Measuring a Grid of Points on the Flank as State of the Art

To create a digital twin, it is state of the art to measure a grid of points on the flank, compare their measured coordinates to the coordinates calculated based on the gear macro and micro geometry, and feed the deviations back to the designed gear to convert it to a digital twin. This approach has been available for some time. The gear macro geometry, as designed in the gear design software, is exported as a Gleason GAMA software-compatible file or through GDE format, along with VDI/VDE 2610 guideline. Furthermore, direct export and import of a grid of points (rather than their coordinates and normal vector) from KISSsoft to GAMA is available. With this approach, the gear measurement machine knows the grid, the grid point designed coordinates and the grid point normal vectors. The measurement of the as-is coordinates of these points is then performed using a tactile probe. In Figure 7, the grid indicated consists of 8 × 8 points (green dots). The output is then an 8 × 8 table showing the deviation of the measured grid point coordinates from the designed grid point coordinates or rather the deviation as a scalar, to be understood in the direction of the normal vector of the corresponding point. This table is then imported into the design software, where the designed gear is modified by the imported deviation table to generate the digital twin. Such a digital twin is suitable for the assessment of tooth contact patterns and load distribution on the flank and will already be most helpful to assess manufacturing deviations like errors in pressure angle, helix angle, crowning or twist.