Optimal Output Regulation for Square, Over-Actuated and Under-Actuated Linear Systems

TL;DR

This paper develops optimal output regulation solutions for linear systems, addressing energy efficiency in over-actuated systems and accuracy in under-actuated systems, through new regulator equations and a linear quadratic tracking approach.

Contribution

It introduces two new sets of regulator equations for optimal output regulation, enabling energy-efficient and most accurate control solutions for different system types.

Findings

Always determine the most energy-efficient solution among classical regulator solutions.

Solvability and uniqueness are established under weak assumptions.

Provides a linear quadratic tracking approach linked to output regulation theory.

Abstract

This paper considers two different problems in trajectory tracking control for linear systems. First, if the control is not unique which is most input energy efficient. Second, if exact tracking is infeasible which control performs most accurately. These are typical challenges for over-actuated systems and for under-actuated systems, respectively. We formulate both goals as optimal output regulation problems. Then we contribute two new sets of regulator equations to output regulation theory that provide the desired solutions. A thorough study indicates solvability and uniqueness under weak assumptions. E.g., we can always determine the solution of the classical regulator equations that is most input energy efficient. This is of great value if there are infinitely many solutions. We derive our results by a linear quadratic tracking approach and establish a useful link to output regulation theory.