Architecture-Centric Software Development for Cyber-Physical Systems

We discuss the problem of high-assurance development of cyber-physical systems. Specifically, we concentrate on the interaction between the development of the control system layer and platform-specific software engineering for system components. We argue that an architecture-centric approach allows us to streamline the development and increase the level of assurance for the resulting system. The case study of an unmanned ground vehicle illustrates the approach

Towards a QoS Modeling and Modularization Framework for Component-based Systems

Current domain-specific modeling (DSM) frameworks for designing component-based systems provide modeling support for system’s structural as well as non-functional or quality of service (QoS) concerns. However, the focus of such frameworks on system’s non-functional concerns is an after-thought and their support is at best adhoc. Fur-ther, such frameworks lack strong decoupling between the modeling of the system’s structural composition and their QoS requirements. This lack of QoS modularization limits (1) reusability of such frameworks, (2) ease of their mainte-nance when new non-functional characteristics are added, and (3) independent evolution of the modeling frameworks along both the structural and non-functional dimensions. This paper describes Component QoS Modeling Lan-guage (CQML), which is a reusable, extensible, and platform-independent QoS modeling language that pro-vides strong separation between the structural and non-functional dimensions. CQML supports independent evolu-tion of structural metamodel of composition modeling lan-guages as well as QoS metamodel. To evaluate, we superim-pose CQML on a purely structural modeling language and automatically generate, configure, and deploy component-based fault-monitoring infrastructure using aspect-oriented modeling (AOM) techniques.

Timed Automata Models for Principled Composition of Middleware

Middleware for Distributed Real-time and Embedded (DRE) systems has grown more and more complex in recent years due to the varying functional and temporal requirements of complex real-time applications. To enable DRE middleware to be configured and customized to meet the demands of different applications, a body of ongoing research has focused on applying model-driven development techniques to developing QoS-enabled middleware. While current approaches for modeling middleware focus on easing the task of as-assembling, deploying and configuring middleware and middleware-based applications, a more formal basis for correct middleware composition and configuration in the context of individual applications is needed. While the modeling community has used application-level formal models that are more abstract to uncover certain flaws in system design, a more fundamental and lower-level set of models is needed to be able to uncover more subtle safety and timing errors introduced by interference between application computations, particularly in the face of alternative concurrency strategies in the middleware layer. In this research, we have examined how detailed formal models of lower-level middle-ware building blocks provide an appropriate level of abstraction both for modeling and synthesis of a variety of kinds of middleware from these building blocks. When combined with model checking techniques, these formal models can help developers in composing correct combinations of middleware mechanisms, and configuring those mechanisms for each particular application