Rocking type exercising apparatus

1. A rocking type exercising apparatus comprising:

a movable unit on which a user rides; and

a driving unit for causing the movable unit to perform a rocking motion,

wherein the driving unit includes a pitch driving part for causing the movable unit to rock in a forward/backward direction, a roll driving part for causing the movable unit to rock in a leftward/rightward direction and a yaw driving part for causing the movable unit to rotate about a vertical axis, wherein, when the movable unit is moved forward by the pitch driving part and is tilted to either the left or the right by the roll driving part, the yaw driving part rotates the movable unit in the same direction as the tilted direction of the movable unit,

wherein a center point of the movable unit displaces downward while moving forward and displaces upward while moving backward, and

wherein two cycles of a forward/backward rocking motion are performed during one cycle of a leftward/rightward rocking motion.

2. The rocking type exercising apparatus of claim 1 , wherein the roll driving part of the driving unit causes the movable unit to make the leftward/rightward rocking motion by rotating the movable unit about a forward/backward axis inclined with respect to the movable unit and wherein a yawing motion about the vertical axis is added to the movement of the movable unit by making the distance between the forward/backward axis and a front end of the movable unit different from the distance between the forward/backward axis and a rear end of the movable unit.

3. The rocking type exercising apparatus of claim 2 , wherein the forward/backward axis has such an inclination that a front end of the axis lies lower than a rear end of the axis and wherein the distance between the forward/backward axis and the front end of the movable unit is greater than the distance between the forward/backward axis and the rear end of the movable unit.

4. The rocking type exercising apparatus of claim 2 , wherein the pitch driving part and the roll driving part are driven together by a rotational output of a single motor.

5. The rocking type exercising apparatus of claim 3 , wherein the pitch driving part and the roll driving part are driven together by a rotational output of a single motor.

6. The rocking type exercising apparatus of claim 2 , wherein the pitch driving part causes the front end of the movable unit to swing in the forward/backward direction and an upward/downward direction, and causes the rear end of the movable unit to swing in the forward/backward direction.

7. The rocking type exercising apparatus of claim 3 , wherein the pitch driving part causes the front end of the movable unit to swing in the forward/backward direction and an upward/downward direction, and causes the rear end of the movable unit to swing in the forward/backward direction.

8. The rocking type exercising apparatus of claim 4 , wherein the pitch driving part causes the front end of the movable unit to swing in the forward/backward direction and an upward/downward direction, and causes the rear end of the movable unit to swing in the forward/backward direction.

9. The rocking type exercising apparatus of claim 5 , wherein the pitch driving part causes the front end of the movable unit to swing in the forward/backward direction and an upward/downward direction, and causes the rear end of the movable unit to swing in the forward/backward direction.

10. The rocking type exercising apparatus of claim 1 , wherein a movement of the center point in the forward/backward direction is along a path in the forward direction that is displaced from a path of the center point in the backward direction.

11. The rocking type exercising apparatus of claim 1 , wherein the center point of the movable unit moves along a closed loop path.