Fast NMPC of a chain of masses connected by springs

Aim of this study is to compare two variants of the real-time iteration (RTI) scheme in nonlinear model predictive control (NMPC): the standard RTI scheme as described in M. Deihl (2001) and a new adjoint based RTI scheme as described in H. G. Bock et al. (2004) and L. Wirsching (2006). The authors compare their performance on returning a chain of spring connected masses to its steady state, after a strong perturbation has been exerted to the chain. The adjoint based RTI shows to be about one order of magnitude faster