Study on Simulation and Fatigue Assessment Method for Shipbuilding Manual Operation in Narrow Space

There are numerous pieces of machinery, pipelines, and cables on the ship. Therefore, the overall space resource is limited. Workers working within a narrow space are at a higher risk for work-related musculoskeletal disorders (WMSDs). This research builds a simulation and fatigue assessment system for shipbuilding operation in narrow spaces to reduce WMSDs risk. Firstly, a Loop-Nesting-Ward clustering algorithm (LNW) is constructed to build the human posture library. Then, based on the target optimization and Newton-Raphson algorithm, a posture matching and optimization method is proposed. In addition, a fatigue assessment model is developed based on body statics and Maximum Endurance Time (MET). Finally, a case study is demonstrated, and results show that the LNW algorithm is better for building posture library. After the simulation, flexible job posture can be generated. The fatigue assessment results show that workers should work for less than 9.68 minutes, or the ship structure became more spacious, to limit the danger of WMSDs. The method provides an effective assessment for the optimization of worker operations, equipment layout, and cabin space throughout the ship design stage.