Work

Rigid-Flexible Coupling Dynamic Modeling of Truss Deployable Antenna Based on a Non-Orthogonal Joint Coordinate System

Year: 2026

Type: preprint

Abstract: Cross-sectional deformation of fully parameterized absolute nodal coordinate formulation (ANCF) beams can affect the representation of revolute joint axes when an orthogonal tangent frame is used for joint modeling. To address this issue, a non-orthogonal cross-section frame that follows the local deformation of the beam cross-section is introduced as the joint coordinate system. The geometric relationship between the tangent and cross-section frames is derived, showing that the tangent frame introduces a joint axis direction error through orthogonalization under xy-shear deformation, whereas the cross-section frame retains the material-defined joint axis direction. The proposed frame is then used to formulate the revolute joint constraints and driving torsion springs, which are subsequently assembled according to the mechanism topology to establish the system-level dynamic equations. Numerical results for a basic deployable module of the truss deployable antenna show that the joint axis direction error of the tangent frame follows the xy-shear deformation predicted by the geometric analysis, whereas the cross-section frame remains aligned with the material-defined joint axis direction. Relative to the Adams/View reference simulation, the cross-section frame formulation reduces the standard deviation of the von Mises stress residual from 26.3 MPa to 2.9 MPa, corresponding to an approximately 89.0% reduction. Comparisons with Adams/View reference simulations under three torsion spring layouts show that the proposed model reproduces the principal position, velocity, and acceleration responses, as well as the deployment-shock-folding sequence. The proposed formulation provides an effective modeling approach for deployment prediction and dynamic design evaluation of flexible deployable structures.

Source: Research Square

DOI: 10.21203/rs.3.rs-10836358/v1