Petri nets-based digital twin drives dual-arm cooperative manipulation

Abstract

The emerging concept of digital twin (DT) creates a holistic vision to change how we view the design and operation of a cyber-physical system (CPS), and how to reconfigure its function and structure to deal with the scenario of complexity and uncertainty that arises from reality. In this work, we firstly surveyed the typical narrative frameworks of DT modelling: generalized layered method, decomposition and composition method, Asset Administration Shell framework, and standardized architecture. Secondly, the Petri nets-based digital twin framework for the robotic dual-arm cooperative system was presented in detail through the domain-based and entity-based systematization methodology. The proposed framework generated a conceptually embodied and situated DT environment, which not only represented the highly hybrid nature (i.e., continuous, discrete and cooperative) of the dual-arm cooperative operation process, but also avoided the complex decoupling calculation of closed kinematic chains in the bi-manual manipulation of industrial arms. Furthermore, two digital twin instances clearly demonstrated that the holonic integration of operational technologies equipment, information technologies and DT through the industrial internet of things manifested a game-changing potential to upgrade the capability of an existing brownfield CPS to perform complex tasks. Concluding, by coupling the discrete event simulation at the highly abstract level and the 3D offline programming simulation in the intuitively DT environment, this comprehensive practice of DT to transform the loose DT metaphor into strictly industrial domains provided an illuminating cross-increment for both the robotic community and the DT facilitators.