Mürettebat oksijen maskeleri için tam otomatik, akıllı test sistemi tasarımı ve prototip imalatı
Fully automatic, smart test system design and prototype production for crew oxygen masks
Yazar: MUSTAFA TALHA KARAHAN
Danışman: PROF. DR. NURİYE LEMAN OKŞAN ÇETİNER YILDIRIM
İstanbul Teknik Üniversitesi / Fen Bilimleri Enstitüsü / Mekatronik Mühendisliği Ana Bilim Dalı / Mekatronik Mühendisliği Bilim Dalı
Derece: Yüksek Lisans, 2019
Konu: Mekatronik Mühendisliği = Mechatronics Engineering
Dizin: Otomatik test sistemi = Automatic test system

Özet:
Bu tez, uçaklarda pilotların acil durumlarda kullanmakta oldukları mürettebat oksijen
maskeleri için tam otomatik, akıllı test sistemi tasarımı ve prototip imalatı hakkındadır.
Bu maskeler kabin basıncı düştüğü zaman veya yangın gibi nedenlerden ötürü ortamda
zararlı gazlar bulunduğu zaman pilotun ve dolayısıyla yolcuların can güvenliğini
sağlayarak pilotların uçağı en yakın hava alanına indirebilecek kadar oksijen
alabilmeleri için tasarlanmış; pilot, mürettebat ve yolcuların can güvenliğini
sağlamaktadırlar.
Maskeler, periyodik aralıklarla maske kullanımını gerektiren ortamlar oluşturularak
test edilmekte; sızdırmazlık, hava-oksijen karıştırma özelliği gibi maskenin
fonksiyonel olarak çalışır durumda olup olmadığı maske tipine bağlı olarak kontrol
edilmektedir. Gerekli durumlarda ise maskelerin onarım ve yenilenmesi söz konusu
olmaktadır. Bu amaçla kullanılan mevcut test sistemi 40 yıl önce satın alınmış olup 3
parçadan oluşmakta ve tamamen manuel olarak yalnızca bir markanın maskelerini test
edebilmektedir. Yapılan testler insan faktöründen kaynaklanabilecek olan hatalara
açık olup bir maskenin testinin yapılması 6 adam/saat almaktadır.
Test işlemlerini yerli imkânlar kullanarak tamamen otomatize ve akıllı hale getirmek
ve piyasada en çok kullanılan 2 marka maskenin tüm maskelerini kabiliyete almak
adına bu tez çalışması yapılmıştır. Tezin sonucunda Mürettebat Oksijen Maskesi Test
Sistemi üretilmiş, test süresinde yaklaşık %83 oranında iyileştirme yapılmış olup test
edilebilen ürün sayısı 544'e ulaşmıştır. Mevcut test sisteminin kabiliyetinde olmayan
ürünler yeni Mürettebat Oksijen Maskesi Test Sistemi ile kabiliyete alınarak yurtdışına
teste gitmeleri engellenerek zamandan ve maliyetten tasarruf sağlanmıştır.

Abstract:
This thesis is about the design and prototype production of a fully automated,
intelligent test system for crew oxygen masks used by pilots in emergencies in
aircrafts.
These masks are designed to ensure the safety of the pilot and therefore passengers
when the cabin pressure drops or if there are harmful gases in the environment for
reasons such as fire, so that the pilots can get enough oxygen to bring the aircraft down
to the nearest airport. With high precision and advanced technical features, these masks
provide 100% oxygen when needed to conserve the amount of oxygen efficiently, or
when 100% oxygen is not required, they mix oxygen and ambient air to the pilot in a
certain ratio.
The pilot needs to breathe for the mask to deliver oxygen. Depending on the pilot's
breathing power, the mask delivers oxygen. In this context, the problems mentioned
in the importance and functional characteristics of the masks should be avoided.
Parallel to this requirement, the masks are tested at periodic intervals by creating
environments that require the use of masks, and the functionality of the mask such as
sealing and air-oxygen mixing is checked depending on the type of mask. If necessary,
the masks are repaired and overhauled.
Since the amount of oxygen to be used by the pilot is limited, the masks have a high
precision structure with advanced technical features that can mix the ambient air with
oxygen when necessary for using the oxygen amount efficiently. In order to ensure the
safety of crew and passengers, these highly sensitive masks shall be periodically tested
and maintained. For these reasons, mask test systems are used.
In the current system of our country's aircraft MRO companies, it is possible to control
the masks by measuring different parameters with three different machines. This
situation is insufficient in terms of usability and not ergonomic in terms of floor covering. In addition, performing the tests separately on three different devices
manually causes time and cost losses along with the reasons mentioned above and may
cause errors. The system currently used by MRO organizations in our country has lost
its ability to meet the requirements due to reasons such as manual usage, difficulties
in application, long test time and failure of testing with a single device. Imported
systems with superior properties are costly.
For the reasons mentioned above, in order to provide in-flight safety with high
reliability, maintenance and testing of oxygen masks used as emergency equipment by
pilots, had to be performed in a modern, reliable and high precision. In this ground, it
is aimed to design the modern test system and put it in the scope of the thesis and to
provide the transition to fully automatic structure in the test devices. Intertechnique
brand mask products as well as B / E brand mask products are targeted to be included
in the test capabilities.
It is aimed to shorten the completion time by making the test operation performed in
our country's aircraft MRO organizations on a single device automatically and to make
a system that can make more accurate measurement and minimize human error thanks
to its user-friendly interface.
The system, which has been designed and produced in this thesis, aimed to integrate
the test steps, which vary according to the mask type, in a single device. Since the
pressurized oxygen and vacuum to be applied to the masks differ according to the mask
type, the system will be able to automatically adjust the required values depending on
the choice of the end user thanks to the electromechanical control capability of the
system; thus, no further calculation is required. When the desired mask type is selected
on the device, values such as pressure, flow rate and vacuum values specified in the
maintenance instructions of that mask will be transferred to the automation system via
electronic communication protocol and the test process will be performed
automatically according to these values. In this way, it is possible to carry out a test
suitable for every type of mask, including the mask type that the current system cannot
test. In addition, our country is designed to be able to test the types of masks that are
not found in the fleets of airline companies.
All equipment used in this thesis, such as flowmeter, pressure gauge, oxygen analyzer,
and so on used to be communicated directly to the computer through the electronic system structure. This will eliminate factors such as the technician misreading or
overwriting the values; It is ensured that all test steps are carried out correctly until the
end of the test and that the test result report is presented at the end of the test process.
This will prevent the test result report from being filled with incorrect values.
As a result of the thesis, Crew Oxygen Mask Test System has been produced, 83%
improvement has been made in the test period and the number of products that can be
tested has reached 544. The products that are not capable of the existing test system
are equipped with the new Crew Oxygen Mask Test System, thus producing time and
cost savings.