Design and validation techniques for critical programmable controllers

Designing a dependable system required two complementary actions: taking operational dependability specification into account, demonstrating and validating the operational dependability. These two interactive actions were implemented during the development of a tender for an industrial dependability control system. Under these conditions, new production concepts were defined and new assessment methods were tested. In this article, which is based on these tests, we shall give a detailed description of the two design aspects concerning dependability-oriented design and dependability assessment