The world's first self-propelled mechanical vehicle, in other words, the world's first automobile, was built by the largely unknown French inventor Nicolas-Joseph Cugnot.Tasked by the army to develop a steam-powered vehicle for the purpose of hauling cannon, Cugnot devised a scaled-down working model in 1769, and in 1770, he unveiled a full-sized steam-driven vehicle, which he called a fardier a vapeur.Cugnot was one of the first to successfully employ a device for converting the reciprocating motion of a steam piston into a rotary motion by means of a ratchet arrangement, which was used to drive the front wheel.The vehicle was modelled after the fardier, which was a massively built two-wheeled horse-drawn cart for transporting very heavy equipment, such as cannon barrels.Nicholas-Joseph Cugnot was born in Void-Vacon, Lorraine, in 1725 and was trained as a military engineer.