Dynamic modeling and performance analysis of dual-arm manipulators for cabin docking operation with transmission errors

Cabin segment assembly critically determines the performance and safety of high‑end equipment in aerospace, aviation, shipbuilding, and energy sectors. This paper presents a hybrid serial‑parallel dual‑arm manipulator for cabin docking. Each arm provides four motion types (axial, vertical, radial, circumferential), and the modular design enables adaptation to varied cabin sizes with coordinated six‑degree‑of‑freedom movement. The kinematic model is established using the Denavit–Hartenberg method, the workspace is analyzed via Monte‑Carlo simulation, and B‑spline curves ensure smooth trajectory planning. To address control‑accuracy limitations, transmission‑error models for joint drives and a Stribeck friction model are integrated, identifying transmission‑induced harmonic disturbances and velocity‑dependent friction as dominant error sources. A quasi‑sliding mode controller (QSMC) is designed based on Newton–Euler dynamics to actively suppress disturbances, compensate for errors, and eliminate chattering typical of conventional sliding‑mode control. Compared to classical sliding mode control (SMC), the quasi‑sliding mode control (QSMC) strategy significantly improves the trajectory tracking performance. The maximum absolute tracking errors for joint displacement and the peak fluctuations in velocity tracking are effectively suppressed, with reductions ranging from 97.70% to 99.98%. Laser‑tracker‑based repeat positioning tests confirm that the accuracy of all joints and the end‑effector surpasses design specifications (e.g., joints within ±0.045 mm, end‑effector within ±0.047 mm). Further experimental evaluations verify that the dual‑arm cabin docking system achieves industrial‑grade performance, with attitude‑angle repeatability errors below 0.1 °, positional accuracy better than 0.2 mm, and attitude‑control accuracy better than 0.15 °—demonstrating its high precision and reliable engineering applicability.