Minimising Makespan of Discrete Controllers: A Qualitative Approach

EZEQUIEL CASTELLANO; BRABERMAN VICTOR; DIPPOLITO R. NICOLAS; UCHITEL SEBASTIAN; KENJI TEI

Conferencia; 2019 IEEE Conference on Decision and Control (CDC); 2019

Qualitative controller synthesis techniques pro- duce controllers that guarantee to achieve a given goal in the presence of an adversarial environment. However, qualitative synthesis only produces one controller out of many possible solutions and typically does not provide support for expressing preferences over other alternatives. In this paper, we thus present a formal approach to reason about preferences qual- itatively, restricting attention to makespan of discrete event- based controllers for reachability goals. Time is reasoned upon symbolically, which relieves the user from providing concrete quantitative measures. In particular, we study the scenario in which durations of individual activities are not known up-front. We first show how controllers can be symbolically and fairly compared by fixing the contingencies. Then, we present an algorithm to produce controllers that are makespan-minimising