Effect of Cam Insertion on Stresses in Harmonic Drive in Industrial Robotic Joints

Stress and strain analysis on flex gear cup of strain wave gearing or harmonic drive due to insertion of conventional cam SWG and split cam SWG is studied without assembling the ring gear. Harmonic Drive is supposed to perform kinematically better with proposed split cam than the conventional cam. However, the stress pattern on the FG changes when HD is assembled with Split cam. The comparison study is carried out using finite element method and experiments. The overall stresses on FG cup with split cam are more and it can be seen with finite element analysis. However, the nodal results show that the strains around the tooth contact between FG teeth and RG teeth is less with split cam. These results are further supported with experiments. The experimental results have good agreement with the FEA results.