An attitude reconstruction algorithm has been developed for a flexible sounding rocket whose spin vector nutates unstably about its minor inertia axis. This algorithm deduces attitude for use in post-flight analysis of the sounding rocket's science data. An additional motive for pursuing this work has been to show that a flexible-body dynamic model can be used in a Kalman filter/smoother-type a...

Title of Dissertation: THE MULTIDIMENSIONAL GENERALIZED GRADED UNFOLDING MODEL FOR ASSESSING CHANGE IN REPEATED MEASURES Weiwei Cui Doctor of Philosophy, 2008 Directed by: Associate Professor James S. Roberts Department of Psychology A multidimensional extension of the generalized graded unfolding model for repeated measures (GGUM-RM) is introduced and applied to analyze attitude change across ...

This paper presents a Vehicle Dynamics (VD) aiding technique to enhance position, velocity, and attitude error estimation in low-cost Inertial Navigation Systems (INS), with application to Underwater Vehicles (UV). The VD model is directly embedded in an Extended Kalman Filter (EKF) and provides specific information about the rigid body tridimensional motion unavailable from the INS computation...

A novel adaptive unscented Kalman filter (AUKF) based estimation algorithm is proposed for a 3U Cubsat. This small satellite employs a three axis magnetometer and three MEMS gyroscopes as well as three magnetic torque rods and one reaction wheel on the pitch axis. Unlike the existing UKF, in this paper, an n+1 sigma set is used to estimate the nanosatellite attitude instead of 2n + 1 sigma poin...

In general, the information of mass properties is required to control a spacecraft. The mass properties, mass and inertia, are changed by some activities, e.g., consumption of propellant, deployment of solar panel, sloshing, etc. Various estimation methods have been studied to obtain the accurate mass properties. The gyro-based attitude data including noise and bias needs to be compensated for ...

This paper presents an algorithm to average a set of quaternion observations. The average quaternion is determined by minimizing the weighted sum of the squared Frobenius norms of the corresponding attitude matrix differences, subject to the unit-norm constraint in the determined solution. Two cases are presented: one that incorporates scalar weights and one that incorporates general weights on...

This paper considers a robust strong tracking nonlinear filtering problem in the case there are model uncertainties including the model mismatch, unknown disturbance and status mutation in the spacecraft attitude estimation system with quaternion constraint. Two multiple fading factor matrices are employed to regulate the prediction error covariance matrix, which guarantees its symmetry. The sp...

The extended Kalman filter (EKF) and unscented Kalman filter (UKF) for nonlinear state estimation with both additive and nonadditive noise structures are presented and compared. Three different Global Positioning System (GPS)/inertial navigation system (INS) sensor fusion formulations for attitude estimation are used as case studies for the nonlinear state estimation problem. A diverse set of a...

In this study Fault Detection and Isolation (FDI) in the attitude determination and control system of Low Earth Orbit (LEO) satellite is investigated. Attitude determination system uses algebraic method. This method is based on computing any two analytical vectors in the reference frame and measuring these vectors in the body coordinate system (Barishev & Krilov, 1968; Wertz, 1988). As measurin...

This article presents a robust and almost global feedback attitude tracking control scheme in conjunction with a robust deterministic estimator that constructs state estimates for feedback. These control and the estimation schemes use the natural and globally unique representation of rigid body attitude provided by rotation matrices. Attitude and angular velocity state estimates are constructed...