Munich. The BMW Group has introduced computer
tomography (CT) into prototype development, production and analysis –
a first in the automotive industry. Thanks to this technology, the
full range of vehicles, from MINI to Rolls-Royce, can now be
quality-controlled even in the early stages of development. Scans are
performed by four robots which move around the outside of the
prototype to produce several thousand cross-sectional images. These
are then used for detailed examinations of innovations, new materials
and bonding technologies. Until now, vehicles have had to be
dismantled for analysis, but CT allows checks to be carried out with
the vehicle completely intact. The new X-ray system is based in the
BMW Group Pilot Plant in the Research Innovation Centre (FIZ) in
Munich, at the intersection between Development and Production.
Udo Hänle, head of Production Integration and Pilot Plant: “The use
of this state-of-the-art computer tomography system is a major step
forward for us as it will help us to improve the quality of our
products even further. We can now analyse our prototypes in minute
detail without having to dismantle them first. The new system allows
us to examine our vehicles in a way that wouldn’t be possible with
conventional, static computer tomography systems. Ultimately, this
will enable us to integrate new technologies into a series vehicles
even faster.”
Analysis of internal structures
Michael Koch, head of Material and Process Analysis, adds: “We’ve
been using CT and X-ray scans to check vehicle parts for many years,
but this latest system takes quality assurance to an entirely new
level. We can now analyse our vehicles right down to micro-metre level.”
This degree of detail is required for a range of reasons, for
instance to check welds and punch screw connections, and to verify
body condition before and after painting, where extreme temperatures
can affect adhesive bonds. Findings from the scan are then used as a
basis for making targeted modifications to series production.
The scan itself is performed by four coordinated robots. Once the
vehicle is in position in the system, the robots move around it.
Working in pairs, they send X-rays through it and across to their
counterparts. The data they collect is then put through a specially
developed computer program that calculates a multi-layered,
three-dimensional image. This forms the basis for a detailed analysis
of the internal workings of the vehicle, offering information on
objects as small as 100 micro-metres – approximately the width of a
human hair.
Engineers are currently carrying out research to establish how far
Artificial Intelligence might be used to evaluate findings. By
processing large amounts of data, the software can learn the many
different patterns that occur, link individual items of data, and
gradually evaluate findings automatically.
Two years of development work
BMW Group engineers and the Fraunhofer Development Centre for X-Ray
Technology (EZRT) spent two years developing the new system, which is
the only one of its kind in the automotive industry.
Philipp Janello, project manager at the BMW Group, explains: “Working
with X-ray specialists and plant engineers, we were able to enhance
the software of the test system with the help of comprehensive test
measurements carried out on the vehicle body.” The result is a
customised system that meets the requirements of the BMW Group.
Consumption and Emission Data.
BMW i8 Roadster:
Combined fuel consumption 2.1 l/100 km;
confined electricity consumption 14.5 kWh/100 km; combined CO2
emissions 46 g/km.
(All figures based on EU test cycle using standard tyres).