Eigenfrequencies Invariance Properties in Deformable Flexion-Torsion Loaded Bodies -1- General Properties

Abstract

We present here, in the framework of resonnant behaviours, an eigenfrequency invariance properties for loaded flexural and torsional deformable bodies. We found that under a preload condition each eigenfrequency is invariant versus the load mN. For the mode 7 and beyond the preload conditions are less than mN = 1, and the seven first modes (form 0 to 6) can be easily modelled by polynomial functions of mN in the neighbourhood of useful mN. These properties open the way to new finite dimension controllers.