Balance exercise machine

A balance exercise machine comprising:

• a seat on which a trainee sits;
• a swing mechanism that swings the seat with a swing motion in an anteroposterior direction and a swing motion in a widthwise direction;
• a controller that controls the swing mechanism, wherein
• moving speed in the swing motion of the seat in the anteroposterior direction is twice as fast than that in the widthwise direction;
• and
• origin of the swing motion of the seat in the widthwise direction is set from a position discrepant within a quarter-cycle or a half-cycle from origin of the swing motion of the seat in the anteroposterior direction to a position coinciding with the origin of the swing motion of the seat in the anteroposterior direction;
• an extendable and contractible mechanism that varies a distance between the seat and the swing mechanism by extension or contraction thereof so as to vary a stroke of a swing motion of the seat, wherein
• said controller further controls the extendable and contractible mechanism;
• a supporting unit that supports the swing mechanism rotatably around a predetermined rotation axis;
• a pedestal that is to be established on a floor and supports the supporting unit rotatably around a first horizontal axis, and wherein
• the extendable and contractible mechanism comprises:
• a first inclination mechanism that is provided between the pedestal and the supporting unit, and varies an inclination angle of the rotation axis of the swing mechanism in a vertical plane;
• and
• a second inclination mechanism that is provided between the swing mechanism and the seat, and varies an inclination angle of the seat around a rotation axis of the seat.