About this Abstract |
Meeting |
2024 ASC Technical Conference, US-Japan Joint Symposium, D30 Meeting
|
Symposium
|
2024 ASC Technical Conference, US-Japan Joint Symposium, D30 Meeting
|
Presentation Title |
Structural Sizing of a 50-m-Tall Thermoplastic Composite Solar Array Truss Tower Structure for the Lunar South Pole |
Author(s) |
Andrew Bergan, Babak Farrokh, Arunkumar Satyanarayana, Will Grier, Kenneth Segal, John Chiu, Sandi Miller |
On-Site Speaker (Planned) |
Andrew Bergan |
Abstract Scope |
At the lunar south pole, solar arrays elevated by towers can achieve near continuous sunlight since the sun remains near the horizon. Recent studies suggest that 50-m-tall towers are appropriate for the power requirements to support a sustained lunar presence. Since the solar array must rotate about its vertical axis to track the Sun, it is assumed to be a tower payload, which facilitates early design studies by decoupling the tower from the rest of the system. While eventually towers may be constructed using materials sourced in-situ, initially structural elements will likely be brought from the Earth, deployed, and assembled. Thermoplastic composites offer the benefit of high specific stiffness and strength properties along with welding for assembly joints, and therefore represent a promising material system for this application. The focus of this paper is on the structural sizing of such towers. A set of expressions based on beam theory are presented for preliminary sizing of the truss tower structure for strength and buckling. The loading condition that drives sizing is base excitation resulting from moonquakes. Select tower design parameters are explored including height, member cross-section, material, and damping. A point design is developed further through finite element analysis and shows the importance of joint stiffness. Thermal loads are included and evaluated. A detailed local joint model is used to investigate the structural capability of the joint design. The results show a viable point design and highlight the factors most significant in the structural sizing. |
Proceedings Inclusion? |
Definite: Post-meeting proceedings |