Simulation und Versuch
Simulation und Versuch

Flexible Shaker


We carry out realistic tests on different components as it would be the complete auto-system with our 
invented and patented Fexible testrig which works on a hydraulic shaker system. 

Our Invention serves to analyse the interaction between a bodywork
and the component which is to be tested (especially the roof system).


For the Process:



The body of a cabrio is recreated as a lead frame with adjustable elements.
This recreation is our Flexible Shaker Type 1, short = FSB1
designed specially for Cabrio related components.


For all other Car-types ( limousines, SUVs, compact cars,...,.)
We have created the (FSB2).
The main focus of the testing-process with both of our testrig benches lies in
the testing of the components in the right dynamic surroundings.
We ensure that the results of our test bench match with the results of later performance
of the tested components in real situations.


We like to demonstrate you the basic idea of our FSB using convertible roofs:



developement of the body and developement of the roof system are usally happening independently of each other.
due to that, suppliers and oems (vehicle manufactors) often mainly focus on their own system.
That causes a lack of concentration on the connection area of both opponents often leading to
deficiencies in the BIW-roof connection

Moreover, mostly the dynamic design takes place in a rigid environment ("rigid block" or body cutouts),
which leads to a falsification of the results.

Natura-frequencies against rigid constrains are usally in the range of 20-30Hz and
normally they collapse with global modes, which lay much deeper.
Due to that, different data has a different output despite doing the same stimulation
on the component (e.g. by measuring the roof-mainbearing).




in our opinion, a test bench for convertible roof systems has to meet the following requirements:

The first mode shapes should correspond to the overall vehicle.
The first torsional and bending natural frequency should be adjustable in the frequency band from 12 to 25 Hz.
The construction modes (e.g., pitch, roll, yaw) should be below 7 Hz.
The torsional stiffness and the trimmed body mass should correspond to the real vehicle.
Installation of all roof systems should be made possible.
The test bench should be able to bear several vehicle lives.
The test bench should be inexpensive and easy to maintain.
The experiments should be feasible on a standard four-stamp system.




Through continuous development, our test bench is able to cope with all requirements and realistically represent complete vehicle conditions and
thus check abration areas (whitemarks) in the storage and NVH problems. In addition, further tests can be carried out:

NVH and S & R behavior in the climate chamber
Endurance runs
Effects of the roof section of panorama roofs on the body stiffness
Development of roof systems with the least possible stiffness decrease

For these tests, the two self-developed test stands FSB1 and FSB2 are ready.


The basic frameworks of the two test bench concepts can also be used for other components:

Basically, it makes sense to consider all assemblies whose static and dynamic behavior changes under overall vehicle conditions.



In addition to convertible, sliding and panoramic roofs interesting examples are:

  • Doors and flaps
  • instrument panels
  • steering systems
  • Spoiler (depending on integration concept)
  • seats

The test bench should enable suppliers in particular to develop their products under realistic assumptions.
Without relying on mostly rare and expensive bodies, the concept can be reliably secured in the first stages of development.

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