Digital tooth contact analysis of face gear drives with an accurate measurement model of face gear tooth surface inspected by CMMs

The digital tooth contact analysis (DTCA) of machined gears is an effective way to evaluate both the design and manufacturing before rolling tests. This is very challenging to face gear drives due to two aspects. (1) No measurement standard is available for face gears to obtain an accurate measurement model. (2) The DTCA equation is highly nonlinear related to the complex geometry of face gears. To fulfil those problems, this work presents an accurate measurement model of the face gear tooth surface, wherein the DTCA is implemented with a robust algorithm. An effective measurement strategy based on sensitivity analysis is proposed to establish a measurement coordinate system (MCS), and the relationship between the MCS and the design coordinate system (DCS) is further analyzed to compensate the measurement errors. Subsequently, the B-spline fitting technology is applied to reconstruct the measurement model. Furthermore, the equation of meshing is simplified to reduce its nonlinearity and realize the DTCA. The proposed method is verified by both the finite element analysis (FEA) and a rolling test.