Page 63 - Thomson, William Tyrrell-Theory of Vibration with Applications-Taylor _ Francis (2010)
P. 63

50                                             Free Vibration   Chap. 2

                             2-59  The  equation  of motion  for  the  system  of Fig.  P2-59  with  Coulomb  damping  can  be
                                 written  as
                                                        mx   kx = ¡iF sgn ( i)
                                 where  sg n (i)=   ±1  (i.e.,  sgn(i) =  +1  when  x  is  negative  and  -1   when  i   is
                                 positive). The general solution to this equation is
                                                     x(t)  = A sin   + B cos (o^t
                                                             iiF    .
                                                           -h -p  sgn(.r)
                                 Evaluate  the  constants  A  and  B  if  the  motion  is  started  with  the  initial  conditions
                                 jc(0) = Xqand  i(0)  =  0.

                                           k
                                   I     ->VWV-
                                                                     Figure P2-59.
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