Design of an advanced composite shell for helicopter pilot helmets

Download

index.pdf

Date

2012

Author

Sünel, Ezgi

Metadata

Show full item record

Item Usage Stats

214
views

109
downloads

This thesis reports on a design study, conducted for an advanced composite helmet shell for helicopter pilots. The helmet shell is expected to provide a level of protection against low velocity impacts with its weight criteria. Therefore, ergonomy, light weight, and the ability to withstand low velocity impact became the main issues for this study. For this purpose, an experimental program has been developed including low velocity impact tests on specimens. The drop height, drop weight, specimen stacking sequences and size were constant parameters. Test specimens were produced using the plate size of 220x220 mm having different thicknesses. Specimen materials were aramid, carbon, and a hybrid form of these two. Thus, the parameters of the study were specimen thickness and the material types. The impact tests are carried out on a specially designed test rig. The design decisions are made in accordance with the results of the experiments. In compliance with the lightweight and manufacturing criteria, the hybrid specimen was selected helmet shell. For the purpose of ergonomy a geometric design was also conducted from headfrom sizes of Turkish Army by using 3D design software. After specifying the composite material, manufactured helmet shell was tested in another test rig according to the ANSI Z90.1.1992. For the requirement of the acceleration level 300g, the helmet shell design was found to be successful at seven different and critical impact points.

Subject Keywords

Mechanical Engineering.

URI

http://etd.lib.metu.edu.tr/upload/12614053/index.pdf
https://hdl.handle.net/11511/21377

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Computer aided engineering of an unmanned underwater vehicle Cevheri, Necmettin; Aksel, Mehmet Haluk; Department of Mechanical Engineering (2009) Hydrodynamic and thermal analyses performed during the conceptual design of an unmanned underwater vehicle are presented in this study. The hull shape is determined by considering alternative shapes and the dimensions are determined from the internal arrangement of components. Preliminary thermal analyses of the watertight section are performed with a commercial software called FLUENT to check the risk of over-heating due to the heat dissipation of devices. Performance of the proposed hull design is analyze...
Analysis of high-g camera support structure for crash test system Erdoğdu, Mahmut Gökhan; Gökler, Mustafa İlhan; Department of Mechanical Engineering (2009) Sled Crash Test System is one of the key elements in todays high safety vehicle designs. In the crash test systems, high speed imaging by high speed cameras is required. For the success of high speed imaging, high speed cameras should be well secured on the sled of the system which is being accelerated to high-g values to simulate vehicle crash. In this study, structural analysis of the high – g camera support structure for the sled crash test sytem which is available in METU-BİLTİR Center Vehicle Safety Un...
Design and analysis of fixturing in assembly of sheet metal components of helicopters Bayar, Fatih Mehmet; Gökler, Mustafa İlhan; Department of Mechanical Engineering (2007) Assembling of the compliant parts used in aviation industry is a challenging process. Assembly fixtures are quite important tools in this effort and widely used in industry. In fixturing of easily deformable sheet metal parts, besides restraining the rigid body motion of the parts, the possible deformations that may occur during the assembly process and the spring-back effect on the final product need to be taken in to consideration. In order to guarantee a successful assembling, in other words, to obtain t...
Investigation of wear behavior of aged and non-aged SiC-reinforced AlSi7Mg2 metal matrix composites in dry sliding conditions ÇELİK, YAHYA HIŞMAN; Demir, Mehmet Emin; KILIÇKAP, EROL; Kalkanlı, Ali (Springer Science and Business Media LLC, 2020-01-01) Metal matrix composites (MMCs) with their splendid mechanical properties have been specifically designed for use in fields such as aerospace and aviation. The presence of hard ceramic particles in MMC increases the hardness of the matrix product and decreases its coefficient of friction. Therefore, the wear resistance is improved. Moreover, the mechanical properties of these composite materials can be improved by applying heat treatments. In this study, AlSi7Mg2 MMCs with 15 wt% SiC reinforcement were produ...
On the non-linear vibration and mistuning identification of bladed disks Yümer , Mehmet Ersin; Özgüven, Hasan Nevzat; Department of Mechanical Engineering (2010) Forced response analysis of bladed disk assemblies plays a vital role in rotor blade design and has been drawing a great deal of attention both from research community and engine industry for more than half a century. However because of the phenomenon called ‘mistuning’, which destroys the cyclic symmetry of a rotor, there have been several difficulties related to forced response analysis ever since, two of which are addressed in this thesis: efficient non-linear forced response analysis of mistuned bladed ...

Citation Formats

E. Sünel, “Design of an advanced composite shell for helicopter pilot helmets,” M.S. - Master of Science, Middle East Technical University, 2012.