An auto-generated real-time iteration algorithm for nonlinear MPC in the microsecond range

• Published in: Automatica (Oxford) Vol. 47; no. 10; pp. 2279 - 2285
• Main Authors: Houska, Boris, Ferreau, Hans Joachim, Diehl, Moritz
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.10.2011; Elsevier
• Subjects: Applied sciences; Automatic C-code generation; Computer science; control theory; systems; Control theory. Systems; Dynamical systems; Exact sciences and technology; Exports; International trade; Language processing and microprogramming; Mathematical models; Modelling and identification; Nonlinear dynamics; Nonlinear model predictive control; Nonlinearity; Optimal control; Predictive control; Real time; Real-time algorithms; Software; Nonlinear model predictive control; Real-time algorithms; Automatic C-code generation; Code generation; Gauss Newton method; Non linear control; Symbolic language; Software package; Feedback regulation; Finite automaton; Dynamical system; C language; Non linear system; Real time; Model predictive control; Millisecond; Software tool; Optimal control; Non linear model; Automatic generation; Integrator; System identification
• ISSN: 0005-1098; 1873-2836
• DOI: 10.1016/j.automatica.2011.08.020

In this paper, we present an automatic C-code generation strategy for real-time nonlinear model predictive control (NMPC), which is designed for applications with kilohertz sample rates. The corresponding code export module has been implemented within the software package ACADO Toolkit. It is capable of exporting fixed step-size integrators together with their sensitivities as well as a real-time Gauss–Newton method. Here, we employ the symbolic representation of optimal control problems in ACADO in order to auto-generate plain C-code which is optimized for final production. The exported code has been tested for model predictive control scenarios comprising constrained nonlinear dynamic systems with four states and a control horizon of ten samples. The numerical simulations show a promising performance of the exported code being able to provide feedback in much less than a millisecond.