Using a discrete time sampling introduces errors into damping measurements. These are systematic errors that cannot be reduced by averaging, and they are particularly significant for light damping. Using an exact damping measurement method for lightly and non-lightly damped systems and for viscous and hysteretic damping, these errors are studied allowing the errors to be specified in terms of confidence limits. This allows i) the measurement system parameters and measurement errors to be related, and ii) the confidence limits of the actual value of system damping to be calculated given the measured value and the normalized frequency resolution.

The author performed this work while on an invited stay at the named institution, and he acknowledeges support by a research grant from the Spanish Ministerio de Ciencia e Innovación (BIA2009-11753) to present this work at Internoise 2010

39th International Congress on Noise Control Engineering 2010 (INTER-NOISE 2010), 13-16 June 2010, Lisbon, Portugal. 9 páginas, 4 figuras, 3 tablas