cantzero.m

vibration simulation using ansys and matlab 一书中的程序

	echo off
%	cantzero.m 		plots ANSYS frequency response results and overlays
%	constrained system poles, which are the same as the unconstrained
%	system zeros.  Uses eigenvalues and eigenvectors from cantfem.inp
%	and cantzero.inp to plot overlay of zeros of cantilever with poles 
%	of tip supported cantilever, showing the correspondence.  Calls 
%	cantzero_freq.m, cantfem_magphs.m.  Loads information from 
%	cantfem_magphs.m and cantzero_freq.m.

   	clear all;
	
	clf;

	cantfem_magphs;			%  load frequency and magnitude results from cantfem.inp

	freq = freqmag(:,1);
	
	mag = freqmag(:,2);
	
	cantzero_freq;			%  load frequency results from cantzero.inp, cantzerofreq

	magdb = 20*log10(mag);
	
	semilogx(freq,magdb)
			
	magplot = -130*ones(size(cantzerofreq));

%	plot magnitude versus frequency from ANSYS and overlay 'o' for the resonant
%	frequencies of the constrained beam

	semilogx(freq,magdb,'k-',cantzerofreq,magplot,'ko')
	title('Cantilever Driving Point Transfer Function and Constrained Pole Frequencies')
	xlabel('frequency, hz')
	ylabel('magnitude, db')
	legend('unconstrained system','constrained system poles','match unconstrained system','zeros')
	grid on