Automated Deductive Verification for Ladder Programming

TL;DR

This paper introduces a tool that automates deductive verification for Ladder Logic programs, aiming to improve debugging efficiency and robustness in industrial PLC programming.

Contribution

The paper presents a novel, automated deductive verification tool based on Why3 for Ladder Logic, enhancing debugging processes for industrial PLC programs.

Findings

Automated verification reduces debugging time.

Improves robustness of Ladder Logic programs.

Provides a user-friendly debugging tool.

Abstract

Ladder Logics is a programming language standardized in IEC 61131-3 and widely used for programming industrial Programmable Logic Controllers (PLC). A PLC program consists of inputs (whose values are given at runtime by factory sensors), outputs (whose values are given at runtime to factory actuators), and the logical expressions computing output values from input values. Due to the graphical form of Ladder programs, and the amount of inputs and outputs in typical industrial programs, debugging such programs is time-consuming and error-prone. We present, in this paper, a Why3-based tool prototype we have implemented for automating the use of deductive verification in order to provide an easy-to-use and robust debugging tool for Ladder programmers.