System and method for providing accurate attitude measurements at remote locations within an aircraft

摘要

An improved method and system for providing accurate attitude measurements at a location in an vehicle remote from its inertial navigation system is disclosed. A relatively low cost, lightweight attitude reference sensor is mounted in the location where accurate attitude measurements are desired. The INS and the attitude reference sensor each include gyros and accelerometers for determining attitude about and translations along pitch, yaw and roll axes. A microprocessor periodically estimates steady-state vehicle flexure between the INS and the attitude reference sensor. Gyro measurements from the attitude reference unit are directly integrated to determine the attitude of the attitude reference sensor. This output is slaved over the long term to the sum of the INS attitude and the flexure estimate to compensate continuously for drift and other errors associated with the outputs of the low cost attitude reference sensor. Long-term accuracy is assured by this slaving while short-term accuracy is assured by direct gyro integration.