The choice of the optimization method is also critical for the performance of the system. Three methods are proposed in [13]. The explicit Model Predictive Control exhibits a low computational effort, but is only able to deal with linear problems; the parameterized MPC allows to derive a low dimensional optimization problem, that can be solved using simple solutions. According to us, the more promising technique is the online Nonlinear Model Predictive Control (NMPC), which can deal with complex nonlinear problems; it is able to evaluate the optimal solution and to stop after a fixed time if the convergence takes a long time