Intrinsic Mode Analysis of Space Hinge Rod Deployment Mechanism_Hinge Knowledge_Tallsen 1

The rapid development of the space industry has necessitated the utilization of large-scale space deployment mechanisms to meet various application requirements. However, due to the limitation of space vehicle capacity, these mechanisms need to be folded and stored during the launch phase. When unfolded, these mechanisms may experience reduced rigidity, resulting in lower natural frequencies and undesirable coupling vibrations between the spacecraft body and the deployment mechanism. Therefore, it is essential to understand the factors influencing the natural frequency of the space hinge rod deployment mechanism for better design and calibration.

Abstract:

When different materials and reinforcement methods are employed in the space hinge rod expansion mechanism, their natural frequencies differ significantly. Modal analysis using finite element software ANSYS can be conducted to determine the impact of material density and reinforcement method on the natural frequency. The research findings indicate that material density has a significant influence on the natural frequency, with a greater impact observed for higher densities. Additionally, different reinforcement methods also lead to substantial natural frequency differences. This study provides valuable guidance for the dynamic analysis and further optimization of space hinge rod deployment mechanisms.

Model of Space Hinge Rod Deployment Mechanism:

The space hinge rod deployment mechanism consists of a frame part and a rod part, with a scissor support formed by the middle two rods of the frame and the rods. The frame is equipped with hinge shafts at both ends, allowing it to be hinged with the upper and lower frames. The rods' hinge shafts serve as three-point fixation, ensuring stability. Moreover, two strengthening structures are included: the connecting rod structure and the steel wire rope structure. The connecting rod reinforcement employs U-shaped rods connected in the same direction, while the steel wire rope reinforcement involves winding a steel wire rope around a roller for added rigidity.

Finite Element Model:

The frame and strut parts are modeled using solid three-dimensional modeling with the Solid45 unit. This unit accurately reflects the actual situation and provides precise results. On the other hand, the reinforcement part is modeled directly using the BEAM188 unit, offering powerful linear analysis capabilities and better section data definition functions. The beam element generates a one-dimensional mathematical model of the three-dimensional structure, enabling efficient and effective analysis.

Modal Analysis of Space Hinge Rod Deployment Mechanism:

Modal analysis aids in determining the vibration characteristics of the structure, including its natural frequency and mode shape. These parameters are crucial in bearing dynamic loads and serve as the basis for other dynamic analysis problems. Since the space expansion mechanism requires lightweight design, modal analysis of aluminum and carbon fiber materials with either connecting rod or steel wire rope reinforcement is conducted. The obtained fundamental frequencies are presented in Table 1.

The study reveals that the natural frequencies of space hinge rod deployment mechanisms vary based on the materials and reinforcement methods employed. Material density has a significant influence on the natural frequency, with higher densities leading to lower fundamental frequencies. Furthermore, different reinforcement methods result in substantial differences in the natural frequency. Overall, understanding these factors enables the selection of appropriate reinforcement methods and materials for improved performance of space hinge rod deployment mechanisms.

In conclusion, the research findings highlight the importance of considering material density and reinforcement method in the design and calibration of space hinge rod deployment mechanisms. The information provided in this study will aid in the accurate selection of materials and reinforcement methods, thus optimizing the dynamic performance and stability of space deployment mechanisms.