A method includes trajectories of setpoints controlling a motor mechanism and auxiliary unit, the trajectory describing variation of the setpoint by position of the mobile system, the trajectories being calculated with respect to objectives according to an optimization algorithm, said method comprising: storing an approximate profile of the route as segments of straight lines, forming positions sampled along the route, a sampled position corresponding to passage from one segment to the following segment; sampling the profile according to a spatial pitch, forming a series of positions sampled along the route; the trajectories being recalculated at each sampled position by the optimization algorithm, the setpoints being constant over a given segment, a simulation predicting the energy environment of the mobile system at each sampled position as a function of the setpoints and the profile of the route, the optimization algorithm taking the simulation result to calculate the setpoints.