Navigation, Guidance, Control and Dynamics Commons^™

Single-Degree-Of-Freedom Experiments Demonstrating Electromagnetic Formation Flying For Small Satellite Swarms Using Piecewise-Sinusoidal Controls, Ajin Sunny

Theses and Dissertations--Mechanical and Aerospace Engineering

This thesis presents a decentralized electromagnetic formation flying (EMFF) control method using frequency-multiplexed sinusoidal control signals. We demonstrate the EMFF control approach in open-loop and closed-loop control experiments using a single-degree-of-freedom testbed with an electromagnetic actuation system (EAS). The EAS sense the relative position and velocity between satellites and implement a frequency-multiplexed sinusoidal control signal. We use a laser-rangefinder device to capture the relative position and an ARM-based microcontroller to implement the closed-loop control algorithm. We custom-design and build the EAS that implements the formation control in one dimension. The experimental results in this thesis demonstrate the feasibility of the …

Direct Adaptive Control For A Trajectory Tracking Uav, Nirmit Prabhakar

Doctoral Dissertations and Master's Theses

This research focuses on the theoretical development and analysis of a direct adaptive control algorithm to enable a fixed-wing UAV to track reference trajectories while in the presence of persistent external disturbances. A typical application of this work is autonomous flight through urban environments, where reference trajectories would be provided by a path planning algorithm and the vehicle would be subjected to significant wind gust disturbances. Full 6-DOF nonlinear and linear UAV simulation models are developed and used to study the performance of the direct adaptive control system for various scenarios. A stability proof is developed to prove convergence of …

Active Permanent Magnet Attitude Control For Cubesats Using Mu-Metal Shielding, Maxwell Martin

Mechanical Engineering Undergraduate Honors Theses

Cube-Satellites (CubeSats) are nanosatellites composed of cube shaped units, each nominally 10cm to a side and around 1kg in mass. Due to their inherent size and weight limitations, it is often impractical to use conventional attitude, or rotational, control methods such as thrusters on these small satellites. Several methods, including magnetorquer rods and small reaction wheels, are often used instead of traditional methods to work around the size and weight limitations. As a new alternative to these methods, a permanent magnet mounted on a rotatable shaft could be used to achieve attitude control. In much the same way that a …

Space Operations In The Suborbital Space Flight Simulator And Mission Control Center: Lessons Learned With Xcor Lynx, Pedro Llanos, Christopher Nguyen, David Williams, Kim O. Chambers, Erik Seedhouse, Robert Davidson

Journal of Aviation/Aerospace Education & Research

This study was conducted to better understand the performance of the XCOR Lynx vehicle. Because the Lynx development was halted, the best knowledge of vehicle dynamics can only be found through simulator flights. X-Plane 10 was chosen for its robust applications and accurate portrayal of dynamics on a vehicle in flight. The Suborbital Space Flight Simulator (SSFS) and Mission Control Center (MCC) were brought to the Applied Aviation Sciences department in fall 2015 at Embry-Riddle Aeronautical University, Daytona Beach campus. This academic and research tool is a department asset capable of providing multiple fields of data about suborbital simulated flights. …

Design Of Shape-Conforming Nosecone For Optimal Fluid Flow From Transonic To Supersonic Range, Anna Tombazzi

Williams Honors College, Honors Research Projects

Modern flight vehicles, such as rockets, missiles, and airplanes, experience a force caused by forebody wave drag during the flight. This drag force is induced when the frontal point of each vehicle breaks the pressure wave during flight. Efforts to reduce this wave drag force to improve flight efficiency include modifying the nosecone profile of the flight vehicles to lower the drag force.

This project revolved around creating a design to make the transformation of nosecone shapes from a ¾ Parabolic profile to a ½ Power Series profile possible, mid-flight. Using a novel nosecone assembly, shape memory alloys (SMAs) and …

Instrumentation And Inertial Navigation Systems Design For Tensegrity Robot Implementations, Scott Edward Harper

Graduate Theses, Dissertations, and Problem Reports (ETD)

One of the major challenges faced when developing missions for the exploration of planetary bodies is the risk these terrains pose on the science platform when using a traditional lander or wheeled rover. One means of developing platforms to traverse these harsh terrains is to utilize mobility systems comprised of tensegrity structures. These structures have the capacity to distribute loads across a network of axially loaded members such that they can be constructed in a very lightweight manner and morph their geometries when required. In literature, there has been significant progress in simulated environments to utilize tensegrity structures as mobility …

University Of Minnesota Smallsat And High Altitude Ballooning Development And Collaboration, Luke Zumwalt, Ricardo Saborio, Athanasios Pantazides, Aaron Nightingale, Demoz Gebre Egziabher, Lindsay Glesener

2017 Academic High Altitude Conference

The Experiment for X-ray Characterization and Timing (EXACT) mission is a 3U CubeSat technology-development project being built by the SmallSat team at the University of MN – Twin Cities which is a joint research effort of the Aerospace Engineering and Mechanics (AEM) Department and the School of Physics and Astronomy (SPA). The main objective of this spacecraft is to carry a payload including a detector designed to measure energy and time of arrival time of individual hard x-ray photons emitted from the Sun and from other astrophysical sources. During the development process for EXACT, flights provided by the High-Altitude Student …

Time Optimal State Feedback Control With Application To A Spacecraft With Cold Gas Propulsion, Samuel J. Kitchen-Mckinley, Sergey V. Drakunov

Publications

A cold gas propulsion system is well suited to provide the required thrust for a small surveyor spacecraft operated near an asteroid or planetary surface. The cold gas propellant can obtained in-situ from local surface or atmospheric constituents. For small spacecraft, the cold gas system may be limited to only on-off control of the main tank where the generated thrust is directly dependent on the tank pressure. As such the thrust will slowly decrease as the propellant is expended. A state feedback, time optimal, control law is developed for a vehicle with propellant is expended. A state feedback, time optimal, …

Implementing Delay-Tolerant Networking At Morehead State University, Nathaniel J. Richard

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science by Nathaniel J. Richard on April 28, 2017.

A Novel Approach For Controlled Deorbiting And Reentry Of Small Spacecraft, Larry H. Fineberg, Justin Treptow, Timothy Bass, Scott Clark, Yusef Johnson, Bradley Poffenberger

Space Traffic Management Conference

No abstract provided.

Adaptive Estimation And Heuristic Optimization Of Nonlinear Spacecraft Attitude Dynamics, Joshuah A. Hess

Theses and Dissertations

For spacecraft conducting on-orbit operations, changes to the structure of the spacecraft are not uncommon. These planned or unanticipated changes in inertia properties couple with the spacecraft's attitude dynamics and typically require estimation. For systems with time-varying inertia parameters, multiple model adaptive estimation (MMAE) routines can be utilized for parameter and state estimates. MMAE algorithms involve constructing a bank of recursive estimators, each assuming a different hypothesis for the systems dynamics. This research has three distinct, but related, contributions to satellite attitude dynamics and estimation. In the first part of this research, MMAE routines employing parallel banks of unscented attitude …

Early Afternoon Concurrent Panel Sessions: Commercial Space Industry Snapshot: Presentation: Small Catapult-Assisted Horizontal-Launch Reusable Rbcc Ssto Spaceplane For Economical Short-Duration Leo Access, Nihad E. Daidzic,

Aviation / Aeronautics / Aerospace International Research Conference

This article discusses the conceptual design, flight trajectory calculations, and utilization of the possible future horizontally-launched reusable Single-Stage-to-Orbit (SSTO) spaceplane for small payload short-duration manned/unmanned access to Low-Earth-Orbit (LEO). The 10,000 lb spaceplane would use 5,000 ft catapult-assist horizontal-launch facility and conduct powered approach and landing on conventional horizontal paved runways following the gliding atmospheric re-entry. To increase the economy of operation, the launch facility located at high elevations (4,000+ ft) equatorial region is required, such as, the plateaus in Kenya and Tanzania in Africa and/or Ecuador in South America. A 500-lb payload, including pilot-commander, is envisioned. The propulsion cycle …

Small Satellite Noncommutative Rotation Sequence Attitude Control Using Piezoelectric Actuators, Joshua L. Evans

Theses and Dissertations--Electrical and Computer Engineering

Attitude control remains one of the top engineering challenges faced by small satellite mission planning and design. Conventional methods for attitude control include propulsion, reaction wheels, magnetic torque coils, and passive stabilization mechanisms, such as permanent magnets that align with planetary magnetic fields. Drawbacks of these conventional attitude control methods for small satellites include size, power consumption, dependence on external magnetic fields, and lack of full control authority. This research investigates an alternative, novel approach to attitude-control method for small satellites, utilizing the noncommutative property of rigid body rotation sequences. Piezoelectric bimorph actuators are used to induce sinusoidal small-amplitude satellite …

Attitude Determination & Control System Design And Implementation For A 6u Cubesat Proximity Operations Mission, Francisco J. Franquiz

Doctoral Dissertations and Master's Theses

The purpose of this work is to discuss the attitude determination and control system (ADCS) design process and implementation for a 12 kg, 6U (36.6 cm x 23.9 cm x 27.97 cm) CubeSat class nano-satellite. The design is based on the requirements and capabilities of the Application for Resident Space Object Proximity Analysis and IMAging (ARAPAIMA) proximity operations mission. The satellite is equipped with a cold gas propulsion system capable of exerting 2.5 mN m torques in both directions about each body axis. The attitude sensors include an angular rate gyro and star tracker (STR), supplemented by the payload optical …

Navigation Constellation Design Using A Multi-Objective Genetic Algorithm, Heather C. Diniz

Theses and Dissertations

In satellite constellation design, performance and cost of the system drive the design process. The Global Positioning System (GPS) constellation is currently used to provide positioning and timing worldwide. As satellite technology has improved over the years, the cost to develop and maintain the satellites has increased. Using a constellation design tool, it is possible to analyze the tradeoffs of new navigation constellation designs (Pareto fronts) that illustrate the tradeoffs between position dilution of precision (PDOP) and system cost. This thesis utilized Satellite Tool Kit (STK) to calculate PDOP values of navigation constellations, and the Unmanned Spacecraft Cost Model (USCM) …

A Monocular Slam Method To Estimate Relative Pose During Satellite Proximity Operations, Scott J. Kelly

Theses and Dissertations

Automated satellite proximity operations is an increasingly relevant area of mission operations for the US Air Force with potential to significantly enhance space situational awareness (SSA). Simultaneous localization and mapping (SLAM) is a computer vision method of constructing and updating a 3D map while keeping track of the location and orientation of the imaging agent inside the map. The main objective of this research effort is to design a monocular SLAM method customized for the space environment. The method developed in this research will be implemented in an indoor proximity operations simulation laboratory. A run-time analysis is performed, showing near …

Dynamic Simulation Of Aerial Trolley Alternative To The Mighty Eagle, Jerry Sweafford

Von Braun Symposium Student Posters

No abstract provided.

Trajectory Optimization For A Misson To The Trojan Asteroids, Shivaji Senapati Gadsing

Masters Theses

The problem of finding a minimum-fuel trajectory for a mission to the Jovian Trojan asteroids is considered. The problem is formulated as a modified traveling salesman problem. Two different types of algorithms such as an exhaustive search algorithm and a serial rendezvous search algorithm are developed. The General Mission Analysis Tool (GMAT) is employed for finding optimum trajectories with minimal fuel consumption. The selection of a minimum-fuel mission trajectory, and the associated target asteroids, will be a key factor in determining feasibility and scientific value of a Trojan tour and rendezvous mission.

The transfer trajectory followed by a spacecraft between …

Feasibility Of Cubesat Formation Flight Using Rotation To Achieve Differential Drag, Skyler M. Shuford

Aerospace Engineering

This paper presents the results of a study conducted to understand the feasibility of CubeSat formation flight. The mechanism for separation and formation studied was differential drag, achieved by rotating the CubeSats to give them different cross-sectional areas. Intuitively, lower altitude orbits provide much higher separation effects. Although the most influential orbital effects occur with maximum and minimum cross-sectional areas, an attitude-controlled and a tumbling CubeSat may provide enough differential drag to meet separation requirements of a mission. Formation flight is possible, but due to the non-linearity of the system, gain scheduling may be the most effective method of long …

Feasibility Of Microsatellite Active Debris Removal Systems, Karsten J. James

Master's Theses

Space debris has become an increasingly hazardous obstacle to continued spaceflight operations. In an effort to mitigate this problem an investigation of the feasibility of a microsatellite active debris removal system was conducted. Through proposing a novel concept of operation, utilizing a grapple-and-tug system architecture, and by analyzing each resultant mission phase in the frame of a representative example, it was found that microsatellite scale systems are capable of fulfilling the active debris removal mission. Analysis of rendezvous, docking, control and deorbit mission requirements determined that the design of a grapple-and-tug system will be driven by sizing of the propellant …

An Attitude Determination System With Mems Gyroscope Drift Compensation For Small Satellites, Maxwell Bezold

Theses and Dissertations--Electrical and Computer Engineering

This thesis presents the design of an attitude determination system for small satellites that automatically corrects for attitude drift. Existing attitude determination systems suffer from attitude drift due to the integration of noisy rate gyro sensors used to measure the change in attitude. This attitude drift leads to a gradual loss in attitude knowledge, as error between the estimated attitude and the actual attitude increases.

In this thesis a Kalman filter is used to complete sensor fusion which combines sensor observations with a projected attitude based on the dynamics of the satellite. The system proposed in this thesis also utilizes …

Visual Attitude Propagation For Small Satellites, Samir Ahmed Rawashdeh

Theses and Dissertations--Electrical and Computer Engineering

As electronics become smaller and more capable, it has become possible to conduct meaningful and sophisticated satellite missions in a small form factor. However, the capability of small satellites and the range of possible applications are limited by the capabilities of several technologies, including attitude determination and control systems. This dissertation evaluates the use of image-based visual attitude propagation as a compliment or alternative to other attitude determination technologies that are suitable for miniature satellites. The concept lies in using miniature cameras to track image features across frames and extracting the underlying rotation.

The problem of visual attitude propagation as …

Development Of A Pyrotechnic Shock Simulation Apparatus For Spacecraft Applications, Joseph Binder, Matthew Mccarty, Chris Rasmussen

Aerospace Engineering

This report details the research, design, construction, and testing of a pyrotechnic shock simulation apparatus for spacecraft applications. The apparatus was developed to be used in the Space Environments Lab at California Polytechnic State University. It will be used for testing spacecraft components with dimensions up to 24”x12”x12” as well as CubeSats. Additionally, it may be used as an instructional or demonstrational tool in the Aerospace Department’s space environments course. The apparatus functions by way of mechanical impact of an approximately 20 lb stainless steel swinging hammer. Tests were performed to verify the simulator’s functionality. Suggestions for improvement and further …

Sun-Synchronous Orbit Slot Architecture Analysis And Development, Eric Watson

Master's Theses

Space debris growth and an influx in space traffic will create a need for increased space traffic management. Due to orbital population density and likely future growth, the implementation of a slot architecture to Sun-synchronous orbit is considered in order to mitigate conjunctions among active satellites. This paper furthers work done in Sun-synchronous orbit slot architecture design and focuses on two main aspects. First, an in-depth relative motion analysis of satellites with respect to their assigned slots is presented. Then, a method for developing a slot architecture from a specific set of user defined inputs is derived.

An Analysis Of Stabilizing 3u Cubesats Using Gravity Gradient Techniques And A Low Power Reaction Wheel, Erich Bender

Aerospace Engineering

The purpose of this paper is to determine the feasibility of gravity gradient stabilizing a 3U CubeSat and then using a miniature reaction wheel to further increase stability characteristics. This paper also serves as a guide to understanding and utilizing quaternions in attitude control analysis. The analytical results show that using 33 centimeter booms and 400 gram tip masses, a 3U CubeSat will experience a maximum of 6 degrees of angular displacement in yaw and pitch, and less than .5 degrees of angular displacement in the nadir axis. A .120 kilogram miniature reaction wheel developed by Sinclair Interplanetary was introduced …

Translational And Rotational Control Of An Asteroid Orbiting Satellite, Takahiro Kuhara

Doctoral Dissertations and Master's Theses

The objective of this thesis is to analyze an effective control scheme for an asteroid orbiting satellite. The thesis first summarizes the progress made in the dynamics formulation of such satellites and then provides a theoretical framework for the control system design. The control objective is to maintain a nadir pointing attitude on a circular equatorial orbit. Using established control design techniques, feedback laws are constructed to control both rotational and translational motion of the satellite so that the control objective is achieved. Computer simulations are carried out to illustrate the effectiveness of the control laws.

Orbital Tori Construction Using Trajectory Following Spectral Methods, Ralph E. Bordner Iii

Theses and Dissertations

By assuming the motion of a satellite about the earth’s geopotential mimics the known Kolmogorov-Arnold-Moser (KAM) solution of a lightly perturbed integrable Hamiltonian system, this research focused on applying trajectory following spectral methods to estimate orbital tori from sampled orbital data. From an estimated basis frequency set, orbital data was decomposed into multi-periodic Fourier series, essentially compressing ephemerides for long-term use. Real-world Global Positioning System (GPS) orbital tracks were decomposed and reconstructed with error from as low as few kilometers per coordinate axis over a 10-week span to tens of kilometers per coordinate axis over the same time period, depending …

Estimating Characteristics Of A Maneuvering Reentry Vehicle Observed By Multiple Sensors, Evan M. Brooks

Theses and Dissertations

Post flight analysis of ballistic missile reentry vehicles is an area of focus for the U.S. Government, especially for those involved in ballistic missile defense. Typically, this analysis incorporates either a model-driven least squares filter or a data-following Kalman filter. The research performed here developed a filter that attempts to integrate the strengths of both filters. A least squares filter operates on observation data collected during exoatmospheric free flight and a Kalman filter is used to analyze data collected lower in the atmosphere, where potential maneuvers could be performed. Additionally, the filter was written to incorporate data from multiple sensors. …

Development Of A Remotely Operated Autonomous Satellite Tracking System, Michael E. Graff

Theses and Dissertations

AFIT is currently developing a capability to remotely and autonomously track LEO satellites using commercial telescopes. Currently, the system is capable of open-loop tracking based on Two-Line Element sets (TLEs) downloaded from NORAD’s space object catalog. The ability to actively track using a closed-loop control system would allow tracking of satellites which deviated from the published TLEs along with providing some information about the object’s new orbital elements. To accomplish closed-loop tracking, the object is imaged by a digital camera connected to a wide field-of-view (WFOV) spotting scope. Software was developed to provide azimuth and elevation inputs in order to …

Orbit Maneuver For Responsive Coverage Using Electric Propulsion, Timothy S. Hall

Theses and Dissertations

The use of continuous electric propulsion to manipulate a satellite’s orbit offers significant potential for enhancing coverage of a target in ways not previously considered. Elliptical orbits utilizing a very low perigee can facilitate access to the surface and atmosphere of the Earth at sub-ionosphere altitudes while counteracting atmospheric drag forces using continuous electric propulsion. Additionally, in-plane and out-of-plane manipulation of both circular and elliptical orbits can allow for passage of a satellite over a target at a given time. Sustained low perigee orbit was modeled with an initial perigee altitude of 100 km and various apogee altitudes to derive …