Towards Time-Sensitive Behavioral Contract Monitors for IEC 61499 Function Blocks

Duc Do Tran, Kim Grüttner, Jörg Walter and Frank Oppenheimer
3rd IEEE International Conference on Industrial Cyber-Physical Systems (ICPS 2020)
The IEC standard 61499 defines a generic model for distributed industry control systems. It offers high flexibility through an event-driven model of execution. The downside of such models is that they can be difficult to analyze and debug.The central modeling element of IEC 61499 is the function block (FB), a composable representation of behaviour activated through event ports, with optional data ports. We adopt the concept of contracts for FBs to allow the specification of assumptions and guarantees over data/event traces of their input and output ports.This work proposes an initial concept for integrating time-sensitive behavioural contracts with IEC 61499 FBs. We propose specification patterns and a tool that supports the automatic generation and integrating of contract monitors into IEC 61499 FB models. These monitors observe an FB's input and output values/events and check that assumptions and guarantees hold. We evaluate our proposed concept on a simple pick and place control system that is modeled in 4diac, an open source IEC 61499 framework.
06 / 2020
Electronics and ICT as enabler for digital industry and optimized supply chain management covering the entire product lifecycle