JEC COMPOSITES MAGAZINE - Issue #147 - September/October 2022 - 23

Additive manufacturing
Towards a digital twin of UD tapes
for automated fi bre placement
Testing
Optical data rectifi cation and ML-aided impedance
analysis for quality assurance of carbon fi bre
23
25
additive manufacturing MANUFACTURlNG
Towards a digital twin of UD tapes
for automated fi bre placement
With the ongoing trends in the Industrial Internet of Things (IIoT), the
question arises if digitization benefi ts automated fi bre placement (AFP)
in making it even more cost and resource effi cient. Fraunhofer IPT is
developing digitization strategies for different types of UD tape materials
to facilitate and optimize processing.
MaLena schuLz, Group Leader
phiLip JonGeBLoed, Research Fellow
eiMantas surviLa, Research Fellow
heiko BauMann, Research Fellow
henninG Janssen, Head of Department
Fraunhofer Institute for Production Technology
IPT, Aachen
T
he growing amount of application cases
proves that the Industrial Internet of
Th ings (IIoT) and Industry 4.0 concepts
are a solution to complex manufacturing
environments, whether the fl exible series
production of customized products or the
complexity of the manufacturing process itself
require novel perspectives. Th ese concepts
imply that equipping each production step
with its own cyber-physical production system
(CPPS) allows a self-suffi cient reaction
and optimization. Continuous data acquisition
helps enabling data-driven modelling
strategies for complex processes and fusing
the physical with the virtual world.
Application cases
Application cases in production engineering
have shown the successful and benefi cial
integration of CPPS, such as for fi ne blanking,
heavy plate rolling or injection moulding [1].
In the case of AFP, novel sensors are implemented
to acquire data about defects such as
gaps and overlaps during processing [2].
Studies conducted by Fraunhofer IPT provide
insights into how data can facilitate processing
conditions for AFP with in-situ consolidation
of thermoplastic tapes ([3-5]). Especially in the
latt er case, process conditions can strongly vary
due to the local application and tailoring of heat
with respect to the specifi c material and part geometry.
Th ese studies indicate the necessity to
combine all assessed data into a holistic digital
representation of the composite part.
Digitizing the AFP process
When digitizing the AFP process, the knowledge
about the incoming tape is crucial as it
provides information on how to process the material
and how to adapt the process parameters.
For thermoset materials, knowing the material's
constituents, length, width and thickness plays
an important role in determining an accurate
processing strategy. Geometrical consistency
in terms of thickness and width is required
to avoid gaps, overlaps and local thickness
variations of the laminate. In the case of thermoplastics
and AFP with in-situ consolidation,
it is even more important to characterize the
tape. Th ermoplastic tape bonding is governed
by autohesion and intimate contact formation.
Appropriate temperature conditions in the
process zone and application of the right
pressure are crucial. When radiation-based
heating systems such as diode lasers are used,
material properties such as heat capacity, thermal
conductivity and absorption and refl ection
infl uence the local heating process of the UD
tapes. Th e roughness and waviness of the tape
are also of high importance since they have a
signifi cant infl uence on the intimate contact
formation. Th is information is decisive to produce
fully-consolidated, high-quality laminates
N°147 September - October 2022 / jec composites magazine
23
MANUFACTURlNG
JEC COMPOSITES MAGAZINE - Issue #147 - September/October 2022

Table of Contents for the Digital Edition of JEC COMPOSITES MAGAZINE - Issue #147 - September/October 2022
