GB1079310A - - Google Patents

Abstract

1,079,310. Gyroscopic apparatus. SPERRY RAND CORPORATION. June 15, 1966 [June 25, 1965], No.26689/66. Heading G1C. Errors in a gyroscopically stabilized system comprising a platform 1 mounted in gimbals 8, 6, 3, are reduced by rotating the platform 1 back and forth about a vertical axis 10 through one or an integral number of complete revolutions. The platform 1 is carried by a shaft 11 mounted for rotation in a gimbal 8, the gimbal 8 being in turn mounted in a gimbal 6 for rotation about an axis 9 and in a gimbal 3 for rotation about the pitch axis 7 of the craft in which the platform 1 is mounted. The gimbal 3 is mounted with freedom about the craft roll axis 5. The platform is stabilized about the pitch axis 7 by the provision of a single degree of freedom gyroscope G1 on the platform, the gyroscope having a pickoff PO-1 controlling a motor S-22 which maintains the gimbal 6 horizontal. An acceleration sensor A-1 is coupled to a torque motor TM-1 of the gyroscope G-1 to sense the horizontal component of acceleration along the spin axis of the gyroscope. In like manner the platform is stabilized about the axis 9 by the provision of a gyroscope G-2 and acceleration sensor A-2 coupled to a motor S-11 for the gimbal 8. The pick-offs PO-1 and PO-2 of the gyroscopes G1, G2 are coupled to their respective motors by way of a resolver 12 which also senses rotation of the platform 1 relative to the gimbal 8. A pickoff 24 controls a motor S-24 to rotate the gimbal 3 to maintain the gimbal 6 level about the axis 9. A third gyroscope G-3 is provided on the platform 1 for stabilization about the vertical axis 10. The torque motor TM-3 of this gyroscope is fed with signals from a switching relay controlled by a timing device and a computer (not shown). The pick-off PO-3 of the gyroscope G-3 controls a motor S-33 which rotates the platform 1 about the vertical axis 10. The signals from the switching relay are controlled by the computer to be reversed in sign to cause the platform to rotate through one or more complete revolutions before reversal to reduce errors. By coupling these signals through the gyroscope G-3 the stabilization provided by this gyroscope about the axis 10 is preserved.