Analysis on the mechanical performance of an externally excited harmonic drive

This paper presents a design method for a harmonic drive (HD) with the full conjugate tooth profiles and dual-eccentric circular-arcs (DECA) external wave generator (WG). First, the conjugate combined cycloid tooth profile (CCTP) equations for the circular spline (CS) and flexspline (FS) is established to analyze the meshing characteristics of the tooth profiles, such as the line of action and meshing angle, etc. Then a multi-tooth contact model considering assembly preload force and internal component interaction is established to systematically study the influence of the parameters on the bearing characteristics and friction losses of the whole machine. Finally, the finite element model of the whole machine is developed to verify the effectiveness of the theoretical model. The simulation results show that the distribution of assembly deformation force and load contact force of FS is basically consistent with the theoretical model, and the radial resultant force on WG during the assembly agrees with the theoretical value to within 2.3%. The research outcomes provide a new way to study high bearing and impact resistant HD.