Constantly increasing energy costs and restrictive legal regulations make it necessary to consistently increase the efficiency in all types of machines and systems. As a result, damping influences are systematically reduced. In addition, mechanical structures are increasingly being designed in terms of lightweight construction, which further increases their sensitivity to vibration excitation. That is why it is urgently necessary to reduce vibrations of mechanical structures effectively and in a focused manner without significantly influencing the efficiency of the machine as a whole. The nonlinearities of the damping forces, which are often neglected in the design, open up great potential for realizing situation-dependent behavior without having to resort to active control and external energy supply.
In particular, dry friction with the inherent stick-slide transitions enables the realization of mechanical switching elements that can serve as basic building blocks for adaptable dissipative devices. Above all, the aim is to investigate how novel devices based on dry friction can be used for the targeted reduction of externally excited, parametrically excited, and self-excited vibrations. In addition to the analysis of the dissipative device itself, methods for determining an optimal configuration and spatial placement of these devices are also proposed. In order to achieve these goals, various devices based on four basic elements (elasticity, play, friction with possibly modulated normal force and spring with distributed friction) and their combinations are compared in terms of their effectiveness and their self-adaptive properties. In addition, analytical methods are being developed in order to be able to reliably evaluate the efficiency of these devices. Prototypes for the most promising concepts are manufactured and experimentally tested.
Contact: Prof. A. Fidlin, J. Aramendiz