Slew control of prolate spinners using single magnetorquer

A novel low-cost slew algorithm was proposed for prolate spinners' attitude maneuver using single magnetorquer. The algorithm builds on the half-cone control method's philosophy, and it uses a single magnetorquer mounted along the spin axis to initiate and cancel the spin axis precession using two periods of actuations. During the first actuation, the total angular momentum change is measured by magnetic torque integration. It also uses the spacecraft attitude feedback to calculate the timing of the second actuation and introduces a timing adjustment coefficient to ensure the accuracy of precession cancellation. Based on the test results, the proposed slew algorithm provides slew performance with angular momentum error and residual nutation angles both less than 5 deg in equatorial and geomagnetic polar regions, though with different magnetorquer current directions. Further analysis on the slew performance indicates that the singlemagnetorquer slew algorithm requires the major component of the geomagnetic field to be perpendicular to the direction of the attitude maneuver.