METHOD AND APPARATUS FOR CALIBRATING GYROSCOPICALLY-STABILIZED, MAGNETICALLY- SLAVED HEADING REFERENCE SYSTEM

摘要

A heading reference system mounted in a vehicle, e.g. an aircraft or a tank, includes a magnetic compass and a gyroscope. The magnetic compass is subject to deviation in the magnetic field, hence the system must be calibrated. If the vehicle is oriented in a starting direction, and the output of the magnetic compass compared to the output of the gyroscope, an error signal is developed. This error signal is filtered to reduce noise, then stored. The vehicle is then re-oriented and the procedure repeated until sufficient information is available to calibrate the system. A microprocessor may be used for the computations and filtering of noise.