Towards a Stepwise Variability Management Process for Complex Systems

Abstract

Complex systems are executed in environments with a huge number of potential situations and contingencies, therefore a mechanism is required to express dynamic variability at design-time that can be efficiently resolved in the application at run-time based on the then available information. We present an approach for dynamic variability modeling and its exploitation at run-time. It supports different developer roles and allows the separation of two different kinds of dynamic variability at design-time: (i) variability related to the system operation, and (ii) variability associated with QoS. The former provides robustness to contingencies, maintaining a high success rate in task fulfillment. The latter focuses on the quality of the application execution (defined in terms of non-functional properties like safety or task efficiency) under changing situations and limited resources. The authors also discuss different alternatives for the run-time integration of the two variability management mechanisms, and show real-world robotic examples to illustrate them.