A mobile object comprising: a self-position detection unit configured to detect a self-position of the mobile object on a basis of first sensor information; a position change detection unit configured to detect a position change unpredictable in advance on a basis of a detection result by the self-position detection unit, wherein the position change detection unit detects a position change to a lifted state as the position change unpredictable in advance; a self-location estimation unit configured to estimate a self-location with a first estimation model on a basis of second sensor information, and estimate a self-location with a second estimation model different from the first estimation model in a case where a position change unpredictable in advance is detected by the position change detection unit; an action plan generation unit configured to generate an action plan on a basis of a peripheral situation of a self-location estimated by the self-location estimation unit; and a control unit configured to control an operation of the mobile object on a basis of an action plan determined by the action plan generation unit, characterized in that the self-location estimation unit includes: a time-series information accumulation unit that accumulates as time-series information sensed with the second sensor information; a time-series information self-location estimation unit configured to use time-series information accumulated in the time-series information accumulation unit to estimate the self-location, and output an estimation result as a time-series information self-location; and a current information self-location estimation unit configured to estimate the self-location on a basis of current information that is current information sensed with the second sensor information, and output as a current information self-location, and wherein the self-location estimation unit adopts the time-series information self-location as a self-location estimation result in a case where the position change unpredictable in advance is not detected, and adopts the current information self-location as a self-location estimation result in a case where the position change unpredictable in advance is detected. a self-position detection unit configured to detect a self-position of the mobile object on a basis of first sensor information; a position change detection unit configured to detect a position change unpredictable in advance on a basis of a detection result by the self-position detection unit, wherein the position change detection unit detects a position change to a lifted state as the position change unpredictable in advance; a self-location estimation unit configured to estimate a self-location with a first estimation model on a basis of second sensor information, and estimate a self-location with a second estimation model different from the first estimation model in a case where a position change unpredictable in advance is detected by the position change detection unit; an action plan generation unit configured to generate an action plan on a basis of a peripheral situation of a self-location estimated by the self-location estimation unit; and a control unit configured to control an operation of the mobile object on a basis of an action plan determined by the action plan generation unit, characterized in that the self-location estimation unit includes: a time-series information accumulation unit that accumulates as time-series information sensed with the second sensor information; a time-series information self-location estimation unit configured to use time-series information accumulated in the time-series information accumulation unit to estimate the self-location, and output an estimation result as a time-series information self-location; and a current information self-location estimation unit configured to estimate the self-location on a basis of current information that is current information sensed with the second sensor information, and output as a current information self-location, and a time-series information accumulation unit that accumulates as time-series information sensed with the second sensor information; a time-series information self-location estimation unit configured to use time-series information accumulated in the time-series information accumulation unit to estimate the self-location, and output an estimation result as a time-series information self-location; and a current information self-location estimation unit configured to estimate the self-location on a basis of current information that is current information sensed with the second sensor information, and output as a current information self-location, and wherein the self-location estimation unit adopts the time-series information self-location as a self-location estimation result in a case where the position change unpredictable in advance is not detected, and adopts the current information self-location as a self-location estimation result in a case where the position change unpredictable in advance is detected. adopts the time-series information self-location as a self-location estimation result in a case where the position change unpredictable in advance is not detected, and adopts the current information self-location as a self-location estimation result in a case where the position change unpredictable in advance is detected.