Handling constraints in optimal control with saturation functions and system extension
FakultätenFakultät für Ingenieurwissenschaften und Informatik
LizenzCC BY-NC-ND 3.0 Deutschland
The paper presents a systematic approach to transform a general inequality-constrained optimal control problem (OCP) into a new equality-constrained one by means of saturation functions. The transformed OCP can be handled in the standard calculus of variations. The presented transformation substitutes the state constraints by constructing dynamical subsystems, which constitute a (dynamical) system extension. The dimension of the subsystems corresponds to the relative degree (or order) of the respective state constraints. The approach results in a new equality-constrained OCP with extended state and input vectors. The new OCP can be solved in a convenient manner, since the stationarity conditions are easily determined and exploited. An important aspect of the saturation function formulation is that the constraints cannot be violated during the numerical solution. The approach is illustrated for an extended version of the well-known Goddard problem with thrust and dynamic pressure constraints and using a collocation method for its numerical solution.
Erstellung / Fertigstellung
OriginalpublikationSystems & control letters 59 (2010), S. 671 - 679
Normierte SchlagwörterOptimale Kontrolle [GND]
Collocation methods [LCSH]