"A60,B60,C60 are the discrete-time matrices of the servomechanism dynamics model (1) sampled at 60 KHz, in other words, A 60 = ??? AT 60 , B 60 = ??? 0 T 60 ??? A ( T 60 - ?? ) B ??? ?? C 60 = C G60 is a matrix chosen so that the eigenvalues of A60+G60C60 have a magnitude less than one and close to zero." . . . .