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Development Of Guidance, Navigation, And Control Systems For Multi-Spacecraft Assembly In Proximity Operations, Mohammed Ayman Atallah Nov 2023

Development Of Guidance, Navigation, And Control Systems For Multi-Spacecraft Assembly In Proximity Operations, Mohammed Ayman Atallah

Theses

This thesis presents the development of Guidance, Navigation, and Control (GNC) algorithms for multi-spacecraft assembly in proximity operations. A 3-DOF mathematical model of spacecraft relative translational motion is derived using the Euler-Lagrange method. Additionally, a 6-DOF mathematical model of spacecraft relative translational and rotational motion is derived using the twistor method, with consideration for the kinematic coupling effect. A new Linear Time-Invariant (LTI) model is developed based on the twistor model, which is utilized in the design of the GNC systems. Both LTI Model Predictive Control (MPC) and Linear Time-Varying (LTV) MPC algorithms are employed to develop Guidance and Control …


Experimental Validation Of An Integrated Guidance And Control System For Marine Surface Vessels, Anthony Composto Jan 2018

Experimental Validation Of An Integrated Guidance And Control System For Marine Surface Vessels, Anthony Composto

Wayne State University Dissertations

Autonomous operation of marine surface vessels is vital for minimizing human errors and providing efficient operations of ships under varying sea states and environmental conditions which is complicated by the highly nonlinear dynamics of marine surface vessels. To deal with modelling imprecision and unpredictable disturbances, the sliding mode methodology has been employed to devise a heading and a surge displacement controller. The implementation of such a controller necessitates the availability of all state variables of the vessel. However, the measured signals in the current study are limited to the global X and Y positioning coordinates of the boat that are …


Applications Of Relative Motion Models Using Curvilinear Coordinate Frames, Alex C. Perez May 2017

Applications Of Relative Motion Models Using Curvilinear Coordinate Frames, Alex C. Perez

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A new angles-only initial relative orbit determination (IROD) algorithm is derived using three line-of-sight observations. This algorithm accomplishes this by taking a Singular Value Decomposition of a 6x6 matrix to arrive at an approximate initial relative orbit determination solution. This involves the approximate solution of 6 polynomial equations in 6 unknowns. An iterative improvement algorithm is also derived that provides the exact solution, to numerical precision, of the 6 polynomial equations in 6 unknowns. The initial relative orbit algorithm is also expanded for more than three line-of-sight observations with an iterative improvement algorithm for more than three line-of-sight observations. The …


Spacecraft Guidance Techniques For Maximizing Mission Success, Shane B. Robinson May 2014

Spacecraft Guidance Techniques For Maximizing Mission Success, Shane B. Robinson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Traditional spacecraft guidance techniques have the objective of deterministically minimizing fuel consumption. These traditional approaches to guidance are developed independently of the navigation system, and without regard to stochastic effects. This work presents and demonstrates a new approach to guidance design. This new approach seeks to maximize the probability of mission success by minimizing the variance of trajectory dispersions subject to a fuel consumption constraint. The fuel consumption constraint is imposed by formulating the dynamics in terms of a steering command, and placing a constraint on the final time. Stochastic quadratic synthesis is then used to solve for the nominal …


Guidance And Navigation Linear Covariance Analysis For Lunar Powered Descent, Travis J. Moesser May 2010

Guidance And Navigation Linear Covariance Analysis For Lunar Powered Descent, Travis J. Moesser

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A linear covariance analysis is conducted to assess closed-loop guidance, navigation, and control system (GN&C) performance of the Altair vehicle during lunar powered descent. Guidance algorithms designed for lunar landing are presented and incorporated into the closed-loop covariance equations. Navigation-based event triggering is also included in the covariance formulation to trigger maneuvers and control dispersions. Several navigation and guidance trade studies are presented demonstrating the influence of triggering and guidance and study parameters on the vehicle GN&C performance.


Robust Observers And Controllers For Marine Surface Vessels Undergoing Maneuvering And Course-Keeping Tasks, Nassim Khaled Jan 2010

Robust Observers And Controllers For Marine Surface Vessels Undergoing Maneuvering And Course-Keeping Tasks, Nassim Khaled

Wayne State University Dissertations

The dynamic behavior of marine surface vessels is highly nonlinear. Moreover, it is significantly influenced by environmental disturbances induced by winds, random sea waves and currents. To yield a desired response of the ship, the guidance and control system of the ship should be robust to both modeling imprecision and significant environmental disturbances.

The focus of the current work is threefold. First, a six degree-of-freedom nonlinear model for a marine surface vessel is developed. It accounts for the coriolis and centripetal acceleration terms, added mass and wave damping terms, wave excitation forces, so-called "memory" effect terms, nonlinear restoring forces, wind …


Robust Estimation And Adaptive Guidance For Multiple Uavs' Cooperation, Randal Allen Jan 2009

Robust Estimation And Adaptive Guidance For Multiple Uavs' Cooperation, Randal Allen

Electronic Theses and Dissertations

In this paper, an innovative cooperative navigation method is proposed for multiple Unmanned Air Vehicles (UAVs) based on online target position measurements. These noisy position measurement signals are used to estimate the target's velocity for non-maneuvering targets or the target's velocity and acceleration for maneuvering targets. The estimator's tracking capability is physically constrained due to the target's kinematic limitations and therefore is potentially improvable by designing a higher performance estimator. An H-infinity filter is implemented to increase the robustness of the estimation accuracy. The performance of the robust estimator is compared to a Kalman filter and the results illustrate more …


Accurate Target Geolocation And Vision-Based Landing With Application To Search And Engage Missions For Miniature Air Vehicles, Duncan B. Barber Feb 2007

Accurate Target Geolocation And Vision-Based Landing With Application To Search And Engage Missions For Miniature Air Vehicles, Duncan B. Barber

Theses and Dissertations

Miniature air vehicles (MAVs) have attracted a large amount of interest recently both from the research community and from the public. New battery technologies as well as rapid developments in embedded processing and MEMS sensor technologies have greatly increased the potential of these vehicles. MAVs have been envisioned playing significant roles in both civil and military applications. Examples include: fire monitoring, search and rescue, traffic monitoring, crop monitoring, convoy protection, border surveillance, troop support, law enforcement, natural disaster relief, and aerial photography. The application of MAVs tends to center on the ability of the MAV to collect and deliver visual …