ScienceDirect
IFAC-PapersOnLine 48-4 (2015) 117–122
ScienceDirect
Available online at www.sciencedirect.com
2405-8963 © 2015, IFAC (International Federation of Automatic Control) Hosting by Elsevier Ltd. All rights reserved.
Peer review under responsibility of International Federation of Automatic Control.
10.1016/j.ifacol.2015.07.018
© 2015, IFAC (International Federation of Automatic Control) Hosting by Elsevier Ltd. All rights reserved.
*Department of Mechatronics, Faculty of Engineering
Built Environment and Information technology
Nelson Mandela Metropolitan University, Port Elizabeth, South Africa
**Product Engineering, Volkswagen of South Africa, Uitenhage, South Africa
***Institute of Product and Process Innovation, Leuphana University, Lueneburg, Germany
Corresponding Author: mercorelli@uni.leuphan.de
Abstract: It is the desire of every motorist to drive an exquisite vehicle, so it is very crucial for players in
the automotive industry to keep on improving the quality of vehicles. While the interior components of a
vehicle are the most critical components to the overall durability and comfort of a vehicle, it is important
to guarantee the quality of these components. Vehicle interior components are usually made of plastic,
leather, fabric and painted components which can all be prone to quick ageing. Fading, cracking and
distortion are rife in vehicle interior components, and these effects are caused by natural factors such as
radiation, moisture and extreme temperature. This phenomenon is known as “weathering”. Tireless work
has been done over the decades to carry out weathering tests on automotive components in order to
address critical areas during the design process of the components. This paper explores one method of
carrying out weathering tests on automotive dashboards in which a metallic testing box is used to
simulate the conditions inside a vehicle. The main concern is that the temperature inside the test box can
go above the necessary testing range which causes test samples to be destroyed before sufficient data is
collected. A temperature control system was developed and installed to monitor the temperature inside
the box. Weathering tests are being carried out in extremely harsh environments; therefore both the
weathering test box and the temperature control system have to be robust. A solar-powered
programmable logic controller (PLC), which has the ability to withstand harsh conditions, was used to
monitor and control the system.
Development of a temperature controlled weathering test box to evaluate the life
cycle behaviour of interior automotive components
Tumai Zindove*, Theo Van Niekerk*, Thomas Wilm**, Paolo Mercorelli***
Keywords: Weathering, test box, Siemens PLC, ventilation, temperature control, greenhouse
1. INTRODUCTION
Weathering has been a critical subject for several decades
especially to the automotive industry. Several methods for
carrying out weathering tests are being used by automotive
companies as well as by companies specialising in material
testing. This paper focuses on the response of automotive
dashboards to global radiation. It is common for motorists to
park their vehicles in the sun for prolonged periods of time.
The effect of global radiation on interior automotive
components is often overlooked but it yields raging results
over the service period of a vehicle. Weathering tests can be
carried out by exposing test samples to natural conditions or
by simulating natural conditions in the laboratory (Atlas
Materials Testing Solutions 2001:5). When natural conditions
are simulated in the laboratory, it is called “accelerated
weathering”. The advantage of accelerated weathering is that
the test results are obtained quickly. However, accelerated
weathering cannot simulate the global radiation spectrum in
total (Atlas Materials Testing Solutions 2001:6). Accelerated
weathering is compatible with time-to-market constraints; it
provides test data quick enough to allow changes in the
product design process. However, it does not accurately
reproduce failure modes seen in real life (Haillant 2011).
In this paper, a low cost weathering testing method is
explored. A local automotive company is using two methods
to test interior vehicle components for weathering. The first
method is to park a vehicle in the sun such that the sun shines
through the windshield and degrades the interior components
while test data is continuously taken. The biggest shortfall of
this method is that the vehicle will be of little value at the end
of the testing period which makes this method costly.
To remedy the concern of using cars to carry out weathering
tests, the local automotive manufacturer has adopted the use
of testing boxes. The size of a testing box is such that it can
accommodate the dashboard of a passenger vehicle. The
dashboard is put into the testing box and it gets exposed to
maximum global radiation which shines through a glass
cover mounted at a convenient angle. These tests are being
carried out in areas with extreme levels of global radiation,
temperature and moisture. Atlas material testing solutions
also uses a similar technique but with integrated azimuth
tracking on the box to achieve maximum solar irradiance.
Atlas also uses fixed exposure racks for testing various
components (Atlas Materials Testing Solutions 2001:34). In
this paper a PLC was chosen as the most suitable type of
controller for this application.