Synchronization-oriented human-cyber-physical assembly workstation 4.0 systems under graduation intelligent manufacturing system

Abstract

“Industry 4.0 (I4.0)” was first released by Germany in 2011, which is regarded as the starting point of the fourth Industrial Revolution. The past decade has witnessed a great deal of research and practice efforts in exploring the benefits of I4.0 transformation in reshaping value creation, building new business models, and enhancing the strategic competitiveness of enterprises. By contrast with previous industrial revolutions triggered by a single disruptive technology, the driving force of I4.0 is considered to be the synthesis of cutting-edge technologies from many fields. Although it is difficult to exhaust the continual emerging technologies due to I4.0 is still in progress, the transformation features it has brought are already apparent, that is, end-to-end integration of engineering systems, vertical integration of manufacturing systems, and horizontal integration of value chains, which provides a lot of methodological, organizational, and practical innovation opportunities. In this context, this thesis focuses on exploring the I4.0 transformation in the organization, operation and management of assembly systems, and the following priority research works have been carried out. The first work explores the transformation of the organization and operation of the assembly workstation in the I4.0 era (AW4.0), which is the basic building block of assembly systems. A human-cyber-physical framework for AW4.0 is proposed to support the smart networking of hyper objects with human integration. A spatio-temporal synchronization strategy is developed to achieve the consistency of hyper objects coordination. A real-life case is carried out through a full-scale prototype to validate the potential benefits of AW4.0. Research perspectives based on three-dimensional synchronization strategies are also given. The second work presents a real-time data-driven hyper objects orchestrating for human-machine synchronization (RHYTHMS) based on a service-oriented human-to-machine architecture, in which model-reference adaptive fuzzy control is used for real-time information sharing and synchronous coordination of smart human-machine work systems. A real-life assembly case is carried out by AW4.0 to quantitatively analyze the benefits of RHYTHMS in proactive ergonomic risks mitigation. The third work proposes a real-time data-driven synchronous reconfiguration of smart assembly cell line (ACL) workshops (Sync-RAS) under the Graduation Intelligent Manufacturing System (GiMS). Computer vision is employed to realize real-time information visibility within assembly cells at the operation process level. An appropriate information-sharing architecture is designed to coordinate the ACL operations in rapid response to changing demands under GiMS. A Sync-RAS mechanism is proposed to optimize the reconfiguration of ACL. A real-life case is used to verify the benefits of Sync-RAS. The fourth work investigates the heterogeneous demand-capacity synchronization (HDCS) problem in ACL operations. An integrated and adaptive planning, scheduling, and execution framework with a hierarchical closed-loop structure is designed to incorporate appropriate decision-making mechanisms at different levels with proper real-time aggregated data feedback from different time horizons to solve the HDCS problem in dynamic environments. A modified GiMS is introduced to integrate the decision-making process at different levels and ensure smooth production in a synchronous manner. An industrial case is used to verify the production synchronization performance of the proposed approach.