From drawing board to motorway in just 7 months
No longer just steel as plastic parts come into
the reckoning for functional prototypes
Plastic components as well as steel components
can come into play as early as the first working prototype stage. It took
just 7 hectic months to get from the initial design drawings, via a working
prototype, to the finished Rivage sports car. For Tebis, this involved the
daily practical application of its scan data processing module and hybrid
and surface modelling.
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| Design drawings presented in Spring 2002 in Pforzheim. | The new Rivage crosses the finishing line after just 7 months (photos: Tebis) |
The contours of the model were repeatedly digitised and
processed further using Tebis software, further structural surfaces were added
and NC-programmes were generated for the production phase. For ITH, a customer
of Tebis, the car was an opportunity to demonstrate the quality and functionality
of a concept car. The project is a testament to sports car design, a lesson
in data management, a show car and concept car all rolled into one. It was
designed and built by ITH using Tebis software.
In the beginning
After the basic specifications were drawn up, various designs and studies
were developed for the Rivage starting in May 2002. An original clay model
was then made which led to two different prototypes being produced. The 1:4
scale model was quickly followed by a full-scale model which was finally released
at the end of July. At this stage a number of significant modifications were
introduced, which meant that a mere 18 weeks remained to convert the individual
components into technical models and finally to construct a fully road-worthy
vehicle.
From virtual to plastic reality
As the project progressed, Tebis used its CAD software for surface modelling.
Regular use was made of the visual digitisation systems produced by GOM GmbH
in Braunschweig/Germany, which delivered high quality net models in only a
few hours and which in each case were further processed using the Tebis CAD/CAM
system, scaled up, and supplied with structural surfaces. Using the Tebis
software’s CAM functionality, the package model, the 1:4 and full-scale
models and all of the model parts were rapidly and accurately reproduced on
the correspondingly large cutting machine.
The car takes shape
The last phase, which began with the digitisation of the 1:1 exhibition model,
was very important in terms the vehicle’s functional quality, the visual
impact made by its outer shell and the speed at which the entire vehicle could
be produced. The contours of the model were repeatedly digitised and processed
using the software, further structural surfaces were added and NC-programmes
were generated for the production phase. Based on this digitisation, the ITH
model builders and CAD/CAM users had to design and build each individual model
part to produce the various elements of the car body. The IHT model builders
were able to save a lot of time during the construction thanks to the Tebis
hybrid technology and the new surface generation software, which was already
at their disposal in prototype form. Thus, it took only 7 weeks to construct
all parts of the model, including devising the design, determining the sealing
structures and the functionality of hinges on the doors, the bonnet and the
boot as well as constructing all the elements responsible for strength and
stability. The nature of the process, where the original chassis specifications
were applied to the full-scale model, meant that the boundaries between plastic
reality and the virtual reality CAD-world were repeatedly crossed. It was
also an extremely interesting test environment for the CAD surface-modelling
module which will come onto the market in 2003.
After carrying out a special sandwich-laminate process, ITH produced the demonstration
car’s outer shell and all of its structural parts, so that these could
finally be installed and secured on the sports car.
And it all took just 7 months.
www.tebis.de
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| In the CAD-System, surface data have been scaled down to 1:4 and the underbody has been built on. | The complete package model is handed over to the designer in April 2002 | |
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| The individual model parts are constructed using Tebis (bodyshell and outer skin both scanned at the start). Shown here is the left side panel with door sill attached. |