Monitoring the integrity of filament-wound structures using built-in sensor networks

Abstract

Monitoring the integrity of filament wound composite structures such as solid rocket motors and liquid fuel bottles is important in order to prevent catastrophic failures and to prolong the service life of these structures. To ensure the safety and reliability of rocket components, they require frequent inspection for structural damages that might have occurred during manufacturing, transportation, and storage. The timely and accurate detection, characterization and monitoring of structural cracking, delamination, debonding and other types of damage is a major concern in the operational environment. Utilization of a sensor network system integrated with the structure itself can greatly reduce this inspection burden through fast in-situ data collection and processing. Acellent Technologies, Inc. is currently developing integrated structural monitoring tools for continuous monitoring of composite and metal structures on aircraft and spacecraft. Acellent's integrated structural monitoring system consists of a flexible sensor/actuator network layer called the SMART Layer, supporting diagnostic hardware, and data processing/analysis software. Recently, Acellent has been working with NASA Marshall Space Flight Center to develop ways of embedding the SMART Layer inside filament wound composite bottles. SMART Layers were designed and manufactured for the filament wound bottles and embedded in them during the filament winding process. Acellent has been working on developing a complete structural health monitoring system for the filament wound bottles including data processing tools to interpret the changes in sensor signal caused by changes in the structural condition or material property. A prototype of a filament wound composite bottle with an embedded sensor network has been fabricated and preliminary data analysis tools have been developed.

Effects of Elevated Temperature on Guided-wave Structural Health Monitoring

“…Thus, internal spacecraft structures become a potential application area for GW SHM using PZT-5A piezos. Some studies have examined GW SHM for cryogenic tanks (Blaise and Chang, 2001;Lin et al, 2003) and thermal protection systems (Yang et al, 2003;Derriso et al, 2004;Huang et al, 2005) in spacecraft structures. However, the experiments/simulations in these studies were restricted to room temperature (except in Blaise and Chang, 2001).…”

Design of a CMOS System-on-Chip for Passive, Near-Field Ultrasonic Energy Harvesting and Back-Telemetry

“…The comparison shows that the power dissipation of the proposed system is an order of magnitude lower than other systems. If a figure-of-merit (FOM) is defined as FOM = D Com S PZT × S Sys × P Sys (8) where D Com is the communication distance, S PZT and S Sys are sizes of PZT and system, respectively, and P Sys is power consumption of the system, the proposed design is two orders of magnitude superior to that of [16]. Note that the FOM metric could not be computed for other references in Table III, because some of the experimental parameters were not reported.…”

State-of-the-Art Developments of Acoustic Energy Transfer

“…There is another incident where the solution is required to communicate with the crews in a marine structure without affecting its configuration. Again, in a nuclear plant where the physical access is prohibited or in modern composite materials (carbon-fiber epoxy) that are used in military or aircrafts or packaging of food or beverage, for these cases AET is more appropriate due to its nonelectromagnetic features [37][38][39][40]. Furthermore, AET is not restricted to the frequency band and energy propagation direction.…”