Cody Fleming

Cody Fleming
Iowa State University | ISU · Department of Mechanical Engineering

Doctor of Philosophy

About

83
Publications
20,008
Reads
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645
Citations
Introduction
Cody Fleming currently works in the Department of Mechanical Engineering at Iowa State University. Previously he was in the Department of Engineering Systems and Environment, and Mechanical and Aerospace Engineering, both at the University of Virginia. Cody does research in Control Systems Engineering, Aerospace Engineering and Engineering Systems. He has several current projects, including 'Cooperative Traffic Management' and 'Safety Assurance of Air Traffic Management Systems'.
Additional affiliations
August 2020 - present
Iowa State University
Position
  • Professor (Associate)
Description
  • Research, Education, Service
August 2020 - present
University of Virginia
Position
  • Professor
August 2015 - August 2020
University of Virginia
Position
  • Professor (Assistant)
Education
September 2010 - January 2015
Massachusetts Institute of Technology
Field of study
  • Aeronautics and Astronautics

Publications

Publications (83)
Article
Our work focuses on modeling the security of systems from their component-level designs. Towards this goal, we develop a categorical formalism to model attacker actions. Equipping the categorical formalism with algebras produces two interesting results for security modeling. First, using the Yoneda lemma, we can model attacker reconnaissance missio...
Preprint
Full-text available
With the rapid advancement of Formal Methods, Model-based Safety Analysis (MBSA) has been gaining tremendous attention for its ability to rigorously verify whether the safety-critical scenarios are adequately addressed by the design solution of a cyber-physical human system. However, there is a gap. If specific safety-critical scenarios are not inc...
Article
Infrastructure damage has household‐level consequences after a major disaster. Losses are experienced due to factors such as unavailable services and impaired mobility. Socially vulnerable residents, in particular, have few resources with which to adapt. Decision support tools for making justifiable, transparent, repeatable decisions that center th...
Article
Full-text available
Cyber-physical systems are complex systems that require the integration of diverse software, firmware, and hardware to be practical and useful. This increased complexity is impacting the management of models necessary for designing cyber-physical systems that are able to take into account a number of “-ilities”, such that they are safe and secure a...
Article
Full-text available
Engineering safe and secure cyberphysical systems requires system engineers to develop and maintain a number of model views, both dynamic and static. Verifying the composition of requirement, behavioral, and architectural models using category theory gives rise to a strictly compositional interpretation of cyberphysical systems theory.
Article
This work presents DMPC (Data-and Model-Driven Predictive Control) to solve control problems in which some of the constraints or parts of the objective function are known, while others are entirely unknown to the controller. It is assumed that there is an exogenous “black box” system, e.g. a machine learning technique, that predicts the value of th...
Article
Full-text available
Cyber-physical systems require the construction and management of various models to assure their correct, safe, and secure operation. These various models are necessary because of the coupled physical and computational dynamics present in cyber-physical systems. However, to date the different model views of cyber-physical systems are largely relate...
Preprint
Full-text available
In this paper, we present a data-driven Model Predictive Controller that leverages a Gaussian Process to generate optimal motion policies for connected autonomous vehicles in regions with uncertainty in the wireless channel. The communication channel between the vehicles of a platoon can be easily influenced by numerous factors, e.g. the surroundin...
Article
Full-text available
Cyberphysical systems require resiliency techniques for defense, and multicriteria resiliency problems need an approach that evaluates systems for current threats and potential design solutions. A systems-oriented view of cyberphysical security, termed Mission Aware, is proposed based on a holistic understanding of mission goals, system dynamics, a...
Preprint
Engineering safe and secure cyber-physical systems requires system engineers to develop and maintain a number of model views, both dynamic and static, which can be seen as algebras. We posit that verifying the composition of requirement, behavioral, and architectural models using category theory gives rise to a strictly compositional interpretation...
Technical Report
Model-based safety analysis (MBSA) has been around for over two decades. The benefits of MBSA have been well-documented in the literature, such as tackling complexity, introducing Formal Methods to eliminate the ambiguity in the traditional safety analysis, using automation to replace the error-prone manual safety modeling process, and ensuring con...
Preprint
Full-text available
This work presents DMPC (Data-and Model-Driven Predictive Control) to solve control problems in which some of the constraints or parts of the objective function are known, while others are entirely unknown to the controller. It is assumed that there is an exogenous ``black box'' system, e.g. a machine learning technique, that predicts the value of...
Preprint
Full-text available
Our work focuses on modeling security of systems from their component-level designs. Towards this goal we develop a categorical formalism to model attacker actions. Equipping the categorical formalism with algebras produces two interesting results for security modeling. First, using the Yoneda lemma, we are able to model attacker reconnaissance mis...
Preprint
Full-text available
Safe navigation of autonomous agents in human centric environments requires the ability to understand and predict motion of neighboring pedestrians. However, predicting pedestrian intent is a complex problem. Pedestrian motion is governed by complex social navigation norms, is dependent on neighbors' trajectories, and is multimodal in nature. In th...
Preprint
Full-text available
Assuring the correct behavior of cyber-physical systems requires significant modeling effort, particularly during early stages of the engineering and design process when a system is not yet available for testing or verification of proper behavior. A primary motivation for `getting things right' in these early design stages is that altering the desi...
Article
Full-text available
Assuring the correct behavior of cyber-physical systems requires significant modeling effort, particularly during early stages of the engineering and design process when a system is not yet available for testing or verification of proper behavior. A primary motivation for `getting things right' in these early design stages is that altering the desi...
Conference Paper
This paper seeks to integrate two major facets of a next-generation air transportation management system: interval management (specifically flight-deck interval management) and trajectory-based operations. Interval management is the concept of delegating spacing between aircraft to increase utilization of airspace. However, an improvement on curren...
Article
Cyber Physical Systems (CPS) is an emerging field in its own right. Education for CPS is beginning to emerge, but is often only taught via one or two classes, or by collecting currently offered classes. This paper describes a complete graduate curriculum for CPS that consists of teaching core classes, in-depth classes, and professional development...
Preprint
Full-text available
Cyber-physical systems (CPS) are often defended in the same manner as information technology (IT) systems -- by using perimeter security. Multiple factors make such defenses insufficient for CPS. Resiliency shows potential in overcoming these shortfalls. Techniques for achieving resilience exist; however, methods and theory for evaluating resilienc...
Preprint
Full-text available
Cyber-physical systems require the construction and management of various models to assure their correct, safe, and secure operation. These various models are necessary because of the coupled physical and computational dynamics present in cyber-physical systems. However, to date the different model views of cyber-physical systems are largely relate...
Conference Paper
Full-text available
Assuring the correct behavior of cyber-physical systems requires significant modeling effort, particularly during early stages of the engineering and design process when a system is not yet available for testing or verification of proper behavior. A primary motivation for 'getting things right' in these early design stages is that altering the desi...
Preprint
Full-text available
In this paper, we consider the problem of creating a safe-by-design Rectified Linear Unit (ReLU) Neural Network (NN), which, when composed with an arbitrary control NN, makes the composition provably safe. In particular, we propose an algorithm to synthesize such NN filters that safely correct control inputs generated for the continuous-time Kinema...
Preprint
Full-text available
System complexity has become ubiquitous in the design, assessment, and implementation of practical and useful cyber-physical systems. This increased complexity is impacting the management of models necessary for designing cyber-physical systems that are able to take into account a number of ``-ilities'', such that they are safe and secure and ultim...
Preprint
Full-text available
Systems modeling practice lacks security analysis tools that can interface with modeling languages to facilitate security by design. Security by design is a necessity in the age of safety critical cyber-physical systems, where security violations can cause hazards. Currently, the overlap between security and safety is narrow. But deploying cyber-ph...
Conference Paper
Flight-deck Interval Management (FIM) is a concept that increases safety and efficiency by effectively managing spacing between aircraft. Current FIM uses speed adjustment to achieve and maintain a desired spacing. Studies show it is promising to increase the overall air traffic throughput compared with current operation. However, the precise spaci...
Preprint
Full-text available
Ships, or vessels, often sail in and out of cluttered environments over the course of their trajectories. Safe navigation in such cluttered scenarios requires an accurate estimation of the intent of neighboring vessels and their effect on the self and vice-versa well into the future. In manned vessels, this is achieved by constant communication bet...
Article
Full-text available
Multiyear population displacement is a feature of natural disasters that have caused widespread infrastructure damage. This interdisciplinary, transportation-centric survey paper offers guidelines for civil infrastructure system (CIS) models supporting recovery managers and transportation system managers who are seeking to reduce displacement durat...
Article
Full-text available
Applying security as a lifecycle practice is becoming increasingly important to combat targeted attacks in safety-critical systems. Among others, there are two significant challenges in this area: the need for models that can characterize a realistic system in the absence of an implementation and an automated way to associate attack vector informat...
Preprint
Full-text available
Applying security as a lifecycle practice is becoming increasingly important to combat targeted attacks in safety-critical systems. Among others there are two significant challenges in this area: (1) the need for models that can characterize a realistic system in the absence of an implementation and (2) an automated way to associate attack vector i...
Preprint
Full-text available
Requirement decomposition is a widely accepted Systems Engineering practice for Requirements Engineering. Getting the requirements correct at the very beginning of the lifecycle is crucial for the success of engineering a correct system. This is especially the case for safety-critical complex systems, where incorrect or clashing requirements can le...
Article
Globally, risk factors for population displacement due to major disasters are on the rise. These factors include the increasing frequency of extreme weather events, aging infrastructure, growing populations, and increasing urbanization. In cases of widespread damage, tools are needed to support complicated multiyear reconstruction efforts so that p...
Conference Paper
Full-text available
A Learning Model Predictive Controller (LMPC) is presented and tailored to platooning and Connected Autonomous Vehicles (CAVs) applications. The proposed controller builds on previous work on nonlinear LMPC, adapting its architecture and extending its capability to (a) handle dynamic environments and (b) account for data-driven decision variables t...
Preprint
Full-text available
A Learning Model Predictive Controller (LMPC) is presented and tailored to platooning and Connected Autonomous Vehicles (CAVs) applications. The proposed controller builds on previous work on nonlinear LMPC, adapting its architecture and extending its capability to (a) handle dynamic environments and (b) account for data-driven decision variables t...
Article
Cyber‐physical systems (CPS) present a unique modeling challenge due to their numerous heterogeneous components, complex physical interactions, and disjoint communication networks. Modeling CPS to aid security analysis further adds to these challenges, because securing CPS requires not only understanding of the system architecture, but also the sys...
Preprint
Full-text available
Petroleum industry is the world's biggest energy source, and its associated industries such as production, distribution, refining and retail are considered as the largest ones in the world. Having the increasing price and governments job creation and international environmental policies, the petroleum companies try to maximize the number of created...
Conference Paper
Full-text available
Time-based Flow Management (TBFM) is one of the core portfolios of the Next Generation Air Transportation System (NextGen). However, according to multiple reports, there is general confusion about the usage and implementation of the time- based capabilities. This paper aims at answering questions about the usage of time-based instructions and speed...
Conference Paper
The performance of autonomous cars can be greatly enhanced through wireless coordination. However, mobility has traditionally been a challenge for wireless networks due to rapid fluctuation of the signal quality. Current control systems handle this challenge by slowing down the vehicle to preserve safety. However, in this research, we demonstrate t...
Article
Full-text available
Despite “cyber” being in the name, cyber–physical systems possess unique characteristics that limit the applicability and suitability of traditional cybersecurity techniques and strategies. Furthermore, vulnerabilities to cyber–physical systems can have significant safety implications. The physical and cyber interactions inherent in these systems r...
Article
This paper systematically investigates the safety implications of a new 4-dimensional air traffic management paradigm by quantitatively identifying conditions where conflict-free trajectories can be guaranteed by only using 4-dimensional waypoints. Towards this end, a concept called Trajectory Inclusion is first introduced based on geometry and phy...
Preprint
Full-text available
The growing use of deep neural networks in safety-critical applications makes it necessary to carry out adequate testing to detect and correct any incorrect behavior for corner case inputs before they can be actually used. Deep neural networks lack an explicit control-flow structure, making it impossible to apply to them traditional software testin...
Preprint
Full-text available
With the emergence of autonomous ground vehicles and the recent advancements in Intelligent Transportation Systems, Autonomous Traffic Management has garnered more and more attention. Autonomous Intersection Management (AIM), also known as Cooperative Intersection Management (CIM) is among the more challenging traffic problems that poses important...
Article
Full-text available
A novel, exact algorithm is presented to solve the path planning problem that involves finding the shortest collision-free path from a start to a goal point in a two-dimensional environment containing convex and non-convex obstacles. The proposed algorithm, which is called the shortest possible path (SPP) algorithm, constructs a network of lines co...
Preprint
Full-text available
Today, there is a plethora of software security tools employing visualizations that enable the creation of useful and effective interactive security analyst dashboards. Such dashboards can assist the analyst to understand the data at hand and, consequently, to conceive more targeted preemption and mitigation security strategies. Despite the recent...
Article
Full-text available
Currently, perimeter-based approaches are the mainstay of cybersecurity. While this paradigm is necessary, there is mounting evidence of its insufficiency with respect to sophisticated and coordinated attacks. In contrast to perimeter-based security, mission-centric cybersecurity provides awareness of how attacks can influence mission success and t...
Article
Full-text available
The security of cyber-physical systems is first and foremost a safety problem, yet it is typically handled as a traditional security problem, which means that solutions are based on defending against threats and are often implemented too late. This approach neglects to take into consideration the context in which the system is intended to operate,...
Article
Evaluating the security of cyber-physical systems throughout their life cycle is necessary to assure that they can be deployed and operated in safety-critical applications, such as infrastructure, military, and transportation. Most safety and security decisions that can have major effects on mitigation strategy options after deployment are made ear...
Article
Full-text available
Systems thinking characterizes the paradigm needed to effectively design, maintain, and utilize systems. Prior work has shown that there is a language of systems thinking and that its presence can be quantified within text using supervised learning methods. Building on this foundation, we present a human-in-the-loop methodology that utilizes topic...
Article
As transportation systems become increasingly complex and the roles of human operators and autonomous software continue to evolve, traditional safety-related analytical methods are becoming inadequate. Traditional hazard analysis tools are based on an accident causality model that does not capture many of the complex behaviors found in modern engin...
Article
Safety should be designed into systems from their very conception, which can be achieved by integrating powerful hazard analysis techniques into the general systems engineering process. The primary barrier to achieving this objective is the lack of effectiveness of the existing analytical tools during early concept development. This paper introduce...
Conference Paper
Safety should be designed into systems from their very conception, which can be achieved by integrating powerful hazard analysis techniques into the general systems engineering process. The primary barrier to achieving this objective is the lack of effectiveness of the existing analytical tools during early concept development. This paper introduce...