This Data Item implements a Fortran computer program for the
\nparameter estimation of linear systems from frequency response
\nmeasurements. The method is primarily based on the procedure
\ndescribed in ESDU 90006 but has been modified to account for the
\neffects of residual modes of response, i.e<\/i>. gain and phase
\nvariations of modes whose effects lie predominantly outside the
\nrange of frequencies of the analysis data but which nevertheless
\nhave an influence within the range of analysis.<\/p>\n
The system is assumed modelled as a set of lightly-damped
\ncoupled second-order differential equations with constant
\ncoefficients and the response determined from solution of these
\nequations is equivalent to the sum of the responses of a related
\nset of single degree-of-freedom systems. It is also assumed that a
\nset of frequency response measurements is available from forced
\nharmonic excitations of the system and that these measurements
\nencompass the major response activity of the modes to be
\nidentified. The method has been implemented as an automatic
\ncomputer-based procedure, but relies on a visual inspection of a
\nNyquist plot of the measurement data to provide initial estimates
\nof the resonant frequency of each mode of response together with
\nthe frequency bands of data associated with each mode. The computer
\nprogram has been written to deal with a single-input single-output
\nsystem where displacement measurements obtained at different
\npositions in the system are treated separately.<\/p>\n
The program evaluates initial estimates of the natural frequency
\nand damping ratio of each mode together with the coefficients of
\nthe complex forcing functions and residual terms. These values
\nprovide a starting point for a nonlinear parameter estimation
\nprocedure using a Newton-Gauss algorithm. Examples illustrate the
\nuse of the computer program to estimate the parameters of systems
\ncontaining both two and four degrees-of-freedom.<\/p>\n","protected":false},"excerpt":{"rendered":"
Parameter Estimation of Linear Systems from Frequency Response Measurements (Computer Program)<\/b><\/p>\n\n\n
\n Published By<\/td>\n Publication Date<\/td>\n Number of Pages<\/td>\n<\/tr>\n \n ESDU<\/b><\/a><\/td>\n 2010-06<\/td>\n NA<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n","protected":false},"featured_media":0,"template":"","meta":{"rank_math_lock_modified_date":false,"ep_exclude_from_search":false},"product_cat":[2675],"product_tag":[],"class_list":{"0":"post-559173","1":"product","2":"type-product","3":"status-publish","5":"product_cat-esdu","7":"first","8":"instock","9":"sold-individually","10":"shipping-taxable","11":"purchasable","12":"product-type-simple"},"_links":{"self":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product\/559173","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/types\/product"}],"wp:attachment":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/media?parent=559173"}],"wp:term":[{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product_cat?post=559173"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product_tag?post=559173"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}