Malfunction or breakdown of certain mission critical systems (MCSs) may cause losses of life, damage the environments, and/or lead to high costs. Therefore, recognition of emerging failures and preventive maintenance are essential for reliable operation of MCSs. There is a practical approach for identifying and forecasting failures based on the indicators obtained from real life processes. We aim to develop means for performing active failure diagnosis and forecasting based on monitoring statistical changes of generic signal features in the specific operation modes of the system. In this paper, we present a new approach for identifying emerging failures based on their manifestations in system signals. Our approach benefits from the dynamic management of the system operation modes and from simultaneous processing and characterization of multiple heterogeneous signal sources. It improves the reliability of failure diagnosis and forecasting by investigating system performance in various operation modes, includes reasoning about failures and forming of failures using a failure indicator matrix which is composed of statistical deviation of signal characteristics between normal and failed operations, and implements a failure indicator concept that can be used as a plug and play failure diagnosis and failure forecasting feature of cyber-physical systems. We demonstrate that our method can automate failure diagnosis in the MCSs and lend the MCSs to the development of decision support systems for preventive maintenance.

Smart cyber-physical systems (S-CPSs) are complex engineered systems empowered by cyber-physical computing and equipped with the capability of reasoning, learning, adapting, and evolving. As an outcome of data-driven dynamic computing, reasoning capabilities, and the run-time obtained own knowledge, nonlinear and emergent behavior of S-CPSs whilst in operation is an open issue, not experienced in the case of conventional technical systems. This paper analyzes the technical issues of run-time operation and emergent behavior of S-CPSs, reviews the current understanding and state of advancement in designing S-CPSs for run-time, explores the paradox, and issues of designing for run-time adaptation, and synthesizes some general principles that can be taken into consideration when addressing the challenges, first of all, in the context of advanced manufacturing systems. This paper introduces four levels of CPSs according to reasoning capabilities and adaptation freedom of systems, and recognizes the paradox that a system with a higher level of freedom requires a higher level of self-control and resource management according to the overall objective of operation. Specific and common design principles are presented and critically assessed for each advancement level of CPSs. The principles synthesized by the authors provide only a partial fulfillment of the generic need. The planned future research addresses these issues and proposes (largely implementation and application independent) genuine principles for system developers.

Complementing our previous publications, this paper presents the information schema constructs (ISCs) that underpin the programming of specific system manifestation feature (SMF) orientated information management and composing system models. First, we briefly present (1) the general process of pre-embodiment design with SMFs, (2) the procedures of creating genotypes and phenotypes of SMFs, (3) the specific procedure of instantiation of phenotypes of SMFs, and (4) the procedure of system model management and processing. Then, the chunks of information needed for instantiation of phenotypes of SMFs are discussed, and the ISCs designed for instantiation presented. Afterwards, the information management aspects of system modeling are addressed. Methodologically, system modeling involves (1) placement of phenotypes of SMF in the modeling space, (2) combining them towards the desired architecture and operation, (3) assigning values to the parameters and checking the satisfaction of constraints, and (4) storing the system model in the SMFs-based warehouse database. The final objective of the reported research is to develop an SMFs-based toolbox to support modeling of cyber-physical systems (CPSs).

Our long-term objective is to develop a software toolbox for pre-embodiment design of complex and heterogeneous systems, such as cyber-physical systems. The novelty of this toolbox is that it uses system manifestation features (SMFs) for transdisciplinary modeling of these systems. The main challenges of implementation of the toolbox are functional design- and language-independent computational realization of the warehouses, and systematic development and management of the various evolving implements of SMFs (genotypes, phenotypes, and instances). Therefore, an information schema construct (ISC) based approach is proposed to create the schemata of the associated warehouse databases and the above-mentioned SMF implements. ISCs logically arrange the data contents of SMFs in a set of relational tables of varying semantics. In this article we present the ISCs necessary for creation of genotypes and phenotypes. They increase the efficiency of the database development process and make the data relationships transparent. Our follow-up research focuses on the elaboration of the SMF instances based system modeling methodology.

This paper surveys the recent developments and future research opportunities in computer supported cooperative work in design. This domain of interest has been variously conceptualized and described in different publications. There is a broader interpretation that considers the entirety of product lifecycle as a target domain and aims at a holistic optimization of all related engineering processes by connecting them through design. There exists a narrower interpretation that concentrates on the enhancement of the product conceptualization and creative design activities in distributed, multidisciplinary and volatile environments. The former is most frequently referred to as collaborative engineering and the latter as collaborative design. The paper concentrates on collaborative design and investigates the concepts, advancements and issues from: (i) philosophical and theoretical, (ii) technological and infrastructural, (iii) organizational and methodological, (iv) social and cultural, (v) cognitive and behavioral perspectives. Based on literature sources and the own work of the author in the last three decades, it provides a broadly-based analysis of the related concepts, knowledge, means, systems and concerns in current research, development and application with the objective to point towards future progression opportunities. The paper identifies a gradual shift in the research interest from the technological and procedural aspects to the socio-cultural, inter-personal and informational aspects. It proposes that collaborative design is eventually about people and that mobile, ubiquitous and smart technologies create many new opportunities for conducting collaborative design. Semantics, pragmatics and apobetics of inter-personal interaction and communication play a key role in the success of collaborative design.

Presents an interface between a deformable body mechanics model and a rigid body mechanics model. What is novel with our approach is that the physical representation in both the models is the same, which ensures behavioral correctness and allows great flexibility. We use a mass-spring representation extended with the concept of volume, and thus contact and collision. All physical interaction occurs between the mass elements only, and thus there is no need for explicit handling of rigid-deformable or rigid-rigid body interaction. This also means that bodies can be partially rigid and partially deformable. It is also possible to change whether part of a body should be rigid or not dynamically. We present a demonstration example, and also possible applications in conceptual design engineering, geometric modeling, as well as computer animation.

Freeform features can be regarded as key elements of shape modeling. Commonly, features are defined, controlled and computed using parameters. We propose a feature formulation strictly based on the parameterization, as a mapping from an arbitrary set to some domain of interest. This formalism accommodates many of the common representation forms and in addition allows: the uniform definition of freeform features; the analysis of feature properties, such as their spatial coverage, differentiability, uniqueness, overlap; and the comparison of alternative parameterizations for a given type of feature, regarding user control and computation. We have investigated in detail two feature types, the ridge and the hole. The proposed parameterizations indeed provide both interactive control and automatic feature extraction, are the key functions of a flexible forward/backward design support tool. Numerical results of the freeform feature parameter extraction process are presented.