Pre-controller Synthesis for Runtime Controller Synthesis

Self-adaptive systems that operate to satisfy functional requirements in a changing environment are realized by reasoning with runtime models. Existing research has proposed such runtime modeling techniques, for example, reflecting changes in the environment in an environment model and synthesizing new behavior on the basis of the updated environment and requirement models by discrete controller synthesis. However, discrete controller synthesis increases the computation time exponentially as the model size of the environment and requirements increases, which poses a challenge for its application to resynthesizing controllers at runtime. In this paper, we propose a pre-computation controller synthesis that reduces the computation time by omitting a part of the synthesis process of the discrete controller synthesis performed when the environment changes. In the evaluation, we use a concrete system example to evaluate the usefulness of the pre-controller synthesis. As a result, we succeeded in reducing the execution time by up to 99.9% compared to the execution time of conventional controller synthesis.