remains fixed vertically and these products do not cover a sufficient vertical range as is needed to reach from the floor to overhead cabinets. 
         [0006]    Accordingly there is a need for a new and improved mobile manipulation system with an expanded vertical range such that it is able to reach from the floor to overhead cabinets. 
       SUMMARY OF THE INVENTION 
       [0007]    The present invention provides a new and improved mobile manipulation system which addresses some or all of the foregoing problems commonly associated with existing mobile manipulation systems. 
         [0008]    In one preferred form of the invention, there is provided a mobile manipulation system comprising: 
         [0009]    a base; 
         [0010]    at least one mobility component mounted to said base for rendering said base mobile; 
         [0011]    a platform; 
         [0012]    at least one robotic manipulator arm mounted to said platform; and 
         [0013]    an elevator mechanism movably supporting said platform on said base. 
         [0014]    In another preferred form of the invention, there is provided a mobile robotic platform comprising an elevator mechanism which raises and lowers a platform relative to a base, and wherein the base is mobile and the platform comprises at least one robotic manipulator arm. 
         [0015]    In another preferred form of the invention, there is provided a method for accessing an elevated space, the method comprising: 
         [0016]    providing a mobile manipulation system comprising:
       a base;   at least one mobility component mounted to said base for rendering said base mobile;   a platform;   at least one robotic manipulator arm mounted to said platform; and   an elevator mechanism movably supporting said platform on said base; and       
 
         [0022]    actuating said elevator mechanism so as to elevate the platform. 
         [0023]    In another preferred form of the invention, there is provided a method for accessing an elevated space, the method comprising: 
         [0024]    providing a mobile robotic platform comprising an elevator mechanism which raises and lowers a platform relative to a base, and wherein the base is mobile and the platform comprises at least one robotic manipulator arm; and 
         [0025]    operating the elevator mechanism so as to elevate the platform. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0026]    These and other objects and features of the present invention will be more fully disclosed or rendered obvious by the following detailed description of the preferred embodiments of the invention, which is to be considered together with the accompanying drawings wherein like numbers refer to like parts, and further wherein: 
           [0027]      FIG. 1  is a schematic view of a novel mobile manipulation system formed in accordance with the present invention, wherein the mobile manipulation system has its elevator mechanism in a lowered position and showing a robotic manipulator arm in various positions; 
           [0028]      FIG. 2  is a schematic view of the novel mobile manipulation system of  FIG. 1 , wherein the mobile manipulation system has its elevator mechanism shown in a raised position and showing the robotic manipulator arm in various positions; 
           [0029]      FIG. 3  is a schematic view of the novel mobile manipulation system of  FIG. 1 , wherein the mobile manipulation system has its elevator mechanism in the lowered position and showing the robotic manipulator arm picking up an object off the ground; 
           [0030]      FIG. 4  is a schematic view of the novel mobile manipulation system of  FIG. 3 , wherein the mobile manipulation system has its elevator mechanism shown in a position intermediate the lowered and raised positions; 
           [0031]      FIG. 5  is a schematic view of the novel mobile manipulation system of  FIG. 3 , wherein the mobile manipulation system has its elevator mechanism shown in its raised position; 
           [0032]      FIG. 6  is a schematic view of an exemplary elevator mechanism, with the exemplary elevator mechanism being shown in its lowered position; and 
           [0033]      FIG. 7  is a schematic view of an exemplary elevator mechanism, with the exemplary elevator mechanism being shown in its raised position. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0034]    The present invention provides a new and improved mobile manipulation system which addresses some or all of the foregoing problems commonly associated with existing mobile manipulation systems. 
         [0035]    More particularly, and looking now at  FIGS. 1-5  the present invention provides a new and improved mobile manipulation system  5  which comprises a base  10 , a platform  15  and an elevator mechanism  20  that movably supports platform  15  on base  10  so that platform  15  may be moved vertically relative to base  10  while remaining laterally stiff. High maneuverability mobility components  25  (e.g., Mecanum wheels of the sort available from AndyMark, Inc. of Kokomo, Ind., USA and/or VEX Robotics, Inc. of Greenville, Tex., USA or “Omniwheels” of the sort available from AndyMark, Inc. of Kokomo, Ind., USA and/or VEX Robotics, Inc. of Greenville, Tex., USA) are mounted to base  10 , so as to allow mobile manipulation system  5  to move about complicated or congested areas (e.g., peopled areas), as is more particularly described below. Platform  15  is provided with a robotic manipulator arm  30  which is movably mounted to platform  15 , as is also more particularly described below. A robotic hand  35  is mounted to robotic manipulator arm  30  at the free end of robotic manipulator arm  30 . When elevator mechanism  20  is actuated, as described below, platform  15  is moved vertically away from base  10 , thereby increasing the vertical range of mobile manipulation system  5 . 
         [0036]    More particularly, and looking now at  FIGS. 1-7 , elevator mechanism  20  may comprise a “scissors lift” (or “scissors jack”) mechanism  40 . Scissors lift mechanism  40  allows platform  15  to be moved vertically relative to base  10  while remaining laterally stiff. In this form of the invention, scissors lift mechanism  40  is used to move platform  15  vertically, away from or closer to base  10 . Scissors lift mechanism  40  generally comprises two scissors pairs, one on each side of base  10 , where each scissors pair itself comprises a pair of crossed arms  45 ,  50 , with one end of each arm being pivotally connected to either base  10  or platform  15 , and with the other end of each arm being slidably connected to the other of base  10  or platform  15 , and with the pair of crossed arms  45 ,  50  being pivotally connected to each other intermediate their length. Upon actuation, e.g., by a servo motor  55 , scissors lift mechanism  40  moves from the position shown in  FIG. 6  (with platform  15  disposed relatively close to base  10 ) to the position shown in  FIG. 7  (with platform  15  vertically displaced from base  10 ). In one preferred configuration, the difference in the distance between platform  15  and base  10  when scissors lift mechanism  40  is in its raised position (i.e., the position shown in  FIG. 7 ) is about 400 millimeters. 
         [0037]    By virtue of this construction, platform  15  can move vertically (relative to base  10 ) so as to expand the vertical range or reach of mobile manipulation system  5 . For example, platform  15  of mobile manipulation system  5  can be lowered to allow robotic hand  35  of robotic manipulator arm  30  to reach an object  37  disposed on the floor (see  FIG. 3 ) or platform  15  of mobile manipulation system  5  can be raised so that robotic hand  35  of robotic manipulator arm  30  can reach to a height of overhead cabinets (see  FIGS. 4 and 5 ). 
         [0038]    As discussed above, platform  15  comprises a robotic manipulator arm  30  which is movably mounted to platform  15 . In one preferred form of the invention, robotic manipulator arm  30  may comprise a 7-degree-of-freedom robotic manipulator arm, such as the WAM® Arm manufactured by Barrett Technology, Inc. of Newton, Mass., USA. 
         [0039]    As also discussed above, robotic hand  35  is mounted to the free end of robotic manipulator arm  30 . Robotic hand  35  permits mobile manipulation system  5  to grasp, hold and release an object (e.g., such as the object  37  shown in  FIGS. 3-5 ). In one preferred form of the invention, robotic hand  35  may comprise a multi-fingered grasper, such as the BarrettHand™ manufactured by Barrett Technology, Inc. of Newton, Mass., USA. 
         [0040]    In one preferred form of the invention, platform  15  also comprises an array of sensors  60  positioned thereon. Sensors  60  provide feedback to a control unit (not shown), which in turn allows the control unit to issue commands to various components of mobile manipulation system  5  (e.g., to mobility components  25 , robotic manipulator arm  30 , robotic hand  35 , etc.) which will govern the actions of mobile manipulation system  5  and/or the components thereof in a manner that is known in the art. By way of example but not limitation, sensors  60  may be cameras, ultrasound devices, etc. Note also that the control unit (not shown) may be mounted on mobile manipulation system  5  or may be located at a remote location and may communicate with mobile manipulation system  5  (e.g., by wire or wireless communications). 
         [0041]    As discussed above, base  10  comprises mobility components  25 . Mobility components  25  preferably comprise Mecanum wheels or “Omniwheels” which enable high maneuverability in cluttered and confined workspaces such as those of peopled environments (e.g., a home or office). Such wheels allow mobile manipulation system  5  to execute the necessary movements to allow for operation in such environments. Alternatively, mobility components  25  may comprise other types of wheels, tank-type treads, belt drives, or other types of units configured to provide movement to base  10  (and hence mobile manipulation system  5 ). 
         [0042]    In addition, base  10  comprises a power source (e.g., batteries) and other mechanical structures to support operation of mobile manipulation system  5 . The positioning of batteries and other heavy mechanical components in base  10  (i.e., in the portion of mobile manipulation system  5  that is close to the ground) provides for increased stability of mobile manipulation system  5  by preserving a lower center of gravity. This is of significant benefit, particularly when platform  15  is in its raised position and/or robotic manipulator arm  30  is extended in an upward position. In addition, in some embodiments of the present invention, mobile manipulation system  5  may be configured such that mobility parameters (e.g., speed, steerability, etc.) of the mobile manipulation system  5  are restricted as the vertical profile (e.g., the height of body  10  and/or the height of robotic manipulator arm  30 ) increases. 
         [0043]    The novel mobile manipulation system  5  of the present invention allows mobile manipulation system  5  to fulfill three important objectives: (1) it enables mobile manipulation system  5  to access an object off the floor; (2) it enables mobile manipulation system  5  to access overhead cabinets; (3) it allows the length of robotic manipulator arm  30  to remain at a length that is within desired safety parameters. 
         [0044]    It will be appreciated that while the exemplary embodiment of the invention shown in  FIGS. 1-7  shows the novel mobile manipulation system  5  having one 7-degree-of-freedom manipulator arm with a robotic multi-finger grasper hand, other embodiments of the present invention may include any number of robotic manipulator arms, with the robotic manipulator arms (and robotic hands) being of any kinematic configuration and function. Similarly, while sensor array  60  is shown at a particular location on platform  15  in the exemplary embodiment shown in  FIGS. 1-5 , it will be appreciated that sensor array  60  may be located elsewhere on platform  15  and/or on other parts of mobile manipulation system  5 , or that sensors  60  may be disposed at multiple locations on mobile manipulation system  5 . Also, while the actuating mechanism for elevator mechanism  20  has been described as a servo motor  55 , it will be understood by those skilled in the art that other means for actuating elevator mechanism  20  may be used (e.g., the actuator may be an electromagnetic device, a rotary electromagnetic motor, a linear electromagnetic motor, a hydraulic device, a pneumatic device, etc.). 
       Modifications of the Preferred Embodiments 
       [0045]    It should be understood that many additional changes in the details, materials, steps and arrangements of parts, which have been herein described and illustrated in order to explain the nature of the present invention, may be made by those skilled in the art while still remaining within the principles and scope of the invention.