Acceleration test bench with linear motors
How can dynamic tests and crash tests for products be carried out more easily and reproducibly?
This question was brought to ARADEX by a development team consisting of SCUS GmbH, Spezial Geräte Entwicklung GmbH and Fraunhofer AVV. Specifically, they wanted to investigate whether acceleration test benches of this performance class could be realized with electric drives.
First, the engineers of the involved companies analyzed the previous procedures of these two test methods.
The crash tests had previously been carried out mechanically over an inclined surface by SCUS GmbH, an accredited test laboratory. In this case, a test car loaded with a test object is accelerated to a defined speed, and the behavior upon impact is measured. However, double stacks in particular are at risk of tipping due to the 10 degree inclination of the test track. This problem does not occur with a horizontal setup.
The test method for dynamic tests is very complex and the testing procedure is difficult to reproduce; for this reason, there are no standardized methods for this yet in the area of transport suitability. Individual tests, e.g. the testing of anti-slip mats for truck pallets, are practically simulated in a truck. This test method naturally has the disadvantage that it is very complicated, and inaccuracies can easily creep in. It also cannot be reliably reproduced.
After a joint analysis, ARADEX developed the following solution: Four VECTOSYN® linear motors, driven by VECTODRIVE® inverters, move the test car. The test car can now be positioned as desired with the linear motors. This makes the handling of the VECTOSYN® setup much easier, since the car can travel to defined loading and unloading positions.
In the case of crash tests, the starting acceleration and impact speed are specified. The new setup easily maintains the required tolerances in regard to the impact speed despite occasionally dynamic loads. This also has considerable advantages over the existing cable pull or catapult solutions.
With existing systems, dynamic tests have either not been possible or only possible to a very limited extent. This now changes with the new linear motor solution.
As a result of the defined parameters of the control and the precise regulation of the VECTODRIVE® inverters, dynamic and crash tests can be carried out in a reproducible and much easier way. It is now possible to simulate crashes, hard braking and many other scenarios under laboratory conditions.
AIF funded research project KF 2217001WO9