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The Advanced Composites Repair Analysis Tool (ACRAT) has been under development for the USAF Advanced Composites Program Office under an Ogden ALC Design Engineering Program (DEP) Contractual Engineering Task (CET) Order. ...The objective has been to develop Beta versions of this computer aided composite repair design and assessment engineering tool following the provisions and procedures of the ASTM Standard E 1340-90 (Reference 1). ...Four (4) customized database schemas (M&P, Aircraft Design, Composite Repair, Component Test) were designed and sufficiently populated to evaluate each data model's ability to meet specific ACRAT system requirements.

A series of carefully selected tests were used to isolate the coupled influence of various combinations of the number of facesheet plies, impact energies, and impactor diameters on the damage formation and residual strength degradation of sandwich composites due to normal impact. The diameter of the planar damage area associated with Through Transmission Ultrasonic C-scan and the compression after impact measurements were used to describe the extent of the internal damage and residual strength degradation of test panels, respectively. ...Employing the methodology outlined here, it may be possible to tailor sandwich composite designs in order to obtain enhanced damage tolerance characteristics over a range of expected impacts.

In this paper, the above-mentioned probabilistic approach is applied for the analysis of a stiffened composite panel of an aircraft and its acoustic performances in terms of transmission loss. The frequency dependent transmission loss of this composite structure is optimized with respect to two ply thicknesses and four material properties in order to obtain a high transmission loss throughout different frequencies for good acoustic insulation. ...The frequency dependent transmission loss of this composite structure is optimized with respect to two ply thicknesses and four material properties in order to obtain a high transmission loss throughout different frequencies for good acoustic insulation. ...The structural behavior of the composite panel is calculated with the Finite Element Method, while the acoustic performance is predicted with the Boundary Element method.

This document describes a standard method to collect and report dielectric data for the purpose of monitoring or studying the cure of composites.

Composite materials are used to design driveshafts when significant weight savings are sought or when traditional materials cannot be used. ...Driveshaft design consists of selecting the number of intermediate supports, the shaft diameter and wall-thickness. With composites, the choice of fibers and fiber orientation are additional variables to be used for optimization. ...This paper review the basic theory necessary for designing composite driveshafts and optimum design procedures are discussed.

The performance benefits of fiber reinforced composites are now widely accepted and because of the critical importance of weight reduction throughout the aerospace industry, technical progress in many areas is rapid. ...Laser welding of specific composite combinations is demonstrated and mechanical test results are presented. These results show that good weld strength can be achieved at realistic speeds using standard laser optics.

Use of new alloys, 2. greater use of “near-net-shape” parts, 3. employment of low cost alloys modified by ion implantation or by laser glazing, and 4. greater use of fiber reinforced plastics, thermoformable plastics, reinforced stampable plastics and fiber reinforced metal matrix composites.

This paper develops a robot automatic drilling system for processing the titanium alloy, aluminum alloy and laminated composites component of aircraft. The accurate robot drilling system is comprised of ABB IRB6640-235 robot, drilling end-effector, end-effctor control system and vision system.

Composite materials, pioneered by aerospace engineering due to their lightweight, strength, and durability properties, are increasingly adopted in the high-performance automotive sector. ...Besides the acknowledged composite components’ performance, enabled lightweighting is becoming even more crucial for energy efficiency, and therefore emissions along vehicle use phase from a decarbonization perspective. ...Research on different carbon footprint sources reduction is increasing, and even the European Composites Industry Association is demanding the development of specific Design for Sustainability approaches.

Using Thermal Simulation to Model the Effects of Wind on the Mars Curiosity Rover Quality and Validation of Digital Designs for Aerospace and Defense Scaling LiDAR Optical Payloads from Drones to Miniature UAVs Using Sintered Fiber Metal Composites for Aircraft Acoustic Attenuation GaN Breaks Barriers RF Power Amplifiers Go Wide and High Test System Ensures Flawless Performance of Military RF Devices The Impact of Video Compression on Remote Cardiac Pulse Measurement Using Imaging Photoplethysmography Remote physiological measurement technique leverages digital cameras to recover the blood volume pulse from the human body.

Environmental Control Systems (ECS) ducts on airplanes are primarily fabricated from aluminum or thermoset composites, depending on temperature and pressure requirements. It is imperative to fabricate lightweight, cost effective, durable, and repairable systems with minimal tooling.

Bell Helicopter Textron has used fiber reinforced plastic materials in many applications since the earliest appearance of these materials. An overview of past, present and future usage is presented. The discussion includes examples of fuselage, control system, main rotor, energy attenuator and engine cowling/firewall applications.

It was determined that the modal frequencies and damping ratios are affected by the fiber orientation in the composite panel. The transmission loss of composite panels is compared with that of aluminum panels of equal critical shear load. ...The noise transmission loss characteristics of 28 flat, fiber reinforced, composite panels and 4 aluminum panels, with dimensions of 24.1 cm by 40.6 cm, have been experimentally investigated in the NASA Langley Research Center noise transmission loss apparatus.

Nowadays LHP (CPL) is widely used in thermal control systems for space and ground applications. Wick structure is a key element which plays at least two roles: capillary pump to move a working fluid from condenser to the heat loaded zone and thermal and hydraulic breaker between liquid and vapor in LHP (CPL). This paper is devoted to the R&D of LHP with advanced low-cost ceramic wick structure, which has a high capillary pressure head and low thermal conductivity. First set of tests with acetone as a working fluid was done in Porous Media Laboratory, Minsk, Belarus to prove the possibility to use such kind of wick in present and future designs of LHP (CPL).

Microsatellite BIRD (Bispectral InfraRed Detection), mass 92 kg, sizes 550×610×620 mm was put on October 22, 2001 in a sun-synchronous orbit. The passive thermal control system (TCS) provided a temperature range of −10…+30 °C for a payload. It is assembled from precision optical instruments and housekeeping equipment with average power about 35 W. In the observation mode a power consumption peak of 200 W is occurred during 10-20 min. The TCS ensured a thermal stable design of the payload structure and is realised by heat transfer elements (conductors and grooved heat pipes), which thermally connected the satellite segments, two radiators, multilayer insulation and low-conductive stand-offs. Three years in space have brought an enormous volume of telemetric data about thermal performance of the TCS, based on information from temperature sensors, power consumption, attitude relative to Sun and Earth.

Joining advanced composite materials is one of the greatest obstacles to proliferating their use in aerospace structures. ...Another hindrance is the high cost of manufacturing advanced composite structures using conventional methods. The present trend in both the automotive and aerospace industries is lighter weight, energy efficient structures. ...In the aerospace community, the use of advanced composite structures has the potential for weight reductions of 35 to 40 percent as compared with the use of conventional aluminum alloys.

Such metal nanoparticle-fluid composite materials are referred to as nanofluids and their use as coolants has the potential to reduce the weight and power requirements of spacecraft thermal control systems.

The vehicle features graphite/epoxy composite monocoque construction, a high power-density permanent magnet electric motor, a mechanical/hydraulic continuously variable transmission, nickel-hydrogen satellite batteries, and a composite leaf spring suspension. ...The vehicle features graphite/epoxy composite monocoque construction, a high power-density permanent magnet electric motor, a mechanical/hydraulic continuously variable transmission, nickel-hydrogen satellite batteries, and a composite leaf spring suspension. The race strategies and tactics of energy management are optimized through use of a computer code which simulates the vehicle under race conditions.

Future aircraft hydraulic circuits must become more energy efficient to meet expanding power requirements such as thrust vectoring, with a reduced airframe heat dissipation capability associated with composite materials and sustained supersonic speed operation. The microprocessor controlled pump described herein acts as an energy management controller.

Emphasis will be placed on design and manufacturing decisions relating to the extensive use of composite materials throughout the aircraft.