The excavator is a machinery used for all operations that require a ground movement, which means the removal of portions of soil or material extracted.

These machines can be of different types and have particular characteristics:

• wheeled, that is equipped with tires, which are useful for quickly movements but with limited load capacity;
• crawler, which are useful for movements on more complicated lands but consequently it will have a low speed of movement;
• mounted on pads, which are horizontal metallic structures in contact with the ground that can be handled by hydraulic pistons;
• with articulated supporting, this type of excavator is equipped with articulated brackets which allow more stability on inclined ground.