h a l f b a k e r yWe got your practicality ... right here.
add, search, annotate, link, view, overview, recent, by name, random
news, help, about, links, report a problem
browse anonymously,
or get an account
and write.
register,
|
|
|
Dare-Yo-Slow-Mo is a cross between a yo-yo and a bungy jump. It's called Dare-Yo-Slow-Mo because only the most daring will submit to its subtle terror.
The apparatus involved is quite simple, and consists of a large yo-yo, with a place for locating a person in the central part of the "spool'. Naturally
they are prevented from being flung out, as Dare-Yo-Slow-Mo descends and ascends on its relentless yo-yo journey.
A strong cable is wrapped many times around the inner spool containing the volunteer Dare-Yo-Slow-Mo participant. This cable terminates in a winding arm that allows the Dare-Yo-Slow-Mo to free-fall descend, but can also jerk it up and down to maintain the motion. A very tall platform acting as the launching pad completes the arrangement.
Now off you go! Try not to eat too much before your Dare-Yo-Slow-Mo session.
[link]
|
|
Is your body wedged along the axis of spin, or is it spread-eagled
across one of the disk faces? |
|
|
Spread out like an X. I was going to go for totally "loose" inside a cage, but I think that's too extreme, even for me. |
|
|
Someone needs to compute the max rate of spin at the bottom of the cable, and the G-forces experienced then. It might be too much for the body to tolerate. |
|
|
If the barrel is 1m in diameter, and is flung off a 20m
bridge, it would reach a speed in the region of 40mph
before reaching the 'apex'. If you assume no friction, and
have the barrel spinning at 18.6m/s (roughly 40mph) then
it must be spinning at 18.6/Pi = 5.9 revolutions per
second - which is approx 360 rpm. The G forces
experienced at the circumference at this point would be
around 144G - trained fighter pilots tend to black-out and
die around 9G. Suddenly reversing the direction of the
spin in the opposite direction at the bottom of the jump
should temporarily double these forces to 288G. |
|
|
A typical bungee jump is around 75m. |
|
|
Perhaps we should rebrand this as some form of cruel and
unusual capital punishment? |
|
|
Now you know why it's called a halfbaked idea. With a freely rotating centre, the person would stay in the same orientation, and only experience a type of slow motion bungee jump. |
|
|
The direction of spin does not reverse at the bottom. But the velocity of the device's centre of mass does reverse direction extremely suddenly, from +xmph to -xmph in the distance of the radius of the drum. |
|
|
And it's not freefall since gravity has to accelerate the device rotationally as well as vertically, as the cable unspools. |
|
|
//If the barrel is 1m in diameter, and is flung off a
20m bridge, it would reach a speed in the region of
40mph before reaching the 'apex'.// |
|
|
No. First of all, by "apex" you mean "nadir". |
|
|
But even so, your calculations are wrong because
they assume that the barrel has no angular
momentum. |
|
|
A barrel unwinding on a yo-yo rope will fall more
slowly than a barrel just dropped. In the same way, a
normal yo-yo does not descend at the same speed it
would if it were just dropped. |
|
|
Exactly. Some of the gravitational force is bled off to spinning a body with some initial rotational inertia. |
|
|
//subtle terror// nothing subtle about projectile vomiting. |
|
|
I actually don't think this would be that bad. In fact it could
be quite relaxing and not stomach churning at all. Drat! |
|
| |