Inexact Restoration for Euler Discretization of Box-Constrained Optimal Control Problems

The Inexact Restoration method for Euler discretization of state and control constrained optimal control problems is studied. Convergence of the discretized (finite-dimensional optimization) problem to an approximate solution using the Inexact Restoration method and convergence of the approximate solution to a continuous-time solution of the original problem are established. It is proved that a sufficient condition for convergence of the Inexact Restoration method is guaranteed to hold for the constrained optimal control problem. Numerical experiments employing the modelling language AMPL and optimization software Ipopt are carried out to illustrate the robustness of the Inexact Restoration method by means of two computationally challenging optimal control problems, one involving a container crane and the other a free-flying robot. The experiments interestingly demonstrate that one might be better-off using Ipopt as part of the Inexact Restoration method (in its subproblems) rather than using Ipopt directly on its own.

[1]  J. M. Martínez,et al.  Local Convergence of an Inexact-Restoration Method and Numerical Experiments , 2005 .

[2]  J. M. Martínez,et al.  Inexact-Restoration Method with Lagrangian Tangent Decrease and New Merit Function for Nonlinear Programming , 2001 .

[3]  H. Sirisena,et al.  Convergence of the control parameterization Ritz method for nonlinear optimal control problems , 1979 .

[4]  José Mario Martínez,et al.  Spectral Projected Gradient Method with Inexact Restoration for Minimization with Nonconvex Constraints , 2009, SIAM J. Sci. Comput..

[5]  José Mario Martínez,et al.  Inexact restoration method for minimization problems arising in electronic structure calculations , 2011, Comput. Optim. Appl..

[6]  Andreas Fischer,et al.  A new line search inexact restoration approach for nonlinear programming , 2010, Comput. Optim. Appl..

[7]  J. M. Martínez,et al.  Euler Discretization and Inexact Restoration for Optimal Control , 2007 .

[8]  Kok Lay Teo,et al.  A Unified Computational Approach to Optimal Control Problems , 1991 .

[9]  Roberto Andreani,et al.  An inexact-restoration method for nonlinear bilevel programming problems , 2009, Comput. Optim. Appl..

[10]  Yoshiyuki Sakawa,et al.  Optimal control of container cranes , 1981, Autom..

[11]  Dimitri P. Bertsekas,et al.  Nonlinear Programming , 1997 .

[12]  Suresh P. Sethi,et al.  A Survey of the Maximum Principles for Optimal Control Problems with State Constraints , 1995, SIAM Rev..

[13]  William W. Hager,et al.  Runge-Kutta methods in optimal control and the transformed adjoint system , 2000, Numerische Mathematik.

[14]  C. Kaya,et al.  Computations for bang–bang constrained optimal control using a mathematical programming formulation , 2004 .

[15]  Brian W. Kernighan,et al.  AMPL: A Modeling Language for Mathematical Programming , 1993 .

[16]  Yoshiyuki Sakawa Trajectory planning of a free‐flying robot by using the optimal control , 1999 .

[17]  H. Maurer,et al.  Optimization methods for the verification of second order sufficient conditions for bang–bang controls , 2005 .

[18]  K. Malanowski,et al.  Error bounds for euler approximation of a state and control constrained optimal control problem , 2000 .

[19]  Richard B. Vinter,et al.  Feasible Direction Algorithm for Optimal Control Problems with State and Control Constraints: Implementation , 1999 .

[20]  H. Maurer,et al.  On L1‐minimization in optimal control and applications to robotics , 2006 .

[21]  C. Yalçin Kaya,et al.  Inexact Restoration for Runge-Kutta Discretization of Optimal Control Problems , 2010, SIAM J. Numer. Anal..

[22]  Lorenz T. Biegler,et al.  On the implementation of an interior-point filter line-search algorithm for large-scale nonlinear programming , 2006, Math. Program..

[23]  Martin Grötschel,et al.  Online optimization of large scale systems , 2001 .

[24]  Helmut Maurer,et al.  Sensitivity Analysis and Real-Time Control of a Container Crane under State Constraints , 2001 .

[25]  C. Kaya,et al.  Computational Method for Time-Optimal Switching Control , 2003 .

[26]  K. Teo,et al.  Nonlinear optimal control problems with continuous state inequality constraints , 1989 .

[27]  Rein Luus,et al.  Iterative dynamic programming , 2019, Iterative Dynamic Programming.

[28]  J. M. Martínez,et al.  Inexact-Restoration Algorithm for Constrained Optimization1 , 2000 .

[29]  William W. Hager,et al.  The Euler approximation in state constrained optimal control , 2001, Math. Comput..

[30]  Robert Baier,et al.  Approximations of linear control problems with bang-bang solutions , 2013 .

[31]  B. Mordukhovich Variational Analysis and Generalized Differentiation II: Applications , 2006 .