Mechanical engineering advice

Maby look into a design similar to what a seatbelt in a car uses. Almost a velocity driven ratchet.

i'd be curious to see how you would address the problem of someone falling...say just before the 3rd clip, where it's high enough to get hurt but do you have enough time to engage a brake system to not deck? the margin of play is very small in instances like this, no?

How about an autobelay that takes the energy generated during descent and feeds that back into the grid to reduce the electrical bill? =P