Abstract:
A human exoskeleton includes a battery. The human exoskeleton also includes an electric motor electrically coupled to the battery and powered by the battery to actuate at least one component of the human exoskeleton in an activated state of the electric motor, the electric motor back-driven during a non-activated state of the electric motor to regenerate power in the battery.

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
       [0001]    This patent application claims priority to U.S. Provisional Patent Application Ser. No. 62/108,757, filed Jan. 28, 2015, which is incorporated herein by reference in its entirety. 
     
    
     BACKGROUND 
       [0002]    The embodiments described herein relate to human exoskeletons and, more particularly, to integrated power generation for human exoskeletons. 
         [0003]    Human assist exoskeletons are a relatively new reality. These exoskeletons are intended to provide assistance in numerous contemplated manners. For example, contemplated is assistance related to walking mobility or walking assist to paraplegics, persons with disability, persons recovering from surgery or the like. They require untethered power for long periods of time to provide unhindered all-day operation to promote widespread adoption of the technology. 
         [0004]    Many exoskeletons that are in development and/or production today have batteries integrated into their main electronic frame. This design requires a special external method to recharge the batteries. If the wearer is to continue using the device, the exoskeleton will be tethered to an electric power source until charging is completed. Such a situation lowers the usefulness of the technology and, ultimately, will greatly slow the adoption rate of the technology amongst potential users. 
         [0005]    Exoskeleton battery replacement is tedious and cumbersome, requiring removal of the exoskeleton in many cases and/or opening of a battery pack or the like to replace the battery that powers the exoskeleton, thereby undesirably hindering continuous and easy use. 
       SUMMARY OF THE INVENTION 
       [0006]    In one embodiment of the invention, a human exoskeleton includes a battery. The human exoskeleton also includes an electric motor electrically coupled to the battery and powered by the battery to actuate at least one component of the human exoskeleton in an activated state of the electric motor, the electric motor back-driven during a non-activated state of the electric motor to regenerate power in the battery. 
         [0007]    In another embodiment of the invention, a human exoskeleton includes a power supply electrically or chemically regenerated during a non-activated state of an actuation mechanism of the human exoskeleton. 
         [0008]    In yet another embodiment of the invention, a method of regenerating power for a human exoskeleton is provided. The method includes activating a battery of the human exoskeleton. The method also includes supplying power from the battery to an electric motor configured to actuate at least one component of the human exoskeleton in an activated state of the electric motor. The method further includes back-driving the electric motor during a non-activated state of the electric motor and during motion of the at least one component. The method yet further includes regenerating power in the battery while back-driving the electric motor in the non-activated state. 
         [0009]    These and other advantages and features will become more apparent from the following description taken in conjunction with the drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]    The subject matter which is regarded as the invention is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other features, and advantages of the invention are apparent from the following detailed description taken in conjunction with the accompanying drawings in which: 
           [0011]      FIG. 1  is a perspective view of a human exoskeleton; 
           [0012]      FIG. 2  illustrates the human exoskeleton worn by a user; and 
           [0013]      FIG. 3  illustrates a method of generating power for the human exoskeleton. 
       
    
    
     DETAILED DESCRIPTION 
       [0014]    Referring now to the Figures, where the invention will be described with reference to specific embodiments, without limiting same, an exoskeleton  10  is configured to be strapped around the waist of a user and is also strapped to the legs of a user. The exoskeleton  10  is adapted to assist a user in leg motion. In one embodiment, the exoskeleton  10  provides an “assist” mode that is only activated by the leg motion of a user. As such, the exoskeleton  10  provides additional “muscle” to a user, allowing better mobility to a user. While the illustrated and above-described embodiment pertain to an exoskeleton device that assists with leg motion of a user, it is contemplated that exoskeleton devices that assist with motion of other body parts, such as an arm, for example, will benefit from the embodiments disclosed herein. 
         [0015]    Referring to  FIGS. 1 and 2 , the exoskeleton  10  includes a frame  12  for fitting about the waist region of a user. In the illustrated embodiment, the frame  12  is substantially U-shaped, but alternative orientations are contemplated. The exoskeleton  10  also includes at least one leg extending from the frame  12 . In the illustrated embodiment, a first leg  14  and a second leg  16  are included. Each leg  14 ,  16  includes a coupling device  18 , such as a shackle, that connects the exoskeleton  10  to the user. The legs  14 ,  16  are moveable relative to the frame  12  to assist the user with mobility of the connected body parts (e.g., limbs). 
         [0016]    The exoskeleton  10  includes an actuating device that actuates movement of the leg(s). In some embodiments, a single actuating device  24  is included and is configured to drive each of the leg(s). In the illustrated embodiment, the actuating device comprises an electric motor in the form of a first electric motor  24  and a second electric motor  25 , the motors controlling each leg  14 ,  16 , respectively. A first gearbox  26  and a second gear box  27  are operatively coupled to the actuating device (e.g., electric motor) to achieve a desired movement of the legs,  14 ,  16 , in response to motion of an output of the actuating device, such as an output shaft of the electric motors  24 ,  25 . The electric motors  24 ,  25  and the gearboxes  26 ,  27  are operatively coupled to the frame  12  of the exoskeleton  10 . 
         [0017]    The electric motors  24 ,  25  are driven by at least one power supply operatively coupled to the frame  12 . In one embodiment, each electric motor  24 ,  25  is powered by a respective power supply, such as a first battery  34  and a second battery  36 . The batteries  34 ,  36  may be any type of battery, such as an electric battery or an electrochemical battery, for example. 
         [0018]    The embodiments described herein address issues with battery life that would otherwise limit a user&#39;s ability to embark on extended periods of use of the exoskeleton  10 . In one embodiment, the concept of power generation through the electric motors  24 ,  25  and gearbox sets  26 ,  27 . In particular, the exoskeleton  10  generates or uses electrical power interchangeably, as described in detail below. 
         [0019]    Referring now to  FIG. 3 , a method of controlling the exoskeleton  10  is illustrated and generally referenced with numeral  50 . The exoskeleton  10  is powered on  52  and gathers data  54  using batteries  34 ,  36 . A built-in microcontroller  42  ( FIG. 1 ) processes  56  this data and determines how to direct  58  the motors  24 ,  25  and possibly the gearboxes  26 ,  27 . If the motors  24 ,  25  are not activated  60  but the user is still moving, the motors  24 ,  25  will be back-driven  62 . The motion or lack of motion of the user in the body part of interest is detected due to the operative coupling of the coupling device  18  that connects the exoskeleton  10  to the user&#39;s body part (e.g., legs), as described above. When a user uses its&#39; own legs to move legs  14 ,  16 , electric motors  24 ,  25  will be back driven. In this scenario, the electric motors  24 ,  25  act as a generator and the generated electrical current is directed by the microcontroller  42  back into the batteries  34 ,  36  as a method of regenerating power  64 . This automatically recharges batteries  34  and  36  during movement of the user&#39;s legs, but without the assistance of the electric motors  24 ,  25 . 
         [0020]    The electrical and/or chemical power regeneration of the batteries  34 ,  36  in the manner described above is accomplished by eliminating an electrical hindrance that would impede the back-driving feature that enables power generation. Advantageously, power is provided to the exoskeleton  10  over an extended period of time due to the power generation capability described above. 
         [0021]    In another aspect of the embodiments disclosed herein, replacement of the batteries  34 ,  36  is employed to provide an extended period of time for the user to enjoy the beneficial assistance of the exoskeleton  10 . In such embodiments, the batteries  34 ,  36  are each coupled to the exoskeleton  10  at an exterior location such that disassembling the exoskeleton  10  is not required to access the battery mounting location. In the illustrated embodiment, the batteries  34 ,  36  are mounted to a rear portion of the exoskeleton  10 , however, alternative regions, such as side regions, upper regions or lower regions may be utilized as battery mounting locations. Furthermore, the batteries  34 ,  36  are not integrated with internal locations of the frame  12  and are not disposed within a pack or other casing that hinders the user&#39;s ability to easily access the battery for replacement. 
         [0022]    The battery may be coupled to the exterior mounting location of the exoskeleton  10  in any suitable manner that facilitates ease of removal for replacement with a replacement battery. For example, simple mechanical fasteners that are easily removed and installed with or without tools are contemplated. In this way, the connected batteries that are low or out of power are easily removed and are interchangeable with a plurality of replacement batteries while the exoskeleton remains on the user. In other words, at no time during replacement of the battery is the user required to take off the exoskeleton  10  to properly and easily conduct the replacement tasks. This allows a user to carry one or more replacement batteries in the event that the currently coupled battery runs out of its power supply. 
         [0023]    While the invention has been described in detail in connection with only a limited number of embodiments, it should be readily understood that the invention is not limited to such disclosed embodiments. Rather, the invention can be modified to incorporate any number of variations, alterations, substitutions or equivalent arrangements not heretofore described, but which are commensurate with the spirit and scope of the invention. Additionally, while various embodiments of the invention have been described, it is to be understood that aspects of the invention may include only some of the described embodiments. Accordingly, the invention is not to be seen as limited by the foregoing description.