Patent Publication Number: US-7900867-B2

Title: Personal propulsion device

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a Divisional of U.S. Utility patent application Ser. No. 11/789,552, filed Apr. 25, 2007, by Raymond Li, entitled PERSONAL PROPULSION DEVICE, now allowed, which application is a Continuation of U.S. Utility patent application Ser. No. 11/088,330, filed Mar. 23, 2005, by Raymond Li, entitled PERSONAL PROPULSION DEVICE, now U.S. Pat. No. 7,258,301, issued Aug. 21, 2007, which application is related to and claims priority to U.S. Provisional Patent Application Ser. No. 60/556,396, filed Mar. 26, 2004, entitled PERSONAL PROPULSION DEVICE, which application is related to U.S. Provisional Patent Application Ser. No. 60/581,438, filed Jun. 22, 2004, entitled PERSONAL PROPULSION DEVICE, the entirety of which is incorporated herein by reference. 
    
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     n/a 
     FIELD OF THE INVENTION 
     The present invention relates to powered flight, more specifically, to a personal propulsion device. 
     BACKGROUND OF THE INVENTION 
     Personal flight has been an eternal dream and a recent reality. However, unlike birds, human beings have a low power-to-weight ratio, and personal flight has only been accomplished by developing machines using powerful engines and aerodynamic lifting surfaces, such as autogyro aircraft, fixed wing airplanes, and helicopters. Arguably, the closest experience to that of individual, unrestricted flight has been attained through the use of single passenger devices, consisting mainly of a flight pack or similar structure that fits on or around the torso of an individual. 
     Typically, flight packs include propulsion devices such as propellers, rotor blades, or rockets, which often require a highly flammable fuel in order to generate sufficient thrust for flight. In addition to having a reservoir of volatile fluid attached to the body of a pilot, the close proximity of the propeller, rotor blades, or rocket exhaust to the pilot further poses significant safety risks. Another drawback of such self-contained, single-passenger flight packs is that the pilot must support the entire weight of both the airframe and fuel on his back, which can be highly uncomfortable and places severe limits on operation duration and range. Moreover, the location of thrust forces and the weight distribution of the fuel and accompanying components in such designs increase instability during take-off and for the duration of the flight. 
     Existing single passenger devices suffer an additional major drawback, in that the fuselage, engine, electrical equipment, fuel, and flight instrumentation are all part of the aircraft. As a result of the added weight of these systems, a significant amount of engine output and fuel is required to generate sufficient thrust to achieve flight. This necessitates larger and heavier engines and, even then, the power-to-weight ratio is often quite low. 
     As an alternative to employing the combustion of volatile fluids to directly generate thrust, the high-pressurization of non-flammable fluids, such as water, has been proposed to create sufficient thrust in order to achieve flight. While the use of pressurized water may significantly reduce the above-mentioned safety risks, even water-propelled devices still have drawbacks in that the pressurization source must be carried into the air along with the fuselage and accompanying systems, contributing to a low power-to-weight ratio, and requiring larger engines in order to generate sufficient thrust. 
     It would be desirable to provide a single passenger aircraft that is safe, stable, and achieves a higher power-to-weight ratio than typical single-passenger devices. Moreover, it would be desirable to provide a single passenger aircraft that provides maneuverability, vertical takeoff and landing, as well as practical flight range and duration. 
     SUMMARY OF THE INVENTION 
     The present invention provides a personal propulsion device having a body unit, a base unit, and a delivery conduit in fluid communication with both the body unit and the base unit. The body unit may include a thrust assembly having at least two independently pivotable thrust nozzles, as well as a single linkage that accomplishes the pivoting movement. The nozzles are located above a center of gravity for the body unit, which provides inherent stability when the personal propulsion device is in use. The body unit may further include buoyant characteristics, as well as throttle controls and the like. 
     The base unit can include a wave-piercing hull that encloses an engine and a pump, which provides pressurized fluid to the delivery conduit. The delivery conduit subsequently delivers the pressurized fluid to the body unit, in order to provide sufficient thrust to lift the body unit and an operator into the air. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A more complete understanding of the present invention, and the attendant advantages and features thereof, will be more readily understood by reference to the following detailed description when considered in conjunction with the accompanying drawings wherein: 
         FIG. 1  illustrates a personal propulsion device in accordance with the present invention; 
         FIG. 2  is a rear view of a personal propulsion device in accordance with the present invention; 
         FIG. 3  is a top view of a personal propulsion device in accordance with the present invention; 
         FIG. 4  is a front view of a harness system of a personal propulsion device in accordance with the present invention; 
         FIG. 5  is a top view of a swivel housing of a personal propulsion device in accordance with the present invention; 
         FIG. 6  is a cross sectional view of the swivel housing at line A-A of  FIG. 5 ; 
         FIG. 7  is a cross sectional view of the swivel housing at line B-B of  FIG. 6 ; 
         FIG. 8  is a side view of a pump vessel in accordance with the present invention; 
         FIG. 9  is a side view of an engine control module in accordance with the present invention; 
         FIG. 10  is a cross sectional view of the cross arm with throttle twist grip at line C-C in  FIG. 9 ; 
         FIG. 11  is an illustration of a personal propulsion device in forward flight in accordance with the present invention; 
         FIG. 12  is an illustration of a personal propulsion device in hover flight in accordance with the present invention; 
         FIG. 13  is an illustration of a takeoff with forward translation of a personal propulsion device from shallow water in accordance with the present invention; 
         FIG. 14  is an illustration of a vertical takeoff of a personal propulsion device in accordance with the present invention; 
         FIG. 15  is an illustration of a method using a personal propulsion device in accordance with the present invention; 
         FIG. 16  shows a pond or pool-based embodiment of a personal propulsion device in accordance with the present invention; and 
         FIG. 17  depicts an alternative use of a personal propulsion device in accordance with the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Now referring to  FIGS. 1 through 4 , an exemplary embodiment of the present invention provides a personal propulsion device  10  having a body unit  12 , a base unit  14  capable of providing pressurized fluid flow, and a delivery conduit  16  in fluid communication with both the body unit  12  and the base unit  14 . 
     The body unit  12  includes a body harness system  18  having a torso corset  20 , a seat post  22  and a saddle  24 . The torso corset  20  may have a modified barrel shape, contoured to provide firm support, protection and comfort for the torso, while further transmitting the lifting and gravity forces to an operator. While the torso corset  20  is preferably made of a generally rigid material such as fiberglass-reinforced plastic, the torso corset  20  may include flexible extension flaps  26  that wrap around the waist of an operator. An extension flap cushioning  27  may be attached to the extension flaps  26 , thereby providing a band of foam-like material that cushions and supports the weight of the body unit  12  and the body harness system  18  on the hip bone of an operator. The body harness system  18  can further include a waist strap  28 , shoulder straps  30 , groin straps  32 , and a chest strap  34  to hold an operator in place. Furthermore, a corset extension  36  provides protection for the rear regions of the operator&#39;s head and neck. The torso corset  20  and harness system  18  provide rigidity to the body unit  12  for improved stability, provide protection and comfort to the operator, and distribute a substantial amount of the operator&#39;s bodyweight over a wide area including the torso, groin and buttocks areas. In addition to promoting stability, the torso corset  20  and the accompanying straps and cushioning can be made from a buoyant material sufficient to keep the body unit  12  and an operator of at least 200 pounds afloat in a body of water for a prolonged period of time. 
     The seat post  22  and the saddle  24  of the body unit  12  support part of the weight of the operator and, in addition to the rigidity provided by the harness system  18 , further reduce unnecessary movements and oscillations of the lower torso of an operator which can destabilize the body unit  12  during flight. The weight of the operator is distributed over the saddle  24 , the groin straps  32 , as well as over the contact surfaces with the torso corset  20  and the body harness system  18 . 
     As shown in  FIGS. 1-3 , the body unit  12  has a thrust assembly having a supply conduit assembly  38 , left swivel housing  40 , right swivel housing  42 , left thrust nozzle  44 , and right thrust nozzle  46 . Each swivel housing is affixed to or is integral with an upper support arm  48  and a pair of lower support arms  50 ,  50 ′, with both the upper and lower support arms being affixed to the torso corset  20  in order to transmit lift and propulsion forces. The supply conduit assembly  38  further includes a medially located and vertically disposed main conduit  52  that rises from about mid-back level and branches into a left bifurcation conduit  54  and a right bifurcation conduit  56 . Both bifurcated conduits course upward and forward to terminate in flanges  58 , which are pivotally mounted inside both the left swivel housing  40  and the right swivel housing  42 . The bifurcated conduits are preferably made from 3.00″ outside diameter rigid tubing, while the main conduit  52  is preferably made from 4″ outside diameter rigid tubing, with the upper end formed to join smoothly with the bifurcated conduits. 
     The left thrust nozzle  44  and right thrust nozzle  46  are pivotally attached to the swivel housings  40 ,  42  with flanges  60  matching the bifurcated conduits&#39; flanges  58 . As shown in  FIGS. 5 through 7 , multiple washers  62  made of a low-friction material, and a strip  64  around the perimeter of the flanges, reduce friction between the flanges&#39; contact surfaces inside each swivel housing. An O-ring  66  seated in a groove between the flanges further provides a seal against fluid leaks. The flanges  58 ,  60  and washers  62  are housed inside both swivel housings  40 ,  42 . The swivel housings  40 ,  42  each further include a front housing element  68  and a rear housing element  70 . The swivel housings provide the ability of both the thrust nozzles as well as the main conduit to pivot about a centerline axis “CA” extending through the swivel housings. 
     Now referring to  FIG. 3 , the body unit  12  further includes a port side control arm assembly  72  and a starboard side control arm assembly  74 , both of which are attached to thrust nozzles  44  and  46  respectively. A cross arm  76  connects the control arm assemblies  72 ,  74  at their outer ends. Control arm assemblies  72 ,  74  each include a cross arm collar  78 , which is affixed to an outer control arm  80 . The outer control arm  80  is further connected to a mid control arm  82 , with an extension spring  84  attached to their inner walls. The mid control arm  82  is connected to an inner control arm  86  with an adjustable telescoping mechanism, and the inner control arm  86  is attached to the front surface of the thrust nozzles  44  and  46 . By moving the cross arm  76  in an up-and-down direction, the operator can deflect both control arm assemblies  72 ,  74  together, which in turn deflect the thrust nozzles  44 ,  46  together to vary the allocation between lift and propulsion force vectors. The flexible articulation at the extension spring  84  allows the operator to deflect port and starboard thrust nozzles  44 ,  46  by different amounts, thus generating yaw control moments. Moreover, this flexibility provides independent control of either nozzle through a single common linkage, i.e., the cross arm  76 . Roll control is not often required in a wingless flight device, but the operator can affect roll control by shifting weight from side-to-side within the body harness system  18 . The static and dynamic friction of the thrust nozzles&#39; swivel mechanism are intended to maintain any set deflection position, in order to allow hands-free hovering and to prevent accidental loss of control should the operator release his grip on the cross arm  76 . 
     Now referring to  FIGS. 9 and 10 , the body unit  12  can include a twist grip control that allows throttle control to be integrated with the cross arm  76 . The twist grip control includes a twist grip  88  extends across a substantial length of the cross arm  76 , in order to allow the pilot to operate the twist grip control with either one or both hands. A crank  90  is affixed to the end of the twist grip  88  by a clamp  92 , and is further pivotally connected to a throttle control master cylinder piston  94 . To facilitate free deflection of the twist grip  88 , a plastic sleeve  96  can be included to reduce the friction between the twist grip and the inner core of the cross arm  76 . 
     Referring now to  FIGS. 3 and 9 , a control housing  98  can be affixed to the outer control arm  80  with an angled bracket  100 . When the twist grip  88  is rotated by the operator, it deflects the crank  90 , which pushes or pulls the throttle control master cylinder piston  94  in a master cylinder (not shown) inside the control housing  98 . The master cylinder movements are transmitted by hydraulic pressure along hydraulic tubing  104  to an engine compartment in the base unit  14 , where it actuates a dual-action throttle actuator piston to move the throttle crank on an engine. As a result, actuation of the twist grip  88  on the body unit  12  is communicated to the base unit  14 , which can result in subsequent modification of the fluid flow provided by the base unit  14 . The throttle control mechanism is intended to maintain any set position in order to maintain flight dynamics should the operator release his grip on the cross arm  76 . The control housing  98  can also include a start/stop electric control  106  and an engine overheat warning buzzer  108 , both of which communicate with the base unit  14  through a multi-lead electric cable  110 . Where necessary, additional gauges or monitors for navigation purposes and for monitoring base unit performance may also be located in the control housing  98 . The hydraulic tubing  104  and multi-lead electric cable  110  may be integrated with the delivery conduit  16  in order to achieve communication with the base unit  14 . 
     The thrust assembly of the body unit  12  provides lightweight, simple, reliable and stable control for the personal propulsion device  10 . When dry, the body unit  12  exerts little weight on the pilot. Moreover, simple mechanical devices provide the pilot with thrust mechanisms as well as pitch, roll and yaw controls. No engine, transmission, or propeller-type devices are located on the body unit  12 , the absence of which provides simplicity as well as reliability and safety in the operation of the personal propulsion device  10 . 
     The body unit  12  includes a center of gravity “CG” when in use, where, in an exemplary embodiment of the present invention, the dual thrust nozzles  44  and  46  generate nozzle reaction forces for lift and propulsion at a point well above the center of gravity “CG.” By positioning the nozzles above the center of gravity “CG,” a significant portion of the forces acting on the body unit, i.e., lift, propulsion, steering, gravity, tension in the delivery conduit, etc., converge normally to the centerline axis “CA” about which the thrust nozzles  44  and  46  and the supply conduit assembly  38  deflect, thereby isolating a substantial amount of the destabilizing forces and moments from the operator. Moreover, as an operator in body unit  12  ascends to greater heights, the weight of fluid moving through the delivery conduit provides greater stability as the weight of the entrained fluid further offsets any destabilizing forces or movements that an operator may experience. 
     In an exemplary embodiment, as shown in  FIG. 8 , the base unit  14  includes a hull  112 , a water-tight deck  114  and a snorkel mast  116  for engine air and ventilation. The engine  118  is located towards the aft portion of the base unit  14 , and powers a drive shaft  120  that rotates an impeller  122  in a pump  124 . The engine  118  inducts air through an air passage in the snorkel mast  116 , and exhaust gases pass through a noise reduction muffler  126  and subsequently exit through an exhaust port  128  located in the stern. 
     When the engine  118  is in operation, water is inducted through a water intake  130 , past stationary guide vanes  132  that divert the water flow forward through a pump intake channel  134  into the pump  124 , where the impeller  122  transfers energy to the water to increase its speed and pressure. Pressurized water exits through a bow discharge conduit  136 , where the pressurized water flow proceeds into the delivery conduit  16 . The delivery conduit  16  provides the pressurized water flow to the main conduit  52  of the body unit  12 , where the flow is routed to the left and right thrust nozzles  44  and  46 . The engine  118  preferably generates sufficient pressurization of the water exiting the bow discharge conduit  136  such that the fluid mass flow rate at the left and right nozzles of the body unit  12  generate sufficient thrust to lift approximately 200 pounds or more a height of 30 feet for a sustained period of time. 
     The base unit  14  is intended to be adaptable for a wide variety of applications, and may include variations in form. For example, the base unit  14  may have a wave-piercing hull in order to minimize the possibility of becoming airborne due to large waves. Such activity could interrupt water intake in the base unit  14 , resulting in lost thrust in the body unit  12  and the potential for rapid descent of an operator. A wave-piercing hull would ensure that rather than elevating above a large wave, the base unit  14  would pierce or pass through a portion of a wave, thereby remaining in contact with the water and preventing any interruption of fluid flow to the body unit  12 . 
     The delivery conduit  16  is preferably a large diameter hose, i.e., four inches or more, having a lightweight polyester jacket and extruded polyurethane lining. This construction provides sufficient tensile strength for towing the base unit  14 , as well as low internal friction, kink resistance, abrasion and chemical resistance, ultraviolet light resistance, high burst strength, and minimal stretching or warping under pressure. In addition to minimizing friction with the pressurized water flow, the delivery conduit also provides additional weight with the entrained water such that flight stability is increased when the personal propulsion device is in operation. Moreover, hydraulic control tubing and control cables may be housed in a flexible protective rubber sheath affixed along a surface of the delivery conduit  16 . 
     By separating the fuselage, engine, pump, electrical system, cooling system, lubrication system, and fuel system of a typical aircraft and instead supporting these systems independently in the base unit  14  on land or water, a very large percentage of the potential weight of the body unit  12  is eliminated. Instead, power is delivered to the body unit  12  through the delivery conduit  16 , which carries water from the base unit  14  to the body unit  12 . This arrangement allows a relatively small engine to generate sufficient lift and propulsion for the body unit  12 , and enables the personal propulsion device  10  to operate with much higher efficiency, more maneuverability, and longer range and flight duration. 
     Potential applications for the personal propulsion device  10  include a recreational and rescue vehicle, a ship-based mobile vessel system for duties at sea; a land-based fixed system for amusement rides, demonstrations and training; and a stealth mobile vessel system optimized for low-detection underwater travel for law enforcement and military applications. 
     Referring now to  FIGS. 11 and 12 , an exemplary embodiment includes using the personal propulsion device  10  over water, wherein the base unit  14  is mobile and is towed along by the thrust generated at the body unit  12 . During flight, a section  138  of the delivery conduit  16  is suspended in the air by the lift from the body unit  12 . The remaining portion  140  of the delivery conduit  16  between the suspended section and the base unit  14  floats near the surface of the water through natural buoyancy and hydrodynamic lift. In forward flight, the suspended section  138  of the delivery conduit  16  is slanted due to tension between the forward thrust of the body unit  12  and water resistance on the hull  112  of the base unit  14 . In hover mode, gravity pulls down on the suspended section  138  of the delivery conduit  16  so that it is almost vertical. The weight of entrained water pulls a section  140  of the hose under water, and provides hover stability to the body unit  12  by offsetting a constant airborne mass against a constant lift from nozzle reaction forces. 
       FIG. 13  illustrates a takeoff of the body unit  12  with forward translation. Shallow water may be preferred for performing most takeoffs and landings, although takeoffs from deep water, shores, dock structures or from aboard another vessel are equally possible. Upon deploying the base unit  14  on the water and starting the engine  118 , the operator increases the throttle and as lift is felt, he trims the thrust nozzle angles to provide maximum lift and minimal forward propulsion. After takeoff, the pilot continues to increase throttle and at the same time deflect the thrust nozzles rearwards to initiate forward flight. Forward thrust may also be enhanced kinesthetically by pitching the upper torso forward. When in forward flight, the base unit  14  is passively propelled by tension originating from the body unit  12  through the delivery conduit  16  and is slowed down rapidly from water resistance as tension in the delivery conduit  16  is reduced or changes direction. Although not illustrated, alternative embodiments may incorporate active propulsion for the base unit  14  in both forward and reverse directions, in response to flight control commands initiated by the operator on the body unit  12 . 
     Now referring to  FIG. 14 , in order to hover with the personal propulsion device  10 , the operator increases the throttle and at the same time trims the thrust nozzle angles for maximum lift and neutral horizontal propulsion, and continues increasing the throttle until the desired altitude has been reached. 
     As shown in  FIG. 15 , the personal propulsion device may be used as a ship-based means for transporting personnel or cargo from one ship to another. In such an embodiment, a large multi-purpose pump on a supply or rescue vessel  142  supplies the power for lift and propulsion through the delivery conduit  16 , which may have an increased diameter for this particular application, to the body unit  12  as previously described. Repair and maintenance work can be performed on the vessel, and human and cargo payloads can be transferred between the supply ship  142  and another vessel  144 , even in relatively rough sea conditions where other methods of transfer may be too dangerous. 
     Now referring to  FIG. 16 , an alternative embodiment of use for the personal propulsion device  10  providing a land-based application. In this alternative embodiment, a pond or pool  146  provides a safe and restricted access area for operation. A powerful pump preferably located in a pump house  148  draws in water from near the surface of the pond or pool through a skimmer  150  and a supply duct  152  (shown in this embodiment as buried underground). The water is then pumped through a conduit  154  (also shown in this embodiment as buried underground) to a base  156  at the bottom of the center of the pond or pool  146 , then subsequently through a hose  158  to the body unit  12 . In this particular embodiment, the water flow at the thrust nozzles may be controlled by a flow regulating device located in a main conduit of the body unit  12 . An exterior enclosure  160  may be included to restrict the flight area, and a submerged safety net  162  can provide a safe base for takeoffs and landings. This pond or pool-based embodiment can be installed anywhere with access to a water supply, and hence can be deployed in high traffic amusement parks, next to major traffic arterials, and in gathering areas where a natural body of water is not available. This embodiment is especially useful for marketing, demonstrations, training, pilot certification, and as a paid admission amusement ride. 
     In yet another embodiment of the present invention an operator can use the personal propulsion device  10  for travel in both air and water. As shown in  FIG. 17 , an alternative embodiment of the present invention provides for low-detection travel under water. Assisted by an underwater breathing apparatus or snorkel equipment, the operator can travel underwater for long distances with water jet propulsion from a ballasted base unit  164 . A snorkel mast  166  is fitted with ports and passages for engine air intake and exhaust, and a floatation chamber  168  operates to keep the snorkel ports above the waterline when the base unit  164  is under tow. Camouflage material  170  such as an artificial waterfowl or floating debris may be affixed to the snorkel tower  166  to disguise the tower and the wakes generated when traveling. This embodiment may be favorably employed in military and law enforcement applications where both stealth and airborne mobility are important for approaching floating or near shore targets. 
     It will be appreciated by persons skilled in the art that the present invention is not limited to what has been particularly shown and described herein above. In addition, unless mention was made above to the contrary, it should be noted that all of the accompanying drawings are not to scale. A variety of modifications and variations are possible in light of the above teachings without departing from the scope and spirit of the invention, which is limited only by the following claims.