Most structured design methods claim to address the needs of hard real-time systems. However, few contain abstractions which directly relate to common hard real-time activities, such as periodic or sporadic processes. Furthermore, the methods do not constrain the designer to produce systems which can be analyzed for their timing properties. In this article we present a structured design method called HRT-HOOD (Hard Real-Time Hierarchical Object Oriented Design). HRT-HOOD is an extension of HOOD, and includes object types which enable common hard real-time abstractions to be represented. The method is presented in the context of a hard real-time system life cycle, which enables issues of timeliness and dependability to be addressed much earlier on in the development process. We argue that this will enable dependable real-time systems to be engineered in a more cost effective manner than the current practice, which in effect treats these topics as performance issues. To illustrate our approach we present a simple case study of a Mine Drainage Control System, and show how it can be designed using the abstractions presented in the article.

Hrt-Hood: A Structured Design Method for Hard Real-Time ADA Systems

This paper provides a comprehensive overview of long-term R&D activities of the Rockwell Automation (RA) company in the field of holonic and agent-based manufacturing control systems. It presents a coherent framework of methodologies for designing agent-based control systems, tools that support implementation and validation of them, and agent applications that were developed for various industrial systems. The common attribute is the integration of novel techniques, such as multiagent systems or semantics with the current “old-fashioned” automation architectures represented mainly by programmable logic controllers. Retaining the ability of the control system to meet the strict real-time constraints and concurrently raise its intelligence has always been of highest importance. The paper does not focus merely on RA's work, but discusses all its aspects in a context of other existing works in this area.

Rockwell Automation's Holonic and Multiagent Control Systems Compendium

The development of complex embedded control systems can be improved significantly by applying formal techniques from control engineering and software engineering. It is shown how these approaches can be combined to improve the design and analysis of high-tech systems, both in theory and practice. The semantics of the integration of two established rigorous techniques has been defined formally in this work. The strength of this integrated semantics is demonstrated by means of a significant industrial case study: the embedded control of a printer paper path, whereby the full development life-cycle from model to realization is covered. The resulting model-driven design approach fits the current engineering practice in industry and is both flexible and effective.

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Modeling and validating distributed embedded real-time control systems

The main subject of the book is the description of built-in contract testing a test organization for component-based applications founded on building test artifacts directly into components. It makes individual components more controllable and observable, and thus more testable through built-in testing interfaces. These provide extra functionality that is specifically geared towards facilitating testing. It also promotes the use of component testers in components that contain test cases for checking a component?s environment, this is its run-time environment as well as associated sub-components. Since building testing into components has implications with component development, built-in contract testing is integrated with and made to complement a model-driven development method. The book describes a method for developing the testing of components in parallel with their functionality based on models. It means UML models are used to derive the testing architecture for an application, the testing interfaces and the component testers. The method also provides a process and guidelines for modeling and developing these artifacts. The book will also discuss the implications of built-in contract testing with other component-based development technologies such as product-line engineering, middleware platforms, reuse principles etc. It will also describe a new method for specifying and checking real-time properties of object-oriented, component-based real-time systems that is based on dynamic execution time analysis with optimization algorithms.

Component-Based Software Testing with UML

A language for modular spatio-temporal simulation

HOOD method finding objects and operations object description skeleton class and instance objects real-time design Ada source code generation distributed software design developments of HOOD.

Peter J. Robinson

Papers

Hierarchical object-oriented design