Automated Systems in Fastener Technology - El Camino College

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Nov 2, 2013 (3 years and 7 months ago)

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Fasteners in the Aerospace Industry:

Automated Systems in Fastener Technology


Lecture Notes

Overview

This module, Automated Systems in Fastener Technology, is one of a series of modules designed
to present subject matter of interest to engineering and tec
hnology students. It covers topics
ranging from fully/semi
-
automated fastening manufacturing systems to aerospace fasteners
selection for a specific area or application in aerospace. Use of a specific fastener is driven by
important considerations such as
installation cost, weight, skin thickness, aerodynamic flushness,
corrosion, and many others.


Learning Objectives:

At the conclusion students will be able to



Demonstrate an understanding of different manufacturing processes used to install
fasteners



Des
cribe an
importance of considerations such as installation cost, weight, skin thickness,
aerodynamic flushness, corrosion, etc.,

in
aerospace fasteners selection



(Slide 2)

Fasteners in Aviation

Automated Systems in Fastener Technology



Fasteners Installa
tion in the Aerospace Industry

o

Fully/Semi
-
Automated Fastening Systems



Flex Track



Horizontal Rivet Injector



Snake
-
arm Robots



One piece Barrel Fastening



Automated Riveting Cell




2

(Slide 3)

Flex Track for Aircraft Manufacturing Processes



Traditionally, aircr
aft fastener drilling has been accomplished by using fixed drill
templates.



The Boeing Company has recently developed a portable, more flexible automated
drilling solutions, called Flex Track


(Slide 4)

Flex Track for Aircraft Manufacturing Processes



Flex
Track components:

o

Rails

o

Carriage

o

Add
-
ons / Modular Tool





3

(Slide 5)

Flex Track for Aircraft Manufacturing Processes



Flex Track is a modular two
-
axis numerically
-
controlled positioning system that
solves a 5
-
axis application.



(Slide 6)

Flex Track Vide
o on PPT

http://minift.com/movie.html



(Slide 7)

Horizontal Rivet Injector



The Low Voltage Electromagnet Riveter (LVER) is a 5
-
axis machines designed to
accurately fasten a vertically oriented wing skin and st
ringer. (Figure 1)


4




(Slide 8)

Horizontal Rivet Injector




5


(Slide 9)

Horizontal Rivet Injector



The skin side process tools and clamping foot (See Figure below)


(Slide 10)

Snake
-
arm robots for aircraft assembly

Compared to the automotive industry
, the aerospace industry has been slow to
introduce industrial robotics onto its assembly lines. Recently, however, there has been a
general move towards automation in order to increase
throughput and standardize processes.

The slow introduction of indust
rial robots into the
aerospace industry is largely due to the need for high accuracy
over large structures. For example, holes have to be drilled
within large structures with both high absolute and relative

6

accuracy relative to other holes and features of
the aircraft assembly.

Airbus has been researching low cost, highly flexible automation for several
years. However, tasks within rib bays and other low access areas found throughout
aircraft structures have remained practically inaccessible to automation
. Maneuvering an
industrial robot (above) through a small opening becomes an ‘eye of the needle’ problem
(right): it becomes practically impossible to use a conventional robot
-
arm to pass through
an access hole, for example, and conduct work within a wing
box.

Operating within a rib bay requires some of the capabilities of industrial robots,
e.g. the ability to place tools precisely, but other capabilities must be added to operate
within confined spaces. In particular it is necessary have a robot arm that
does not have
prominent ‘elbow’ joints. Snake
-
arm robots, having continuous curvature along their
length, are ideal for these applications.


Aerospace Applications

OCRobotics is working with Airbus UK and KUKA to develop aerospace robots
to deliver end e
ffectors packages capable of inspection,
drilling, sealing and swaging.

A snake
-
arm robot can be considered as an
additional tool that the larger industrial robot can
deliver or as an extension to the industrial robot. The
image on the right shows the ind
ustrial robot providing
the linear movement required for path
-
following with
the snake
-
arm robot attached as a forearm at the
industrial robot’s wrist. The snake
-
arm is also equipped
with a wrist and interface to attach different tools for
tasks such as sw
aging, sealing and inspection inside the
rib bay.






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The demonstrator

OC
Robotics has designed a prototype (left) which can demonstrate all the
required tasks inside a mock
-
up of a rib bay.
This shows a snake
-
arm robot mounted on a
Kuka

The demonstrato
r snake
-
arm has 10
segments, is 1800mm in length and 90mm in
diameter. The hollow bore is 15mm. The
complete system has 27 degrees of freedom.
This gives the arm the flexibility to ‘follow its nose’ into the
rib bay.

The snake
-
arm robot can follow a path
into the wing
-
box, either by joystick control or from a pre
-
determined
library of paths. The arm can then move in ‘Cartesian mode’
either by joystick control or automatically using visual
serving to ensure it is correctly aligned before beginning each task
. When applying
sealant, a camera on the tool piece tracks the line of the seam to ensure accurate and even
application.



Tools and applications

The purpose of a snake
-
arm is to introduce tools or sensors into
a confined space. In order to maximize th
e
benefit of the snake
-
arm’s path
-
following
capability, the diameter of the end
effectors’ envelope must be equal to or less
than the diameter of the snake
-
arm. The
length of the end effectors must be minimized, ideally to the
diameter of the snake
-
arm or
at least to less than 1.5x the
diameter.
In addition to these considerations, further
restrictions were placed on the
-
arm robot specification and the rib bay geometry.





8

(Slide 11)

Three interchangeable end effectors were designed by
OC
Robotics for the dem
onstrator:



An inspection tool
(
at right
) containing
several cameras with various functions


A swage tool
(pictured right) to swage a
rivet and direct the removed section into a
collection area


A sealant tool
(pictured right) incorporating
a standa
rd sized sealant cartridge and nozzle, with cameras to allow automatic
orientation of the tool piece to the seam.


Other potential aerospace applications

The demonstrator was designed to complete only the specific processes that were
identified by Airbus

as being important in the manufacture of certain aircraft.

However, a snake
-
arm robot is a method of delivering any tool or sensor package
into restricted access sites. As such, it is expected that these robots will be used for in
-
service inspection and,

potentially, repair as well as production.

Snake
-
arm robots can be used as stand
-
alone systems or in cooperation with
industrial robots. As a standalone system a snake
-
arm robot is a steerable bore scope.
OC
Robotics is conducting research to reduce the d
iameter of a snake
-
arm to make it
suitable for engine inspection and repair.

Other tasks that could be considered for aircraft manufacture include: deburring;
drilling; extraction of foreign bodies; installation of components; insertion of wire looms;
las
er welding; leak detection; non destructive testing; nut
-
running; painting; removal of
liquids, gases or particulate matter; removal of swarf; and thermal imaging.

Snake
-
arm robots enable different approaches to be considered. In the long term, this
techn
ology may allow aircraft designers to consider structures that cannot be built with





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(Slide 12)

Snake
-
arm Robots




Snake
-
arm Robot on an assembly line, reaching into the wing box.

(Slide 13)

One piece Barrel Fastening



The one
-
piece
-
barrel (OPB) fuselage

design offered a new challenge to fastening
equipment assembly cell.




10

(Slide 14)

One piece Barrel Fastening



To accurately locate fasteners relative to the frames was to base fastener positions
relative to tack fastener positions for automatic fasteni
ng.



The tooling that supports the barrel would rotate the barrel through 360 degrees of
rotation.





(Slide 15)

Automated Riveting Cell for A320 Wing Panels



The machine is based on existing Electroimpact technology but incorporates
numerous design modif
ications to process tools, fastener feed hardware, machine
structure and the control system.


11

(Slide 16)

Automated Riveting Cell for A320 Wing Panels



Improvements on the machine:

o

Rivet Feed to EMR

o

Lockbolt cycle time

o

Fastener Buffer

o

Simplified Collar Fee
d System

o

Machine Structure Improvements

o

Control System Improvements


(Slide 17)

Aerospace Fasteners Selection



Many factors affect the selection of a specific type of fasteners for a specific area or
application in aerospace.



Some important consideration ar
e:

o

Installation Cost

o

Rate

o

Weight

o

Shear, allowable

o

Skin thickness

o

Aerodynamic flushness

o

Noise

o

Corrosion












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Review of

Fasteners in the Aerospace Industry:

Automated Systems in Fastener Technology


At the conclusion students should be able to



Demons
trate an understanding of different manufacturing processes used to install
fasteners



Describe an
importance of considerations such as installation cost, weight, skin thickness,
aerodynamic flushness, corrosion, etc.,

in
aerospace fasteners selection


Refe
rences

Arabe, C. K., (2003). The Fastener Industry: The Past, Present & Future. Industrial Market
Trends. Retrieved March 23, 2008, from
http://news.thomasnet.com/I
MT/archives/2003/08/the_fastener_in.html?t=archive
.


Rice, M. (2004). MIG welding


The basics and then some. Retrieved March 23, 2008, from
http://www.thefabricator.com/A
rcWelding/ArcWelding_Article.cfm?ID=929


Cary, H. B., Kalpakjian, S., Steven, R. S., Weman, K., Craig, E., (1991). Gas metal arc welding.
Wikipedia: The Free Encyclopedia. Retrieved March 23, 2008, from
http://en.wikipedia.org/wiki/Gas_metal_arc_welding


Cary, H. B., Minnick, W., Weman, K., Messler, R.W. (1996). Gas tungsten arc welding.
Wikipedia: The Free Encyclopedia. Retrieved March 23, 2008, from
http://en.wikipedia.org/wiki/Gas_tungsten_arc_welding



(2008). What is TIG Welding? Miller Electric Manufacturing Company. Retrieved March 23,
2008, from
h
ttp://www.millerwelds.com/education/tech_tips/TIG_tips/


Blunt, J., Nigel, C. B., Cary, H. B., Scott, C. H., Hicks, J., Kalpakjian, S., et al. (1999). Welding.
Wikipedia: The Free Encyclopedia. Retrieved March 23, 2008 from
http://en.wikipedia.org/wiki/Welding


Herald, C. Welding Joint Geometry and Welding Symbols. LEE CO. ATC. Retrieved March 23,
2008 from
http://www.aws.org/educators/Lib
rary/0000/000060.ppt


Durante, C. (2004). Friction Stir Welding (Aerospace). SAE Forums. Retrieved March 23, 2008
from
http://forums.sae.org/access/dispatch.cgi/stirweld_pf


Thrall, E. W
. (1977). Primary Adhesively Bonded Structure Technology (PABST). Douglas
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http://www.aiaa.org/content.cfm?pageid=406&gTable=japaperimportPre97&gID=58825


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Aircraft Primary Structure Adhesive Bonding Development. Lockheed Martin Aeronautical
Systems, etc. Retrieved March 23, 2008 from
http://web.archive.org/web/*/http://www.onr.navy.mil/sci_tech/3t/mantech/docs/success_stories/
t/PEO(T)_AdhesiveBonding_120805.pdf



Düsseldorf. (2004). Bo
nding/Adhasive Textbook. The Adhesive and Sealant Council, INC.
FEICA Education Materials. Retrieved March 23, 2008 from
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Moody, J. (2007). Adhesive Overview.
Zeta Scientific LLC. Retrieved March 23, 2008 from
http://chapters.sme.org/c098/files/Download/Adhesives%20Overview.ppt


Adhesive. Wikipedia: The Free Encyclopedia. Retriev
ed March 23, 2008 from
http://en.wikipedia.org/wiki/Adhesive


Smith, C., Segui, W. T. (1990). Rivet.
Wikipedia: Free Encyclopedia. Retrieved March 23, 2008
from
http://en.wikipedia.org/wiki/Rivet


SpaceTec Certification Readiness Course. Applied Mechanics. Retrieved March 23, 2008 from
http://www.spacetec.org/docs/AppliedMechanics.ppt


Green,

R., Roe, J. W., Wilson, B. A. (1916). Screw thread. Wikipedia: Free Encyclopedia.
Retrieved March 23, 2008 from
http://en.wikipedia.org/wiki/Screw_thread#ISO_standard_thread
s


Bolt Science. Information on Screw Threads. Retrieved March 23,2008 from
http://www.boltscience.com/pages/screw3.htm


Threaded Fasteners. Retrieved March 23,2008 from
http://pioneer.netserv.chula.ac.th/~kjirapon/PowerPoint/Chapter%2011%20Thread%20Fastener.
ppt



http://www.pilotfriend.com/experimental/build_8.htm