CubeSat’s Deployable Solar Panel with Viscoelastic Multilayered Stiffener for Launch Vibration Attenuation

Abstract

Ensuring the structural safety of a deployable solar panel under a severe launch vibration environment is one of the important factors for a successful CubeSat mission. A CubeSat’s deployable solar panel proposed in this study is effective to guarantee the structural safety of solar cells by attenuating launch loads owing to the superior damping characteristic achieved by a multilayered stiffener with viscoelastic acrylic tapes. The demonstration model of 3 U CubeSat’s deployable solar panel was fabricated and tested to validate the effectiveness of the proposed design. The basic dynamic characteristics of the solar panel were measured through free-vibration tests according to the various layers of the stiffener. Moreover, the characteristics of the deployed solar panel were measured and investigated under various temperatures to predict its capability under in-orbit operation. The effectiveness of the proposed design for launch vibration attenuation was demonstrated through qualification level sine and random vibration tests.

Experimental Validation of a Highly Damped Deployable Solar Panel Module with a Pogo Pin-Based Burn Wire Triggering Release Mechanism

“…The results demonstrate that the application of the viscoelastic multilayered stiffener enhanced the vibration damping and increased the stiffness of the solar panel as the number of interlaminated layers increased owing to the large shear strain and relatively rough surface roughness between the viscoelastic and constraining layers [33]. Furthermore, in a previous study [24], the dynamic characteristic variation of solar panels under various temperature conditions, ranging from -20°C to 60°C, was investigated to predict their design effectiveness during in-orbit operation via free-vibration tests. These tests were performed in a thermal chamber with an isothermalization dwell time of 1 h at specified test temperatures.…”

“…Furthermore, the relative maximum dynamic displacement at the center of the solar panel was 0.03 mm during the z-direction excitation under a random vibration load, estimated from the three-sigma value of the G rms response. The maximum dynamic displacement of the proposed solar panel module was reduced significantly by a factor of 46.33 compared with that of the typical 3 U solar panel without a stiffener [24]. This is owing to the higher vibration attenuation resulted from the shear deformation of the viscous layers 0:00:00 26:00:00 52:00:00 78:00:00 104:00:00 130:00:00 11 International Journal of Aerospace Engineering of the acrylic tapes.…”

“…The solar panel's maximum resonance response of 8.95 g was observed at 51.59 Hz on the z-axis during the same axis excitation of the panel. For the same input vibration load, the maximum acceleration response of a typical 3 U solar panel without employing additional stiffeners in the z-axis excitation was 43.72 g, which was observed at a frequency of 47.60 Hz [24]. The acceleration response of the proposed solar panel reduced substantially, by a factor of 4.88, compared with that of the typical solar panel owing to the resistive shear deformation characteristic achieved using the laminated adhesive tapes; however, the 1 st eigenfrequency was lower than the expected value because of the torsional hinge backlash.…”

“…Thus, the handling of the nylon wire during the wire tightening process is considerably simpler and more reliable than that of conventional mechanisms in which the nylon wire is tightened on the flat surface of the solar panel. 5 shows the representative damping characteristics of solar panels according to various numbers of viscoelastic multilayered stiffener attachment conditions, obtained through freevibration tests performed at an ambient room temperature of 25°C under the boundary condition that both the hinge and the HRM holes interfaces are rigidly clamped [24]. The damping ratios calculated from the vibration period of solar w/o additional stiffener [24] with 3 layers of stiffener [24] with 5 layers of stiffener [24] with 5 layers of stiffener (module level) 6…”

“…In the present study, to overcome the aforementioned drawbacks of conventional deployable solar panels, we herein propose a novel high-damping deployable solar panel module combined with a pogo pin-based burn wire cutting HRM. A printed circuit board-(PCB-) based solar panel that employs multilayered stiffeners interlaminated with viscoelastic acrylic tapes was manufactured based on the results of a previous study [24], in which the basic dynamic characteristics of the panel with respect to the number of stiffener attachment conditions were demonstrated through freevibration tests. An important advantage of the proposed solar panel is that the dynamic deflection and stresses in the panel under launch vibration loads can be effectively minimized owing to the superior damping characteristic achieved using the multilayered stiffener with viscoelastic acrylic tapes.…”