An important part in coming up with new designs is studying previous attempts to do the same thing. In this case, the previous attempts have failed. Even so, studying where things have gone wrong can provide valuable insight.
Failed structure designed in previous attempt where (left) and (right) are parts of the same structure
Principle of operation:
When the pushing pad is pushed down with
a micro-probe, this would lift the mirror up. The torsion hinge would allow the
mirror to move up while at the same time being attached to the silicon layer.
Then when the mirror is in the upright position, the two pulling bars would be
pulled by using the pulling rings. This ensures that the locking mechanism latch
thus making sure that the mirrors would stand vertically. There are a total of
three operations needed, one push and two pulls. Suspensions are present to make
sure that the whole pulling bar remains in the surface plane, so that the
locking mechanism will be in the same plane as the pulling bar.
The mechanism for latching the mirror in place is faulty. Looking at the figures above, one could see that the dimensions for the locks are incorrect. The suspension springs broke resulting in important structures floating away during fabrication. Several critical features that are supposed to be in the same plane are misaligned as was shown in the figures.