Experimental Investigation of Vibration for Spacecrafts Using 3D Printed Architected Cellular Materials

Abstract

Triply Periodic Material Structures have proven to have superior performance when compared to that of a solid equivalent. They exhibit superior mechanical properties with a high stiffness to weight ratio and energy absorption. Hence, a lot of research and experiments are ongoing to investigate different TPMS strut, skeletal, and sheet based structures and their potential applications in several industries such as space applications. In this research the ability of 3 TPMS sheet based structure Gyroid, Diamond, and Primitive to obtain their first mode of vibration experimentally through a sine weep test according to QB50 requirements. In addition to, the effect of relative density cell size and cellular structure on the natural frequency. 2 samples per structure were additively manufactured using SLA techniques, each sample was tested in 3 directions Printing Direction (PD), Transverse Direction-1 (TD-1), and Transverse Direction-2 (TD-2) on an electrodynamic low-force shaker VDS-780. The main findings of the experiment were that all the TPMS sheet based structures exhibit isotropic behavior in all directions with the Primitive structure having the highest natural frequency at 20% relative density of 704 Hz. Additionally, three parameters effect the natural frequency type of structure, relative density and cell size. As the relative density increases the natural frequency increases. That is the case until high relative densities are reached, then the differences in natural frequency between the structures decreases. On the other hand, as the cell size decreases the natural frequency increases drastically. The three TPMS sheet based structures are showing a high potential for space application, since their first mode of vibration is higher than 100 Hz in both the transvers and printing direction.

Date of Award	Jul 2020
Original language	American English
Supervisor	Rashid Abu Al Rub (Supervisor)