Abstract:
An aerocar includes a body and a multiple of wings. The multiple of wings can be selectively extendable away from a top portion of the body for a flight mode. The multiple of wings can be selectively retractable toward the top portion of the body for a roadable mode.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This is a continuation of U.S. patent application Ser. No. 14/194,795, filed Mar. 2, 2014, which is hereby incorporated by reference in its entirety. 
    
    
     BACKGROUND 
     The present disclosure pertains to a vehicle that can be flown as a fixed wing aircraft and driven as a land vehicle. More specifically, the present disclosure is directed to stackable wing architectures therefor. 
     Flying has always been a dream central to the history of humanity. Aerocars or roadable aircraft are defined as vehicles that may be driven on roads as well as take off, fly, and land as aircraft. Vehicles that demonstrate such capability provide operators with freedom, comfort, and the ability to arrive quickly to a destination as mobility becomes three-dimensional yet remains private and personal. Such vehicles, however, may require various trade offs to facilitate operations in the flight mode and the roadable mode. 
     Typically, a body of a land vehicle is relatively short to facilitate parking and road maneuverability, whereas a body of an aircraft is relatively long to facilitate flight stability and control authority. In one conventional roadable aircraft, each wing folds upward at a root and downward a mid-span location to stow against the fuselage in the land mode. Although effective, the more numerous the fold locations, the greater the weight and complexity that necessarily influences operability in each mode. Further, such wing stowage may limit operator aft and side views conducive to effective operations in the road mode. 
     SUMMARY 
     In one respect, the subject matter described herein is directed to an aerocar. The aerocar can include a body and a multiple of wings. The multiple of wings can be selectively extendable away from a top portion of the body for a flight mode. The multiple of wings can be selectively retractable toward the top portion of the body for a roadable mode. 
     In another respect, the subject matter described herein is directed to an aerocar. The aerocar can include a body and a multiple of stackable wings. The multiple of stackable wings can be configured such that one or more of the stackable wings is selectively extended away from a top portion of the body for a flight mode. The multiple of stackable wings can be configured such that one or more of the stackable wings is selectively retracted toward the top portion of the body for the roadable mode. The wings can be selectively morphable between a stowed shape for the roadable mode and a deployed shape for the flight mode. 
     In still another respect, the subject matter described herein is directed to a method of configuring an aerocar. The aerocar has a flight mode and a roadable mode. The aerocar can include a body and a multiple of wings. The method can include selectively extending at least one of the multiple of wings away from a top portion of the body for the flight mode. The method can include selectively retracting the at least one of the multiple of wings toward the top portion of the body for the roadable mode. 
     The foregoing features and elements may be combined in various combinations without exclusivity, unless expressly indicated otherwise. These features and elements as well as the operation thereof will become more apparent in light of the following description and the accompanying drawings. It should be understood, however, the following description and drawings are intended to be exemplary in nature and non-limiting. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Various features will become apparent to those skilled in the art from the following detailed description of the disclosed non-limiting embodiment. The drawings that accompany the detailed description can be briefly described as follows: 
         FIG. 1  is a schematic view of an example aerocar with a stackable wing in a roadable mode retracted toward the body according to one disclosed non-limiting embodiment; 
         FIG. 2  is a schematic view of the aerocar of  FIG. 1  in a first flight mode with all of the stackable wings extended relative to the body; 
         FIG. 3  is a schematic view of the aerocar of  FIG. 1  in a second flight mode with less than all of the stackable wings extended relative to the body; 
         FIG. 4  is a schematic view of one stackable wing in the second flight mode of  FIG. 3 ; 
         FIG. 5  is a schematic sectional view of the wing of  FIG. 4  morphed to a stowed shape; 
         FIG. 6  is a schematic sectional view of the wing of  FIG. 4  morphed to a deployed shape; 
         FIG. 7  is a schematic view of an example aerocar with a stackable wing in a roadable mode retracted toward the body according to another disclosed non-limiting embodiment in which each wing is morphable between a stowed and a deployed shape; 
         FIG. 8  is a schematic view of the aerocar of  FIG. 7  in a first flight mode with all of the stackable wings extended relative to the body; and 
         FIG. 9  is a schematic view of the aerocar of  FIG. 7  in a second flight mode with less than all the stackable wing extended relative to the body. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  schematically illustrates an aerocar  10  in a roadable mode. The aerocar  10  generally includes a body  12  with a multiple of wheels  14 , of which at least one is a steerable wheel  14 A and at least one is a drive wheel  14 B, a power system  16 , a propulsor system  18  and a stackable wing system  20 . It should be appreciated that although particular systems and subsystems are separately defined, each or any of the subsystems may be combined or segregated. 
     The body  12  provides seating for the operator, passengers and cargo. The power system  16  operates to selectively power the drive wheel  14 B in the roadable mode as well as the propulsor system  18  such as a pusher propeller, open rotor, turbofan, or other thrust generation system in a flight mode. It should be appreciated that the roadable mode can include various front wheel, rear wheel and all wheel drive configurations. The power system  16  may be of various forms to include, but not be limited to, internal combustion engines, gas turbines, distributed electric propulsion systems or other energy conversion devices and combinations thereof. 
     The stackable wing system  20  selectively extends and retracts with respect to the body  12  and is that which provides a variable amount of lift for specific flight operations such as takeoff, landing ( FIG. 2 ), and cruise ( FIG. 3 ) operations. It should be appreciated that various other systems and subsystems such as a deployable empennage with horizontal and/or vertical stabilizers and various flight control surfaces such as a canards, elevators, rudders, ailerons, flaps, slats, flaperons, etc., are contemplated but not shown for the sake of clarity and to focus upon the stackable wing system  20 . 
     The stackable wing system  20  is located generally atop or at least partially within the body  12  to maintain the aerocar  10  within contained width dimensions to facilitate road operations. That is, each wing  22  of the stackable wing system  20  defines a span generally equivalent to a width of the body  12  to minimize the width of the aerocar  10  when in the roadable mode. The stackable wing system  20  facilitates, for example, parking of the aerocar  10  within typical home garages, parking spots, etc. 
     Each of the multiple of wings  22  selectively extend individually from the body  12  such that the stackable wing system  20  may be tailored for various flight operations. For example, all of the multiple of wings  22  are closely stacked atop or at least partially within the body  12  for the roadable mode; all of the multiple of wings  22  are extended from the body  12  for takeoff and landing operations to provide maximum effective wing area ( FIG. 2 ); and less than all of the multiple of wings  22  are extended from the body  12  to adjust the effective wing area for efficient cruise operations ( FIG. 3 ). It should be appreciated that the illustrated operational modes are schematic and merely examples in that various other arrangements and intermediate positions will also benefit herefrom. Furthermore, the inter-wing displacement between each of the multiple of wings  22  may alternatively or additionally be individually configured and controlled to optimize flight operations, stability and maneuverability. 
     With reference to  FIG. 4 , each of the multiple of wings  22  has a leading edge  30  and a trailing edge  32 , the space between which defines the chord. An upper surface  34  and a lower surface  36  that extend between the leading edge  30  and the trailing edge  32  define the desired airfoil shape. The upper surface  34  may also be generally referred to as the suction side and the lower surface  36  as the pressure side. It should be appreciated that various types of airfoils, e.g., flat bottom, symmetric, non-symmetric, under chamber, and other airfoils may be provided. 
     In one disclosed non-limiting embodiment, the upper surface  34  forms a rigid shell of a generally fixed shape that may be manufactured of, for example, a prepreg composite material such as woven fiberglass material embedded in a suitable resin matrix, a metal alloy such as aluminum, and combinations thereof. That is, the upper surface  34  is manufactured as a generally rigid and fixed cross-sectional profile. 
     The lower surface  36 , in contrast to the upper surface  34 , is morphable. That is, the lower surface  36  has a variable cross-sectional profile that can morph between a stowed shape  36 A ( FIG. 5 ) and a deployed shape  36 B ( FIG. 6 ). It should be appreciated that the stowed shape  36 A and the deployed shape  36 B may be of various cross-sectional profiles and the cross-sectional profiles depicted are merely schematic. 
     In this disclosed, non-limiting embodiment, the stowed shape  36 A generally follows the shape of the upper surface  34  such that the multiple of wings  22  may nest when stowed for the roadable mode ( FIG. 7 ). This nestable, stackable wing  22  in this disclosed non-limiting embodiment can thereby morph from the stowed shape  36 A ( FIG. 5 ) to the deployed shape  36 B ( FIG. 6 ) as each associated wing  22  is selectively extended away from the body  12  to the desired deployed flight mode ( FIGS. 8 and 9 ). That is, the morphable lower surface  36  facilitates a compact, closely stowable architecture with respect to the vehicle body  12  but morphs to the deployed shape  36 B ( FIG. 6 ) for the flight mode. Such a closely stowable architecture facilitates, for example, a low profile and stylish body design potential when in the roadable mode that also does not interfere with the side and aft view for the driver. 
     In this disclosed, non-limiting embodiment, the deployed shape  36 B of the lower surface  36  extends generally away from the upper surface  34  to form the airfoil shape. In other words, the stowed shape  36 A forms a compact shape of reduced thickness while the deployed shape  36 B forms the airfoil shape. That is, the lower surface  36  curves toward the upper surface  34  in the stowed shape  36 A and the lower surface  36  curves away from the upper surface  34  in the deployed shape  36 B. 
     The lower surface  36  may be manufactured of a bistable morphing material such as a bistable composite operable to snap from one stable shape into another, e.g., between the stowed shape  36 A ( FIG. 5 ) and the deployed shape  36 B ( FIG. 6 ). Bistable composites are a type of composite structure that have two statically stable modes. This bi-stability property results from locked, in-plane residual stresses and may be particularly appropriate to an adaptive structure such as the lower surface  36  as continued power is not required to hold each stable mode. The change between stable states is physically realized as a jump phenomenon or snap-through, which is strongly non-linear in nature. 
     Bistable composites may include non-symmetric laminates, where there are multiple fiber directions within the lay-up such that a bistable curve is formed. Further, various thicknesses may also be provided in the lay-up of the lower surface  36  to control the shape of the curve and thus produce a desired airfoil profile. It should be appreciated that although a bistable morphing material is disclosed in the illustrated embodiment, tri-stable as well as other adaptive structures will benefit herefrom. 
     With continued references to  FIG. 4-6 , the lower surface  36  may be selectively morphed between the stowed shape  36 A and the deployed shape  36 B by an actuator  40 . The actuator  40  may, for example, include an electrical power source that applies an electric current to generate Joule heating within an electric heating material embedded within the morphing bi-stable laminate. The embedded electric heating material is operable to selectively elevate the temperature to effect movement between states. This morphing bi-stable laminate can thereby morph from one stable state to the other stable state by the heating effect. 
     In another example, the actuator  40  may be an air source that is operable to apply a pressure to “snap” the lower surface  36  to the deployed shape  36 B or a suction to “snap” the lower surface  36  to the stowed shape  36 A. It should be appreciated that various other actuators will benefit herefrom. 
     The actuator  40  may be operated in response to a control subsystem  42  that generally includes a control module  44  with a processor  46 , a memory  48 , and an interface  50 . The processor  46  may be any type of microprocessor having desired performance characteristics. The memory  48  may include any type of computer readable medium which stores the data and control algorithms described herein such as those that deploy and configure the wings  22  for the desired flight operations. 
     With reference to  FIGS. 5 and 6 , to facilitate maintaining the lower surface  36  in the deployed shape  36 B, one or more articulable spars  60  extends between the lower surface  36  and the upper surface  34 . The articulable spars  60  function as structural members within each wing  22  to react to the torsional, bending, shear, and other loads developed within the wing  22  during flight operations. As defined herein “articulable” includes but is not limited to folding, telescoping, bending, hinging, and other movement. In one disclosed non-limiting embodiment, bistable material may be utilized to facilitate movement and stable positions of the articulable spars  60  in both the stowed shape  36 A and the deployed shape  36 B. 
     It should be understood that relative positional terms such as “forward,” “aft,” “upper,” “lower,” “above,” “below,” and the like are with reference to the normal operational attitude of the vehicle and should not be considered otherwise limiting. 
     Although the different non-limiting embodiments have specific illustrated components, the embodiments of this invention are not limited to those particular combinations. It is possible to use some of the components or features from any of the non-limiting embodiments in combination with features or components from any of the other non-limiting embodiments. 
     It should be understood that like reference numerals identify corresponding or similar elements throughout the several drawings. It should also be understood that although a particular component arrangement is disclosed in the illustrated embodiment, other arrangements will benefit herefrom. 
     Although particular step sequences are shown, described, and claimed, it should be understood that steps may be performed in any order, separated or combined unless otherwise indicated and will still benefit from the present disclosure. 
     The foregoing description is exemplary rather than defined by the limitations within. Various non-limiting embodiments are disclosed herein, however, one of ordinary skill in the art would recognize that various modifications and variations in light of the above teachings will fall within the scope of the appended claims. It is therefore to be understood that within the scope of the appended claims, the disclosure may be practiced other than as specifically described. For that reason the appended claims should be studied to determine true scope and content.