Thermal and mechanical behaviour of an RFID based smart system embedded in a
transmission belt determined by FEM simulations for Industry 4.0 applications
Jan Albrecht, Rainer Dudek, Jilrgen Auersperg, Remi Pantou, Sven Rzepka
Fraunhofer ENAS, Micro Materials Center,
Technologie-Campus 3, 09126 Chemnitz, Germany
Abstract
The determination of the mechanical and thermo
mechanical behaviour of a UHF-RFID-based smart
system embedded in a transmission belt has been the goal
of the work reported in this paper. The complex bending
and thermal loads occurring during fabrication and
service are taken into account by finite element
simulations using ABAQUS standard™. In order to
achieve quantitatively correct results, dynamic
mechanical analyses using DMA Q800, DMA 2000+ as
well as thermo-mechanical analyses using TMA Q400
have been performed to characterize the behaviour of the
different materials. The results of the finite element
analyses match the experimental observations very well.
Therefore, recommendations for design optimization
could be deduced that prevent early and fatigue failures of
the smart system inside the transmission belt.
1. Introduction
Today's economy is changed by a fourth industrial
revolution. The computerization of the manufacturing
industry as seen in the past decades will now be
complemented by the connection of all machines, work
pieces, and systems to a comprehensive information
network covering the entire value chain. This 'Industry
4.0' approach brings unprecedented flexibility even to
mass production settings. Therefore, it allows the
combination of highest fabrication efficiency with a most
consequent individualization of the products according to
the actual needs of the customers.
Smart systems are the key hardware elements needed
for 'Industry 4.0'. They consist of sensors for signal
generation, nanoelectronics for signal processing and
communication, and are fabricated as highly miniaturized
modules, which can be directly integrated into the
respective machine parts or work pieces. Based on RFID
(radio frequency identification) technologies, data and
energy transfer can be organized wirelessly providing
autonomy and internet connectivity at the same time [1].
One example of such a smart system is the RFID
based transponder module (see Fig. I), which is integrated
into a transmission belt [2]. The belt is used in various
industrial and agricultural applications. The purpose of
the embedded smart system is to obtain and to
communicate all information needed from the belt at work
for optimizing its operation and for scheduling preventive
maintenance activities. Some similar work is shown in [3]
were a RFID tag is embedded into a tire. However, no
investigations have been reported so far dedicated to the
reliability of such an embedded system. In order to
provide the functionality, the embedded smart system
must reliably withstand all mechanical and thermal loads
that occur during fabrication and operation of the belt.
During fabricating, temperatures in excess of 180°C and
high pressures are applied. In consequence, a substantial
material shrinkage occurs during these vulcanization
processes so that large thermo-mechanical stresses are
induced into the smart system as well as at its interfaces
to the rubber composite material of the belt. During
operation, frequent cyclic bending as well as tension and
various pulse loads of high magnitudes occur. They cause
frictional self-heating of the belt with the consequence of
thermal expansion. The smart system must endure all the
thermal and mechanical stresses caused by this complex
cyclic dynamic load situation. These loadings also applied
to the implemented tag which can be reduced by
positioning the tag close to the neutral fibre of the belt,
which means close to the embedded cords.
RFID-tag
Figure 1: RFID-tag
components
FR4 substrate
To model the behaviour close to reality, appropriate
material parameters have to be determined by
experimental tests and transferred into material laws. The
behaviour of belts under bending loads has been
investigated for instance in [4].
The base material of the tag is FR4, a glass-reinforced
epoxy laminate with an orthotropic material behaviour.
The material properties could be used from former
investigations. The embedded die within the tag is
assumed as bulk silicon. All other components of the
smart system like the antenna and the electronic
components beside the die are neglected.
The ethylene-propylene-diene (EPDM) material
(elastomer) of the belt can be described by hyperelastic
material laws, which means that the material is nearly
incompressible under pressure and exhibits large strains
under tension. The behaviour is markedly nonlinear. To
describe this behaviour, various material laws with
different ranges of validity exist like NeoHook, Mooney
Rivlin, Odgen, Arruda-Boyce etc. (Fehler!
Verweisquelle konnte nicht gefunden werden.) [5-8].
978-1-4799-9950-7/15/$31.00 ©2015 IEEE -1/5-
2015 16th International Conference on Thermal, Mechanical and Multi-Physics Simulation and Experiments in Microelectronics and Microsystems
