Vehicle speed control method with alternation of active motion and passive motion

A method of controlling the speed of a vehicle (1); the control method includes the steps of: determining, during a step of designing, a table (15) of motion that determines, as a function of the cruise speed (V C ), whether it is more convenient to proceed at a constant speed or to proceed at a variable speed; determining a desired cruise speed (V C ) of the vehicle (1); verifying, using the table (15) of motion whether, at the desired cruise speed (V C ), it is more convenient to proceed at a constant speed or to proceed at a variable speed; and piloting, if according to the table (15) of motion it is more convenient to proceed at a constant speed, a heat engine (4) and a transmission (5) of the vehicle (1) in order to cyclically alternate a period of active motion, in which the engine (4) is on and transmits a positive torque to the driving wheels (3), and a period of passive motion, in which the engine (4) is stopped and disconnected from the driving wheels (3).