DCSYNTH: Guided Reactive Synthesis with Soft Requirements for Robust Controller and Shield Synthesis

DCSYNTH is a tool for the synthesis of controllers from safety and bounded liveness requirements given in interval temporal logic QDDC. It investigates the role of soft requirements (with priorities) in obtaining high quality controllers. A QDDC formula specifies past time properties. In DCSYNTH synthesis, hard requirements must be invariantly satisfied whereas soft requirements may be satisfied "as much as possible" in a best effort manner by the controller. Soft requirements provide an invaluable ability to guide the controller synthesis. In the paper, using DCSYNTH, we show the application of soft requirements in obtaining robust controllers with various specifiable notions of robustness. We also show the use of soft requirements to specify and synthesize efficient runtime enforcement shields which can correct burst errors. Finally, we discuss the use of soft requirements in improving the latency of controlled system.