LAUSR

The comparison of strain wave gear drives with four different geometries of the wave generator is presented. The commonly used elliptical geometry of the wave generator is compared with a simplified geometry based on two rolling elements, a geometry based on four rollers, and a newly proposed parabolic geometry for the wave generator. The comparison will be performed in terms of the average maximum stresses caused in the flexible spline due to the rotation of the wave generator. The finite element method and fully-parameterized automatically-generated two-dimensional finite element models are being used in this work. The flexible spline and the ring gear are considered deformable elements whereas the wave generator is considered as a rigid element in the finite element model. The results show that the best mechanical performance in terms of lower average values of maximum von Mises and tensile stresses is achieved with the simplified and parabolic wave generator geometries. Although yielding slightly higher maximum von Mises and tensile stresses, the elliptical wave generator provides the lowest average maximum absolute compressive stress. The worst mechanical performance was obtained with the four roller wave generator.