Patent Publication Number: US-2019175376-A1

Title: Self-Donning Powered Orthotic Device

Description:
RELATED APPLICATION 
     This application claims the benefit of U.S. Application No. 62/598,388, entitled “Self-Donning Powered Orthotic Device” and filed Dec. 13, 2017, which is hereby incorporated by reference in its entirety. 
    
    
     TECHNICAL FIELD 
     The present invention relates to a powered orthotic device, and more particularly to, a powered orthotic device configured to enable its wearer to don the device without assistance from another person. 
     BACKGROUND ART 
     Stroke, brain injury, and other neuromuscular trauma survivors are often left with hemiparesis, or severe weakness, in certain parts of the body. The result can be impaired or lost function in one or more limbs. It has been shown that people can rehabilitate significantly from many of the impairments following such neurological traumas by, for example, following a rehabilitative exercise regime that includes the execution of familiar and functional tasks. Many of these people may use powered orthotic devices to assist and/or enhance their abilities to perform these tasks. 
     The configuration of conventional powered orthotic devices typically requires wearers to rely on other people for assistance in donning the devices. For example, an orthotic device may include a set of sheaths to house the fingers of the wearer&#39;s hand. Since neurological trauma may cause the wearer&#39;s fingers to remain in a curled position, the wearer&#39;s fingers must be uncurled to be inserted into the sheaths. Because uncurling the fingers would occupy the wearer&#39;s free hand, the wearer would require another person to fit the sheaths over the straightened fingers. Since the wearer cannot don the orthotic device unless another person is available to help him or her don the device, the wearer performs rehabilitative exercise regimes less frequently and consequently exhibits slower progress towards neurological recovery. 
     SUMMARY OF THE EMBODIMENTS 
     In accordance with one embodiment of the invention, an improved powered orthotic device, of the type that is removably attachable to an arm of a wearer, includes a brace and a finger engagement member that is coupled to the brace and that engages a set of fingers. The powered orthotic device includes a thumb engagement member and a hand actuator configured to cause motion of the finger engagement member relative to the thumb engagement member. 
     The powered orthotic device includes a locking mechanism affixed to the brace, and a finger carrier assembly. The finger carrier assembly includes a finger carrier that is shaped to engage the set of fingers of the wearer when the finger carrier assembly is attached to the locking mechanism. The finger carrier assembly also includes an affixment member configured to be removably attached to the locking mechanism. The locking mechanism and the finger carrier assembly together constitute the finger engagement member. Moreover, the wearer can don the orthotic device, without assistance by a second person, by attaching the orthotic device to the arm of the wearer, placing the set of fingers into the finger carrier, and using a free hand of the wearer to affix the affixment member to the locking mechanism. 
     The affixment member may include a loop and the locking mechanism may include a catch that removably retains the loop. The catch may be spring-loaded in a latched position. The locking mechanism may also include a release configured to disengage the loop from the catch, and the release may be configured to slide between a latched position that retains the loop and an unlatched position that disengages the loop. The affixment member may include a dual side release buckle and the locking mechanism may include a catch that removably retains the dual side release buckle. The affixment member may removably attach to the locking mechanism via magnetic force. In some embodiments, the affixment member is configured to attach to the locking mechanism via friction fit. 
     The finger carrier may include a set of receivers such that the wearer places a different finger in each receiver. Each receiver may be a groove, a ring, a sleeve, or a cup. The finger carrier assembly may include a rigid stem disposed between the finger carrier and the affixment member. 
     In some embodiments, the finger carrier assembly includes a set of cables coupling the finger carrier to the affixment member and a tightening mechanism coupled to the cables. The tightening mechanism is configured to adjust tension in the cables, thereby enabling the cables to become tight for the wearer to don the orthotic device, and to become slack for the wearer to doff the orthotic device. 
     In various embodiments, the finger carrier includes a permanently attached grip that is configured to provide an increased surface area for contacting an object, relative to the finger carrier. The grip may include a rigid plate, and an underside of the grip may include a textured surface to increase friction between the grip and an object to be grasped. 
     The locking mechanism may be disposed on a portion of the brace configured to be coupled to a dorsal surface of the wearer&#39;s hand or a lateral surface of the wearer&#39;s hand. 
     In some embodiments, the wearer places the set of fingers into the finger carrier before using a free hand of the wearer to affix the affixment member to the locking mechanism. In other embodiments, the wearer uses a free hand of the wearer to affix the affixment member to the locking mechanism before placing the set of fingers into the finger carrier. 
     In accordance with another embodiment of the invention, an improved powered orthotic device, of the type that is removably attachable to an arm of a wearer, includes a brace and a finger engagement member, coupled to the brace, to engage a set of fingers. The powered orthotic device includes a thumb engagement member and a hand actuator configured to cause motion of the finger engagement member relative to the thumb engagement member. 
     The powered orthotic device includes an affixment member affixed to the brace and a finger carrier assembly. The finger carrier assembly includes a finger carrier shaped to engage the set of fingers of the wearer when the finger carrier assembly is attached to the affixment member. The finger carrier assembly also includes a locking mechanism configured to be removably attached to the affixment member. The affixment member and the finger carrier assembly together constitute the finger engagement member. The wearer can don the orthotic device, without assistance by a second person, by attaching the orthotic device to the arm of the wearer, placing the set of fingers into the finger carrier, and using a free hand of the wearer to affix the affixment member on the brace to the locking mechanism on the finger carrier assembly. The powered orthotic device includes any of the features described above, in any combination. 
     In accordance with another embodiment of the invention, a method of donning a powered orthotic device by a wearer without assistance by a second person includes attaching the orthotic device to an arm of the wearer. The orthotic device includes a brace, a finger engagement member, a thumb engagement member, and a hand actuator. The finger engagement member is coupled to the brace and configured to engage a set of fingers. The finger engagement member includes a locking mechanism and a finger carrier assembly, and the finger carrier assembly includes an affixment member and a finger carrier shaped to engage the set of fingers. The hand actuator is configured to cause motion of the finger engagement member relative to the thumb engagement member. 
     The method may include placing the set of fingers of a hand of the wearer in the finger carrier of the finger carrier assembly. The method may include removably attaching, using a free hand of the wearer, the affixment member to the locking mechanism. The method may include placing each finger in the set of fingers in a distinct receiver of a set of receivers of the finger carrier. Each receiver may be a ring. 
     The method may include retaining a loop of the affixment member on a catch of the locking mechanism. The affixment member may removably attach to the locking mechanism via magnetic force. The locking mechanism may be disposed on a portion of the brace configured to be coupled to a dorsal surface of the wearer&#39;s hand or a lateral surface of the wearer&#39;s hand. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The foregoing features of embodiments will be more readily understood by reference to the following detailed description, taken with reference to the accompanying drawings, in which: 
         FIGS. 1 and 2  are perspective views, from the right side and the left side respectively, of an exemplary powered orthotic device  101 , configured for use on the right arm, in accordance with an embodiment of the present invention; 
         FIG. 3  is a left side perspective view of an orthotic device  102  similar to that of  FIGS. 1 and 2 , but configured for use on the left arm, showing detail of the structure for coupling to a hand of a wearer (e.g., the hand assembly  31 ′), in accordance with an embodiment of the present invention; 
         FIG. 4  is a three-quarter (showing the front and right side) perspective view of the hand assembly  31 ′ of the powered orthotic device  102  of  FIG. 3  as donned on the hand of the wearer, but without the finger carrier assembly  150 ; 
         FIG. 5  is a three-quarter perspective view of a finger carrier assembly  150  for use with the hand assembly  31 ′ of  FIG. 4 , in accordance with an embodiment of the present invention; 
         FIG. 6  is a three-quarter perspective view of the hand assembly  31 ′ of the powered orthotic device  102  of  FIG. 3  as donned on the hand of the wearer, with the finger carrier assembly  150  engaged by the fingers of the hand, in accordance with an embodiment of the present invention; 
         FIG. 7  is a three-quarter perspective view of the hand assembly  31 ′ of  FIG. 6 , with the affixment member  160  of the finger carrier assembly  150  approaching the locking mechanism  170  that will maintain the fingers of the hand in a semi-straightened position, in accordance with an embodiment of the present invention; 
         FIG. 8  is a three-quarter perspective view of the hand assembly  31 ′ of  FIG. 6 , with the affixment member  160  of the finger carrier assembly  150  placed over the locking mechanism  170 , immediately before being latched to it, in accordance with an embodiment of the present invention; 
         FIG. 9  is a three-quarter perspective view of the hand assembly  31 ′ of  FIG. 6 , with the affixment member  160  of the finger carrier assembly  150  now latched to the locking mechanism  170 , in accordance with an embodiment of the present invention; 
         FIG. 10  is a side perspective view of the locking mechanism  170  of  FIGS. 1-4 and 6-9 , in accordance with an embodiment of the present invention; 
         FIG. 11  is a side perspective view of the locking mechanism  170  of  FIG. 10 , shown in relation to the approaching affixment member  160 , as in  FIG. 7 , in accordance with an embodiment of the present invention; 
         FIG. 12  is a side perspective view of the locking mechanism  170  of  FIG. 10 , shown with the affixment member  160  placed over the locking mechanism  170 , immediately before being latched to it, as in  FIG. 8 , in accordance with an embodiment of the present invention; 
         FIG. 13  is a side perspective view of the locking mechanism  170  of  FIG. 10 , shown with an affixment member  160  now latched to the locking mechanism  170 , as in  FIG. 9 , in accordance with an embodiment of the present invention; 
         FIGS. 14-16  are three-quarter perspective views (showing the front and right side, the bottom and right side, and the front and left side, respectively) of a finger carrier assembly  150 ′ with an integrated grip  1401 , in accordance with an embodiment of the present invention; 
         FIGS. 17-20  are three-quarter perspective views (showing the front and right side, the bottom and right side, the front and left side, and the bottom and left side, respectively) of the hand assembly  31 ″ of the powered orthotic device  102  of  FIG. 3 , but with the finger carrier assembly  150 ′ with the integrated grip  1401  of  FIG. 14 , as donned on the hand of the wearer, 
         FIG. 21  is a three-quarter (showing the front and right side) perspective view of an alternative embodiment of the hand assembly  31 ′″, as donned on the hand of the wearer, in which the hand support shell  118  includes the locking mechanism  170  and the remainder of the hand assembly  31 ′″ forms a hand unit  2101  with an affixment member  160  for mounting the hand unit  2101  to the hand support shell  118 ; 
         FIG. 22  is a three-quarter (showing the front and right side) perspective view of the hand support shell  118  used in the hand assembly  31 ′ of  FIG. 21 ; and 
         FIG. 23  is a three-quarter (showing the front and right side) perspective view of the hand unit  2101  used in the hand assembly  31 ′″ of  FIG. 21 . 
     
    
    
     DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS 
     Definitions 
     As used in this description and the accompanying claims, the following terms shall have the meanings indicated, unless the context otherwise requires: 
     A “set” includes at least one member. 
     An “orthotic device” is a device that supports weak or ineffective joints or muscles. An orthotic device is worn over existing body parts to support and/or restore function to a weakened or malformed body part. 
     A “finger engagement member”, which may be operated by the wearer without assistance from another person, is a structure that maneuvers the fingers of a wearer&#39;s impaired hand into a straightened position and couples the straightened fingers to a hand actuator on a powered orthotic device. 
     A “finger carrier” is a structural component, of a finger engagement member, that engages at least one finger of the wearer&#39;s hand. 
     A “locking mechanism” is a structure configured to secure a “finger carrier” to the powered orthotic device. 
     An “affixment member” is a structure configured to be removably attached to the “locking mechanism” to secure the “finger carrier” at the particular position on the powered orthotic device. 
     A “finger carrier assembly” is a structure that includes a “finger carrier” and one of the “affixment member” or “locking mechanism”. 
     Embodiments of the powered orthotic device include a finger engagement member that a wearer may apply to an impaired hand, using his or her other free hand. The configuration of the finger engagement member enables a wearer to don the powered orthotic device without assistance from another person. Since the wearer can don the powered orthotic device at will, the wearer can control the timing and frequency of his or her rehabilitative exercise regime, or perform tasks using the impaired hand when desired. As a result, the powered orthotic device grants the wearer a level of autonomy not provided by conventional orthotic devices. 
     Like conventional orthotic devices, the exemplary powered orthotic device is configured to enable the wearer to attach the orthotic device to a limb. For example, embodiments of the powered orthotic device may include straps, attached to a brace, which the wearer may wrap around parts of his or her body, such as an upper arm, a forearm, or both. The wearer may also insert his or her impaired hand into a hand support shell. 
     However, unlike the prior art, embodiments of the exemplary powered orthotic device include a finger engagement member that enables the wearer to uncurl the fingers of his or her impaired hand in tandem with engaging the fingers by the orthotic device. In some embodiments, the wearer engages the fingers of the impaired hand using a finger carrier assembly that may be removably attached to the powered orthotic device. When the finger carrier assembly is attached, the configuration of the finger engagement member maintains the fingers in a straightened position. 
     In further embodiments, the finger engagement member is irremovable from the orthotic device, and the wearer may manipulate the finger engagement member to engage the fingers of the impaired hand. For any of these embodiments, the wearer may operate the finger engagement member to release the fingers of the impaired hand, and subsequently doff the orthotic device. 
       FIGS. 1 and 2  are perspective views, from the right side and the left side respectively, of an exemplary powered orthotic device  101  configured for use on the right arm, in accordance with an embodiment of the present invention. The powered orthotic device  101  includes a brace  110  that supports an arm assembly  21  and a hand assembly  31 , which are structures for coupling the powered orthotic device  101  to an arm and a hand of the wearer, respectively. The arm actuator  113  of the arm assembly  21  is attached to one end of the brace  110  and includes a strap  112  configured to be wrapped and secured around an upper arm of the wearer. The arm assembly  21  includes another strap  114 , attached to a midsection of the brace  110 , configured to be wrapped and secured around a forearm of the wearer. Thus, the wearer may removably attach the powered orthotic device  101  to an arm by wrapping the straps  112 ,  114  around his or her upper arm and forearm, respectively. The arm actuator  113  is configured to cause motion of the brace  110  relative to the arm actuator  113 , thereby causing motion of the forearm relative to the upper arm. 
       FIG. 3  is a left side perspective view of an orthotic device  102  similar to that of  FIGS. 1 and 2 , but configured for use on the left arm, showing detail of the structure for coupling to a hand of a wearer (e.g., the hand assembly  31 ′), in accordance with an embodiment of the present invention. The hand assembly  31 ′ includes a cuff  116 , such as a multi-articulated wrist cuff, and a hand support shell  118 , both of which are attached to the brace  110 . In some embodiments, to couple the hand assembly  31 ′ to the wearer&#39;s hand, the wearer may first insert his or her wrist into the cuff  116  and guide the upper palm of the hand to rest upon the interior of the hand support shell  118 . The wearer may also insert the thumb of the impaired hand into a thumb engagement member  125  coupled to the brace  110 . Lastly, the wearer uses the finger engagement member  140  to couple the fingers of the impaired hand to the powered orthotic device  101 , particularly, the hand actuator  120 . 
     In the embodiments depicted in  FIGS. 1-3 , the finger engagement member  140  includes a finger carrier assembly  150  and a locking mechanism  170 . The locking mechanism  170  is mounted on a finger support platform  130  on the orthotic device  101 . The finger carrier assembly  150  includes a finger carrier  155 , which, in this embodiment, includes a set of receivers  156 . Each receiver  156  is configured to support a different finger of the wearer. The finger carrier  155  is coupled, via a stem  165 , to an affixment member  160 , and the affixment member  160  is configured to be removably attached to the locking mechanism  170 , which, in turn, is affixed to the powered orthotic device  101  or  102 . 
     A hand actuator  120  is attached to the brace  110 , and coupled to both the thumb engagement member  125  and the finger support platform  130 . When the wearer engages the fingers of the impaired hand with the finger carrier  155  and attaches the finger carrier assembly  150  to the locking mechanism  170 , the hand actuator  120  causes the finger engagement member  140  to move relative to the thumb engagement member  125 . Thus, when the wearer dons the powered orthotic device  101  or  102 , the powered orthotic device  101  or  102  moves the wearer&#39;s fingers relative to his or her thumb so that the wearer regains some of the grasping functionality in his or her hand lost due to the neurological trauma. 
       FIG. 4  is a three-quarter (showing the front and right side) perspective view of the hand assembly  31 ′ of the powered orthotic device  102  of  FIG. 3  as donned on the hand of the wearer, but without the finger carrier assembly  150 . In this figure, the wearer&#39;s thumb has been inserted in the thumb engagement member  125 , and the upper palm rests upon the hand support shell  118 . Due to neurological trauma, the fingers of the wearer may remain in a curled position. 
       FIG. 5  is a three-quarter perspective view of a finger carrier assembly  150  for use with the hand assembly  31 ′ of  FIG. 4 , in accordance with an embodiment of the present invention. 
       FIG. 6  is a three-quarter perspective view of the hand assembly  31 ′ of the powered orthotic device  102  of  FIG. 3  as donned on the hand of the wearer, with the finger carrier assembly  150  engaged by the fingers of the hand, in accordance with an embodiment of the present invention. To uncurl the fingers and couple the fingers to the powered orthotic device  101 , the wearer may operate a finger carrier assembly  150  configured for use with the hand assembly  31 ′. Grasping the finger carrier assembly  150  by the affixment member  160  (in this embodiment, a loop  160 ) or the stem  165 , the wearer may position each receiver  156  of the finger carrier  155  under a different finger of the impaired hand. 
       FIG. 7  is a three-quarter perspective view of the hand assembly  31 ′ of  FIG. 6 , with the affixment member  160  of the finger carrier assembly  150  approaching the locking mechanism  170  that will maintain the fingers of the hand in a semi-straightened position, in accordance with an embodiment of the present invention. As the wearer pulls the loop  160  or stem  165  towards the locking mechanism  170  on the finger support platform  130 , the finger carrier assembly  150  straightens the curled fingers of the hand. Because drawing the fingers into a straightened position may tax the energy of the wearer, the wearer may wish to rest in the midst of his or her efforts. In the embodiments shown in  FIGS. 1-4 and 6 , the locking mechanism  170  includes a hook  174  configured to receive the loop  160  of the finger carrier assembly  150 . When the loop  160  is suspended on the hook  174 , the finger carrier assembly  150  maintains the fingers in a semi-straightened position. As a result, the hook  174  and finger carrier assembly  150  preserve some of the repositioning achieved by the wearer, and the wearer may rest before completing the attachment of the finger carrier assembly  150  to the locking mechanism  170 . 
       FIG. 8  is a three-quarter perspective view of the hand assembly  31 ′ of  FIG. 6 , with the affixment member  160  of the finger carrier assembly  150  placed over the locking mechanism  170 , immediately before being latched to it, in accordance with an embodiment of the present invention, and  FIG. 9  is a three-quarter perspective view of the hand assembly  31 ′ of  FIG. 6 , with the affixment member  160  of the finger carrier assembly  150  now latched to the locking mechanism  170 , in accordance with an embodiment of the present invention. To attach the affixment member  160  of the finger carrier assembly  150  to the locking mechanism  170 , the wearer may pull the loop  160  over the base  175  of the locking mechanism  170 . When the loop  160  is positioned around the base  175 , the latch  172  secures the loop  160  and thus the attachment of the finger carrier assembly  150  to the locking mechanism  170 . 
       FIG. 10  is a side perspective view of the locking mechanism  170  of  FIGS. 1-4 and 6-9 , in accordance with an embodiment of the present invention. The locking mechanism  170  includes a latch  172  with a release  173 , and in this embodiment, the latch  172  is a spring-loaded catch. The spring (not shown) is disposed inside of the base  175  and maintains the catch  172  in a protruded position from the base  175 , i.e., a latched position. 
       FIG. 11  is a side perspective view of the locking mechanism  170  of  FIG. 10 , shown in relation to the approaching affixment member  160 , as in  FIG. 7 , in accordance with an embodiment of the present invention, and  FIG. 12  is a side perspective view of the locking mechanism  170  of  FIG. 10 , shown with the affixment member  160  placed over the locking mechanism  170 , immediately before being latched to it, as in  FIG. 8 , in accordance with an embodiment of the present invention. To attach the affixment member  160  to the locking mechanism  170 , the wearer pulls the loop  160  over the hook  174  and subsequently, the base  175 . As the wearer positions the loop  160  around the base  175 , the loop  160  pushes the catch  172  into the base  175 , sliding the catch  172  into the unlatched position. 
       FIG. 13  is a side perspective view of the locking mechanism  170  of  FIG. 10 , shown with an affixment member  160  now latched to the locking mechanism  170 , as in  FIG. 9 , in accordance with an embodiment of the present invention. After the wearer positions the loop  160  around the base  175  so as to lie flat on the finger support platform  130 , the loop  160  no longer contacts the catch  172 . The spring returns the catch  172  to the latched position and secures the finger carrier assembly  150  to the locking mechanism  170 . 
     Due to the angle of the stem  165  relative to the loop  160 , the finger carrier assembly  150  maintains the fingers of the impaired hand in a straightened position while the finger carrier assembly  150  remains attached to the locking mechanism  170 . Because the hand actuator  120  is coupled to the finger support platform  130  and the thumb engagement member  125 , the hand actuator  120  applies a force to cause motion of the finger engagement member  140  relative to the thumb engagement member  125 . The hand actuator  120  may determine the force based on sensor signals received from one or more sensors (not shown) coupled to a part of the wearer&#39;s body (e.g., upper arm, forearm, wrist, hand, finger) or attached to the brace  110 . Descriptions of the sensors that may be used by the orthotic device  101  may be found in U.S. application Ser. No. 15/183,279, entitled “Powered Orthotic Device and Method of Using Same” and filed Jun. 15, 2016, which is incorporated herein by reference in its entirety. 
     When the wearer is finished using the orthotic device  101 , the wearer may operate the release  173  of the locking mechanism  170  to remove the finger carrier assembly  150 . The wearer slides the release  173  to retract the catch  172  into the base  175  of the locking mechanism  170 . Because the catch  172  no longer retains the loop  160 , the wearer may lift the loop  160  over the base  175  to detach the finger carrier assembly  150 . The wearer may further remove the impaired fingers from the finger carrier  155 , and thereby allow his or her impaired hand to rest until the wearer next wishes to don the powered orthotic device  101 . 
     Alternate Embodiments of the Powered Orthotic Device  101   
     In the embodiments depicted in  FIGS. 1-4 and 6-9 , the locking mechanism  170  is disposed on the powered orthotic devices  101  and  102 , and the affixment member  160  is disposed on the finger carrier assembly  150 . However, the positions of the locking mechanism  170  and affixment member  160  may be reversed, i.e., the locking mechanism  170  may be disposed on the finger carrier assembly  150 , while the affixment member  160  is disposed on the orthotic device  101 ,  102 . Thus, in these embodiments, the wearer removably attaches the affixment member  160  on the brace  110  to the locking mechanism  170  on the finger carrier assembly  150 , to don the orthotic device  101 ,  102 . 
     The powered orthotic devices  101  and  102  may use other types of affixment members  160  and/or locking mechanisms  170  that mechanically attach to one another. For example, the affixment member  160  may include at least one flexible tang. The wearer may depress the tang to insert the affixment member  160  into the locking mechanism  170 , and when released, the tang may catch upon a ridge of the locking mechanism  170 . Depressing the tang releases the tang from the ridge, and the wearer may remove the affixment member  160 . One exemplary affixment member  160  with tangs is a dual side release buckle. In another example, the affixment member  160  is a buckle with a round tang, and the locking mechanism  170  includes a ring. The inner circumference of the ring matches the perimeter of the tang, and the wearer may depress the tang, insert the affixment member  160  into the locking mechanism  170 , and release the tang to catch upon the ring. In other embodiments, the affixment member  160  removably attaches to the locking mechanism  170  via friction fit. For example, the affixment member  160  may include a plug that fits into a socket of a locking mechanism  170 , although other types of male and female connectors may be used. 
     Alternative embodiments of the affixment members  160  and/or locking mechanisms  170  engage via magnetic force. Either the affixment member  160 , the locking mechanism  170 , or both may include ferromagnetic materials such as iron or nickel, or alloys thereof. To attach the finger carrier assembly  150  to the orthotic device  101  or  102 , the wearer places the affixment member  160  sufficiently close to the locking mechanism  170  for one component of the finger engagement member  140  to attract the other. The wearer removes the finger carrier assembly  150  by pulling the affixment member  160  with enough force to overcome the magnetic attractive force between the affixment member  160  and locking mechanism  170 . 
     Although the embodiments of  FIGS. 1-3 and 5-9  depict the set of receivers  156  of the finger carrier  155  as a saddle, other types of receivers  156  may be used to engage the fingers of the impaired hand. The set of receivers  156  may include a set of grooves, a set of rings, a set of sleeves, or a set of cups (e.g., a set of thimbles). In these other embodiments, each groove, ring, sleeve, or cup, respectively, is configured to engage a different finger of the impaired hand. However, other embodiments of the finger carrier  155  may include a single receiver  156  to engage the impaired fingers collectively. For example, the receiver  156  may be a bar configured to be positioned under all four fingers of the impaired hand. 
     Moreover, additional embodiments of the finger carrier assembly  150 ′ include a grip  1401  that improves the wearer&#39;s ability to grasp and/or control an object.  FIGS. 14-16  are three-quarter perspective views (showing the front and right side, the bottom and right side, and the front and left side, respectively) of a finger carrier assembly  150 ′ with an integrated grip  1401 , in accordance with an embodiment of the present invention. 
     In this embodiment, the grip  1401  is a semi-circular plate  1405  affixed to the finger carrier  155 . Compared to the receivers  156  of the finger carrier  155  alone, the flat surface  1410  on the underside of the plate  1405  provides an increased surface area for contacting an object. As a result, the grip  1401  enables the wearer to exert a larger amount of friction against the object, and consequently, superior control over the object. In this manner, the grip  1401  improves the security of any object within the wearer&#39;s grasp. Thus, when the wearer uses a finger carrier assembly  150 ′ with the grip  1401 , objects are less likely to slip from the wearer&#39;s hand as the wearer moves around or manipulates the objects. 
       FIGS. 17-20  are three-quarter perspective views (showing the front and right side, the bottom and right side, the front and left side, and the bottom and left side, respectively) of the hand assembly  31 ″ of the powered orthotic device  102  of  FIG. 3 , but with the finger carrier assembly  150 ′ with the integrated grip  1401  of  FIG. 14 , as donned on the hand of the wearer. As shown in these figures, the underside of the grip  1401  may match, or even extend beyond, the reach of the wearer&#39;s fingers, to improve the wearer&#39;s grasp of any object. 
     Although the embodiment of the grip  1401  depicted in  FIGS. 14-20  is a semi-circulate plate  1405 , other embodiments may assume alternative form factors. For example, the grip  1401  may be a plate that is circular, oval, or rectangular. In many embodiments, the plate  1405  may be rigid, whereas in other embodiments, the plate  1405  may be supple. The rigidity of any given plate  1405  may be tailored to the nature of the object to be grasped. 
     In various embodiments, the grip  1401  may have a curved surface, in lieu of the flat surface  1410 , and the wearer may match the curvature of the grip  1401  with the curvature of an object to be grasped. For example, suppose the wearer wishes to grasp a can. The wearer can select a finger carrier assembly  150 ′ whose integrated grip  1401  has a curved surface comparable to that of the can. After donning the powered orthotic device  102 , the wearer may position the grip  1401  against the can before tightening his or her grasp. Because the curved surface of the grip  1401  is configured for the object, the wearer can grasp the object more securely, compared to the receivers  156  depicted in  FIG. 5 . 
     Additionally, the flat surface  1410  may be textured to increase friction between the grip  1401  and an object. In some embodiments, the flat surface  1410  may include a grid of raised bumps. Alternatively, the flat surface  1410  may include a set of grooves. In another embodiment, the underside of the grip  1401  includes ridges arranged in a crosshatched pattern. 
     Furthermore, although the grip  1401  in the embodiment of  FIGS. 14-20  is integrated with the finger carrier assembly  150 ′, in other embodiments, the grip  1401  may be removably attachable to the receivers  156 . For example, the grip  1401  may include two clips, each configured to be removably attached to a separate receiver  156  of the finger carrier  155 . In another example, the grip  1401  may removably attach to the receivers  156  via magnetic force, via the ferromagnetic materials described above in relation to embodiments of the affixment members  160  and locking mechanisms  170 . The grip  1401  may include elastic loops, such that the wearer threads an end of each receiver  156  through a separate loop to secure the grip  1401  to the finger carrier  155 . Thus, for embodiments in which the grip  1401  is removably attachable to the finger carrier assembly  150 ′, the wearer may select a particular grip  1401  that would be most effective in grasping a desired object. 
     Furthermore, in lieu of a rigid stem  165 , the finger carrier assembly  150  may include a set of cables (not shown) coupling the finger carrier  155  to the affixment member  160 . The set of cables may be coupled to a tightening mechanism (not shown), and the wearer may operate the tightening mechanism to adjust the tension in the individual cables. In this embodiment, to don the powered orthotic device  101 , the wearer operates the tightening mechanism to loosen the cables. While the cables are slack, the wearer engages the fingers of the impaired hand with the finger carrier  155  and affixes the affixment member  160  to the locking mechanism  170 . The fingers remain curled due to the lack of tension in the cables. However, as the wearer tightens the cables, the tension pulls the fingers into a straightened position. In further embodiments, the set of cables and their associated tightening mechanism may be replaced with other flexible materials capable of maintaining the fingers in a straightened position, such as a set of elastic materials. 
     In various embodiments of the powered orthotic device  101 , the finger carrier assembly  150  may attach to the powered orthotic device  101  in different locations. The embodiments of  FIGS. 1-4 and 6-9  depict the locking mechanism  170  disposed on a portion of the brace  110  configured to be coupled to the dorsal surface of the wearer&#39;s impaired hand. However, the locking mechanism  170  may be disposed on a portion of the brace  110  configured to be coupled to a lateral surface of the wearer&#39;s hand, at the wrist cuff  116 , or any other location on the powered orthotic device  101 . In any of these embodiments, the stem  165  of the finger carrier assembly  150  is reconfigured to permit engagement of the wearer&#39;s fingers as demonstrated in  FIGS. 1-13 , regardless of the location of the locking mechanism  170 . 
     In alternate embodiments, the finger carrier assembly  150  is permanently affixed to the finger support platform  130 , instead of being removably attachable. The finger carrier assembly  150  is configured to be operated by the wearer to engage or disengage from the fingers of the impaired hand. For example, the finger carrier assembly  150  may include a bar linkage configured to slide between different positions. By extending the bar linkage, the wearer positions the bar linkage to support and/or straighten the fingers of the impaired hand. By retracting the bar linkage (e.g., towards the wearer&#39;s wrist), the bar linkage releases the fingers. The powered orthotic device  101 ,  102  may include a locking mechanism that, when engaged, prevents the bar linkage from sliding from its current position. Alternatively, the bar linkage is coupled to a hinge, and adjusting the hinge changes the position of the bar linkage relative to the fingers of the wearer&#39;s impaired hand. Other structures for supporting the fingers, such as a truss, as well as other mechanisms for changing the position of the permanently attached finger carrier assembly  150 , may be used. 
     In further embodiments, in which the finger carrier assembly  150  is permanently affixed to the finger support platform  130 , the hand assembly  31 ′″ is configured such that the hand support shell  118  includes the locking mechanism  170 , and the remainder of the hand assembly  31 ′″ forms a hand unit  2101  with an affixment member  160  for mounting the hand unit  2101  to the hand support shell  118 .  FIG. 21  is a three-quarter (showing the front and right side) perspective view of an alternative embodiment of the hand assembly  31 ′″, as donned on the hand of the wearer,  FIG. 22  is a three-quarter (showing the front and right side) perspective view of the hand support shell  118  used in the hand assembly  31 ′″ of  FIG. 21 , and  FIG. 23  is a three-quarter (showing the front and right side) perspective view of the hand unit  2101  used in the hand assembly  31 ′″ of  FIG. 21 . 
     To don the powered orthotic device  102 ′ of  FIGS. 21-23 , the wearer first guides the upper palm of the impaired hand to rest upon the interior of the hand support shell  118 . Then, the wearer may position each receiver  156  of the finger carrier  155  on the hand unit  2101  under a different finger of the impaired hand. As the wearer orients the hand unit  201  to pull its affixment member  160  over the locking mechanism  170  on the hand support shell  118 , the finger carrier assembly  150  straightens the curled fingers of the impaired hand. When the affixment member  160  is positioned around the base  175 , the latch  172  secures the affixment member  160  and thus the hand unit  2101  to the hand support shell  118 . The wearer may insert the thumb of the impaired hand into the thumb engagement member  125  coupled to the brace  110 . In this manner, the wearer may use his or her free hand to affix the hand unit  2101  to the hand support shell  118 , to form the hand assembly  31 ′″, and begin operating the powered orthotic device  102 . 
     When the wearer is finished using the powered orthotic device  102 , the wearer may operate the release  173  of the locking mechanism  170  to disengage the hand unit  2101  from the hand support shell  118 . The wearer slides the release  173  to retract the catch  172  into the base  175  of the locking mechanism  170 . Because the catch  172  no longer retains the affixment member  160 , the wearer may lift the affixment member  160  over the base  175  to detach the hand unit  2101 . The wearer may further remove the impaired fingers from the finger carrier  155 , and thereby allow his or her impaired hand to rest until the wearer next wishes to don the powered orthotic device  102 . 
     Although the embodiments shown in  FIGS. 21-23  depict the hand support shell  118  with the locking mechanism  170  and the hand unit  2101  with the affixment member, the positions of the locking mechanism  170  and affixment member  160  may be reversed, i.e., the locking mechanism  170  may be disposed on the hand unit  2101 , while the affixment member  160  is disposed on the hand support shell  118 . Moreover, the hand assembly  31 ′″ may use any other type of affixment member  160  and/or locking mechanism  170  described herein, or equivalents as would be appreciated by one of ordinary skill in the art. 
     Furthermore, in the embodiments of  FIGS. 21-23 , the locking mechanism  170  and affixment member  160  are disposed on portions of the hand support shell  118  and hand unit  2101 , respectively, to be coupled to a lateral surface of the wearer&#39;s hand. However, in other embodiments, the locking mechanism  170  and affixment member  160  may be disposed so as to be coupled to a dorsal surface of the wearer&#39;s hand. 
     The powered orthotic device  101  may also include actuators beyond the arm actuator  113  and hand actuator  120  depicted in  FIGS. 1-13 . The powered orthotic device  101  may include multiple actuators at any position where a single actuator has been depicted (e.g., multiple actuators coupled to the wearer&#39;s hand or elbow). Further actuators may be coupled to other joints of the wearer. Moreover, in some embodiments, one or more actuators may be located remotely from the joint(s) for which the actuators are aiding motion. 
     Various embodiments of the present invention may be characterized by the potential claims listed in the paragraphs following this paragraph (and before the actual claims provided at the end of this application). These potential claims form a part of the written description of this application. Accordingly, subject matter of the following potential claims may be presented as actual claims in later proceedings involving this application or any application claiming priority based on this application. Inclusion of such potential claims should not be construed to mean that the actual claims do not cover the subject matter of the potential claims. Thus, a decision to not present these potential claims in later proceedings should not be construed as a donation of the subject matter to the public. 
     Without limitation, potential subject matter that may be claimed (prefaced with the letter “P” so as to avoid confusion with the actual claims presented below) includes: 
     P1. An improved powered orthotic device of the type being removably attachable to an arm of a wearer, the device including a brace, a finger engagement member, coupled to the brace, to engage a set of fingers, a thumb engagement member, and a hand actuator configured to cause motion of the finger engagement member relative to the thumb engagement member, wherein the improvement comprises: 
     a finger carrier assembly affixed to the brace of the powered orthotic device, the finger carrier assembly including a finger carrier shaped to engage the set of fingers of the wearer, and 
     a control, configured to be operable by a wearer of the powered orthotic device, for moving the finger carrier assembly between a first position that engages the fingers of the wearer by the finger carrier and a second position that disengages the finger carrier from the fingers of the wearer, 
     so that the wearer can don the orthotic device, without assistance by a second person, by attaching the orthotic device to the arm of the wearer and using a free hand of the wearer to operate the control to move the finger carrier assembly to the first position to engage the fingers of the wearer. 
     The embodiments of the invention described above are intended to be merely exemplary; numerous variations and modifications will be apparent to those skilled in the art. All such variations and modifications are intended to be within the scope of the present invention as defined in any appended claims.