oz 314 to adjust up or down depending on g the strut cross sectional area is s the linear displacement of the strut is y and it is given by equation 2 mentioned above the volume v y of the strut is given by the following equation the pressure p y on the strut is related to the force f y acting on the strut p y v y f y s s h u2212 y f y h u2212 y p 0 v 0 f y f 0 h h u2212 y eq 8 r 1 y f y u2212 f 0 f 0 h h u2212 y u2212 f 0 f 0 y h u2212 y r 1 y f 0 y h u2212 y eq 9 r 2 y u2212 r 1 u2212 y u2212 f 0 u2212 y h y r 2 y f 0 y h y eq 10 going back to the torque equation 3 and replacing g l r 1 and r 2 in terms of the strut linear displacement y the following calculations hold m g l h u2212 r 1 l r 2 l m g h l y g 2 l 2 h y h 2 y 2 because the system sway is limited to small angular displacements one can use the following.