[TowerTalk] Regarding Worm Gear Drive Winches

[jimlux]

Richard (Rick) Karlquist wrote:
> 
> 
> 
> 
> What I wish someone would make is a conventional gear winch
> with a brake that worked on air resistance.  A gear train
> would make a paddle on an axle rotate at high speed such that
> the winch would free run downward at a controlled rate without
> anything overheating.  Schwinn make an exercise bike that worked
> on this principle.  It eliminated the troublesome resistance
> pads.  We now return you to your regular winch.

This is a pretty standard thing they use in the special effects industry 
to regulate the rate at which someone falls. But it takes a bigger air 
paddle than you think.. Water might actually be a better drag medium.

The challenge is actually not in the drag (an electric generator would 
also work) but in reducing the gear train losses.  For the falling 
person speed regulator, they feed off a fairly large diameter drum, to 
keep the rotation rate reasonable.