This study focuses on conducting a benchmarking analysis for light wheeled and tracked robotic vehicles. Vehicle mobility has long been a key aspect of research for many organizations. According to the Department of Defense vehicle mobility is defined as, "the overall capacity to move from place to place while retaining its ability to perform its primary mission"[1]. Until recently this definition has been applied exclusively to large scale wheeled and tracked vehicles. With new development lightweight ground vehicles designed for military and space exploration applications, the meaning of vehicle mobility must be revised and the tools at our disposal for evaluating mobility must also be expanded. In this context a significant gap in research is present and the main goal of this thesis is to help fill the void in knowledge regarding small robotic vehicle mobility assessment. Another important aspect of any vehicle is energy efficiency. Thus, another aim of this study is to compare the energy needs for a wheeled versus tracked robot, while performing similar tasks. The first stage of the research is a comprehensive review of the state-of-the-art in vehicle mobility assessment. From this review, a mobility assessment criterion for light robots will be developed. The second stage will be outfitting a light robotic vehicle with a sensor suite capable of capturing relevant mobility criteria. The third stage of this study will be an experimental investigation of the mobility capability of the vehicle. Finally the fourth stage will include quantitative and qualitative evaluation of the benchmarking study. / Master of Science

Στόχος της παρούσας διπλωματικής εργασίας είναι η μελέτη και η ανάπτυξη ενός ρομποτικού οχήματος το οποίο θα είναι ικανό να πλοηγηθεί αυτόνομα στο χώρο αναγνωρίζοντας και αποφεύγοντας τα πιθανά εμπόδια στο περιβάλλον που θα κινηθεί. / The aim of this thesis is to study and develop a robotic vehicle that will be able to navigate autonomously in space by identifying and avoiding potential barriers in the environment that it will move.

No description available.

Networked control systems (NCSs) are feedback control systems with the feedback control loops closed via network. The origin of the term NCSs is from industrial systems where the plant and controller are often connected through networks. The applications of NCSs cover a wide range of industries, for example, manufactory automation, domestic robots, aircraft, automobiles and tele-operations. The research activities in NCSs are focused on the following three areas: control of networks, control over networks and multi-agent systems. Control of networks is mainly concerned with the problem of how to efficiently utilize the network resource by controlling and routing the network data flows. Control over networks is mainly concerned with the design of feedback control strategies of control systems in which signals are transmitted through unreliable communication links. Multi-agent systems deal with two problems: how the topology of the network connections between each component influences global control goals and how to design local control law describing the behavior of each individual to achieve the global control goal of the whole systems. The objective in this thesis is to deal with control over networks and multi-agent systems. The most challenging problem in the control over networks field is that the unreliable communication channels can degrade system performance greatly. The main unreliable properties of networks are delays and packet loss. In order to deal with this problem, a Lyapunov-based method has been used to design the sampled-data stabilization control strategy for a networked single system by choosing proper delay and packet loss dependent Lyapunov functional candidates. Linear matrix inequality techniques have been used to find the sufficient and necessary conditions for the controller design. Furthermore, the consensus formation control problem of multiple robotic vehicle systems has been investigated. The consensus-based design scheme has been applied to the formation control of multiple wheeled mobile-robot group with a virtual leader. A novel delay-dependent Lyapunov functional candidate has been constructed to investigate the convergence of the system states. The proposed control strategy is experimentally implemented for multiple wheeled mobile robots under neighbor-to-neighbor information exchange with group communication delays involved. In conclusion, through the simulation results and experimental validations, the proposed new Lyapunov-based control methods can effectively deal with the networked control systems discussed in this thesis.

This thesis is concerned with an experimental platform for studying cooperative driving and techniques for embedded systems programming. Cooperative driving systems use vehicle-to-vehicle and vehicle-to-infrastructure communication for safe, smooth and efficient transportation. Cooperative driving systems are considered as a promising solution for traffic situations such as blind crossings. For the thesis work we use a robotic vehicle known as PIE (Platform for Intelligent Embedded Systems) equipped with a wireless communication device, electrical motors and controlled via a SAM7-P256 development board. For the infrastructure side we use a SAM7-P256 development board equipped with nRF24l01. Vehicle to vehicle and base station to vehicle communication is established and different platooning scenarios are implemented. The scenarios are similar to platooning scenarios from the Grand Cooperative Driving Challenge GCDC1. The performance of the platoon control algorithm is measured in terms of throughput (a measure of string stability), smoothness and safety, where the safety requirements serve as pass/fail criteria.

Recent advances in technology have enabled the development of truly autonomous ground vehicles capable of performing complex navigation tasks. As a result, the demand for practical unmanned ground vehicle (UGV) systems has increased dramatically in recent years. Central to these developments is maturation of emerging mobile robotic intelligent and autonomous capability. While the progress UGV technology has been substantial, there are many challenges that still face unmanned vehicle system developers. Foremost is the improvement of perception hardware and intelligent software that supports the evolution of UGV capability. The development of a Next-generation Experimentation Robotic Vehicle (NERV) serves to provide a small UGV baseline platform supporting experimentation focused on progression of the state-of-the-art in unmanned systems. Supporting research and user feedback highlight the needs that provide justification for an advanced small UGV research platform. Primarily, such a vehicle must be based upon open and technology independent system architecture while exhibiting improved mobility over relatively structured terrain. To this end, a theoretical kinematic model is presented for a novel two-body multi degree-of-freedom, four-wheel drive, small UGV platform. The efficacy of the theoretical kinematic model was validated through computer simulation and experimentation on a full-scale proof-of-concept mobile robotic platform. The kinematic model provides the foundation for autonomous multi-body control. Further, a modular system level design based upon the concepts of the Joint Architecture for Unmanned Systems (JAUS) is offered as an open architecture model providing a scalable system integration solution. Together these elements provide a blueprint for the development of a small UGV capable of supporting the needs of a wide range of leading-edge intelligent system research initiatives. / Master of Science

<p>This thesis is concerned with an experimental platform for studying cooperative driving and techniques for embedded systems programming. Cooperative driving systems use vehicle-to-vehicle and vehicle-to-infrastructure communication for safe, smooth and efficient transportation. Cooperative driving systems are considered as a promising solution for traffic situations such as blind crossings. For the thesis work we use a robotic vehicle known as PIE (Platform for Intelligent Embedded Systems) equipped with a wireless communication device, electrical motors and controlled via a SAM7-P256 development board. For the infrastructure side we use a SAM7-P256 development board equipped with nRF24l01. Vehicle to vehicle and base station to vehicle communication is established and different platooning scenarios are implemented. The scenarios are similar to platooning scenarios from the Grand Cooperative Driving Challenge GCDC1. The performance of the platoon control algorithm is measured in terms of throughput (a measure of string stability), smoothness and safety, where the safety requirements serve as pass/fail criteria.</p>

<p dir="ltr">The world is increasingly dependent on cyber-physical systems (CPSs), e.g., robotic vehicles (RVs) and industrial control systems (ICSs). CPSs operate autonomously by processing data coming from both “cyberspace”—such as user commands—and “physical space”—such as sensors that measure the physical environment in which they operate. However, even after decades of research, CPSs remain susceptible to threats from attackers, primarily due to the increased complexity created by interaction with cyber and physical space (e.g., the cascading effects that changes in one space can impact on the other). In particular, the complexity causes two primary threats that increase the risk of causing physical damage to RVs: (1) logic bugs causing undesired physical behavior from the developers expectations; and (2) physical sensor attacks—such as GPS or acoustic noise spoofing—that disturb an RV’s sensor readings. Dealing with these threats requires addressing the interplay between cyber and physical space. In this dissertation, we systematically analyze the interplay between cyber and physical space, thereby tackling security problems created by such complexity. We present novel algorithms to detect logic bugs (PGFuzz in Chapter 2), help developers fix them (PGPatch in Chapter 3), and test the correctness of the patches attempting to address them (PatchVerif in Chapter 4). Further, we explain algorithms to discover the root causes and formulate countermeasures against physical sensor attacks that target RVs in Chapter 5.</p>

<p>Cyber-Physical Systems (CPS) are integrated systems that consist of the computational and physical components with network communication to support operation in the physical world. My PhD dissertation focuses on the security and reliability of autonomous cyber-physical systems, such as self-driving cars, drones, and underwater robots, that are safety-critical systems based on the seamless integration of cyber and physical components. Autonomous CPS are becoming an integral part of our life. The market for autonomous driving systems is expected to be more than $65 billion by 2026. The security of such CPS is hence critical. Beyond traditional cyber-only computing systems, these complex and integrated CPS have unique characteristics. From the security perspective, they open unique research opportunities since they introduce additional attack vectors and post new challenges that existing cyber-oriented approaches cannot address well. <em>The goal of my research is to build secure and reliable autonomous CPS by bridging the gap between the cyber and physical domains.</em> To this end, my work focuses on fundamental research questions associated with cyber-physical attack and defense, vulnerability discovery and elimination, and post-attack investigation. My approach to solving the problems involves various techniques and interdis- ciplinary knowledge, including program analysis, search-based software engineering, control theory, robotics, and AI/machine learning.</p>

<p dir="ltr">This paper aims to gain a deep understanding of up-to-date research and development on modular self-reconfigurable robots (MSRs) through a thorough survey of market demands and published works on <i>design methodologies</i>, <i>system integration</i>, <i>advanced controls</i>, and <i>new applications</i>. Some limitations of existing mobile MSR are discussed from the reconfigurability perspective of mechanical structures, and a novel MSR system is proposed to address the identified limitations of existing MSRs. The comprehensive set of <i>Functional Requirements</i> (FRs) of MSRs is discussed, from which the mechanical designs of MSR were created, and the system was prototyped and built for testing. Three main innovations of the designed modules for MSR are to (1) share torque power, (2) customize the size for a given task, and (3) have a low number of actuated motors while still maintain a motion with high <i>Degrees of Freedom</i> (DoF) to overcome the constraints by the power capacities of individual motors; this helps to increase reconfigurability, reduce cost, and reduce the size of conventional MSRs.</p>