Mechanical Design and Development of a Suborbital Payload for Real-Time Data Acquisition and Structural Health Monitoring

Abstract

Real-time data acquisition and structural health monitoring (SHM) are in any aerospace black box. To facilitate the development of such technologies, test payload architectures must be designed to safely deliver experimental components to the environments they are expected to perform in. The purpose of this project was to design, analyze, assemble, and launch a payload enclosure system as part of a collaborative experiment involving SHM by New Mexico Tech and distributed data acquisition by Immortal Data Inc. Particular attention was given to the integration of the hardware pertaining to the SHM experiment. This experiment monitors the condition of a cantilever beam throughout the flight using an electro-mechanical impedance method. The enclosure mount was designed to tolerate the vibrational, thermal, and g-loads experience in suborbital flight. With these criteria in mind, ULTEM 1010, an industrial strength 3D printing material, was chosen due to its significant yield strength and low density when compared to other 3D printing material and aluminum candidates. To determine whether or not the tolerances and requirements are sufficiently met, finite element analysis of the payload structure was performed in COMSOL Multiphysics and Solidworks. Stresses due to acceleration loads, de-spinning events, and ground impact were evaluated and safety factors were determined. To enable the electro-mechanical impedance diagnostics, a thin piezoelectric wafer sensor was bonded to the beam and connected to a miniaturized impedance analyzer. This system allowed for local storage of the electro-mechanical impedance data. Validation of this experimental setup was performed in laboratory conditions in which the impedance of the beam was measured in several frequency bands. Based on dynamic characteristics of the beam, low frequency bandwidth was selected for impedance analysis. Numerical studies confirm the enclosure design’s validity and the possibility of electro-mechanical impedance diagnostics of the payload.