Novel Four-Cell Lenticular Honeycomb Deployable Boom with Enhanced Stiffness

Area of Science:

• Space Engineering
• Materials Science
• Mechanical Engineering

Background:

• Composite thin-walled booms are crucial for self-deploying space structures like antennas and solar sails.
• Releasing stored strain energy enables efficient folding and deployment.
• Existing designs require optimization for enhanced performance and reliability.

Purpose of the Study:

• To propose and optimize a novel four-cell lenticular honeycomb deployable (FLHD) boom.
• To analyze the coiling dynamics of the FLHD boom under pure bending.
• To develop an optimal design method for coiling, considering peak moment, maximum stress, and mass.

Main Methods:

• Nonlinear explicit dynamics analysis for coiling dynamics simulation.
• Back propagation neural network (BPNN) for developing an optimal design method.
• Full factorial experimental design with 36 sample points to create surrogate models.
• Non-dominated sorting genetic algorithm-II (NSGA-II) for multi-objective optimization using ISIGHT software.

Main Results:

• Surrogate models for coiling peak moment (M) and maximum principal stress (S) were established using BPNN.
• An optimization strategy was developed to minimize wrapping moment and mass while constraining maximum stress.
• The coiling process was simulated in three steps: flattening, holding, and hub coiling.

Conclusions:

• The developed optimal design method effectively addresses FLHD boom coiling dynamics.
• The optimization process avoids fatigue cracks by managing stress concentrations.
• The study provides a robust approach for designing deployable composite booms for space missions.