Accuracy Analysis and Synthesis of Planar Mechanism for Antenna Based on Screw Theory and Geometric Coordination

To address the deployment accuracy issues of multi-frequency band reflector antennas, this study takes a hexagonal prism modular deployable antenna as an example and proposes an accuracy design method. This paper proposes a screw-theory-based sub-chain precision analysis method. This method constructs a virtual screw model of rod length errors and hinge gap errors. Based on geometric relationships, a multi-loop point position error model is established, and accuracy surfaces considering rod length errors and hinge gap are output using MATLAB R2024b. By outputting the relationship curves of single-rod errors relative to point errors, the linearized influence law of individual rods on precision is further elucidated. Simulation results demonstrate the reliability of the error modeling theory. Based on the established cost-effective precision model and the minimum point error, which is obtained by using the numerical iterative method, the optimal solution for error parameters is obtained.