Two Dimensional Rate Gyro Bias Estimation for Precise Pitch and Roll Attitude Determination Utilizing a Dual Arc Accelerometer Array

Abstract

In this paper, an innovative method for two%dimensi onal attitude estimation is proposed utilizing a unique dual arc accelerometer array making use of inexpensive rate sensors and gyros to measure longitudinal and transverse rotational rates in real time. The device and method proposed is composed of a two%dimensi onal sensor array fused with rate gyros and an algorithm to estimate and eliminate gyro bias online during various static and dynamic maneuvers so as to obtain a precise and reliable two dimensional attitude estimate. The method implemented utilizes the local gravitational field vector. Upon determining the location of the local gravitational field vector relative to two consecutive sensors, the orientation of the device may then be estimated and the attitude determined. However, attitude estimates and measurements produced by instantaneous rate sensors and gyroscope integration tend to drift over time due to drift and bias inherent to the rate gyro sensor. The integration of the acquired instantaneous rate signals amplify measurement errors leading to an undependable and imprecise estimate of the vehicles true attitude and orientation. The end goal of this work is to produce a precise and reliable longitudinal and transverse attitude estimation array capable of measuring rate senor and gyro bias online to produce highly accurate and reliable pitch and roll angle tracking in real%time while under subjection to simu lated vehicle flight conditions and scenarios. For this study, simulation results of the proposed method and device are presented with the inclusion of characteristic, real%world se nsor noise and bias estimates produced from corrupted and biased sensors to analyze and asses the feasibility and validity of the proposed method and system for two%di mensional attitude estimation. �omenclature