Managing Run-Time Variability in Robotics Software by Modeling Functional and Non-functional Behavior

摘要

Service robots act in open-ended and natural environments. Therefore, due to the huge number of potential situations and contingencies, it is necessary to provide a mechanism to express dynamic variability at design-time that can be efficiently resolved on the robot at run-time based on the then available information. In this paper, we present a modeling process to separately specify at design-time two different kinds of dynamic variability: (ⅰ) variability related to the robot operation, and (ⅱ) variability associated with QoS. The former provides robustness to contingencies, maintaining a high success rate in robot task fulfillment. The latter focuses on the quality of the robot execution (defined in terms of non-functional properties like safety or task efficiency) under changing situations and limited resources. We also discuss different alternatives for the run-time integration of the two variability management mechanisms, and show real-world robotic examples to illustrate them.