## 1 Introduction
integrated automated scheduling tools with DES models to create a safe simulation framework for mine scheduling, enabling rapid adjustments and evaluation of alternative strategies [28]. However, most existing simulation studies have been limited to relatively simple manufacturing environments, with limited attention given to the practical application of DES in complex product assembly workshops. In the aerospace manufacturing industry, particularly in the production of cabin sections, workshop-level resource allocation and workstation scheduling present substantial challenges. Existing simulation studies often fail to thoroughly investigate the coordination between AGV scheduling and workstation assignment, nor do they address the need for dynamic adjustments to material transport and task allocation during time-sensitive production cycles. As a result, although DES technology has been widely adopted across various industries, its application in complex product assembly workshops remains limited. This is especially true when it comes to optimizing scheduling under multi-resource constraints and dynamic operating conditions. This study integrates lean production principles with modern simulation technologies to achieve comprehensive optimization of complex product assembly workshops. Byconducting a detailed analysis of the manufacturing process and adhering to smart factory standards, techniques such as pull-based production, single-piece flow, and continuous flow are implemented. Plant Simulation software is selected for production line layout and functional modeling due to its robust discrete event simulation capabilities, flexible scalability, and strong support for complex production systems. These features enable effective validation of process logic and equipment configurations [29]. Compared to other simulation platforms, Plant Simulation demonstrates superior precision and adaptability when dealing with the complexity and dynamism of aerospace assembly lines. This integrated approach significantly enhances operational efficiency and equipment utilization, offering both theoretical and technical foundations for improving the sustainability and adaptability of aerospace manufacturing operations [30; 31]. The primary objective of this study is to utilize simulation tools to analyze preconfigured assembly lines, formulate a comprehensive planning and design strategy for complex product assembly workshops, and identify and address inefficiencies for further optimization. The main contributions of this study include the following:  
(1) This study proposes a DES-based optimization model that integrates AGV scheduling, workstation configuration, material replenishment, and production task scheduling. It effectively addresses scheduling challenges in dynamic, multi-resource production environments, particularly suited to the needs of complex product assembly workshops. (2) It fills a gap in the research on AGV scheduling optimization in aerospace assembly, introducing a novel integrated optimization framework that specifically tackles issues related to large component transportation and complex workstation coordination. (3) Clear optimization objectives and key performance indicators (KPIs) are defined, enabling a rigorous evaluation of the method's effectiveness in improving workstation utilization and overall production efficiency. (4) Simulation results confirm that the proposed approach significantly enhances AGV scheduling efficiency and resource utilization, highlighting its practical value for application in complex product assembly workshops. The structure of this article is as follows: Section 2 presents the comprehensive planning and design of the aerospace assembly line. Section 3 explains the modeling of the assembly workshop using simulation software. Section 4 analyzes the simulation results and introduces optimization measures based on the identified shortcomings. Section 5 concludes the study and proposes directions for future research.