clc //Example 7.9 //Base_excitation //------------------------------------------------------------------------------ //Given data //Desired amplitude Y=0.5*(10^-3) //m //Desired frequency f=6 //Hz w=f*2*%pi //rad/s //mass of the table m=300/9.81 //kg res9=mopen(TMPDIR+'9_base_excitation.txt','wt') mfprintf(res9,'This is a forced, steady state vibration situation.\n\n') mfprintf(res9,'There are 2 supporting springs, hence net stiffness Ke=2k\n') mfprintf(res9,'Damping coefficient Ce = 0.05 Cc = 0.05*2*sqrt(Ke*m)') mfprintf(res9,'\n\nThe expression for desired amplitude Y is\n') mfprintf(res9,'\n\tY=Fo/sqrt((ke-m*w^2)^2+(Ce*w)^2)\n') mfprintf(res9,'Y will be maximum at resonance, i.e., w=wn\n') mfprintf(res9,'Thus the design condition is k=(1/2)m*w^2\n') k=0.5*m*(w^2) mfprintf(res9,'\tk=%0.2f kN/m\n',k* 10^-3) mfprintf(res9,'\nAt resonance, Y=Fo/c*w') Fo=(0.05*2*sqrt(2*k*m))*w*Y mfprintf(res9,'\nThe peak solenoid force required is %0.2f N',Fo) mclose(res9) editor(TMPDIR+'9_base_excitation.txt') //------------------------------------------------------------------------------ //-----------------------------End of program-----------------------------------