Kinematics and Performance Analysis of a Deployable 7R Overconstrained Single-Loop Mechanism for Aerospace Platform

Abstract

This paper studies a special deployable 7R single-loop mechanism (SLM), which is characterized by its overconstraints, 1-DOF, and single-loop structure. Based on these characteristics, a series of performance evaluation indices, including the overconstraint performance, input and output motion/force transmission performance, and deploying/folding ratio, are proposed to evaluate its performance. To analyze these performances, the kinematics of the 7R SLM is analyzed. Then, these performance indices are used to evaluate the 7R SLM. The performance analysis result shows that the mechanism exhibits excellent performance. A 3D-printed prototype of the 7R overconstrained SLM is presented and used to assemble a deployable module. Their deploying motion verifies the assembly capability and deployability of the mechanism and its potential as a basic unit to construct more complex, overconstrained deployable mechanisms for aerospace platforms. This study plays a significant role in the analysis, design, and optimization of overconstrained SLMs while also providing theoretical support for applications in aerospace platforms and other related fields.