Electronic Tripod Technique.
DEPARTMENT OF THE AIR FORCE WASHINGTON DC
Pagination or Media Count:
An electronic tripod technique for postlaunch alignment of the roll and pitch gyros of a missile inertial guidance system. Prior to launch, missile gyros are spun up and caged to the missile airframe axes. At launch, gyros are uncaged and slant range to ground measured over an azimuthal sweep symmetrical to the plane of the missiles roll and yaw axes. A roll error signal proportional to the difference between the slant ranges at the sweep extremes is generated and used to torque the roll gyro, resulting in a rotation of the missile about its roll axis until the error signal is zero. This establishes a new roll reference at the roll gyro that is normal to the local vertical. A pitch error signal is then generated that is proportional to the difference between the slant range at either sweep extreme and the slant range at 0 deg azimuth. Similarly, this signal is used to torque the pitch gyro and establish a new pitch reference normal to the local vertical, thus completing the alignment of the roll and pitch gyros to the local vertical. Author
- Guided Missile Trajectories, Accuracy and Ballistics