Spin free analytic platform type guidance and control system

The components of the spin free analytic satellite guidance and control system (SFAP) used for attitude reference on the M-3S Japanese launch vehicles are described. SFAP consists of attitude reference, control electronics, and actuators for each of three rocket stages. The attitude reference is performed with a single axis stabilized platform and three rate integrating gyroscopes mounted orthogonally to each other on the table. One gyro, aligned with the table axis, serves as the torque signal source. The gyros have a pulse output, each corresponding to a 2 x 10 to the -16th radian pitch/yaw attitude change. The electronic compare pitch, roll, and yaw angles with preset values, that are amenable to changes through ground control signals. The actuators include linear thrust vector controls (TVC) on the side of the first stage nozzle and an on/off system on the side of the second stage nozzle, together with hydrogen peroxide jets. Separate programs control each stage, and performance has been nominal in flight testing.