Steel modular construction offers significant benefits but remains constrained by high product variety and fragmented systems. This paper presents the design and industrial deployment of an intelligent off-site manufacturing system tailored to steel modular buildings, with GS-Building and ME-House as representative product families. The system organises profile and plate preparation, sub-assembly, final welding and straightening, and inspection and logistics into a continuous, flow-oriented line supported by flexible automation, including automated cutting and marking with nesting optimisation, jig-based assembly, horizontal welding and sensor-assisted straightening of H-sections, parametric robotic welding for most non-standard members, and intelligent logistics using vision-guided handling devices, automated guided vehicles and dynamic storage. These physical processes are integrated through a cyber-physical ‘digital backbone’ comprising an optical network, manufacturing execution system and a production-line digital twin for real-time traceability. Prototype deployment and comparative analysis against conventional steel fabrication show that the system replaces error-prone manual data handovers with a continuous digital thread, enables dynamic scheduling and just-in-time logistics and turns the workshop from a black box into a transparent, data-driven environment. The results demonstrate a practical pathway for industrialising steel modular construction and a foundation for future data-driven optimisation.
Xiao et al. (Tue,) studied this question.