Sensorial shaft - in-situ measurement of process-relevant state variables in frictional connections

• Applicants: Professor Dr. Günter Bräuer; Professor Dr.-Ing. Matthias Kreimeyer
• Subject Area: Engineering Design, Machine Elements, Product Development
• Term: since 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 511576481

With increasing technical advances and the resulting digitalization, classic machine elements (ME) are becoming a focus for the development of smart additional functions and digital networks. As part of that, sensor-integrated machine elements are intended to enable the digitalization of existing drive technology systems without expensive new investigations. The further development and integration of additional measurement functions for recording physical variables directly in the ME represents a promising approach here. Such a sensor integration offers considerable added value in product development and in condition monitoring in the field. Axles and shafts are the central ME for the transmission of forces and moments in drive systems. Shaft-hub connections (SHC) are essential for fulfilling their primary function. In this application frictionally engaged connections (press and clamp connections, clamping sets, etc.) being frequently used variants. The relevant variables (friction or normal force) for designing SHCs up to now, cannot be measured directly, but is determined indirectly from other variables. This inevitably leads to high deviations and uncertainties in the design. The need for meaningful state variables in operation makes it essential to determine various variables directly on the component. For this purpose, speed and vibration sensors are to be supplemented by a thin-film sensor system that enables in-situ-measurement of mechanical stresses, strains and temperatures on the component. The ME shaft as a central drive technology element is particularly suitable to carry the sensor system for the determination of extensive and reliable operating data. Existing design specifications can ensure a future standardized method for sensor integration in shafts without significantly affecting the primary function. Sensors based on multifunctional thin-film systems enable for the first time a precise spatially and temporally resolved determination of local characteristics and process parameters in direct component contact such as normal and shear stresses as well as temperature.

• DFG Programme: Research Grants