Robot apparatus and controlling method thereof

A robot apparatus comprising:

• a main body;
• a display;
• a neck structure rotatably connected to the main body, and of which an end portion is connected to a rear surface of the display;
• a first driving device configured to rotate the neck structure around a first axis of the robot apparatus such that the display is positioned in a first location, in which a display surface of the display faces toward an upper direction, or a second location, in which the display surface faces toward a front direction;
• a stopper structure provided on the main body to be adjacent to the neck structure;
• and
• a second driving device configured to move the stopper structure toward the front direction or a rear direction such that the stopper structure is positioned in a supporting location in which the stopper structure contacts a rear surface of the neck structure, or a separated location, in which the stopper structure is spaced apart from the neck structure.