JEC COMPOSITES MAGAZINE - Issue #104 - April/May 2016 - 44

fibre placement

Automated path planning and thermographic
monitoring for automated fibre placement
Therm-O-Plan utilizes path planning capabilities
within the process monitoring system of fibre
placement processes. A new methodology for
knowledge-based path planning is being developed
to reduce planning efforts, even for complex carbon
parts. In addition, the path planning process is
linked to a newly developed online thermal monitoring system for diverse fibre placement systems.

Fig. 1: Diagram of the superordinate solution "Therm-O-Plan" integrated in
standard process chain

DR.-ing. caRsten schmiDt,
heaD of ReseaRch gRouP
high PeRfoRmance PRoDuction of cfRP stRuctuRes,
klaas völtzeR, ReseaRch assistant,
ReseaRch gRouP high PeRfoRmance PRoDuction of cfRP stRuctuRes,
tRistan hocke, ReseaRch assistant,
ReseaRch gRouP high PeRfoRmance PRoDuction of cfRP stRuctuRes,
laRs WinDels, managing DiRectoR
of sWms systemtechnik ingenieuRgesellschaft mbh

utomated Fibre Placement (AFP) is one of the leading
manufacturing technologies when it comes to costeffective mass production of lightweight structures with
high-quality demands. As the reliability of automated production systems and the efficiency of process planning can certainly
be improved, not only the aerospace industry but also the automotive and other highly demanding lightweight-component
industries are pushing for developments.

A challenging task...
During the AFP process, pre-impregnated carbon fibre tows are
placed, preferably stress-free, on tool surfaces. As the complexity
of lightweight components tends to increase, tool surfaces are
becoming more complex as well. To fulfil the structural requirements for the desired carbon fibre-reinforced plastic (CFRP)

44 jec composites magazine / No104 April - May 2016

laminate, path planning is a very challenging, time-consuming
and strictly regulated manual process. Besides optimally chosen
tow courses, the process parameters affect the lay-up quality
decisively. For example, an insufficiently pre-heated surface or
changes in the compaction force within the lay-up process may
result in defects such as detachment of the material or deviations
in the planned and placed tow positions, particularly for complex
components. If not corrected, these anomalies might not comply
with the component design and corresponding structural requirements (design requirements). Usually, the machine operator is
in charge of quality assurance and conducts a visual inspection of
every single laid-up ply, which is time consuming and decreases
the productivity of the AFP process, as well. Furthermore, undetected defects will cause high repair expenses at a later point in
time or might even lead to, in some exceptional cases, scrapping
the entire part.

... becoming easier
The Therm-O-Plan project is a cooperation of the Institute of
Production Engineering and Machine Tools (IFW) at the Leibniz
Universität Hannover, Automation Technology GmbH (AT) and
SWMS Systemtechnik Ingenieurgesellschaft mbH (SWMS). The
aim of this project is to reduce the planning efforts for producing
lightweight structures through automated, optimized path planning, and to increase the reliability of automated fibre placement
processes as well as quality assurance using an online thermal
monitoring system. The final project outcome will be a state-of-theart process chain based on AFP processes, as shown in figure 1.

Table of Contents for the Digital Edition of JEC COMPOSITES MAGAZINE - Issue #104 - April/May 2016