A unified V-shaped digital twin modeling paradigm of aircraft assembly systems for improving modeling accuracy and assembly quality

Digital Twin (DT) technology is one of the key approaches to enhancing the intelligence of aircraft assembly equipment. However, the diversity of such equipment types and significant structural differences present substantial challenges to the development of DT models. This article proposes a unified V-shaped DT modeling paradigm to support high-accuracy and structured modeling. The robotic drilling system is used as an example to validate this paradigm. The modeling requirements of this system are established based on a comprehensive analysis of its structural characteristics and operational tasks. A corresponding virtual entity is constructed through parametric modeling based on kinematic analysis. The behavior model represents the interaction protocols and decision logic of the physical system, with basic modules for communication and behavioral analysis. These modules are then systematically integrated to form a complete task model for drilling. The structural validation of the virtual entity is performed, accompanied by the formulation of behavioral matching degree and task execution consistency to evaluate the effectiveness of the proposed modeling paradigm. Meanwhile, kinematic parameter identification is integrated to calibrate the virtual entity, thereby further enhancing the DT modeling accuracy. The experimental results show that the behavior matching degree for positioning after calibration is 0.204 ± 0.228 mm, with an increase of 78.71 %. The average errors of hole position and diameter are reduced by 78.43 % and 14.27 %, respectively, after calibration. The corresponding task execution consistency is improved to 1.465 and 1.462. This indicates that the high-accuracy DT model constructed by the proposed paradigm effectively enhances the intelligence and assembly quality of the equipment.