Slew Control of Prolate Spinners Using Single Magnetorquer

Abstract

= angular momentum of spacecraft, that in reference inertial/spacecraft-fixed body coordinates, that after H t = the first actuation, that at end of the slew, and the target angular momentum, N · ms I, I z , I t = spacecraft moment of inertia matrix, moment of inertia of transverse axis/spin axis, kg · m 2 k = rotation number around spin axis of the spacecraft m = magnetic moment of the magnetorquer dipole, A · m 2 T, T magnet = control torque/ magnetic torque applied to the spacecraft, N · m t 0 , t 1f , t 2s , t 2f , t 1;2 , Δt 2 , t ⌢ 2 = time of the start, time at the end of the first actuation, time of the start of the second actuation, time at the end of second actuation, time interval between first and second actuation, the actuating duration of the second actuation and the predicted meantime of second actuation, s Z 0 , Z 1f , Z f , Z ins , Z t = spin axis of the initial/after the first actuation/after the slew/of an instant time and of the target orientation β = slew angle, deg γ = residual precession angle after the first actuation of slew, deg θ = nutation angle, deg λ = inertia ratio of spin axis and transverse axis moment of inertia ξ = the second actuation time adjustment coefficient ω, ω Z , ω XY , ω N , ω H = angular velocity of the spacecraft, that in spin axis, that in the X − Y plane, body nutation rate, and inertial nutation rate, rad∕s

Feedback slew algorithms for prolate spinners using Single–Thruster

“…Pulse-train algorithms can also be used for oblate spacecraft. Based on the Half-Cone slew using single-thruster, similar Half-Cone slew method using single-magnetorquer [7] are also developed aimed to apply on STRaND-1 [8] mission.…”