A D4e VSA Gravimeter Stable Platform Slaved to the GEON (Gyro Erected Optical Navigation) Mark 19

Measurement of the gravity vector at sea requires stable platforms for a gravimeter and a celestial theodolite. A repeater platform slaved to the GEON Mk 19 can fulfill these requirements for the VSA gravimeter, leaving the master gyrocompass system free for the theodolite. The Mk 19 synchro roll and pitch outputs are utilized to drive the slave table, which is constructed to be carried underneath the Mk 19 and physically coupled to its reference support frame. The synchro-synchro-servo loops are stabilized by inverse feedback of the resonant frequencies resulting in the loop amplifier acting as a band reject filter.