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Indian Journal of Fibre & Textile Research
Vol. 34, March 2009, pp. 59-63
Multiweave – A prototype weaving machine for multiaxial technical fabrics
Mário Limaa
Department of Mechanical Engineering, University of Minho, 4800-058 Guimarães, Portugal
Raul Fangueiro
Department of Textile Engineering, University of Minho, 4800-058 Guimarães, Portugal
António Costa
P & Maia Lda, Pisca, Creixomil, Guimarães, Portugal
Christien Rosiepen
Institut für Textiltechnik der Rwth Aachen , Aachen, Germany
and
Válter Rocha
Agilus Institute of Innovation in Information Technologies, Matosinhos, Portugal
Received 7 May 2008; accepted 25 June 2008
This paper reports the study on a multiaxial 2D interlaced woven structure able to provide specified strengths in four
different directions and the development of its manufacturing process. This structure is obtained by the insertion of
interlaced bias yarns at approximately 45º between the weft and the warp. Using the principle of the insertion and
interlacement of yarns in bias directions, a multiaxial weaving system has been designed which comprises the warp feeding,
bias yarns feeding and criss-cross insertion, shedding, incorporating one heddle, weft feeding and insertion, beating-up
mechanism, incorporating the reed, fabric taking-up and winding mechanisms. The designing of the system includes the use
of conventional weaving elements with completely new mechanisms or the modification of existing ones. The multiweave
prototype developed in this work is used to produce different types of directionally oriented structures using various types of
fibres (HT polyester, aramid, carbon and glass) and yarn counts. The important characteristics of this new fabric structure is
the criss-crossing between all four sets of yarns which increases the capability for supporting more severe mechanical loads
without failure, i.e. without delaminating. The strength-weight ratio is expected to increase, which can be very advantageous
for applications in the areas like composites for the aircraft and car industries as well as in marine textiles for boat and ship
building, which are the products subjected to severe stressing conditions.
Keywords: Composites, Multiaxial weaving, Multiweave, Technical textiles
1 Introduction
One of the most important characteristics of
technical textiles is the possibility of providing
specified strength in multiple directions. This
necessitated the development of multiaxial and
tetraxial fabrics. The use and impact of the multiaxial
fabric may be found in two different types of
products, namely (i) technical textiles, such as
composites for car and aircraft industry, conveyor
belts, inflatable boats, sails, boat hulls, air inflated
houses, geotextiles, wall coverings, sport devices,
tarpaulins, tents, grinding and lapping disks and for
many other applications on products that still use
traditional technology of gluing together several
layers of fabrics, differently oriented; and (ii)
garments, designed to be tear resistant with an
original texture, easily conformable and
dimensionally stable. They can be used for different
articles, such as military and protective clothing.
Although the application on conventional clothing
looks considerably out of the way, the possible
applications on tennis and other sports shoes and
some sportswear need to be further explored.
Several efforts to produce multiaxial interlaced
fabrics have been made in the past. Many European
patents have described the tetraxial1-3 and multiaxial4,5
structures and machines for their production. These
patents propose different solutions for the problem of
bias yarns feeding and criss-crossing, but none has
proved to be sufficiently good for the construction of
_________
aTo whom all the correspondence should be addressed.
E-mail: mlima@dem.uminho.pt
INDIAN J. FIBRE TEXT. RES., MARCH 2009
60
a reliable commercial multiaxial weaving machine.
Following the earlier work6, a new multiaxial woven
structure and the respective manufacturing process
have been developed. This kind of fabric is designed
to boost the reinforcement in bias directions by the
insertion of interlaced yarns between the weft and the
warp.
2 Materials and Methods
2.1 Materials
Fabric samples of different fibres were prepared
using the multiweave prototype. The fabric details are
given in Table 1 and the respective samples are shown
in Fig. 1, where the high regularity of the fabrics can
be observed.
Table 1—Composition of fabric samples
Sample
No.
Warp Bias Weft
1 PES 1100/2 dtex PES 1100/2 dtex Aramid 2200 dtex
2 PES 1100/4 dtex PES 1100/4 dtex PES 1100/4 dtex
3 PES 1100/2 dtex PES 1100/2 dtex Carbon 800 tex
2.2 Methodology
2.2.1 Model
A multiaxial woven fabric can be obtained by
interlacing 4 sets of yarns, the warps (blue), the wefts
(green) and other two sets of bias yarns at +45° and
-45° (red) as shown in Fig. 2.
2.2.2 Prototype
The main specifications for the design of the
limited scale multiweave development prototype were
established according to the available technical
capabilities. The resulting multiweave machine,
whose assembly design is shown in Fig. 3 (a),
comprises the elements, such as bias yarns feeding
system, mechanism for the criss-cross insertion of the
bias yarns, warping system, shedding system
incorporating the heddle, weft insertion system,
beating-up mechanism incorporating the reed, and
fabric taking-up system. The details of the fabric
formation area are shown in Fig. 3(b), where the shed,
the weft insertion needle and the special reed at the
beating position are shown.
2.2.3 Working Principle
The bias yarns are inserted from the bias beams
through a tension compensation device with a step-
wise movement in two very close parallel layers in
opposite directions by means of an appropriate
mechanism. The heddle and the reed are in their lower
and backward positions, out of the plane of the bias
yarns, allowing their free criss-crossing. The heddle
rises forming the shed and the warps interlace with
the bias. The shed is formed between the warp and the
two very close parallel layers of the bias yarns. A first
(false) beating takes place to clear the shed; this is
found necessary due to the reason that when the warp
yarns are raised by the heddle, they are partially held
up by the criss-crossing effect of the bias, preventing
from obtaining a clear shed. The weft yarn is then
inserted, interlaced with the warps and the bias yarns
as shown in Fig. 4; a second (real) beating operation
takes place which compacts the fabric at the same
Fig. 1—Multiweave fabric samples
Fig.
2
—
Geometric model of a multiaxial woven fabric
LIMA et al.: MULTIWEAVE – A PROTOTYPE WEAVING MACHINE
61
time when the heddle moves down to its rest position
closing the shed and holding the weft. The taking-up
mechanism advances one step and the fabric is
wound-up.
During the development process, all
synchronization has been achieved mechanically to
help getting a working prototype faster. Therefore, all
movements are mechanically driven from a main shaft
with the help of cam and intermittent mechanisms.
With all the mechanical systems sufficiently
developed, the required torque in the main shaft could
be measured. Consequently the most important
decisions, such as choosing the driving motor and the
frequency inverter, were made. The control system is
based on an ARM MCU microcontroller board with
embedded software designed to control the motor,
detect emergency stops using sensors and interface
with users. The main functionalities of the control
system include broken weft, warp, bias yarns
detection; strained weft detection; and speed
regulation. The main user interface options include
total fabric produced, fabric produced since the
machine was turned on or the last counter reset,
average speed (mm/s) since the machine was turned
on since the last counter reset, motor’s main shaft
speed in rpm, number of emergency stops, total
emergency's down-time and programming a certain
amount of fabric production.
2.2.4 Testing
As there are no standards available for multiaxial
fabric testing, a new procedure needs to be developed
in order to test the mechanical properties of the
multiweave fabrics. Therefore, conventional strip and
grab tensile tests were carried out.
3 Results and Discussion
Figure 5 shows the typical tensile behaviour for
1100/2 HT polyester multiweave fabric (sample
No. 2). This multiweave sample shows a quite
anisotropic behaviour once the mechanical parameters
vary according to the tested direction. As expected,
due to the double weft insertion, the sample gives
Fig. 4—Multiweave – detail of shed and weft insertion
Fig. 3—(a) Multiweave assembly design and (b) multiweave prototype showing the fabric formation area
Fig. 5—Typical tensile grab test on sample No. 2
INDIAN J. FIBRE TEXT. RES., MARCH 2009
62
higher tensile strength in the weft direction. Grab tests
or force-elongation tests for multiweave sample
comprise the following observations: (i) weft, bias
and warp yarns show a similar behaviour, which is
typical for a woven structure, (ii) differences in the
graphs are mainly due to the “double weft” or the
different materials used, and (iii) the weft always
seems to be less crimped than the warp or bias.
Figure 6 compares the tensile behaviour in the weft
direction for different materials, such as carbon,
aramid (Kevlar®) and polyester. As expected, the
carbon exhibits the higher tensile strength, followed
by aramid and then polyester. On the other hand,
polyester exhibits the higher elongation, while aramid
the lower one.
To keep the multiaxial structure fixed and to
produce a first multiaxial composite, a multiweave
fabric has been laminated in a polyester resin. It is
observed that when both fabric and resin are made of
the same material, the fabric structure does not
change. Figure 7 compares the tensile behaviour of
laminated and non-laminated multiweave 1100/2 HT
polyester fabric. As it can be observed that the
maximum applicable force is approximately ten times
higher for the laminated sample than that for the non-
laminated one. While the resin can only compensate
shear stress, tensile stress is compensated by the
fabric structure.
4 Conclusions
The multiweave concept was embodied in a
development prototype which proved its feasibility.
The design of newly developed multiaxial weaving
system is concerned with the characteristics of the
fabric structure, where there is criss-crossing between
all sets of yarns, which increases the capability for
supporting more severe mechanical loads without
failure, i.e. without delaminating. Simultaneously, the
strength-weight ratio is expected to increase, which
can be very advantageous for applications, such as in
the aircraft and car industries. Other important
application areas are marine textiles, such as
composites for boat and ship building, which are the
products having severe stressing conditions. The main
result is the multiweave prototype which is being used
to produce different types of directionally oriented
structures, using various types of fibres (HT polyester,
aramid, carbon and glass) and yarn counts.
The present limited scale development prototype is
observed as a learning tool from which much know-
how be acquired. Some mechanisms and details need
reviewing and optimisation. However, some aspects
need to be identified, e.g. while moving to a larger
fabric width (500 mm or 1000 mm), extra problems
will be raised by the extra complexity of the bias
yarns feeding system and the fabric being produced
presents a structure which is not yet very dense,
mainly due to the limitations imposed by the
relatively high bias pitch, hence more research and
development is required to find out the appropriate
solutions.
Industrial Importance: This study is expected to be
exploited by the technical textiles sector, mainly in
textile reinforced composites for high technological
applications, replacing with advantages the existing
techniques of using several layers of fabrics,
differently oriented, to achieve a higher isotropic
behaviour.
Acknowledgement
The authors are grateful to the European
Commission, VI Framework Programme for funding
project Multiweave COOP-CT-2003-1-508125. They
Fig. 6—Typical tensile behaviour in the weft direction for
different materials
Fig. 7—Typical tensile behaviour for 1100/2 HT polyester,
laminated and non-laminated
LIMA et al.: MULTIWEAVE – A PROTOTYPE WEAVING MACHINE
63
are also thankful to all the partners of the consortium
for their efforts during the development of
multiweave project.
References
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Tetraxial woven fabrics and tetraxial weaving machine
thereof, Eur Pat 0263392 A2 (Meidai Chemical Co. Ltd),
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2 Mamilano Dini, Tetraxial fabric and weaving machine for its
manufacture, US Pat 5351722 (D.I.M.A. Ricerche
Technologiche S.R.L, Drezzo, IT), 1994.
3 Mamilano Dini, Tetraxial fabric and machine for its
manufacture, WIPO Pat WO/2003/012184 A2 (Tetraxial
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4 Mood, Geoffrey Ingles, Mahboubian-Jones, Malcom G B,
Multiaxial Weaving, Eur Pat EP0571461 B1 GB (Short
Brothers PLC, Northern Ireland), 1992.
5 Mário Araujo, Mário Lima & Nuno Costa, Multi-axial fabric
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WO/2004/0059054 A1 (TECMINHO, Guimarães, PT), 2004.
6 Mário Araujo, Mário Lima & Nuno Costa, MULTITEX new
weaving concept for multiaxial fabric, TECNITEX 2001,
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