MECHANICAL IMPEDANCE AND MOBILITY CONCEPTS.
Abstract
The purpose of the report is to discuss fundamental concepts involved in mechanical impedance and mobility. The equations used in the formulation of the concepts are examined as to meaning and content. It is demonstrated for any prescribed structure that every possible observed mobility element is independent of the number and location of the other measurement points and that every possible observed mechanical impedance element is not. The effects upon the mobility and impedance arrays are examined for simple expansions and contractions of the tensor. Since mobility is not affected by changes in the number of observation points, remeasurement is not required at the observation points that are retained during expansion or contraction of the tensor; but since any changes in the observation points for impedance measurements requires changes in the blocking forces, the observation points that are retained are affected. An undamped lumped parameter system (a three-mass system on a rigid base and constrained to unidirectional motion) serves to illustrate the effects on the tensor elements of impedance or of mobility of the choice of the number and location of measurement points. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 29, 1966
- Accession Number
- AD0638206
Entities
People
- G. J. O'hara
Organizations
- United States Naval Research Laboratory