Engineering of solutions for vibration challenges consists of several steps. Each of them needs different methods, for most steps, several approaches are valid. This work describes one efficient way to get from customer wishes over calculation methods and experimental results as far as the lifetime calculation. The example is an all-metal cushion used as a spring-damper system, that solves vibration problems of the suspension of an electrical drive for a commercial vehicle used in a city.
Metal cushions for vibration isolation are used where high dynamic stresses occur or the environmental conditions overwhelm rubber solutions. So, they are a perfect solution for vibration isolation in industrial environments as well as in railway, automotive and aerospace sectors. Additionally, the progressive stress-deflection behavior and the high damping offer advantages for a wide range of applications.
A Design of Experiment was necessary to define the parameters for an analytical equation to describe the nonlinear force-deflection characteristics of metal cushions. After calculating a valid metal mesh that satisfies the customer requirements, quasi-static measurement on prototypes is performed. Again, the nonlinearity is in focus as working point during the vibration stress. Confirming the calculated results, the lifetime of the cushions needs to be examined. Here, the comparison of the load, out of the calculated and measured results with the load from cushion specific S-N curves lead to reliable results.
The work will show the whole development process on the example of an electrical drive in a commercial vehicle that is running in a city loop.