Due to their advantages compliant mechanisms are very popular. However, they also have some disadvantages as well. Considering that for micromanipulators, which have macroscopic dimensions and a workspace typically in millimeter range, the disadvantages of compliant mechanisms are not as significant as the feasible benefits by reason of their advantages. For instance the range of notch hinges, which are typically used for micromanipulators, can be increased by the use of precision notch hinges with a narrow web thickness. Precision notch hinges are cut efficiently by wire electrical discharge machining. Therefore, flexure hinges are widely used in precision engineering applications.
Even though electrical discharge machining is a manufacturing process which is based on the thermo-physical material removal principle with less resulting mechanical stress, it still induces thermal stress on the component. It can be assumed that these influences have an impact on the component’s performance, in particular when the component has filigree structures like precision notch hinges. However, experimental studies on the fatigue of compliant joints are currently missing in research activities.
To analyze the manufacturing related influences on the performance of precision notch hinges a series of fatigue tests have to be performed. Thus, a suitable test bench for fatigue testing of precision notch hinges is designed and the used transmission mechanism is explained. Furthermore, the adjustment mechanism for the swivel angle as well as the adjustment mechanism for different loadings of the test specimens are discussed. Additionally, to avoid incorrect loading several design features are explained. To obtain reliable results, the filigree test specimens have to be positioned on the test bench reproducibly in order to ensure recurring test conditions. Thus, the positioning process is explained. In order to increase the number of tested notch hinges, several test specimens are tested simultaneously under the same conditions. Hence, a clear detection of the maximum number of load cycles of each test specimen is ensured by a detection mechanism. This contribution ends with the presentation of preliminary results of the life expectancy analyses of precision notch hinges and a brief discussion of the results.