Method for encoding ontology reasoning on a programmable logic controller

摘要

A method is disclosed for operating a programmable logic controller which executes program(s) based on cycles having a predetermined cycle time in a predefined memory. An automated reasoning method based on an ontology and a description logic is implemented in the programmable logic controller. To enable this, at least the concepts and roles of the ontology are encoded using index numbers and the axioms of the ontology are encoded using tuples of integral index numbers. The automated reasoning method is interrupted before the end of a cycle and subsequently resumed at the current status of program execution. This allows for the cyclic programming paradigm of a programmable logic controller. The method can be used for any types of programmable logic controller, e.g., controllers of devices belonging to an automation system or energy generation devices. In such scenarios the automated reasoning method may be used for diagnosing the corresponding devices.

主权项

1. A method for operating a programmable logic controller which executes one or more programs based on cycles having a predetermined cycle time in a predefined memory, wherein at least one executed program is an automated reasoning method based on an ontology and a description logic, wherein the ontology contains a plurality of data elements comprising at least concepts and roles as well as a plurality of axioms of predetermined axiom types, wherein an axiom represents an assertion in relation to one or more data elements of the ontology, the method comprising:
encoding the data elements using integral index numbers; encoding the axioms using tuples of integral index numbers, wherein a respective tuple comprises an integral index number encoding the axiom type of the axiom and the at least one index number that encode the one or more data elements contained in the assertion of the axiom; interrupting the automated reasoning method before an end of a cycle and storing the current status of the program execution of the method; and resuming the automated reasoning method in a next cycle based on the stored current status of the program execution.