Modal analysis in relation to the casing of an electric power steering system

The article presents the results of modal analysis (experimental and numerical using Finite Element Method - FEM) with reference to the power steering worm drive gear housing. The experimental analysis was performed by the Least Squares Complex Exponential (LSCE) method using a modal hammer equipped with a force sensor which allowed the measurement and recording of the excitation. Numerical analysis was based on the Finite Element Method in PLM Siemens NX 10. Based on results from the experimental modal analysis the FEM numerical model was tuned. The resulting consistency of results led to the conclusion the correctness of the model FEM. The adapted numerical model was used for further analysis with respect to modified power steering worm drive gear housing designs. The obtained results allowed to estimate how the change of the material and adjusting the geometrical form to the strength conditions will affect the frequency and form of the vibration of the modified worm drive gear housing.