Multi-Agent Modelling of Industrial Cyber-Physical Systems for IEC 61499 Based Distributed Intelligent Automation

Traditional industrial automation systems developed under IEC 61131-3 in centralized architectures are statically programmed with determined procedures to perform predefined tasks in structured environments. Major challenges are that these systems designed under traditional engineering techniques and running on legacy automation platforms are unable to automatically discover alternative solutions, flexibly coordinate reconfigurable modules, and actively deploy corresponding functions, to quickly respond to frequent changes and intelligently adapt to evolving requirements in dynamic environments. The core objective of this research is to explore the design of multi-layer automation architectures to enable real-time adaptation at the device level and run-time intelligence throughout the whole system under a well-integrated modelling framework. Central to this goal is the research on the integration of multi-agent modelling and IEC 61499 function block modelling to form a new automation infrastructure for industrial cyber-physical systems. Multi-agent modelling uses autonomous and cooperative agents to achieve run-time intelligence in system design and module reconfiguration. IEC 61499 function block modelling applies object-oriented and event-driven function blocks to realize real-time adaption of automation logic and control algorithms. In this thesis, the design focuses on a two-layer self-manageable architecture modelling: a) the high-level cyber module designed as multi-agent computing model consisting of Monitoring Agent, Analysis Agent, Self-Learning Agent, Planning Agent, Execution Agent, and Knowledge Agent; and b) the low-level physical module designed as agent-embedded IEC 61499 function block model with Self-Manageable Service Execution Agent, Self-Configuration Agent, Self-Healing Agent, Self-Optimization Agent, and Self-Protection Agent. The design results in a new computing module for high-level multi-agent based automation architectures and a new design pattern for low-level function block modelled control solutions. The architecture modelling framework is demonstrated through various tests on the multi-agent simulation model developed in the agent modelling environment NetLogo and the experimental testbed designed on the Jetson Nano and Raspberry Pi platforms. The performance evaluation of regular execution time and adaptation time in two typical conditions for systems designed under three different architectures are also analyzed. The results demonstrate the ability of the proposed architecture to respond to major challenges in Industry 4.0

Multi-skeleton model for top-down design of complex products

Generally, there are two alternative design approaches available to engineers: bottom-up and top-down. Considering the sharp increase in the complexity of most mechanical products, the top-down design approach is more widely adopted in the development of complex products. However, in traditional top-down design process, design parameters are communicated through single-skeleton models, and design units are strongly coupled due to the multi-dimensional complexity of products. Toward this end, a new top-down design approach based on multi-skeleton model is proposed in this article. First, in accordance with different kinds of design parameters, three major skeleton models are defined, including location skeleton model, published skeleton model, and design skeleton model. And the characteristics of multi-skeleton models are also described. Then, the top-down design process based on the multi-skeleton model is explored, especially in the multi-skeleton modeling phase. It is also illustrated in detail that how to realize design parameter transmission and design unit reuse. Subsequently, it elaborates the communicating way and structure optimization of design parameters to support parameters controlled publishing and design units reuse. Finally, a meteorological satellite and a crawler crane design cases are implemented to expound the feasibility and effectiveness of the proposed framework