Nicolas-Joseph Cugnot is recognised as building the first self-propelled vehicle to transport man. Cugnot was at the time an engineer in the French Army.
Steam power has been used since the early 1700’s for fixed machines that pumped water from mines, or raised heavy equipment. It was not known at the time how to convert the back and forth pass motion of steam power into a rotary movement to make a wheel turn. Cugnot solved this problem and in 1769 built a full size prototype vehicle based on a model he had made some six years earlier. His Steam Dray (fardier a vapeur) had 3-wheels with iron rims, two wheels were at the back with the one wheel in front.
The vehicle carried a front mounted boiler and a two-cylinder engine located over the front wheel. Cugnot’s vehicle worked but needed to stop every 10 - 12 minutes to rebuild enough steam pressure to continue. The vehicle had a top speed of 2mph and eventually caused the world’s first automobile accident when it ran out of control and demolished a garden wall. ( A reconstruction of this event can be seen on YouTube)