Abstract:
A compact, low profile omnidirectional drive and steering unit that, in one embodiment, utilizes a single, centrally located wheel, mounted on a drive shaft, upon which is also mounted a tapered pinion gear. The pinion gear on the drive shaft meshes with a ring shaped beveled worm gear contained within the outer housing of the gear unit that surrounds the centrally located wheel. At one side of the outer housing is a worm drive that meshes with the ring shaped and beveled worm gear. Rotation of the worm drive causes rotation of the ring shaped worm gear, which causes the drive shaft mounted pinion gear to turn, which turns the drive wheel to provide driving power for whatever vehicle or system of which the unit is a part. A steering and timing gear is mounted on the lower surface of the unit to provide steering capability.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Application 61/145,543, filed Jan. 17, 2009, U.S. Application 61/248,448, filed Oct. 3, 2009, and U.S. Application 61/258,006, filed Nov. 4, 2009, the contents of each of which are incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to a wheel drive and steering unit for, in one embodiment, automatic guided vehicles (AGVs) and other semi-automatic or manually controlled vehicles. More particularly, the present invention relates to a compact and low profile drive and steering unit that has a unique ability to fully rotate a vehicle around its central vertical axis, and to drive or move a vehicle in any direction without altering the orientation of the vehicle. 
     BACKGROUND OF THE INVENTION 
     Conventional AGVs rely upon gear units that house separate drive and steering components that are adjacent to a load carried by a vehicle. For example, conventional AGVs employ two turnable and two non-turnable wheels, much like a forklift, where the drive and steering mechanisms are adjacent to the load. That design simplifies the mechanical components of the system, but limits the amount of the load a vehicle can carry and the maneuverability of the vehicle. The load is limited because the placement of the drive and steering components adjacent to the load increases the top-heaviness of the vehicle. Maneuverability is constrained because only two wheels are capable of turning. 
     In addition, existing omnidirectional drive and steering units are relatively delicate in construction, large in design, and provide minimal power for steering, drive, and load bearing functions relative to the overall size of the unit. 
     SUMMARY OF THE INVENTION 
     The present invention discloses, in one embodiment, a compact wheel drive and steering system that is preferably placed under a load, or in one example a vehicle, rather than adjacent thereto, and that is capable of rotating a vehicle to any degree around its central vertical axis, and of moving a vehicle in any direction without altering its orientation or that of a load. 
     The placement of the system under a vehicle increases the load capability, and the omnidirectional nature of the drive and steering system improves maneuverability and reduces the space or area necessary for vehicle operation. For example, an AGV equipped with one or more omnidirectional steering and drive units of the present invention working in a coordinated fashion, operating in an automated parking facility, can slide under an automobile because of the placement and compactness of the drive and steering units, lift the automobile and turn around without using a turntable or making a U-turn in an arc, travel for a distance and deposit the automobile in a storage space or aisle that is normal to the direction of the vehicle without changing the orientation of the vehicle or using floor space for the arc required for a vehicle turning radius. 
     The omnidirectional drive and steering system of the present disclosure provides an AGV or other vehicle with multidirectional travel capability, the ability to turn 360° so that vehicles can be driven forward into the structure and also driven forward when exiting the structure, and a more efficient mode of maneuvering automobiles to and from storage within the system which can increase system efficiency and significantly decrease costs associated with storage system footprint, construction and maintenance. 
     One aspect of the invention is to provide a drive and steering unit that is very low profile and compact, and that is capable of transporting heavy loads. Another aspect is to provide a drive and steering unit that does not require changing gears to reverse directions. Another aspect is to provide a device where the drive and steering unit can be placed directly below the load providing a 360° turning capability within the diameter of the footprint of the load. Another aspect is to provide a drive function that operates independent of the steering function within a low profile, compact housing. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are incorporated in and form a part of this specification, illustrate certain embodiments of an omnidirectional drive and steering unit and together with the description, serve to explain certain aspects of the principles of this application. 
         FIG. 1  is an exploded view of an omnidirectional drive and steering unit of the present invention. 
         FIG. 2  is an isolated view of one aspect of an omnidirectional drive and steering unit attached to drive and steering motors. 
         FIG. 3  is an exploded view of one aspect of an upper case assembly of the invention. 
         FIG. 4  is a flow diagram of the assembly of one embodiment of one aspect of the omnidirectional drive and steering unit of the invention. 
         FIG. 5  is a flow diagram of the assembly of one embodiment of an upper case assembly of the invention. 
         FIG. 6  is an exploded view of one embodiment of a wheel pinion gear and wheel housing assembly of the invention. 
         FIG. 7  is a flow diagram of the assembly of one embodiment of a wheel and pinion gear assembly of the invention. 
         FIG. 8  is a flow diagram of the assembly of one embodiment of a wheel housing assembly of the invention. 
         FIG. 9  is an exploded view of one embodiment of a worm gear assembly of the invention. 
         FIG. 10  is an exploded view of one embodiment of a lower case assembly of the invention. 
         FIGS. 11A and 11B  are a flow diagram of the assembly of one embodiment of a case assembly of the invention. 
         FIG. 12  is a top view of the omnidirectional drive and steering unit, constructed in accordance with the present invention; 
         FIG. 13  is a cross-section taken along line  13 - 13  of  FIG. 12 . 
         FIG. 14  is a perspective view taken from the bottom of one embodiment of certain sections of the omnidirectional drive and steering unit of the invention. 
         FIG. 15  is a perspective view taken from the side of one embodiment of certain sections of the omnidirectional drive and steering unit of the invention. 
         FIG. 16  is a perspective view taken from the bottom of one embodiment of certain sections of the omnidirectional drive and steering unit of the invention. 
         FIG. 17  is a bottom view of one embodiment of an AGV including a pair of omnidirectional drive and steering units. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     This disclosure describes the best mode or modes of practicing the invention as presently contemplated. This description is not intended to be understood in a limiting sense, but provides an example of the invention presented solely for illustrative purposes by reference to the accompanying drawings to advise one of ordinary skill in the art of the advantages and construction of the invention. In the various views of the drawings, like reference characters designate like or similar parts. 
       FIG. 1  is an exploded view of one embodiment of an omnidirectional drive and steering unit  10  (hereinafter referred to as unit  10 ) generally comprising an upper case assembly  12 , a lower case assembly  16 , a wheel housing assembly  14  enclosing a wheel  54 , and a drive assembly  18 . One embodiment of a method of assembly of each generally-referenced region is further illustrated in the figures that follow, where  FIG. 3  illustrates one embodiment of an assembly of the upper case assembly  12 ,  FIG. 10  illustrates one embodiment of an assembly of the lower case assembly  16 ,  FIG. 6  illustrates one embodiment of an assembly of the wheel housing assembly  14 , and  FIG. 9  illustrates one embodiment of an assembly of the drive assembly  18 . As will be described in more detail below, the upper and lower case assemblies  12 ,  16  are preferably fixed relative to an AGV ( FIG. 17 ), for example, to which the unit  10  is attached. The drive assembly  18  is adapted for rotating the wheel  54  either forward or backward without switching drive gears, while the wheel housing assembly  14  is rotatably steered within the upper and lower case assemblies  12 ,  16  through engagement with a steering gear  90 . As will be further described below, the wheel  54  can be driven and steered or turned independently or simultaneously as desired. 
       FIG. 2  illustrates one embodiment of a bottom view of the unit  10  showing the steering gear  90  coupled to a steering motor  200  via a belt  210 , and a drive motor  250  coupled to a drive shaft  102  of the drive assembly  18  (see  FIG. 1 ) through a coupling  260 . While the embodiment of  FIG. 2  shows the steering gear  90  being driven by a belt  210 , it will be appreciated that the steering gear  90  could be driven by other means, such as by another gear coming off of the steering motor  200 , or through a direct connection with the steering motor  200 . Having the steering motor  200  laterally spaced from the steering gear  90  and the rest of the unit  10  aids in maintaining a low profile for the unit  10 . The steering motor  200  and drive motor  250  are also preferably independent from each other so that the unit  10  can be independently driven and steered. Each motor  200 ,  250  is preferably associated with a steering assembly control system  220 , a drive assembly control system  270  that is preferably associated with a processor (not shown) that guides the movement and direction of the unit  10  and of an AGV or the like ( FIG. 17 ). If multiple units  10  are employed in an AGV or the like ( FIG. 17 ), then each unit  10  would preferably have its own steering and drive motor assemblies so that each unit  10  can be independently driven and steered relative to the other units  10 . 
     Various methods of assembly of each region will now be described, it being understood that certain aspects of assembly are described and that other aspects and embodiments of assembly are contemplated. Furthermore, while certain methods of construction are described herein, it will be appreciated that such methods of assembly are not limited to the embodiments as shown, or the described order of assembly, but that various methods of assembly in various orders are contemplated. 
       FIG. 3  is an exploded view of the upper case assembly  12 , which includes the drive gear assembly consisting of worm gear  24 , and bevel gear  26 , and  FIG. 4  is a flow diagram illustrating one embodiment of assembling the same. In one embodiment, outside diameter contact bearing  30  is pressed into the bevel gear  26  and held in place by snap ring  32  after the shape of the snap ring is adjusted if necessary. The snap ring  32  fits within a snap ring groove (not shown) on the bevel gear  26 . Dowel pins  34  are preferably inserted into the bevel gear  26  for alignment with the gear mounting ring  36  when the gear mounting ring  36  is pressed onto the bevel gear  26 . The dowel pins  34  are preferably pressed flush to the surface of the gear mounting ring  36 , and then the bevel gear  26  is attached to the gear mounting ring  36  by fasteners such as Allen head screws  38  for example. Of course, other types of fasteners may be used. Additional dowel pins  34  are used to align the worm gear  24  with the assembly of the bevel gear  26  and gear mounting ring  36 , which are then secured to each other with fasteners such as machine screws  40  to form the drive gear assembly of the worm gear  24 , bevel gear  26  and gear mounting ring  36 . Top wheel support  76  (see  FIG. 1 ) is inserted into the assembly of the worm gear  24 , gear mounting ring  36  and bevel gear  26  and aligned with such assembly with dowel pins. 
       FIG. 5  is a flow diagram illustrating the upper case assembly  12 , where outside diameter contact bearing  30  is placed on the upper case  28  and pressed into position below the snap ring groove  83  and snap ring  84  ( FIG. 1 ). The shape of the snap ring  84  is adjusted as required and inserted into the snap ring groove  83  in the upper case  28 . Gasket sealant or the like is preferably applied to the mating surfaces of the bearing cap  42  and top wheel support  76 . The bearing cap  42  is then aligned with and secured to the top wheel support  76  with bearing cap mounting fasteners or screws  44 . As illustrated in  FIGS. 1 and 3 , top cover  46  is secured to the upper case  28  with mounting fasteners or screws  48 . 
       FIG. 6  is an exploded perspective of the drive wheel  54 , wheel drive shaft gear  56  and wheel housing components  14 . The wheel drive shaft  58  is shown below the drive wheel  54  along with a long key  60  that engages a slot  55  in the drive wheel  54  and a short key  62  that engages a slot  57  in the wheel drive shaft gear  56 . Above the drive wheel  54  is a snap ring  64 , laminated shim  66  and drive shaft bearing  68 . On the other side of the drive wheel  54  is a laminated shim  66 , drive shaft bearing  68 , oil seal  70 , wheel drive shaft gear  56  and snap ring  64 . To the left of the wheel drive shaft  58  in  FIG. 6  is lower wheel bearing housing  72 , and to the right is an upper wheel bearing support  74  and the top wheel support  76  (see also  FIG. 1 ). The lower wheel bearing housing  72 , upper wheel bearing support  74  and the top wheel support  76  are positioned by long dowel pins  78  and attached by fasteners such as, for example, machine screws  80 . The top case outside diameter bearing  82  and the snap ring  84  are shown in alignment with the top wheel support  76 . 
       FIG. 7  is one embodiment of a flow diagram of the assembly of the wheel and pinion gear assembly of  FIG. 6 . The wheel drive shaft  58  is pressed into the drive wheel  54  along with the long key  60  in the keyway (not shown on the drive shaft) until the snap ring groove  59  on the distal end of the wheel drive shaft  58  passes beyond the outside of the drive wheel  54 . The snap ring  64  is installed into the snap ring groove  59 , the drive wheel  54  is pressed against the snap ring  64 , and then laminated shim  66  is placed on the wheel drive shaft  58  on top of the snap ring  64 . Another laminated shim  66  is placed on the wheel drive shaft  58  on the opposite side of the drive wheel  54 , where the distance between the laminated shims  66  on either side of the drive wheel  54  is preferably approximately 3.125 inches. Other spacing is contemplated depending on the size of the drive wheel  54  and the environment, and some adjustment of the laminated shims  66  may be required. The drive shaft bearings  68  are positioned on the drive shaft  58  on either side of the drive wheel  54 . The pinion gear  56  is placed on the wheel drive shaft  58  with a snap ring  64 , although preferably not initially using the short key  62  to make corrections in the position of the pinion gear  56  by adjusting the laminated shims  66  on either side of the drive wheel  54 . The pinion gear  56  can be removed from the wheel drive shaft  58  to install the oil seal  70  over the wheel drive shaft  58 , and then the pinion gear  56  is re-seated on the drive shaft  58  with the short key  62  and snap ring  64 . All above-mentioned parts are preferably lubricated at assembly as required. 
       FIG. 8  is one embodiment of a flow diagram discussing the wheel housing assembly  14  shown in  FIG. 6 . Mating surfaces of the top wheel support  76  and upper wheel bearing support  74  are preferably coated with gasket sealant and then the top wheel support  76  is positioned over the upper wheel bearing support  74  using alignment dowel pins  78 . The wheel and pinion gear assembly described in  FIGS. 6 and 7  is placed into the upper wheel bearing support  74  and the lower wheel bearing housing  72  is then pressed onto the dowel pins  78  extending from the upper wheel bearing support  74 . Thereafter, the top wheel support  76 , upper wheel bearing support  74  and the lower wheel bearing housing  72  are secured by, for example, machine screws  80 . 
       FIG. 9  is an exploded view of one embodiment of the drive assembly  18  comprising a worm assembly  98  including a worm  100  and worm shaft  102  with tapered bearings  104 ,  106  and shaft seals  112 ,  114  at either end. While the worm  100  and worm shaft  102  are shown as a single machined part, it will be understood that other methods of manufacture and assembly are contemplated. In addition, while a drive assembly  18  based on a worm drive is shown and described, it will be appreciated that other drive systems will be operable. The worm assembly  98  is attached to the upper and lower cases  28 ,  86  through the use of worm seal mounting plates  108  and  110  that are secured to the upper and lower cases  28 ,  86  with threaded fasteners  116  and lock washers  118  or the like. Other methods of securing and fastening are contemplated. 
       FIG. 10  is an exploded view of one embodiment of the lower case assembly  16  ( FIG. 1 ) or steering gear assembly, comprising the lower case  86 , lower case seal  88  and the steering gear  90 . The steering gear  90  is attached to the lower wheel bearing housing  72  ( FIG. 1 ) with fasteners  92 , such as Allen head screws  92  for example, while other fasteners  94 , such as machine screws  94  for example, are used to attach the lower case  86  to the upper case  28  ( FIG. 1 ). As also shown in  FIGS. 1 ,  2  and  17 , while the steering gear  90  is disposed outside of the lower case  86  for engagement with a steering motor  200  or the like ( FIG. 2 ), the steering gear  90  also engages the wheel assembly  14  through fixed engagement with the lower wheel bearing housing  72 . 
       FIGS. 11A and 11B  describe one embodiment of an assembly of the upper and lower cases  28 ,  86  of the unit  10 . It will be appreciated that while one non-limiting sequence of assembly is described in some detail, other methods of assembly will be contemplated. First, the lower case oil seal  88  is pressed into the lower case  86  ( FIGS. 1 ,  10 ). The lower case  86  is then turned over on a work surface (not shown) for applying gasket sealant to the mating edges of both the upper case  28  and the lower case  86  and for lightly greasing the seal mating surface where lower wheel bearing housing  72  meets the lower case oil seal  88  ( FIG. 1 ). Placing the lower case assembly  16  onto upper case assembly  12  and pressing the lip of the lower case oil seal  88  in around the edge of the lower wheel bearing housing  72  ensures an even fit and adequate seal. Machine screws  94 , for example, which join the upper case  28  to the lower case  86 , are tightened by first tightening the screws in the rectangular area above the worm  100  ( FIG. 1 ) until they are snug and the gasket cement squeezes out, and the remaining screws are tightened to secure the lower case  86  to the upper case  28 . The assembly of the upper and lower cases is turned over and it is determined where the pinion gear  56  is currently positioned relative to the bearing cap  42  and such location on the bearing cap  42  is marked. In accordance with one method, a series of punch marks in the bearing cap  42  roughly resembling an arrow shape are made using a hammer and center punch, for example, to mark the location directly over the pinion gear  56 . Thereafter, the worm shaft seal  112  ( FIG. 9 ) is advanced slightly onto the worm seal mounting plate  108  with the open side of the seal  112  going in towards a stop machined into the worm seal opening in the plate  108 . The worm shaft seal  112  and worm seal mounting plate  108  are then placed in an arbor press, with the worm seal side up for squaring and centering the worm seal mounting plate  108  under the arbor press, and the seal  112  is then pressed into the worm seal mounting plate  108 . The mounting plate  108  with seal  112  is then advanced or slid onto one side of the worm shaft  102  and aligned so that the screw holes  107  ( FIG. 9 ) in the worm seal mounting plate  108  align with the threaded holes  27 ,  87  ( FIG. 1 ) in the upper case  28  and lower case  86  assembly. Gasket sealant is then applied to the non-seal face of the worm seal mounting plate  108  and  110  and their mating surfaces on upper case  28  and lower case  86  assembly and the plates  108 ,  110  are attached by fasteners such as, for example, Allen head cap screws  116  ( FIGS. 1 ,  9 ). Dowel pins in dowel pin holes are placed in lower wheel bearing housing  72  and tapped with a hammer to seat as needed. A gear oil drain plug (not shown) is installed in the lower case  86  until the top of the drain plug is flush with the exterior of the lower case  86 . Dowel pin holes in the steering gear  90  are aligned with dowel pins in the lower wheel bearing housing  72  and hand pressed into place and then secured with, for example, flat head socket cap machine screws  92  and tightened in place ( FIGS. 1 ,  10 ). A bead of sealant (not shown) is placed around the top edge of the upper case  28  and then a preferably transparent top cover  46  is placed thereon. Fasteners  48 , such as Allen head screws  48  for example, are initially tightened to form a uniform and secure bond between the top cover  46  and upper case  28 , but not tightened so much so that the cover  46  is pressed all of the way down to touch the upper case  28 . Once the sealant has cured, usually in about one hour, the fasteners  48  can be tightened completely to form a secure connection between the top cover  46  and the upper case  28 . 
       FIG. 12  is a top view of one embodiment of the unit  10  showing the preferably transparent top cover  46 , upper case  28 , worm shaft  102  and worm seal mounting plates  108  and  110 . While the top cover  46  is illustrated with some transparency, it will be appreciated that he top cover  46  could also be semi-transparent, translucent, solid or a combination of the same as desired. 
       FIG. 13  is a cross-section taken along line  13 - 13  of  FIG. 12 , and illustrates the compact construction of the unit  10 . As the unit  10  is preferably to be incorporated into an AGV or the like, and in some situations the AGV would have to maneuver with very little height clearance, it is preferred that the height of the unit  10  taken along a central axis  120  through the wheel  54  and normal to the ground (not shown) is approximately four inches. Of course, other dimensions are contemplated for other environments and clearance considerations. 
       FIG. 14  is a perspective view taken from the bottom and  FIG. 15  is a perspective view taken from the side of one embodiment of certain sections of the unit  10 , other sections being omitted for purposes of illustrating and demonstrating the manner in which the drive assembly  18  drives the drive wheel  54 . Specifically, the worm  100  meshes with the worm gear  24  such that a rotation of the worm  100  along the axis of the worm shaft  102  causes an omnidirectional rotation of the worm gear  24  about a central axis  120  ( FIG. 13 ) of the unit  10 . The rotation of the worm gear  24  results in a rotation of the bevel gear  26  through the fixed assembly of the worm gear  24  with the bevel gear  26  via the gear mounting ring  36  (see, for example, the discussion of  FIG. 3 ). The pinion gear  56  meshes with the bevel gear  26  ( FIG. 14 ) such that rotation of the bevel gear  26  causes a rotation of the pinion gear  56  about the drive shaft  58  of the wheel  54 , which causes a rotation of the drive shaft  58  that drives the wheel  54  clockwise or counterclockwise (forward or backward) as desired. 
       FIG. 16  is a perspective view taken from the bottom of certain sections of the unit  10 , other sections being omitted for purposes of illustrating and demonstrating the manner in which the wheel  54  is steered. The wheel  54  is steered through the engagement of the steering gear  90  ( FIGS. 1 ,  10 ,  16 ) with the lower wheel bearing housing  72 , which is fixed to the upper wheel bearing support  74  and the top wheel support  76  (see  FIG. 6 ) to form part of the wheel housing assembly  14  ( FIG. 1 ). The wheel housing assembly  14  is rotatable within the upper and lower cases  28  and  86  via bearings  30 ,  82 ,  88  ( FIG. 1 ). Rotation of the wheel  54  and the wheel housing assembly  14  ( FIG. 1 ) is accomplished by rotation of the steering gear  90  ( FIGS. 2 ,  16 ), which causes the wheel housing assembly  14  to rotate along the central axis  120  ( FIG. 13 ) of the wheel  54  relative to the assembly of gear mounting ring  36 , bevel gear  26  and worm gear  24 . More specifically, omnidirectional rotation of the wheel housing assembly  14  is guided through the engagement of the pinion gear  56  with the bevel gear  26 , which occurs independently of the interaction of the drive assembly  18  with the pinion gear  56 . Thus, the pinion gear  56  functions to translate the rotation of the bevel gear  26  to the drive shaft  58  (see  FIG. 14 ) to drive the wheel  54 , and at the same time it functions to guide the rotation of the wheel  54  relative to the upper and lower cases  28  and  86  for turning the wheel about the axis  120  ( FIG. 13 ). The driving and steering of the wheel  54  can occur independently or simultaneously as desired and depending on the control systems  200 ,  270  that control the drive and steering motors  250 ,  200  ( FIG. 2 ). 
       FIG. 17  illustrates one embodiment of a bottom view of an AGV  300  or the like with two drive and steering units  310 ,  320 , each having a drive motor  312 ,  322  and a steering motor  314 ,  324 . The units  310 ,  320  are independently arranged to provide independent driving and steering of the wheels  316 ,  326  relative to each other and to the AGV  300 . While  FIG. 17  illustrates two units  310 ,  320 , it will be appreciated that any number of units can be implemented on an AGV or the like, such as, for example, one on each corner of the AGV if desired. 
     In one non-limiting embodiment, the omnidirectional drive and steering unit has a single, independently operating gear unit and housing surrounding a single, centrally located wheel, which due to the unique configuration of the unit assembly provides the ability for the wheel, and any support structure or vehicle it is a part of, to be turned for steering and drive purposes in any direction. This also includes the ability for the unit to drive and steer simultaneously, to stop and immediately reverse direction, and the ability of the wheel within the unit to be turned either clockwise or counterclockwise, in full circles or any portion thereof, either singly, or in conjunction with other similar omnidirectional drive and steering gear units. In addition, the unit is preferably designed to be very robust and to perform all of these operations while bearing a very large load and providing a significant amount of torque relative to the overall size of the unit. 
     Returning to  FIGS. 12 and 13 , it will be seen that the weight from a load (not shown) placed on the top of the unit  10  is conveyed to the wheel  54  through the mounting fasteners  48  connection to the upper and lower wheel bearing supports  74 ,  72 . This arrangement, coupled with the unique configuration of the laterally offset drive assembly  18  and driving gear arrangement that is coaxial with the central axis  120  of the wheel  54 , provides for a durable, compact construction that enables a large load to be placed directly on top of the unit  10  for omnidirectional movement of the load without altering the orientation of the load relative to the unit  10 . This is a significant departure from the conventional forklift-type arrangement where the load is separated from the drive and steering mechanisms. 
     In one non-limiting application, an AGV which picks up an automobile by lifting under the automobile&#39;s tires, carrying an automobile forward, backward or sideways (perpendicular to an automobile&#39;s normal forwards/backwards travel orientation) through travel lanes and other components of an automated storage system, uses four coordinated versions of the omnidirectional drive and steering units to move the automobile quickly and efficiently to and from storage locations while requiring the absolute minimum possible building space and system footprint to accommodate vehicles of the size desired. 
     In another non-limiting application, an AGV, with direction from other devices, sensors, measuring implements, or human intervention, implements the capabilities of the omnidirectional drive and steering units to easily and quickly shift relative location or orientation to a target item which is not situated exactly correctly relative to its normal pick up location. This system would eliminate the need for several adjustment maneuvers (similar to a three point turn) that are normally required to respond to a variation in pick up location, and could be used to handle irregularly shaped items or items which were placed imprecisely by imperfect human or mechanical operations. For example, items unloaded into an automated warehouse by human workers and not placed exactly “on center” in a loading area could be detected by sensors in the loading area and an AGV equipped with the units of present invention could shift as needed to correctly approach and acquire the target item, then shift back to center as needed to transport the acquired item to the appropriate location within the system. 
     Other non-limiting examples include applications that are not fully automated but where the advanced maneuverability provided by the omnidirectional steering and drive units allows human directed vehicles to operate more efficiently than existing steering and drive systems allow. Another application allows asymmetrical items which, for example, might be long and narrow, to be transported by omnidirectional AGVs or human guided vehicles down a travel lane that was wide enough to accommodate their length (for example), then shifted sideways following a different axis into narrower storage lanes and/or storage racks without having to allow for room for turning radii to turn the AGV or load within or in to the storage aisles. 
     Other non-limiting uses of an omnidirectional drive and steering unit include the movement of stage or set components in theatre performances or stage productions; platform movement in display or theatrical environments; hospital patient transport on carts or patient movement in medical scanners; movement or sorting of large items in manufacturing applications or use in factories; production machinery and materials handling and movement; bomb removal and suspicious package retrieval robots; people moving and transport mechanisms; product packaging, package handling and sorting systems; and Transfer Tables for moving and positioning large components in fabricating or manufacturing environments. 
     While the present invention has been described at some length and with some particularity with respect to the several described embodiments, it is not intended that it should be limited to any such particulars or embodiments or any particular embodiment, but it is to be construed with reference to the appended claims so as to provide the broadest possible interpretation of such claims in view of the prior art and, therefore, to effectively encompass the intended scope of the invention. Furthermore, the foregoing describes the invention in terms of embodiments foreseen by the inventor for which an enabling description was available, notwithstanding that insubstantial modifications of the invention, not presently foreseen, may nonetheless represent equivalents thereto.