Finite-horizon servo SDRE for super-maneuverable aircraft and magnetically-suspended CMGs

Abstract

This work proposes a finite-horizon servo state-dependent Riccati equation (SDRE) to control two classes of aerospace systems. The SDRE is widely used for nonlinear and optimal control of different systems in theory and practice. In this work, an augmented integrator was added to the SDRE (servo SDRE) to increase performance of the controller, especially to decrease steady-state error. The finite-horizon structure developed for servo SDRE features the advantages of both methods. Attitude control of super-maneuverable aircraft was modeled and simulated. It was then compared with a conventional SDRE controller to show the advantages of the proposed combination. A magnetically suspended double-gimbal control moment gyroscope was tested using the finite-horizon servo SDRE because the control moment gyroscope is the primary attitude control actuator for spacecraft. The results showed that the servo structure improved the performance and decreased the error of the SDRE using a simple systematic approach. The finite-horizon option completes the task sooner than common controllers.