Patent ID: 7708093

Claim:
A motorized wheelchair with stand-up capability comprising: front drive wheels comprising a plurality of independently controllable drive wheels, each having an axle centerline in the vicinity of the arches of a user's feet; drive motors to power said plurality of independently controllable drive wheels; one or more caster mounted rear wheels; a seat and a backrest; a lift mechanism to lift and lower said seat and said backrest; said lift mechanism comprising lift frames that transition said seat and said backrest from a seated position wherein said lift mechanism is oriented along an essentially horizontal axis of said motorized wheelchair to a standing up position wherein said lift mechanism is in an essentially collapsed parallelogram configuration oriented along an essentially vertical axis of said motorized wheelchair; a telescoping cylinder connected to said seat such that a lifting force pushes said seat from an essentially horizontal position to an essentially vertical position that causes the transition of said lift mechanism from the essentially horizontal axis to the essentially vertical axis of said motorized wheel chair and transitions said lifting mechanism from the essentially horizontal orientation to said essentially collapsed parallelogram orientation; at least one onboard energy source to power said drive motors and said lift mechanism; a leg brace system to hold the user's legs in straight extended position, such that said leg brace system provides support to the user's legs when in standing position, said leg brace system comprising at least one proximal shaft and at least one distal shaft, said at least one proximal shaft and said at least one distal shaft meeting end to end at an interface of essentially forty-five degrees; an axle connecting said at least one proximal shaft and said at least one distal shaft at said interface, said axle penetrating the interface at an angle essentially normal to the interface, such that rotation of said at least one proximal shaft and said at least one distal shaft relative to one another causes said at least one proximal shaft and said at least one distal shaft to transition between relative angles of essentially zero degrees for an open configuration, to essentially ninety degrees for a closed position; a brace pad attached to the other end of said at least one distal shaft, such that when said at least one distal shaft is in a retracted position, said brace pad occupies a point interior to the essentially ninety degree angle formed by said at least one proximal shaft and said at least one distal shaft; and a means for adjustably mounting said leg brace system to said motorized wheelchair.