referring initially to fig1 a , illustrated is a left front isometric view of one embodiment of a personal mobility device 100 ( e . g ., convertible personal mobility device ) constructed according to the principles of the present invention . the personal mobility device 100 comprises an open frame having a left side structure 110 ; a left intermediate vertical support 111 ; a right side structure 120 ; a right intermediate vertical support 121 , a front structure 130 ; a rear structure 140 ; left and right main mobility wheels 151 , 152 , respectively ; first through fourth auxiliary wheels 153 - 156 ; a knee rest 160 ; a seat 170 ; a front floor panel 181 ; and a rear floor panel 182 . the term “ mobility wheel ” as used herein is intended to include all wheels that an occupant can reasonably use to self - propel the mobility device and / or occupant . as shown in the embodiment of fig1 a , the left and right main mobility wheels 151 , 152 , respectively , are positioned such that the occupant may propel the vehicle himself with his hands . for example , the left and right main mobility wheels 151 , 152 , respectively , may have hand rails 151 a , 152 a as in conventional wheel chairs . the first through fourth auxiliary wheels 153 - 156 provide anti - tip stability to the mobility device 100 . for the purposes of this discussion , the occupant of the personal mobility device 100 will be referred to as the “ occupant ” and , left and right are the occupant &# 39 ; s left and right as seated , kneeling or standing within the device . referring now to fig1 b , illustrated is a left front partially disassembled , isometric view of the personal mobility device 100 of fig1 a folded for transport or storage . fig1 b illustrates the ease with which the personal mobility device 100 can be folded for storage or vehicle transportation . the left side structure 110 further comprises : a left front vertical support 112 , a left upper rail 113 , a left rear vertical support 114 and a left lower rail 115 . the right side structure 120 further comprises : a right front vertical support 122 , a right upper rail 123 , a right rear vertical support 124 and a right lower rail 125 . front floor panel 181 is shown detached from the left lower rail 115 and folded into substantial alignment with the right side structure 120 . the knee rest 160 is shown detached from the left front vertical support 112 and also folded into substantial alignment with the right side structure 120 . rear floor panel 182 is shown detached from the right bottom rail 125 and folded into substantial alignment with the left side structure 110 . the seat 170 is shown detached from the right front vertical support 122 and also folded into substantial alignment with the left side structure 110 . an optional upper torso support 190 and an optional body sling 195 are also shown and may each be rendered substantially planar for storage or vehicle transportation . referring now to fig2 , illustrated is a left side elevation view of a second configuration of the personal mobility device 100 of fig1 a configured as a wheelchair 200 . in this configuration , the front and rear floor panels 181 , 182 , respectively , are coupled to the left and right lower rails 115 , 125 , respectively , ( 125 not visible ). the seat 170 comprises an outer seat structure 272 and an inner seat structure 273 slidably coupled within the outer seat structure 272 . the outer seat structure 272 is rotatably coupled to the left and right rear vertical supports 114 , 124 , respectively , ( 124 not visible ). the inner seat structure 273 is rotatably coupled to the left and right intermediate vertical supports 111 , 121 , respectively , ( 121 not visible ). a first plurality of attach points 201 a - 201 n on the left rear vertical support 114 provide a variety of points at which to attach one end 271 of the outer seat structure 272 . a second plurality of attach points 202 a - 202 n on the left intermediate vertical support 111 provide a variety of points at which to attach an end 274 of the inner seat structure 273 . ( see fig3 ) the inner seat structure 273 is slidably coupled within the outer seat structure 272 to accommodate a variety of lengths that may be necessary as the seat 170 is positioned at a desirable height and angle for the occupant . the seat 170 may be rotatably coupled to the vertical supports in a variety of ways well known in the art , e . g ., a spring - loaded barrel bolt into an aperture on the vertical supports . a third plurality of attach points 203 a - 203 n on the left front vertical support 112 are also provided . their function will be discussed below . the left and right main mobility wheels 151 , 152 , respectively , may have left and right hand rails 151 a , 152 a for manual propulsion of the device 200 . the left and right main mobility wheels 151 , 152 may be available in different diameters to accommodate the reach of the occupant . the left and right main mobility wheels 151 , 152 may also be vertically coupled at different attach points 202 a - 202 n to compensate for the larger or smaller wheel diameter so long as the left and right bottom rails 115 , 125 do not contact the surface on which the wheels roll . the device 200 may further comprise motors 210 a interposed the main mobility wheels 151 , 152 and their respective vertical supports 111 , 121 . alternatively , the motors 210 b may be friction drive motors configured to contact an outer surface of the main mobility wheels 151 , 152 . a battery ( not shown ) may be positioned in any convenient location , e . g ., on the rear floor panel 182 . motor controls may be located on or near the upper rails 113 , 123 and wires routed through the structural tubing which makes up the frame . power assist wheels ™ are additionally available as replacements for standard wheels , and are operated through a battery pack at the wheel axis . referring now to fig3 , illustrated is a left side elevation view of a third configuration of the personal mobility device 100 of fig1 a configured as an occupant - propelled kneeling vehicle 300 . in this configuration , the front and rear floor panels 181 , 182 , respectively , are coupled to the left and right bottom rails 115 , 125 , respectively , ( 125 not visible ) as in fig2 . however , the rear floor panel 182 has a foot rest 381 rotatably coupled thereto and upwardly inclined therefrom . the foot rest 381 may be rotatably coupled and supported by any convenient methods , e . g ., spring - loaded barrel bolt into the rear floor panel 182 frame for pivot , and rotatable support leg 382 folding down from the foot rest 381 to engage a recess in the rear floor panel 182 . the outer seat structure 272 has been moved vertically on the left and right rear vertical supports 114 , 124 ( 124 not visible ). the inner seat structure 273 is rotatably coupled to the left and right intermediate vertical supports 111 , 121 , respectively , ( 121 not visible ) as before , but at a higher location . the inner seat structure 273 is slidably coupled within the outer seat structure 272 to accommodate a variety of lengths that are necessary as the seat 170 is positioned at a desirable height and angle for the occupant &# 39 ; s kneeling position . the knee rest 160 comprises an outer knee rest structure 361 and an inner knee rest structure 362 . the outer knee rest structure 361 rotatably couples to the left and right front vertical supports 112 , 122 ( 122 not visible ). the inner knee rest structure 362 rotatably couples to the left and right intermediate vertical supports 111 , 121 ( 121 not visible ). the seat 170 and knee rest 160 are adjusted for the comfort of the occupant . thus , as an occupant - propelled mobility device , the occupant may operate the main mobility wheels 151 , 152 with his / her hands . referring now to fig4 a , illustrated is a left side elevation view of a fourth configuration of the personal mobility device 100 of fig1 a configured as a self - propelled walker 400 . in this configuration 400 , the knee rest 160 and the seat 170 are rotated to substantially - vertical positions within the front and rear structures 130 , 140 , respectively . referring now to fig4 b , illustrated is a left front isometric view of the self - propelled walker 400 of fig4 a . the front and rear floor panels 181 , 182 , respectively , are rotated to substantially - vertical positions within the right and left side structures 120 , 110 , respectively . referring now to fig5 a , illustrated is a left side elevation view of a fifth configuration of the personal mobility device 100 of fig1 a configured as an attendant - propelled or occupant - propelled standing mobility device 500 . in this configuration 500 , the knee rest 160 and the seat 170 are rotated to substantially - vertical positions within the front and rear structures 130 , 140 , respectively . the front and rear floor panels 181 , 182 , respectively , are rotated to substantially - horizontal positions and each is coupled to both the right and left bottom rails 125 , 115 , respectively ( 125 not visible ). with the occupant standing on the front and rear floor panels 181 , 182 , respectively , the attendant may propel the standing mobility device 500 with handles 501 . however , as the main mobility wheels 551 , 552 ( 552 not visible ) may be changed for an appropriate size and vertical attach point whereby the occupant can access the hand rails 551 a , 552 a ( 552 a not visible ), the occupant may self - propel the standing mobility device 500 . referring now to fig5 b , illustrated is a left front isometric view of a sixth configuration of the personal mobility device 100 of fig1 a configured as an attendant - propelled standing mobility device 510 . in this configuration 510 , the occupant is assisted in standing with the optional upper torso support 190 and optional body sling 195 . operation of this configuration is the same as the configuration 500 of fig5 a . with support surrounding the user &# 39 ; s midsection and two large attached wheels , the device allows for a more stabilized , safer and potentially faster gait than standard walkers . referring now to fig5 c , illustrated is a right rear isometric view of the configuration of the personal mobility device 510 of fig5 b . this figure illustrates how the occupant will access the interior of the personal mobility device 510 . the seat 170 , a portion 520 of the upper torso support 190 , and a portion 530 of the rear structure 140 have been rotated to permit access to the personal mobility device 510 . one who is of skill in the art will readily understand how the body sling 195 ( see fig5 b ) would be attached to the torso support 190 . the access principles illustrated here are also applicable to the configurations 300 , 400 and 500 . referring now to fig6 a , illustrated is a left front isometric view of a second embodiment of a personal mobility device 600 constructed according to the principles of the present invention . the personal mobility device 600 comprises an open frame having a left side structure 610 ; a left intermediate vertical support 611 ; a right side structure 620 ; a right intermediate vertical support 621 ; a front structure 630 ; a rear structure 640 ; left and right main mobility wheels 651 ; 652 , respectively ; left and right auxiliary wheels 653 - 654 ; optional left and right motors 655 , 656 ; a knee rest 660 ; a seat 670 ; a floor panel 681 ; a foot rest 683 ; and a waist support band 690 . note that this embodiment will function in a manner similar to the first embodiment configuration 300 of fig3 . that is , the seat 670 is rotatably coupled to the rear structure 640 and the left and right intermediate vertical supports 611 , 621 . the knee rest 660 is rotatably coupled to the front structure 630 and the left and right intermediate vertical supports 611 , 621 . alternatively , the knee rest 660 and seat 670 may be rotatably coupled to their respective supports by means of a ratchet mechanism , e . g ., such as are found on folding ladders . the waist support band 690 may be adjustable for size through the use of hook and loop fasteners . the occupant may be assisted by an attendant pushing on the left and right side structures 610 , 620 or the occupant may self - propel the mobility device 600 . referring now to fig6 b , illustrated is a left front partially - exploded , isometric view of the personal mobility device 600 of fig6 a . note that the floor panel 681 folds into the right side structure 620 and the knee rest 660 and seat 670 detach from the left and right side structures 610 , 620 . referring now to fig6 c , illustrated is a left side elevation view of the personal mobility device 600 of fig6 a . the advantage of this embodiment is that it uses fewer parts and only four wheels . by attaching the seat 670 to the vertical support 640 which also is the attach point for the hub 657 of the main mobility wheel 651 , the center of gravity of the device and occupant always remains between the left and right auxiliary wheels 653 - 654 and the main mobility wheels 651 , 652 . those skilled in the art understand that while the embodiments described above each include a knee rest , a seat , and a floor panel , embodiments may exist wherein any one or more of those elements may be omitted and yet remain within the purview of the disclosure . moreover , those skilled in the art to which this application relates will appreciate that other and further additions , deletions , substitutions and modifications may be made to the described embodiments , such as , but not limited to levered arms to replace attach point connections or track wheels to replace spring - loaded angle foot rests .
provided is a personal mobility device comprising a frame including two side structures . in one embodiment , main mobility wheels are coupled to ones of the side structures , the main mobility wheels configured to contact a surface upon which the mobility device is designed to move . in this embodiment , the mobility device further includes a knee rest rotatably coupleable to the frame , the knee rest being adjustable from a first substantially - vertical position to a second angled position , and further wherein the main mobility wheels are configured such that a kneeling occupant may propel the personal mobility device using the main mobility wheels .