Stability Analysis of the NASA ARES I Crew Launch Vehicle Control System

Dynamic modeling and ascent flight control of Ares-I Crew Launch Vehicle

“…In NASA's SAVANT program [28,29], the inertial attitude quaternion of the Ares-I are computed with respect to the ECI frame. For the Ares-I orientation on the launch pad, the x-axis of body-fixed reference frame points up to the sky, the y-axis points northward, and the z-axis points westward, as illustrated in…”

“…The Ares-I CLV is a large, slender, and aerodynamically unstable vehicle. NASA's reference model and SAVANT Simulink-based program [11,28,29], as well as various dynamic models of launch vehicles developed previously in the literature [10,16,30,31,32], were utilized to Because the Earth's orbital motion around the sun is negligible in the trajectory analysis of launch vehicles, this frame is often considered as an inertial reference frame.…”

“…29 Quaternion for a closed-loop system stabilized by the proposed control logic employing modified commanded quaternion.…”