Acumen : an open-source testbed for cyber-physical systems research

Developing Cyber-Physical Systems requires methods and tools to support simulation and verification of hybrid (both continuous and discrete) models. The Acumen modeling and simulation language is an open source testbed for exploring the design space of what rigorousbut- practical next-generation tools can deliver to developers of Cyber- Physical Systems. Like verification tools, a design goal for Acumen is to provide rigorous results. Like simulation tools, it aims to be intuitive, practical, and scalable. However, it is far from evident whether these two goals can be achieved simultaneously. This paper explains the primary design goals for Acumen, the core challenges that must be addressed in order to achieve these goals, the “agile research method” taken by the project, the steps taken to realize these goals, the key lessons learned, and the emerging language design

Advancements in Hardware-Enabled Cyber-Physical Systems: A Comprehensive Exploration in Electronics and Computer Science.

The rapid evolution of Hardware-Enabled Cyber-Physical Systems (HE-CPS) plays a pivotal role in reshaping the landscape of Electronics and Computer Science. This research delves into recent breakthroughs, aiming to elucidate the integration of state-of-the-art hardware, artificial intelligence (AI), and machine learning (ML). The backdrop underscores the growing significance of cyber-physical systems and the pressing need for advanced hardware capabilities.The research's core objective is to analyze and showcase advancements in hardware design, AI and ML integration, and the mitigation of security concerns. Methodologically, a rigorous examination of peer-reviewed literature and in-depth case studies from real-world implementations forms the foundation. These case studies encompass diverse sectors, providing genuine insights into the practical applications of HE-CPS. The findings spotlight a paradigmatic shift in hardware design, emphasizing heightened efficiency, speed, and integration capacities. The infusion of AI and ML emerges as a transformative force, enhancing adaptability and predictive capabilities. Addressing security and privacy concerns reveals tangible solutions, including robust encryption and authentication measures. Real-world case studies demonstrate successful HE-CPS implementations, illustrating tangible benefits in sectors such as healthcare and manufacturing. This research contributes substantively to the discourse on the trajectory of cyber-physical systems, offering a comprehensive overview of recent advancements

Conformance Testing as Falsification for Cyber-Physical Systems

In Model-Based Design of Cyber-Physical Systems (CPS), it is often desirable to develop several models of varying fidelity. Models of different fidelity levels can enable mathematical analysis of the model, control synthesis, faster simulation etc. Furthermore, when (automatically or manually) transitioning from a model to its implementation on an actual computational platform, then again two different versions of the same system are being developed. In all previous cases, it is necessary to define a rigorous notion of conformance between different models and between models and their implementations. This paper argues that conformance should be a measure of distance between systems. Albeit a range of theoretical distance notions exists, a way to compute such distances for industrial size systems and models has not been proposed yet. This paper addresses exactly this problem. A universal notion of conformance as closeness between systems is rigorously defined, and evidence is presented that this implies a number of other application-dependent conformance notions. An algorithm for detecting that two systems are not conformant is then proposed, which uses existing proven tools. A method is also proposed to measure the degree of conformance between two systems. The results are demonstrated on a range of models

Content Modification Attacks on Networked Robotic Systems

With the advent of communication networks in robotic systems, distributed networked robotic systems can be deployed to perform certain tasks collaboratively. However, this makes the networked robotic systems vulnerable to cyber attacks. Thus, the rigorous study of the impact of cyber attacks and the development of corresponding defense mechanisms are necessary. In this dissertation, the cyber-physical security issue of networked robotic systems is studied under a specific type of cyber attack called content modification attack, which can modify the data content transmitted in the communication networks among the robots. Specifically, algorithms for attack design and detection for content modification attacks are studied. The physics of the robotic system is utilized to design and detect the cyber attacks for networked robotic systems. Content modification attacks are studied for the synchronization problem in networked robotic systems. The considered systems include multi-robot systems, bilateral teleoperation systems and bilateral tele-driving systems. To demonstrate the potential severity of the attack, a constructive methodology for attack design is also developed. Specifically, a destabilizing content modification attack referred to as a malignant content modification attack (MCoMA) is designed based on the system storage function, which can lead to system instability and even physical system damage. To protect the system, a physics-based attack detection scheme with an encoding-decoding structure is proposed for general content modification attacks. As part of the tele-driving system study, a novel passivity-based adaptive bilateral tele-driving control scheme is also proposed in the presence of network delays and dynamics parametric uncertainties. Simulations and experiments have also been conducted to validate the proposed algorithms. This study demonstrates the potential of utilizing the physics of the robotic system to better understand and strengthen the security of the networked robotic systems

Distributed estimation techniques forcyber-physical systems

Nowadays, with the increasing use of wireless networks, embedded devices and agents with processing and sensing capabilities, the development of distributed estimation techniques has become vital to monitor important variables of the system that are not directly available. Numerous distributed estimation techniques have been proposed in the literature according to the model of the system, noises and disturbances. One of the main objectives of this thesis is to search all those works that deal with distributed estimation techniques applied to cyber-physical systems, system of systems and heterogeneous systems, through using systematic review methodology. Even though systematic reviews are not the common way to survey a topic in the control community, they provide a rigorous, robust and objective formula that should not be ignored. The presented systematic review incorporates and adapts the guidelines recommended in other disciplines to the field of automation and control and presents a brief description of the different phases that constitute a systematic review. Undertaking the systematic review many gaps were discovered: it deserves to be remarked that some estimators are not applied to cyber-physical systems, such as sliding mode observers or set-membership observers. Subsequently, one of these particular techniques was chosen, set-membership estimator, to develop new applications for cyber-physical systems. This introduces the other objectives of the thesis, i.e. to present two novel formulations of distributed set-membership estimators. Both estimators use a multi-hop decomposition, so the dynamics of the system is rewritten to present a cascaded implementation of the distributed set-membership observer, decoupling the influence of the non-observable modes to the observable ones. So each agent must find a different set for each sub-space, instead of a unique set for all the states. Two different approaches have been used to address the same problem, that is, to design a guaranteed distributed estimation method for linear full-coupled systems affected by bounded disturbances, to be implemented in a set of distributed agents that need to communicate and collaborate to achieve this goal