An Integrated CAD-MBD-FEM Framework for Virtual Prototyping of a New Foldable Mechanism for Deployable Propulsor Support in Urban Air Mobility Vehicles

This paper presents a novel deployable mechanism for Urban Air Mobility (UAM) vehicles that supports propeller engines in flight and folds compactly for ground transport. To optimize this complex system, a rigorous Integration of Computer-Aided Design and Analysis (I-CAD-A) framework is developed in four sequential phases: 2D kinematic pre-dimensioning, detailed 3D geometric modeling, Multi-Body Dynamic (MBD) simulations to identify operational loads, and Finite Element Analysis (FEA) for structural verification. To bridge the critical data-transfer gap between dynamic MBD joint reactions and FEA structural boundaries, this study introduces and evaluates three novel load-transformation techniques: the Direct Reactions Method (DRM), the Moments Transformation Method (MTM), and the Loads Distribution Method (LDM). The proposed integrated approach yields a robust design for the foldable opening mechanism that supports propeller engines in autonomous urban air mobility vehicles, which serves as the paper's case study. In particular, the numerical experiments demonstrate that the proposed I-CAD-A framework yields a structurally sound, high-performance opening mechanism. Specifically, the proposed optimization process increased the minimum safety factor from the critical failure state of 0.22 to the standard value of 1.50, while incurring only a marginal mass penalty of 7.77%. Beyond the specific UAM application, this research provides a general, robust workflow for developing complex, articulated mechanical systems comprising rigid and flexible bodies. This research, therefore, not only proposes a new design for a foldable opening mechanism but also offers a detailed, structured, and robust methodology for developing complex mechanical systems composed of articulated rigid-flexible bodies.