Evaluation of an angular accelerometer

The measurement of angular acceleration can be useful for modal analysis. The question is: "How well do these instruments work when exposed to linear as well as angular acceleration?" A free-free beam is used as the test structure and is driven by an electro-dynamic exciter in an open loop chirp, a closed loop random, and a closed loop swept sine test arrangement. The various test data are compared from test method to method as well as against a theoretical model with a surprising result The angular accelerometer is found to work very well over the range of frequencies tested.