Reliability, Maintainability, and Safety

Abstract

Within the last 20 years, digital automation has increasingly taken over manual control reliabilityfunctions in manufacturing plants, as well as in products. With this shift, reliability, safetymaintainabilitymaintainability, and safety responsibilities formerly delegated to skilled human operators have increasingly shifted to automation systems that now close the loop. In order to design highly dependable automation systems, the original concept of design for reliability has been refined and greatly expanded to include new engineering concepts such as availability, safety, maintainability, and survivability. Technical definitions for these terms are provided in this chapter, as well as an overview of engineering methods that have been used to achieve these properties. Current standards and industrial dependable systempractice in the design of dependable systems are noted. The integration of dependable automation systems in multilevel architectures has also evolved greatly, and new concepts of control and monitoring, remote remotediagnosticssoftwaresafetydiagnostics, software safety, and automated reconfigurability are described. An extended example of the role of dependable automation systems at the enterprise level is also provided. Finally, recent research trends, such as automated verification, are cited, and many citations from the extensive literature on this topic are provided.