In p>1769, the Frenchman N·J· Juneau made the world's first steam-driven tricycle (Figure 2, Figure 3). The car was named "Caboret", with a length of 7.32m and a height of 2.2m m. A large boiler like a pear was placed on the frame, with a front wheel diameter of 1.28 m and a rear wheel diameter of 1.5 m. When moving forward, the direction was controlled by the front wheel, and it needed to be stopped and heated for 15min every 12-15 min, and the running speed was 3.5-3.9 km/h. Later, during the test run, it hit a stone wall and was damaged. Although this invention of Juniu failed, it was a watershed between ancient transportation (powered by people, animals or sails) and modern transportation (driven by power machinery), which was of epoch-making significance. In 1786, American John Fitch invented the steam-powered ship. By 184, Dewittick had designed and manufactured a steam car, which also pulled 1 tons of goods on the railway for 15.7km. In 188, an Englishman, Richard Traversick, invented the railway steam locomotive. In 1825, an Englishman, Gerswadi Garne, built a steam bus (Figure 3) with 18 seats and a speed of 19km /h, which started the world's earliest bus operation. In 1831, Swatch Guller of the United States put a steam car into transportation, and regular transportation services appeared between Gerst and Che Luo Teng Hamm, which were 15km apart. In 1834, the earliest public automobile transportation company in the world-Scottish Steam Automobile Transportation Company was established. At that time, the driver was sitting in front of the steam car operating in Edinburgh, England, and the middle part could accommodate 2 ~ 3 passengers. The boiler position and the rear part were equipped with a fireman, and the steam engine cylinder was located under the floor in front of the rear axle to drive the rear wheel forward. However, these vehicles are as small as 3 ~ 4t and as large as 1T. They are bulky and slow, and often crash unpaved roads, causing various accidents. In 1865, Britain promulgated the world's earliest motor vehicle regulations, the so-called "red flag regulations". It is stipulated that the maximum speed of a car should not exceed 6.4km /h, and a special person must wave a red flag when driving to warn pedestrians and carriages on the road. Ironically, due to the implementation of this law, Britain lags far behind other industrial countries in the start of manufacturing cars. In 1883, the French invented the steam-powered airship. 3. Invention of Practical Internal Combustion Engine The invention of internal combustion engine started with reciprocating piston. The working principle of this internal combustion engine is that air and fuel are inhaled, the mixture is compressed and ignited, the fuel does work, and the exhaust gas generated after combustion is discharged. These are carried out continuously according to a certain travel order. In 1794, the Englishman Streeter first put forward the idea of mixing fuel and air to form a combustible mixture for combustion. In 181, Frenchman Leben put forward the principle of gas engine. In 1824, sadi carnot, a French thermal engineer, revealed the theory of "Carnot cycle" in his book Investigation on Firepower and Internal Combustion Engine. In 186, Etienne Raleigh built the internal combustion engine. In 1861, Rorschach, a French railway engineer, published the theory of four-stroke engine with equal volume combustion of intake, compression, work and exhaust. This theory later became the basis for the development of internal combustion engines. He was granted a patent by the French authorities on January 16th, 1862, but his patent failed because Rorschach defaulted on the patent fee. In 1866, nikolaus otto, a German engineer, accidentally read a newspaper report about Lenova's internal combustion engine, and made up his mind to improve it. He also studied Rorschach's four-stroke internal combustion engine, and successfully tried out an epoch-making vertical four-stroke internal combustion engine in the history of power. In 1876, the first practical piston four-stroke gas internal combustion engine was trial-produced. This single-cylinder horizontal gas machine with a power of 2.9kw has a compression ratio of 2.5 and a rotating speed of 25r/min. This internal combustion engine is known as Otto internal combustion engine (Figure 4). Otto obtained a patent on August 4, 1877. Later, people have always called the four-stroke cycle Otto cycle. Otto went down in history as the founder of the internal combustion engine, and his invention laid the foundation for the invention of the automobile. 4. The birth of the first diesel engine Both Ben Ci and Daimler invented gasoline engines. At that time, people tried to use gasoline as fuel, but also tried to use other fuels as fuel. In 1897, German rudolf diesel (1858 ~ 1913) successfully trial-produced the first diesel engine (Figure 5). It has been 2 years since the diesel engine was conceived and turned into reality. Diesel engine was trial-produced at the risk of life and amid accusations. Diesel didn't live to see the day when diesel engines were used in automobiles, but he saw with his own eyes that his invention was used in shipbuilding and replaced the steam engine with absolute superiority. Rudolf diesel was born in Paris on March 18th, 1858. Because my father was a German immigrant and was expelled by the French authorities, life at home was quite embarrassing. At the age of 12, he returned to France and entered the local technical school after graduation. Two years later, he won the national scholarship and was admitted to Munich Higher Technical School, the most famous university in Germany at that time. While studying, Diesel came up with the idea of developing a new type of economical engine. After graduation, I became a refrigerator. In order to develop an economical engine, Diesel used his spare time to start experiments with his own equipment in some small workshops. During an ammonia experiment, an explosion occurred and he almost died. In 1892, Diesel put forward the theory of compression ignition diesel engine after years of painstaking research. In 1893, the first experimental prototype was manufactured. Through experiments, Diesel decided to make some changes to the patent obtained in 1892, one of which was that pulverized coal was not used as fuel. On February 7, 1894, the second test prototype ran for 1min and turned 88 times. Diesel wrote in his diary: The first one doesn't work, the second one doesn't work well, and the third one will work well. Diesel engine was born in 1897. The appearance of diesel engine not only finds a place for diesel oil, but also saves fuel, has greater power and less pollution than gasoline. Unfortunately, Diesel, who made a great contribution to the diesel engine, ended his life on September 29th, 1929 on a ship from Antwerp to England. Rudolf diesel's invention changed the whole world. In order to commemorate him, people called diesel engine diesel engine. < /p> < /p> < /p> < /p>