To conduct stable inversion control without using a special sensor or the like even if a projection such as a step or a fixed obstacle exists on a moving floor surface.

In this inversion type movable body including a rotor of which the section is circle, a drive part which rotates and drives the rotor, a movable body which holds the rotor, and a control part which controls the drive part and maintains the inversion state of the movable body by controlling the rotational drive of the rotor which is brought into contact with the floor surface, a measurement part which simultaneously obtains measurement values of four parameters such as a tilt angle to the vertical direction of the movable body, tilt angle velocity, a rotating angle of the rotor, and rotational angular velocity, and an estimation part which estimates one parameter value which is not selected based on the three selected parameter measurement values among the four parameter measurement values obtained by the measurement part and the control amount of the rotor are added. An abnormality of the inversion state of the movable body main body is detected based on a difference between the estimation value of the non-selected parameter and the measurement value.

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