Hemispherical Resonator Gyro: Status Report and Test Results

The employment of Ring Laser Gyro (RLG) technology has been identified as an approach to provide a more accurate, highly reliable Attitude and Heading Reference System (AHRS) for helicopters. Based on this identification, a feasibility model RLG AHRS was interfaced with suitable flight test instrumentation to demonstrate its performance characteristics in flight profiles typical of Army tactical operations. In addition, the RLG AHRS was integrated with a doppler navigation system to demonstrate the improved overall navigation performance benefits achievable due to a more accurate heading input. The flight test results indicated that the RLG AHRS solves a number of the problems inherent in conventional spinning mass gyro strap-down references in high dynamic maneuvers. The paper includes a description of the RLG AHRS, flight test instrumentation, data recording, data reduction and display systems. Of particular note is the use of a standard time division multiplex data bus which interfaced all elements of the flight test configuration.