the springs exert sufficient force in the z direction to move the plates, fully deploying the
mast. The force that fully deploys the mechanism is proportional to the cosine of the
angle (Figure 3-7).
Figure 3-5. Combination of struts and plates, a single side of a level
When stowed Fz = 6K((Lmax Lmin) +dmin) cos 0 max
=0 {Omax = 90} (3.1)
During deployment Fz = 6K ((Lmax Li) +dmin) cos 0 i (3.2)
Fully deployed Fz = 6K(dmin) cos 0 min (3.3)
As shown in Figure 3-6, Lmax, Li and Lmin are the lengths of the struts at various positions.
dmin is the difference between the free length of the spring and minimum length of the
strut (the amount that the spring is compressed when the strut is fully deployed) and
0max, Oi, and 0min are the angles of the strut at various positions