Rotational Compliance Measurements of a Flexible Plane Structure Using an Attached Beam-like Tip, Part 1: Analysis and Numerical Simulation

The present paper describes a simple, indirect technique for measuring the rotational compliance of an attached thin-walled plane structure. The technique, called “Tip Excitation Technique (TET),” uses an L-shaped beam tip fixed at one point of the original structure where the rotational compliance is to be evaluated. The tip acts as a mechanical converter transforming an exciting force applied at the tip into an excitation moment applied to the original structure and reciprocally, to convert a rotational response into a translational one. The rotational compliance is evaluated using simple analytical relations that partially eliminate the effect of tip inertia on the structure. Finite element simulations show that the technique can he applied to the study of a typical plate over a frequency range involving relatively strong modal behavior. The low sensitivity of the technique to variations of different physical factors of the tip-plate configuration demonstrates its potential for experimental purposes.