Development and analysis of sensor-integrating feather-key connections

The aim of this study is a standardizable, sensor-integrating feather key (SiFK) that can measure the transmitted circumferential forces (and subsequently the torque) in a feather key connection without calibration for the respective application. The study proposes a new design for a feather key with a targeted stiffness condition. The geometry of the machine element is adapted by means of topology optimization so that a small number of strain gauges is sufficient to record the complete deformation state. The latter can then be used to determine the transmitted circumferential forces using a simple mechanical model. The work also includes efficient data reduction, subsequent wireless transmission, and energy harvesting using piezoelectric energy converters within the force direction. The required sensory and microelectronic components are integrated into the system in a space-neutral manner without impairing the main function of the machine element. The aim of the current work is to show a design kit to develop a SiFK to measure the circumferential forces and calculate the transmittable torque.