Vol.3 No.3 2010

Research paper−197−Synthesiology - English edition Vol.3 No.3 pp.197-213 (Dec. 2010) the components, and the behavior may not occur consistently (inconsistency) according to the system specification. The cooperative behavior by the system components is generally tested in a system test conducted in the final phase of system development where actual products of the components are combined. In a case where inconsistency of the cooperative behavior is detected in the system test, it is necessary to return to the upstream of the system development and redesign the cooperative behavior by the components. Large amount of cost is required to correct such inconsistency. When redesigning of the cooperative behavior occurs in the final phase of system development, the reliability of the system may be compromised. Although it is necessary to design and verify the cooperative behavior by the system components surely in the upstream of system development, no method has been proposed for this purpose. The first reason is that there has been no attention paid to the cooperative behavior by the system components from the perspective of the reliability of the system. The second reason is that incorporating the quality of the system at the upstream of system development is a relatively new concept. Therefore, we study a methodology for decomposing a system specification into component specifications and interface specifications, and verifying consistency of their cooperative behavior in the system design phase[5][6]. By developing the components based on the specifications where the cooperative behavior is consistent, it is expected to improve the reliability of the complex system. This methodoloy is constructed by synthesizing architectural design methodTerm 8 in systems engineering[1] Term 7 and model checking[7] Term 9.Systems engineering is technological methodologies for achieving systems which satisfy the required quality within a given budget and time period. The research of 1 IntroductionSystem is a combination of interacting elements organized to achieve one or more stated purposesTerm 1[1]. Through advances in technology, technological systems (or systems) such as electronic equipment systemsTerm 2 or information systemsTerm3 have become deeply ingrained in society. On the other hand, the systems are getting more and more complex with the sophistication of required functions and the advent of system of systemsTerm 4 where a new system is formed by multiple systems with different purposes. Recently, there are many system failures due to their complexity. As seen in the accident cases of irradiation device[2], explosion of Ariane 5[3], or disruption in air traffic control system[4], the failures of complex systems have drastic influences on society. Improving the reliability of complex systems is an important issue in realizing a safe and secure society.In the complex system, components of the system are connected and cooperate with each other. For example, in the case of the irregular-rigid-body-transport robot system which is described in chapter 5, the integrated control subsystem understands the surrounding situation based on the results of measurement by the measurement subsystem, and the robot subsystem operates accordingly. This is called cooperative behaviorTerm 5 by components in this paper. In detail, processings of the system component cooperate with processings of the other system components through the interface between components in order to achieve the system function. In the complex system, it is important that the cooperative behavior by the components occurs consistently (consistencyTerm 6) according to the system specification. However, due to its complexity, errors may creep into the specifications for the cooperative behavior by - Synthesis of architectural design method and model checking -Atsushi Katoh*, Masataka Urago and Yoshiaki OhkamiGraduate School of System Design and Management, Keio University 4-1-1 Hiyoshi, Kohoku-ku, Yokohama 223-8526, Japan*E-mail : Original manuscript received January 19, 2010, Revisions received June 4, 2010, Accepted June 7, 2010 This paper describes a methodology for decomposing a system specification into component specifications and interface specifications whose cooperative behavior is consistent with each component. The methodology is constructed by a bridge method of combining architectural design method in systems engineering standards and model checking, which have already been confirmed to be effective in developing systems. As a trial, the methodology was applied to develop an industrial robot system. The result demonstrates that the proposed methodology is effective for complex industrial systems.A methodology for improving reliability of complex systemsKeywords : Developing methodology, systems engineering, architectural design method, model checking, bridge method, complex systems, reliability[Translation from Synthesiology, Vol.3, No.3, p.197-212 (2010)]


page 12