ABOUT MEAboutMe.html


Design and Implementation of Safety Critical Systems

Implementing software solutions in safety critical systems is a tedious and demanding task. In the past years, a rigid set of formal rules has been implemented by authorities. Following these rules by implementing fixed procedures, using tools to ensure conformity and applying strict testing strategies has helped a lot.

Unfortunately, the use of such formal procedures alone will uncover deficits in SW quality, but it will not improve the quality of the software. In my experience, testing strategies using the V-model  are helpful, but the worst bugs, sometimes really risk prone have been detected by „just playing around“ with the systems. Looking into such bugs, the overwhelming majority of them is related to the interaction of different modules, frequently racing conditions resulting in inconsistent combinations of system states.

While components by themselves can be relatively easily tested due to narrow interfaces and (hopefully) well defined protocols, integrating them to a complete workplace increases the complexity dramatically.  The user interface is usually the component, where this complexity has to be handled. Unfortunately, the way, common frameworks implement the HMI makes it quite difficult, to apply formal methods in the design and implementation of operating procedures.

Apart from more than ten years of experience using the V-model in the development of software for medical devices, I can offer a rich experience in model driven software development using formal methods and own tools for code generation with thousands of devices in the field with purely tool generated software.