Vertical spring rate of the tires.
Computed by:
CONSUB
Input Variables Used:
■Compliance matrix
■Tire rates from ARRAY/9911
Method:
These values are taken from ARRAY/9911 or approximated in the CONSUB as described in earlier sections. If SVC must approximate the rates, it uses the compliance matrix entries to compute the simultaneous vertical forces required to move both front or rear wheel centers one unit vertically. This is done before the matrix is modified, so the vehicle body is free to move. Since the wheel centers are being moved the same distance, only the tires are flexing, and the forces computed are approximately the tire rates. The two simultaneous equations for one pair of front or rear tires are:
C( 3,3 ) Fl + C( 3,9 ) Fr = 1
C( 9,3 ) Fl + C( 9,9 ) Fr = 1
The determinate for this system is:
D = C( 3,3 ) C( 9,9 ) - C( 3,9 ) C( 9,3 )
Using Cramer's rule, the solution is:
Fl = [C( 9,9 ) - C( 3,9 )] / D
Fr = [C( 3,3 ) - C( 9,3 )] / D