Driving module of autonomous mobile robot

A driving module of an autonomous mobile robot, the driving module comprising:

• a first wheel in constant contact with a ground or a road surface and having a first rotational axis;
• a second wheel having a second rotational axis;
• a third wheel having a third rotational axis;
• and
• a control unit that controls a driving operation of the autonomous mobile robot, wherein:
• the second and third wheels are constrained to each other so as to be able to swing integrally about an intermediate axis portion positioned separately from the second and third rotational axes,
• the driving module further comprises a suspension unit connected to the second wheel or the third wheel and having a variable damping force, and
• whether or not the second wheel and the third wheel are in contact with the ground or the road surface is adjusted according to a swinging motion, and the damping force of the suspension unit is varied accordingly, and
• wherein the control unit controls a swinging motion of the second wheel and the third wheel about a swing drive axis based on a comparison a height of a step placed on the ground or the road surface and a radius of the third wheel or a swinging motion radius;
• and
• wherein the control unit controls such that:
• i) in a general driving, or when a height of a step placed on the ground or the road surface is less than the radius of the third wheel, the driving is performed while both the second wheel and the third wheel are in contact with the ground or the road surface;
• ii) when the height of the step placed on the ground or the road surface is greater than the radius of the third wheel and less than the swinging motion radius, a climbing step is performed while the second wheel remains in a contacted state with the ground or the road surface and the third wheel is lifted from the ground or the road surface and maintained in a non-contacted state;
• and
• iii) when the height of the step on the ground or the road surface is greater than the swinging motion radius, a signal is generated, indicating that it is impossible to climb the step.