Datenpaket: Measurement and Characterization of Evolving Prototypes of Sensor-Integrating Bolts for Multi-axial Force Measurement

Sensor-integrating bolts integrate sensory functions into existing machine elements and provide in-situ data acquisition. Measurement data of three iterations of sensor-integrating bolts for multi-axial force measurement is presented here, operated in a universal testing machine with axial and bending loads.
Three strain gauge half bridges, sampled by a state of the art data acquisition system GSV4 of ME-Systeme and a completely integrable measurement chain with BLE interface (FLECS) are used.

Three testing objects of sensor-integrating bolts are operated and measured: V1 (named zylDms_2), V2.1 (named 4p_1) and V2.2 (named 3p_3). The loading was tensile axial (named "zug"), bending (three point, named "Biegung_3p") and tightening (named "anziehen"). The loading is based on ISO376 with three preload cycles and three stepwise loadings with four or eight steps each. The orientation of the bolt within the testing machine completes the filenames. For axial loading it was either only one orientation or 0°, 120°, 240° and for bending 0°, 60°, 120°, 180°, 240°, 300°.
The data are saved as MATLAB files (.mat) and formatted as structs. Each struct has the sub-structs signals (raw data), signals_postprocessing (offset and sign adjusted, median filtered with window size 5), time (timestamp vector) and metadata (sample frequency and more).
ch1, ch2, ch3 are three strain gauge signals within the bolts. ch4 is the force measuring washer (only for "anziehen", tightening, not connected for the other load cases), which is calculated to Newtons in postprocessing using the sensor datasheet factors.
TesT is the force data of the testing machine, which is resampled in postprocessing to match the sample frequency of the GSV4 (12.5 Hz and 125 Hz) or integrated electronics FLECS (100 Hz).
"Aligned" means the synchronization of strain gauge data and testing machine data.
For V2.2 (3p_3) there are data recorded with the GSV4 and with the integrated electronics FLECS.