Informal Fannal Design Verification: Experience from the Industrial Trenches

Design Verification is playing a growing role in building physical systems largely controlled by software. This is driven by the often acute and sometimes chronic rise of project cost and duration brought on by the increase in testing now needed. Formal methods, as a subset of Design Verification, offer the promise of exposing design and requirements anomalies very early in the engineering process. In practice, achieving these benefits has been hampered on the one hand by the need for highly specialized skills, and on the other by a lack of significant computational power needed for the largest, most complex systems, where the potential value is the greatest. But there are signs of an inflection point, and rigorous design verification is already being applied in a number of industries and companies. This inflection point is a product of three forces: 1) The increase of affordable and usable computational power, 2) the invention and optimization of new efficient algorithms, and 3) the availability of robust tooling that exploits both power and efficiency. This paper will describe joint efforts of tooling companies and engineering firms to develop a) a more informal approach to formal methods aiming to alleviate the need of specialized mathematical expertise, b) a flexible and interactive approach to these methods, and c) an application directed to those model-based designs relevant to the avionics industry. The paper will discuss both success and failures, technical and otherwise, as well as work that remains to be done to transition away from the early adopter segment and bring the benefits to a greater fraction of industry.