Fall 2001 16.31 22–12 Weighting Matrix Selection ? A good rule of thumb when selecting the weighting matrices R xx (or R zz )and R uu is to normalize the signals: ? ? ? ? ? R xx = ? ? ? ? ? ? ? ? ? ? ? R uu = ? ? ? ? α 2 1 (x 1 ) 2 max α 2 2 (x 2 ) 2 max . . . α 2 n (x n ) 2 max β 2 1 (u 1 ) 2 max β 2 2 (u 2 ) 2 max . . . β 2 m (u m ) 2 max ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? The (x i ) max and (u i ) max represent the largest desired response/control input for that component of the state/actuator signal. ? The α i and β i are used to add an additional relative weighting on the various components of the state/control