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Full-Text Articles in Engineering

Six-Degree-Of-Freedom Optimal Feedback Control Of Pinpoint Landing Using Deep Neural Networks, Omkar S. Mulekar, Hancheol Cho, Riccardo Bevilacqua Nov 2023

Six-Degree-Of-Freedom Optimal Feedback Control Of Pinpoint Landing Using Deep Neural Networks, Omkar S. Mulekar, Hancheol Cho, Riccardo Bevilacqua

Student Works

Machine learning regression techniques have shown success at feedback control to perform near-optimal pinpoint landings for low fidelity formulations (e.g. 3 degree-of-freedom). Trajectories from these low-fidelity landing formulations have been used in imitation learning techniques to train deep neural network policies to replicate these optimal landings in closed loop. This study details the development of a near-optimal, neural network feedback controller for a 6 degree-of-freedom pinpoint landing system. To model disturbances, the problem is cast as either a multi-phase optimal control problem or a triple single-phase optimal control problem to generate examples of optimal control through the presence of disturbances. …


Stability Of Deep Neural Networks For Feedback-Optimal Pinpoint Landings, Omkar S. Mulekar, Hancheol Cho, Riccardo Bevilacqua Oct 2023

Stability Of Deep Neural Networks For Feedback-Optimal Pinpoint Landings, Omkar S. Mulekar, Hancheol Cho, Riccardo Bevilacqua

Student Works

The ability to certify systems driven by neural networks is crucial for future rollouts of machine learning technologies in aerospace applications. In this study, the neural networks are used to represent a fuel-optimal feedback controller for two different 3-degree-of-freedom pinpoint landing problems. It is shown that the standard sum-ofsquares Lyapunov candidate is too restrictive to assess the stability of systems with fuel-optimal control profiles. Instead, a parametric Lyapunov candidate (i.e. a neural network) can be trained to sufficiently evaluate the closed-loop stability of fuel-optimal control profiles. Then, a stability-constrained imitation learning method is applied, which simultaneously trains a neural network …


Assessing High Dynamic Range Imagery Performance For Object Detection In Maritime Environments, Erasmo Landaeta Apr 2023

Assessing High Dynamic Range Imagery Performance For Object Detection In Maritime Environments, Erasmo Landaeta

Doctoral Dissertations and Master's Theses

The field of autonomous robotics has benefited from the implementation of convolutional neural networks in vision-based situational awareness. These strategies help identify surface obstacles and nearby vessels. This study proposes the introduction of high dynamic range cameras on autonomous surface vessels because these cameras capture images at different levels of exposure revealing more detail than fixed exposure cameras. To see if this introduction will be beneficial for autonomous vessels this research will create a dataset of labeled high dynamic range images and single exposure images, then train object detection networks with these datasets to compare the performance of these networks. …


Neural Network Fusion Of Multi-Modal Sensor Data For Autonomous Surface Vessels, David J. Thompson Apr 2023

Neural Network Fusion Of Multi-Modal Sensor Data For Autonomous Surface Vessels, David J. Thompson

Doctoral Dissertations and Master's Theses

Autonomous surface vessels (ASV) can potentially improve the safety of vessels traditionally operated by humans. Despite advancements in autonomous on-road vehicles, many of these advancements have yet to be realized for ASVs. This is primarily due to lacking ASV sensing platforms and public datasets for ASV-based perception research. To that end, this dissertation demonstrates the design of a synchronized multi-modal sensing platform for ASVs utilizing GPS/INS, LiDAR, LWIR cameras, HDR camera, and high-resolution cameras. The sensing platform is designed to maximize the overlap of sensors for multi-modal research and provides accurate intrinsic and extrinsic calibration between each sensor. Furthermore, the …


Alternatives To Reducing Aviation Fuel-Burn With Technology: Fully Electric Autonomous Taxibot, Denzil Neo Jan 2023

Alternatives To Reducing Aviation Fuel-Burn With Technology: Fully Electric Autonomous Taxibot, Denzil Neo

Student Works

Aircraft taxiing operations in the aerodrome were identified to consume the most jet fuel apart from the cruise phase of the flight. This was also well supported by various research associating taxi operations at large, congested airports, with high jet fuel consumption, high carbon emissions, and noise pollution. Existing literature recognised the potential to address the environmental issues of aerodrome taxi operations by operating External or Onboard Aircraft Ground Propulsion Systems (AGPS). Designed to power aircraft with sources other than their main engines, external Aircraft Ground Power Systems (AGPS) have shown the potential to significantly cut jet fuel consumption and …


Certification Basis For A Fully Autonomous Uncrewed Passenger Carrying Urban Air Mobility Aircraft, Steve Price Dec 2022

Certification Basis For A Fully Autonomous Uncrewed Passenger Carrying Urban Air Mobility Aircraft, Steve Price

Student Works

The Urban Air Mobility campaign has set a goal to efficiently transport passengers and cargo in urban areas of operation with autonomous aircraft. This concept of operations will require aircraft to utilize technology that currently does not have clear regulatory requirements. This report contains a comprehensive analysis and creation of a certification basis for a fully autonomous uncrewed passenger carrying rotorcraft for use in Urban Air Mobility certified under Title 14 Code of Federal Regulations Part 27. Part 27 was first analyzed to determine the applicability of current regulations. The fully electric propulsion system and fully autonomous flight control system …


Robotic Olfactory-Based Navigation With Mobile Robots, Lingxiao Wang Dec 2021

Robotic Olfactory-Based Navigation With Mobile Robots, Lingxiao Wang

Doctoral Dissertations and Master's Theses

Robotic odor source localization (OSL) is a technology that enables mobile robots or autonomous vehicles to find an odor source in unknown environments. It has been viewed as challenging due to the turbulent nature of airflows and the resulting odor plume characteristics. The key to correctly finding an odor source is designing an effective olfactory-based navigation algorithm, which guides the robot to detect emitted odor plumes as cues in finding the source. This dissertation proposes three kinds of olfactory-based navigation methods to improve search efficiency while maintaining a low computational cost, incorporating different machine learning and artificial intelligence methods.

A. …


Helical Dielectric Elastomer Actuator, Daewon Kim Aug 2021

Helical Dielectric Elastomer Actuator, Daewon Kim

Publications

A helical dielectric elastomer actuator (HDEA) can include a first dielectric region comprising an elastomer defining a helix. In an example, a dielectric material can be deposited, and a compliant conductive material can be deposited, such as using an additive manufacturing approach, to provide an HDEA. In an example where the HDEA has multiple mechanical degrees of freedom, at least two compliant conductive regions can be located on a first surface of the first dielectric region and at least one compliant conductive region can be located on an opposite second surface of the first dielectric region. For such an example, …


Dynamic Task Allocation In Partially Defined Environments Using A* With Bounded Costs, James Hendrickson May 2021

Dynamic Task Allocation In Partially Defined Environments Using A* With Bounded Costs, James Hendrickson

Doctoral Dissertations and Master's Theses

The sector of maritime robotics has seen a boom in operations in areas such as surveying and mapping, clean-up, inspections, search and rescue, law enforcement, and national defense. As this sector has continued to grow, there has been an increased need for single unmanned systems to be able to undertake more complex and greater numbers of tasks. As the maritime domain can be particularly difficult for autonomous vehicles to operate in due to the partially defined nature of the environment, it is crucial that a method exists which is capable of dynamically accomplishing tasks within this operational domain. By considering …


A Comprehensive Mapping And Real-World Evaluation Of Multi-Object Tracking On Automated Vehicles, Alexander Bassett Apr 2021

A Comprehensive Mapping And Real-World Evaluation Of Multi-Object Tracking On Automated Vehicles, Alexander Bassett

Doctoral Dissertations and Master's Theses

Multi-Object Tracking (MOT) is a field critical to Automated Vehicle (AV) perception systems. However, it is large, complex, spans research fields, and lacks resources for integration with real sensors and implementation on AVs. Factors such those make it difficult for new researchers and practitioners to enter the field.

This thesis presents two main contributions: 1) a comprehensive mapping for the field of Multi-Object Trackers (MOTs) with a specific focus towards Automated Vehicles (AVs) and 2) a real-world evaluation of an MOT developed and tuned using COTS (Commercial Off-The-Shelf) software toolsets. The first contribution aims to give a comprehensive overview of …


Finite-Time State Estimation For An Inverted Pendulum Under Input-Multiplicative Uncertainty, Sergey V. Drakunov, William Mackunis, Anu Kossery Jayaprakash, Krishna Bhavithavya Kidambi, Mahmut Reyhanoglu Oct 2020

Finite-Time State Estimation For An Inverted Pendulum Under Input-Multiplicative Uncertainty, Sergey V. Drakunov, William Mackunis, Anu Kossery Jayaprakash, Krishna Bhavithavya Kidambi, Mahmut Reyhanoglu

Publications

A sliding mode observer is presented, which is rigorously proven to achieve finite-time state estimation of a dual-parallel underactuated (i.e., single-input multi-output) cart inverted pendulum system in the presence of parametric uncertainty. A salient feature of the proposed sliding mode observer design is that a rigorous analysis is provided, which proves finite-time estimation of the complete system state in the presence of input-multiplicative parametric uncertainty. The performance of the proposed observer design is demonstrated through numerical case studies using both sliding mode control (SMC)- and linear quadratic regulator (LQR)-based closed-loop control systems. The main contribution presented here is the rigorous …


Vex U Robotics, Kyle Lutterman, Jeffrey Ryan, Sierra Wong, Elizabeth Geiger Apr 2020

Vex U Robotics, Kyle Lutterman, Jeffrey Ryan, Sierra Wong, Elizabeth Geiger

Discovery Day - Prescott

VEX U is a competition hosted by the REC Foundation for university students to get engaged in hands-on engineering. Each team produces two robots using the VEX provided parts to compete in the VEX U competition. The competition changes every year with the only constants being the size of the field, the tools and parts teams are able to use, and the size constraints of the robots. The teams compete in regional competitions in order to qualify for the World Championship Competition, which is the highest competition a team can compete in for VEX U. The VEX U teams at …


Tech Comm Eagle Eye-Tracking Control System, Gabiella Lail, Robert Shaw, Hunter Smatla, Matthew Gary Apr 2020

Tech Comm Eagle Eye-Tracking Control System, Gabiella Lail, Robert Shaw, Hunter Smatla, Matthew Gary

Discovery Day - Prescott

Mobile eye-tracking systems provide usability research support as well as access to a wide range of robotics and technical communication research opportunities. Optical tracking systems are often prohibitively expensive and do not provide the mobility or flexibility needed for a variety of research application possibilities. Our team proposes building a simple mobile eye-tracking system to be used in-house at ERAU for heat-mapping, robotics, control systems, and various technical communication applications in a structured research environment. The mobile eyetracking system will become part of a larger research and hands-on technical communication usability lab and research center. The research team intends to …


Validation Framework For Autonomous Aerial Vehicles, Mustafa Akbas Ph.D. Mar 2020

Validation Framework For Autonomous Aerial Vehicles, Mustafa Akbas Ph.D.

National Training Aircraft Symposium (NTAS)

Autonomous aerial vehicles (AAV) have the potential to have market disruptions for various industries such as ground delivery and aerial transportation. Hence, the USAF has called for increased level of autonomy and rapid progress is being made in artificial intelligence (AI) engines, complex and non-deterministic system components, which are at the core of the autonomous aerial platforms. Traditional testing and validation methods fall short of satisfying the requirement of testing such complex systems. Therefore, to achieve highly or fully autonomous capabilities, a major leap forward in the validation is required. Otherwise, the full capabilities of autonomy will not be realized. …


Advanced Inflatable De-Orbit Solutions For Derelict Satellites And Orbital Debris, Aman Chandra, Greg Wilburn, Jekan Thanga Feb 2019

Advanced Inflatable De-Orbit Solutions For Derelict Satellites And Orbital Debris, Aman Chandra, Greg Wilburn, Jekan Thanga

Space Traffic Management Conference

The exponential rise in small-satellites and CubeSats in Low Earth Orbit (LEO) poses important challenges for future space traffic management. At altitudes of 600 km and lower, aerodynamic drag accelerates de-orbiting of satellites. However, placement of satellites at higher altitudes required for constellations pose important challenges. The satellites will require on-board propulsion to lower their orbits to 600 km and let aerodynamic drag take-over. In this work we analyze solutions for de-orbiting satellites at altitudes of up to 3000 km. We consider a modular robotic de-orbit device that has stowed volume of a regular CubeSat. The de-orbit device would be …


End To End Satellite Servicing And Space Debris Management, Aman Chandra, Himangshu Kalita, Roberto Furfaro, Jekan Thanga Feb 2019

End To End Satellite Servicing And Space Debris Management, Aman Chandra, Himangshu Kalita, Roberto Furfaro, Jekan Thanga

Space Traffic Management Conference

There is growing demand for satellite swarms and constellations for global positioning, remote sensing and relay communication in higher LEO orbits. This will result in many obsolete, damaged and abandoned satellites that will remain on-orbit beyond 25 years. These abandoned satellites and space debris maybe economically valuable orbital real-estate and resources that can be reused, repaired or upgraded for future use. Space traffic management is critical to repair damaged satellites, divert satellites into warehouse orbits and effectively deorbit satellites and space debris that are beyond repair and salvage. Current methods for on-orbit capture, servicing and repair require a large service …


Evaluation Of Suas Education And Training Tools, Brent Terwilliger, Scott Burgess, James Solti, Kristine Kiernan, Christian Janke, Andrew Shepherd Jan 2019

Evaluation Of Suas Education And Training Tools, Brent Terwilliger, Scott Burgess, James Solti, Kristine Kiernan, Christian Janke, Andrew Shepherd

Publications

The wide distribution and demographic composition of students seeking small unmanned aircraft system (sUAS) education presents a need to fully understand the capabilities, limitations, and dependencies of effective training tools. Concepts, practices, and technologies associated with modeling and simulation, immersive gaming, augmented and mixed-reality, and remote operation have demonstrated efficacy to support engaged student learning and objective satisfaction. Identification and comparison of key attributes critical to an aviation educational framework, such as competency-based training, enables educational designers to identify those tools with the highest potential to support successful learning. A series of factors, such as system performance, regulatory compliance, environmental …


Big Five Technologies In Aeronautical Engineering Education: Scoping Review, Ruth Martinez-Lopez Jan 2019

Big Five Technologies In Aeronautical Engineering Education: Scoping Review, Ruth Martinez-Lopez

International Journal of Aviation, Aeronautics, and Aerospace

The constant demands that technology creates in aerospace engineering also influence education. The identification of the technologies with practical application in aerospace engineering is of current interest to decision makers in both universities and industry. A social network approach enhances this scoping review of the research literature to identify the main topics using the Big Five technologies in aerospace engineering education. The conceptual structure of the dataset (n=447) was analyzed from different approaches: at macro-level, a comparative of the digital technology identified by cluster analysis with the number of co-words established in 3 and 8 and, a keyword central structure …


Project Janus, Theodore J. Lilyeblade, Jacqueline Worley, Garrison Bybee Oct 2018

Project Janus, Theodore J. Lilyeblade, Jacqueline Worley, Garrison Bybee

Undergraduate Research Symposium - Prescott

The development goal of Project Janus is to design, fabricate, and program two robotic heads that can serve as animatronic chatbots. Each robotic head will be equipped with two USB webcams, a mono speaker within the robot’s mouth, and a pair of microphones. Additionally, each robotic head will feature a three degree of freedom neck, a one degree-of-freedom jaw, and a two degree-of-freedom gimbal for the eyes upon which the cameras will be mounted. The robotic heads will be interfaced to separate internet connected personal computers. Through these computers, they will make use of online speech recognition tools, online chatbots, …


Surgical And Medical Applications Of Drones: A Comprehensive Review, Brent Terwilliger, James C. Rosser Jr., Vudatha Vignesh, Brett C. Parker Jul 2018

Surgical And Medical Applications Of Drones: A Comprehensive Review, Brent Terwilliger, James C. Rosser Jr., Vudatha Vignesh, Brett C. Parker

Publications

Drones have the ability to gather real time data cost effectively, to deliver payloads and have initiated the rapid evolution of many industrial, commercial, and recreational applications. Unfortunately, there has been a slower expansion in the field of medicine. This article provides a comprehensive review of current and future drone applications in medicine, in hopes of empowering and inspiring more aggressive investigation.


Magic Triangle – Human, Exoskeleton, And Collaborative Robot Scenario, R. A. Goehlich, M. H. Rutsch, I. Krohne Jan 2018

Magic Triangle – Human, Exoskeleton, And Collaborative Robot Scenario, R. A. Goehlich, M. H. Rutsch, I. Krohne

Publications

The incidence of musculoskeletal disorders in workplaces with difficult ergonomic conditions is increasing. Today, there is a growing market for technical support systems that avoid repetitive strain on the musculoskeletal system. We have been observing two (parallel) lines of development: on the one hand, the development of exoskeletons supporting shop floor operators and, on the other hand, the development of collaborative robots for the creation of hybrid teams. The focus of our research is the combined application of exoskeletons AND collaborative robots for shop floor operators in the aerospace industry. Our approach is to analyze various scenarios to understand which …


Nonlinear Control For Dual Quaternion Systems, William D. Price Jan 2013

Nonlinear Control For Dual Quaternion Systems, William D. Price

Doctoral Dissertations and Master's Theses

The motion of rigid bodies includes three degrees of freedom (DOF) for rotation, generally referred to as roll, pitch and yaw, and 3 DOF for translation, generally described as motion along the x, y and z axis, for a total of 6 DOF. Many complex mechanical systems exhibit this type of motion, with constraints, such as complex humanoid robotic systems, multiple ground vehicles, unmanned aerial vehicles (UAVs), multiple spacecraft vehicles, and even quantum mechanical systems. These motions historically have been analyzed independently, with separate control algorithms being developed for rotation and translation. The goal of this research is to study …


Dynamics And Control Of Higher-Order Nonholonomic Systems, Jaime Rubio HerváS Jan 2013

Dynamics And Control Of Higher-Order Nonholonomic Systems, Jaime Rubio HerváS

Doctoral Dissertations and Master's Theses

A theoretical framework is established for the control of higher-order nonholonomic systems, defined as systems that satisfy higher-order nonintegrable constraints. A model for such systems is developed in terms of differential-algebraic equations defined on a higher-order tangent bundle. A number of control-theoretic properties such as nonintegrability, controllability, and stabilizability are presented. Higher-order nonholonomic systems are shown to be strongly accessible and, under certain conditions, small time locally controllable at any equilibrium. There are important examples of higher-order nonholonomic systems that are asymptotically stabilizable via smooth feedback, including space vehicles with multiple slosh modes and Prismatic-Prismatic-Revolute (PPR) robots moving open liquid …


Effects Of Visual Interaction Methods On Simulated Unmanned Aircraft Operator Situational Awareness, Brent A. Terwilliger Jan 2012

Effects Of Visual Interaction Methods On Simulated Unmanned Aircraft Operator Situational Awareness, Brent A. Terwilliger

Publications

The limited field of view of static egocentric visual displays employed in unmanned aircraft controls introduces the soda straw effect on operators, which significantly affects their ability to capture and maintain situational awareness by not depicting peripheral visual data. The problem with insufficient operator situational awareness is the resulting increased potential for error and oversight during operation of unmanned aircraft, leading to accidents and mishaps costing United States taxpayers between $4 million to $54 million per year. The purpose of this quantitative experimental completely randomized design study was to examine and compare use of dynamic eyepoint to static visual interaction …


Trends. War On Personality And Personality And War: Comments On Nass And Lee (2002), Ibpp Editor Sep 2002

Trends. War On Personality And Personality And War: Comments On Nass And Lee (2002), Ibpp Editor

International Bulletin of Political Psychology

This Trends article discusses another article – Identity and deconstruction, by Clifford Nass and Kwan Min Yee – published in volume 3 (2002) of Archives of Psychiatry & Psychotherapy in which the authors demonstrate that people reliably attribute personality characteristics to computer-synthesized speech, exploring the ramifications in a political psychological context.