On periodic schedules for deterministically timed Petri net systems

Abstract

Introduces a Petri net based perspective to periodic schedules. These are classified, according to the time interpretation in multiple-server semantics and/or transitions firing periodicity constraints, into strict and general periodic schedules. Using a net transformation rule, the computation of the general schedule class can be done through techniques for the strict subclass. A necessary and sufficient condition for the feasibility of a strict periodic schedule is given. Estimating the truncation error at initial firing time epoch tau /sub 1/ allows to get linear systems of inequalities as necessary conditions for a schedule to be feasible. An linear programming (LP) based heuristic approach is proposed to deal with the computation of 'optimum' (i.e. minimal time) strict periodic schedules under the single-server semantics.<>