Modeling and analysis of controllable stiffness composite material flexures
File(s)
Author(s)
Almuslmani, Majed
Type
Thesis
Abstract
The stiffness of carbon fiber composite structures can be significantly reduced by incorporating interleaved thermoplastic material layers, when heated above the thermoplastic interleaf’s glass transition temperature. This is because the interleaved thermoplastic material changes from rigid and glassy to flexible and rubbery at temperatures above the glass transition temperature. Thus, these composite structures would possess high damping and shape memory capabilities. These characteristics make them an excellent choice for creating flexures for space applications that require controlled deployment. The damping and shape memory properties of these composite materials with thermoplastic interleaves hold enormous potential for designing spacecraft hinges that enable soft and controlled deployment, thereby helping to limit shock loads and overshoot accelerations in deployable space structures.
A comprehensive methodology has been developed using the finite element method to design and analyze flexures made of carbon fiber composite materials with thermoplastic materials interleaves. The finite element analysis considers the viscoelasticity of the interleaved polymer and the carbon fiber composite materials, enabling accurate predictions of mechanical and dynamic responses, including the stowage process, stress relaxation, recovery time, and deployment characteristics. Experimental validation tests have been conducted to display the efficacy of the developed finite element modeling methodology in accurately predicting the behavior of the flexure made of composite materials with thermoplastic interleaves in different phases, including the stowage and deployment phases.
The developed finite element procedure is used to design and analyze an innovative tape spring hinge made of carbon fiber composite materials interleaved with thermoplastic materials. Experimental tests were conducted to evaluate the developed tape-spring hinges as deployment flexures for space structures. The results demonstrate that the developed tape-spring hinges with adjustable stiffness can effectively meet the deployment requirements of limiting shock and overshooting loads.
A comprehensive methodology has been developed using the finite element method to design and analyze flexures made of carbon fiber composite materials with thermoplastic materials interleaves. The finite element analysis considers the viscoelasticity of the interleaved polymer and the carbon fiber composite materials, enabling accurate predictions of mechanical and dynamic responses, including the stowage process, stress relaxation, recovery time, and deployment characteristics. Experimental validation tests have been conducted to display the efficacy of the developed finite element modeling methodology in accurately predicting the behavior of the flexure made of composite materials with thermoplastic interleaves in different phases, including the stowage and deployment phases.
The developed finite element procedure is used to design and analyze an innovative tape spring hinge made of carbon fiber composite materials interleaved with thermoplastic materials. Experimental tests were conducted to evaluate the developed tape-spring hinges as deployment flexures for space structures. The results demonstrate that the developed tape-spring hinges with adjustable stiffness can effectively meet the deployment requirements of limiting shock and overshooting loads.
Version
Open Access
Date Issued
2024-03-17
Date Awarded
2024-10-01
License URL
Advisor
Santer, Matthew
Sponsor
Madīnat al-Malik ʻAbd al-ʻAzīz lil-ʻUlūm wa-al-Tiqnīyah
Publisher Department
Aeronautics
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)