Excavators have a long and fascinating history, starting with early models powered by human or animal labor. These primitive machines were used for digging deep riverbeds, with bucket capacities typically not exceeding 0.2 to 0.3 cubic meters. In 1833-1836, American inventor Otis designed the first steam-powered excavator, which had an iron-wood structure, was semi-rotary, and ran on rails. It had a productivity of 35 cubic meters, but it wasn’t widely adopted due to its poor economic efficiency. The improved steam shovel eventually became commercially available in the 1970s and was used in open-pit mining. In 1880, the first semi-rotary steam shovel with a tractor chassis appeared, marking a significant step forward in excavator design. From the early 1900s until the end of the 1940s, excavators began to diversify in terms of power sources and mobility systems. By 1910, the first motor-driven single-bucket excavator was introduced, followed by a gasoline and kerosene-powered full-rotation model in 1912. In 1916, diesel-powered excavators emerged, and by 1924, direct diesel engine drives were implemented on single-bucket excavators. Crawler-type travel devices were introduced in 1910, while tire-based systems became popular as the automotive industry advanced. In the 1930s, walking excavators with pedestrian-style movement were developed, and by the mid-1950s, Germany and France introduced full-slewing hydraulic excavators, ushering in a new era of excavator development. Dudou excavators, also known as multi-dump or bucket-wheel excavators, have a history spanning over a century. In 1860, France produced the world's first and more advanced multi-dump excavator for the Suez Canal project. In 1889, the U.S. developed a multi-dump trencher capable of digging trenches up to 0.29 meters wide and 1.4 meters deep. By the late 19th century, bucket-wheel excavators were widely used in lignite mining in Germany. By 1958, each bucket could hold up to 3,600 liters, and in 1977, the Federal Republic of Germany built the largest bucket-wheel excavator in the world, with a productivity of 240,000 cubic meters per hour. These innovations highlight the continuous evolution of excavation technology, driven by industrial progress and the need for greater efficiency in mining and construction. Today, excavators come in a wide range of sizes and types, from small compact models to massive machines used in large-scale operations, all built on the foundation of these early developments. Biological Microscope,Monocular Biological Microscope,Student Medical Lab Microscope,Economical Biological Microscope Ningbo Huaguang Precision Instrument Co., Ltd. , https://www.hgopt.com