8KHIOo,0m 1 aKHOOOIm H g000pm eqns 4.76,4.77
aMgHIOum HHIOOOm 'HI0OOOpm HlOOOpm
The vertical stiffness is similarly found by applying the maximum force (Mgviooopm) that
would cause the maximum measurable vertical displacement (8viooopm).
eqn 4.78
Klooon =Knooo
80vai OOO pm
The variance in the Kv expression can be found using eqn 4.78.
u \ ,U2/( 0M 8KvIOOOpm +. 2 ,0p ,Kvnoo0o"
"c ( ooo,)=uM g (( Mguooo, ).OM + u (, vooo ( a8 ---.
The evaluated partial derivatives in eqn 4.79 are expressed in eqns 4.80 and 4.81.
8Kvlooopm 1 K vioO P MgVooo000 eqns 4
M 0VOOOPm 8VlOOOpm V000vooopm V21000pm
eqn 4.79
.80,4.81
4.3.6 Stiffness Expansion
4.3.6.1. (Mg): Calibration force
The value for the calibration force used in eqns 4.74-4.81 is the force that would
cause a 1000pm displacement based on the stiffness of the flexure. The uncertainty in
this force value u(MgH,V) is taken as 1 tN which is the resolution of a laboratory grade
scale.
4.3.6.2 (5): Calibration displacement
The uncertainty in delta is determined from the displacement-voltage calibration
constant and the sensor voltage at a 1000 im displacement.
SmIOopm CHV ooop. eqn 4.82