The excavator, hailed as the ‘King of Construction Machinery’, plays an irreplaceable and crucial role in various construction projects, undertaking 60% – 75% of the workload. Its presence is active in numerous fields such as industrial and civil construction, transportation, pipelines, water conservancy and power, farmland transformation, mining, and modern military, serving as an important driving force for national economic construction.​

The origin of modern excavators can be traced back to the late 15th century in Italy. At that time, to meet the needs of dredging waterways for waterborne shipping, a type of silt dredging vessel emerged. According to “The Notebooks of Leonardo da Vinci”, this vessel consisted of two parallel small boats. A waterwheel – like rotating wheel was installed between the side – hulls. At the ends of the wooden poles at the four corners of the rotating wheel were buckets. The rotation of the wheel was driven by human power, enabling the buckets to reach the bottom of the river to scoop up silt. The bucket capacity was approximately 0.2 – 0.3m³. When the bucket filled with silt rotated to the top, it would be dumped into the cabin through a sliding board. This was the prototype of the excavator.​

From 1833 to 1835, William Otis, a railroad engineer in Philadelphia, USA, designed and manufactured the first steam – powered, jib – type single – bucket excavator installed on a railroad flatcar. Although it had a mixed iron – wood structure and the rotation of the jib was manually pulled by ropes, it opened a new chapter in the development of excavators. However, due to factors such as Otis’ early death, patent protection, and labor costs, this steam shovel failed to be widely promoted.​

After 1870, the large – scale railroad construction in the United States ushered in a golden development period for steam shovels. Their performance was continuously improved, and their application fields expanded to railroad construction, canal excavation, open – pit mine stripping, and more. In 1880, a semi – revolving steam shovel with a tractor chassis was introduced; in 1910, the first electric – driven single – bucket excavator appeared and was equipped with a crawler walking device; in 1912, gasoline and kerosene – engine – driven fully – revolving single – bucket excavators were born; in 1916, a diesel – generator – driven single – bucket excavator was introduced; in 1924, diesel – engine – direct – drive was applied to single – bucket excavators. At the same time, with the development of the automotive industry, tire – type chassis were gradually applied to small excavators; in the 1930s, walking – type walking devices emerged; in the 1940s, a suspended excavator with a tractor equipped with a hydraulic backhoe was born.​

In 1951, the French company Poclain introduced the world’s first fully hydraulic excavator, marking the entry of excavators into the era of hydraulic technology. Subsequently, companies such as Liebherr in Germany also successively produced fully hydraulic excavators. In the initial stage, due to the adoption of aircraft and machine – tool hydraulic technologies and the lack of suitable hydraulic components, the manufacturing quality of hydraulic excavators was unstable and the supporting parts were incomplete. However, since the 1960s, hydraulic excavators have entered a stage of promotion and booming development, rapidly replacing mechanical excavators.​

Since the 1970s, hydraulic excavators have widely adopted high – pressure variable systems and developed towards high – speed, high – pressure, and high – power. In the 1980s, hydraulic excavators with auxiliary electronic control systems emerged, becoming the prototype of modern hydraulic excavators. From steam – driven to electric, internal – combustion – engine – driven, and then to the application of advanced technologies such as mechatronics, intelligent technology, and remote information technology, excavators have undergone more than a hundred years of development and continuous innovation and upgrading.​

Today, excavators come in a wide variety of types, mainly divided into single – bucket excavators and multi – functional excavators. Single – bucket excavators include electric – mechanical, crawler – type hydraulic, truck – mounted, and walking – type; multi – functional excavators include backhoe loaders, amphibious, tunnel, marine, scrap – handling machines, vehicle dismantling machines, high – slope excavators, etc. Their main components include working devices, slewing mechanisms, power units, transmission mechanisms, walking devices, and auxiliary equipment. Different types of excavators also have their own unique structures, such as the turntables of single – bucket and bucket – wheel excavators, and the material – conveying devices of multi – bucket excavators. Power units include electric drive.