Expandable mechanical structure for mobile living units

A recreational vehicle, comprising:

• a main body;
• a first side expansion structure operable to extend from a first side of the main body, the first side expansion structure increasing an interior living area within the mobile living unit;
• a rotational arm extension system for moving the first side expansion structure between a collapsed state and an expanded state;
• and
• a floor member of the first side expansion structure that is stored, in the collapsed state of the first side expansion structure, in an upright position generally orthogonal to a use position when the first side expansion structure is in the expanded state, wherein:
• side walls of the first side expansion structure fold to store along a direction of travel of the mobile living unit;
• the floor is a bifold floor having a main floor section and a secondary floor section, wherein the main floor section is configured to fold against the secondary floor section in the collapsed state, and the main floor section and the secondary floor section form a continuous floor surface when the first side expansion structure is in the expanded state;
• and
• the main floor section is configured to fold against the secondary floor section in the collapsed state, and the main floor section and the secondary floor section form a continuous floor surface when the first side expansion structure is in the expanded state.

A recreational vehicle, comprising:

• a main body;
• a first side expansion structure operable to extend from a first side of the main body, the first side expansion structure increasing an interior living area within the mobile living unit;
• a floor member of the first side expansion structure that is stored, in the collapsed state of the first side expansion structure, in an upright position generally orthogonal to a use position when the first side expansion structure is in the expanded state;
• and
• a rotational arm extension system for moving the first side expansion structure between a collapsed state and an expanded state, wherein the rotational arm extension system includes:
• an extension motor unit driving rotation of an inner extension arm, the extension motor unit pivotably attached at a first end of the inner extension arm;
• a first end of an outer extension arm pivotably connected to a second end of the inner extension arm;
• and
• a second end of the outer extension arm pivotably connected to an outer connector, the outer connector attached to an outer wall of the first side extension structure, wherein:
• the rotational arm extension system includes a first rotational arm extension system at a first side of the first side expansion structure, and a second rotational arm extension system at a second side of the first side expansion structure;
• and
• side walls of the first side expansion structure fold to store along a direction of travel of the mobile living unit.