Driving apparatus maintaining ground contact of drive-wheel

A driving apparatus for maintaining a ground contact of a drive-wheel, comprising:

• a loading plate (140, 240) on which a loaded object is loaded;
• a first support (110, 210) connected to a lower portion of one side of the loading plate (140, 240);
• a second support (120, 220) connected to a lower portion of the other side of the loading plate (140, 240);
• a hinge (130, 230) configured to connect the first support (110, 210) to the second support (120, 220) in a hinge structure;
• at least a pair of drive-wheels (160, 260) coupled to both sides of a lower portion of the second support (120, 220);
• a driver configured to rotate and drive the drive-wheels (160, 260);
• a first connector configured to connect a front end portion of the loading plate (140, 240) to the first support (110, 210) to allow the loading plate (140,240) and the first support (110, 210) to be relatively pivoted;
• and
• a second connector configured to connect a rear end portion of the loading plate (140, 240) to the second support (120, 220) to allow the loading plate (140,240) and the second support (120, 220) to be relatively pivoted.