excavators
Excavators are heavy construction equipment consisting of a boom, stick, bucket and cab on a rotating platform known as the "house".[1] The house sits atop an undercarriage with tracks or wheels. A cable-operated excavator uses winches and steel ropes to accomplish the movements.[2] They are a natural progression from the steam shovels and often called power shovels. All movement and functions of a hydraulic excavator are accomplished through the use of hydraulic fluid, with hydraulic cylinders and hydraulic motors.[3] Due to the linear actuation of hydraulic cylinders, their mode of operation is fundamentally different from cable-operated excavators.