Re: Need speed switch for DIY funicular/hillside elevator

["Jon Woellhaf" <jonwoellhaf@xxxxxxxxxxx>]

<astutesolutions@xxxxxxxxxxxxx> wrote in message
news:1162403122.431605.268350@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
> No, that would be the speed at which I would assume its a runaway.  If
> you mean by terminal velocity the maximum speed it would reach on a
> runaway condition, I don't have a clue.

Yes, I mean the maximum speed during a runaway condition -- like if both
cables failed.

I believe you said the vertical distance is 70 feet. That means the maximum
speed the cart could reach is 46 mph, discounting rolling friction and air
resistance -- if I remember my freshman physics correctly. Accounting for
rolling friction and air resistance, I estimate the terminal speed would be
no more than 40 mph.

That's probably too fast for my initial idea of a passive emergency
deceleration system to work. I was thinking of a net across the bottom of
the track held by bungee cords attached to posts or trees.

I think an engineer could design a water filled coaxial tube shock absorber
that would safely decelerate a runaway cart. You'd have to add track beyond
the normal lower platform. It looks like there's room.

A simpler solution is to add track all the way to the water with a level or
slightly inclined runout portion and just let the runaway cart and occupants
get launched into the lake. <g>

Really cool device, by the way.

Jon