Mr Niedermeier, can you explain the Shaker technology in 1–2 sentences?
Well, essentially our test stand generates defined vibrations that are used to test components or vehicles for noise, defects, or environmental influences.
Which components or vehicles can be tested?
There are currently two different test stand systems. On the one hand, we have the vehicle shaker, with which we test all common cars, SUVs, vans and transporters.
With component shakers, it is possible to test individual components. The components themselves can vary greatly in size and weight. We are talking about centre consoles, displays, tanks - but also seats, complete door elements or sliding roofs. Depending on the requirements, we can adapt the test stand to the desired components.
What exactly distinguishes a vehicle shaker from a component shaker?
With the vehicle shaker, we use 2 or 4 actuators that are attached directly to the underbody of the vehicle.
With the component shaker, we have the option of stimulating the X-Y-Z axes individually or simultaneously. Normally, the corresponding actuators are docked to our carbon table on which the component to be tested is mounted.
Okay, that sounds interesting. Mr Niedermeier, how do you manage to generate the "defined vibrations" you describe?
In principle, such test benches have one thing in common. Electrical current is needed to excite the actuators from a power supply unit via a power amplifier.
For an accurate analysis, the power amplifier is controlled by very complex software and monitored by acceleration sensors on the test object.
Actuators come in a variety of designs. After a long development and testing phase, AKE chose the electromagnetic shaker because of its size, power and noise-free operation.
What tests are performed on the vehicles and components?
The most common test options are sine, random and driving profiles.
Sinusoidal testing, for example, allows a sweep from 5 to 100 Hz to be run with a defined acceleration and amplitude, and if a noise occurs, this frequency can be recorded for fault analysis.
Random tests offer the possibility to test a wide frequency range with random phase shifting of the individual frequencies. Since the frequencies in the freely definable profile all arrive at the test object simultaneously as a sine wave, noises can be detected very well.
With the driving profile, every recorded road trip/test track can be reproduced on the test stand, so that you have a test according to real conditions. For the tester, it is correspondingly more meaningful, as no wind, engine or driving noises are present during the test and any fault can be easily localized.
What advantage does a current AKE shaker have over the competition?
Our USP is, on the one hand, the compactness of the product. Our shakers can be integrated quickly and easily anywhere.
Another point that sets us apart is that our systems are very quiet. The quieter the system, the better it is for the analysis. And of course the performance is also convincing.
What developments have there been at AKE so far, Mr Niedermeier?
The development of AKE's own actuator and the associated electrical components, including the software. Then the docking units were developed and adapted for the respective car manufacturers and models. There are several variants of the docking units, such as hydraulic, electric or manual. Among others, there are also concepts for inline vehicle vibrators that are integrated into the production line. An important step was then to equip the entire system for climate change, e.g. for climate change tests from -40 to +60 degrees Celsius.
Both mechanically and electrically, we move with the times and bring these components up to the state-of-the-art technology.
In the area of software, a lot has happened from the beginning until today. The current software status is very complex and self-contained. This is especially necessary for the multi-axis control of several actuators.
For the Component Shaker, we currently have a specially designed carbon table instead of the earlier steel/aluminium constructions.
Now then. To what extent are customers involved in all the processes?
Due to the multitude of possible applications for our shaking systems, these are usually somewhat different for each customer. For some customers, among other things, something new has to be developed to meet the specifications. We are very flexible in this respect. All this would not be possible without a very good involvement of our customers.
So nothing is withheld from the customers, great! And if everything fits, do you carry out the tests directly at AKE?
That again depends on what our customers want. Of course, there is also the option of renting our premises and having the tests carried out in our in-house acoustic chamber. We prepare everything at AKE, operate all the equipment and help with the evaluation. The final evaluation itself is then up to the customer.
Since the subject of sound acoustics is becoming more and more important in all areas and is attracting more and more attention, most customers buy their own test stand from us. The shaker system is then manufactured in our factory as previously defined. After the pre-acceptance, the units are transported to the customer, set up there and the final tests of the units are carried out. Afterwards, our specialist trains the customer's entire staff in the operation, evaluation and maintenance of the test stand.
Wow, so you offer a complete service. Is it over after that?
No, of course it's not over after that. We offer follow-up training, for example if there has been a change of personnel or the first training took place some time ago.
We also offer our customers' maintenance contracts and calibrations, and when service cases arise, they are remedied as quickly as possible by remote maintenance or on site.
Updates of older shaker systems to the current status are also carried out.