@article{daye_lee_2023, title={Active Deployment of Ultra-thin Composite Booms with Piezoelectric Actuation}, volume={12483}, ISBN={["978-1-5106-6073-1"]}, ISSN={["1996-756X"]}, DOI={10.1117/12.2658004}, abstractNote={The efficacy of using piezoelectric actuators to initiate the dynamic deployment of bistable composite tape springs is evaluated in this paper. Ultra-thin composite booms such as tape springs and their cross-sectional variants have seen increased popularity in spacecraft structures due to enabling the precise deployment of flexible solar arrays, sails, reflectors, and antennas. They can elastically transition between the deployed “extended” position and the stowed “coiled” position while retaining superior stiffness, thermal properties, mass efficiency, and compactness when compared to thin-shelled metal booms and rigid articulated columns. Bistability in the coiled and extended states allows the boom to exhibit more controllable self-deployment and become reconfigurable, which could allow spacecraft to relocate, redeploy, and adapt to changing environmental conditions or mission objectives. Deployment systems commonly include motors and mechanical restraints that significantly contribute to mechanical complexity and spacecraft weight. Since bistable booms do not rely on elastic instability of packaging to initiate motion, a non-intrusive and lightweight actuation mechanism is needed to trigger deployment. This paper experimentally demonstrates how a Macro Fiber Composite (MFC) actuator can statically and dynamically excite a stowed composite tape spring to initiate unrolling into its extended state.}, journal={ACTIVE AND PASSIVE SMART STRUCTURES AND INTEGRATED SYSTEMS XVII}, author={Daye, Jacob G. and Lee, Andrew J.}, year={2023} }
 @article{lee_fernandez_daye_2023, title={Bistable Deployable Composite Booms with Parabolic Cross Sections}, volume={11}, ISSN={["1533-6794"]}, DOI={10.2514/1.A35840}, abstractNote={ The stable extended and coiled states of thin-shelled composite booms with parabolic cross sections are investigated in this paper. These conic shapes potentially offer greater stiffness properties when compared to circular cross sections, which is critical for improving the load-bearing performance of deployed booms. Inducing bistability through composite layups in parabolic booms would allow for controllable self-deployment due to a less energetic coiled state when compared to monostable booms. An inextensional analytical model is used to predict the stable coiled diameters of tape spring and collapsible tubular mast (CTM) booms with parabolic cross sections. The parabolic section is discretized into circular segments using biarc spline interpolation, which allows them to be integrated into the strain energy minimization procedure used to obtain the equilibrium states. When the parabolic booms are parametrically compared against circular booms with identical layups, flattened height, and mass, the former are found to generally have better stiffness performance while being less efficient in stowed volume, as evidenced by larger coiled diameters. Analytical coiled diameters and their strain energy are verified with finite element simulations for an optimal parabolic tape spring and CTM booms. Additional validation of the parabolic tape spring’s coiled diameter is provided by experimental measurements of boom specimens. }, journal={JOURNAL OF SPACECRAFT AND ROCKETS}, author={Lee, Andrew J. and Fernandez, Juan M. and Daye, Jacob G.}, year={2023}, month={Nov} }