Robustness Analysis for Terminal Phases of Reentry Flight

Abstract

A novel approach to analyze the robustness of a Flight Control System (FCS) with respect to parametric uncertainties is presented, which specifically applies to gliding vehicles in the terminal phases of re-entry flight. Robustness analyses are particularly challenging for these systems. Their reference trajectories are appreciably time varying and encompass a broad variety of flight regimes. Furthermore, significant uncertainties on some critical design parameters affect the vehicle model, most notably those related to the aerodynamic behavior

A linear time-varying approach for robustness analyses of a re-entry flight technology demonstrator

“…, N S , can be obtained by employing the (n þ b) values of the above-mentioned solutions. Then, the FTSV problem may be solved exactly first obtaining at each t k the v 0 v trajectories necessary for establishing the FTS, by applying the linear transformations in (2), and then checking the validity of the m linear inequalities (7).…”

“…Let us refer to the difference between the systems solutions with and without the perturbing term d, (2), and…”

“…Flight dynamics of such vehicles are conventionally described by nonlinear systems evolving on a non-stationary trajectory [1]. Furthermore, the relatively low mechanical energy content of terminal flight phases, coupled with the poor gliding performances of re-entry vehicles in these flight regimes, implies that the vehicle rapidly traverses different flight conditions, and the trajectory evolves over a time interval that is typically in the order of minutes [2]. In addition, these missions are affected by significant uncertainties on some critical design parameters, most notably *Corresponding author: Department for Technologies, University of Naples Parthenope, Centro Direzionale C4, Napoli, 80143, Italy.…”

Robust Stability Clearance of Flight Control Law Based on Global Sensitivity Analysis

“…where (⋅) is the th eigenvalue of a matrix and Re[⋅] is the real component of a complex. The effect of on the stability of the closed loop system can be represented by (13) and SA can be invoked. It is clear that the stability analysis function (13) is also suitable for other robust stability clearance method.…”

“…AMBM analyses stable margin, robust stability and some other criteria based on advanced control theories which include (1) structural singular value ( ) analysis [4,5]; (2) polynomial-based clearance [6]; (3) v-gap analysis; (4) bifurcation and continuation method [7]; and (5) optimizationbased clearance [8]. AMBM has been improved and extended to more criteria and more types of air vehicles [9][10][11][12][13][14]. SDBM demands high fidelity simulation platform and combines experiment design techniques with decision sciences.…”