Modern cyber-physical systems (CPS) are often developed in a model-based development (MBD) paradigm. The MBD paradigm involves the construction of different kinds of models: (1) a plant model that encapsulates the physical components of the system (e.g., mechanical, electrical, chemical components) using representations based on differential and algebraic equations, (2) a controller model that encapsulates the embedded software components of the system, and (3) an environment model that encapsulates physical assumptions on the external environment of the CPS application. In order to reason about the correctness of CPS applications, we typically pose the following question: For all possible environment scenarios, does the closed-loop system consisting of the plant and the controller exhibit the desired behavior? Typically, the desired behavior is expressed in terms of properties that specify unsafe behaviors of the closed-loop system. Often, such behaviors are expressed using variants of real-time temporal logics. In this chapter, we will examine formal methods based on bounded-time reachability analysis, simulation-guided reachability analysis, deductive techniques based on safety invariants, and formal, requirement-driven testing techniques. We will review key results in the literature, and discuss the scalability and applicability of such systems to various academic and industrial contexts. We conclude this chapter by discussing the challenge to formal verification and testing techniques posed by newer CPS applications that use AI-based software components.
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A Review on Origami Simulations: From Kinematics, To Mechanics, Toward Multiphysics
Abstract Origami-inspired systems are attractive for creating structures and devices with tunable properties, multiple functionalities, high-ratio packaging capabilities, easy fabrication, and many other advantageous properties. Over the past decades, the community has developed a variety of simulation techniques to analyze the kinematic motions, mechanical properties, and multiphysics characteristics of origami systems. These various simulation techniques are formulated with different assumptions and are often tailored to specific origami designs. Thus, it is valuable to systematically review the state-of-the-art in origami simulation techniques. This review presents the formulations of different origami simulations, discusses their strengths and weaknesses, and identifies the potential application scenarios of different simulation techniques. The material presented in this work aims to help origami researchers better appreciate the formulations and underlying assumptions within different origami simulation techniques, and thereby enable the selection and development of appropriate origami simulations. Finally, we look ahead at future challenges in the field of origami simulation.
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- NSF-PAR ID:
- 10433809
- Date Published:
- Journal Name:
- Applied Mechanics Reviews
- Volume:
- 74
- Issue:
- 3
- ISSN:
- 0003-6900
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1115/1.4055031
