Forums > Beginner Poi Moves > The mathematics of a Figure8

Login/Join to Participate
Page:
Analemmaenthusiast
384 posts
Location: West LA


Posted:
There are threads about the mathematics of weaves and so on - but try to figure out what is behind this basic little move which forms (next to the circle) the fundamentals of Poi. Its not only the change of sides. Where is the pull (is there a pull?!?), what happens if you play extended/isolated Figure8, what different ways are there to play it, what happens with different Crossover Points . . . .

Ill leave the mathematical aspects to NYC and the aesthetical ones to your imagination smile


ubbloco

To learn - read. To know - write. To master - teach . . .


Jomember
517 posts
Location: Sheffield, England


Posted:
It feels purple.



Jo. smile



PS. I would mathmatically expand on 'purple' if it wasn't gone midnight confused
EDITED_BY: Jo (1110155193)

Educate yourself in the Hazards of Fire Breathing STAY SAFE!


Analemmaenthusiast
384 posts
Location: West LA


Posted:
You got problems . . . . its 4:24 Afternoon biggrin

To learn - read. To know - write. To master - teach . . .


GlåssDIAMOND Member
The Ministry of Manipulation
2,523 posts
Location: Bristol, United Kingdom


Posted:
Yes smile
But not to spend the time to type
and not to post here smile

NYCNYC
9,232 posts
Location: NYC, NY, USA


Posted:
You're just doing a circle in the x/z plane. Well two really.

Then moving your hand side to side in the Y plane at half the frequency that you're doing circles.

Don't have my graphing calculator with me but that's the idea of it.

Well, shall we go?
Yes, let's go.
[They do not move.]


TheWibblerGOLD Member
old hand
920 posts
Location: New Zealand


Posted:
if the circle is in the x-z plane and theta is the angle, lets say

x is proportional to sin(theta)

z is proportional to cos(theta)

is y proportional to tan(theta)???? atan(theta) perhaps???

The amplitude is equal to the distance from the poi head to the center of rotation, this is what changes with giant / isolation.

This set up is the same where ever you do the pattern, however your body's relation to it changes and that's why you need to practice it in differnt positions.

When the pattern is horizontal gravity acts in a different direction but this can be countered be your movements.

m

Spherculism ~:~ The Act of becoming Spherculish.


StoneGOLD Member
Stream Entrant
2,829 posts
Location: Melbourne, Australia


Posted:
hi poiboxII,



I agree, the fundamentals of poi are infinite and the secret is the figure 8.



Give me the beauty of the lemniscate over Pi any time.



cheers wink

If we as members of the human race practice meditation, we can transcend our fear, despair, and forgetfulness. Meditation is not an escape. It is the courage to look at reality with mindfulness and concentration. Thich Nhat Hanh


Elemental666GOLD Member
member
45 posts
Location: Bville, OK, USA


Posted:
I started spinning with photons on short ballchains doing what they call a corckscrew here. I taught my best friend how ot get started by cuffing him and telling him to make a figure 8. Later he got into POI and showed me how to do a 3bt weave by cuffing me and telling me to make an infinity...

its all prespective

and the pi theta oh gamma [censored] make my head hurt...

TheWibblerGOLD Member
old hand
920 posts
Location: New Zealand


Posted:
Hey stone, thanks for that link, lemniscates are certainly very beautiful and that site is awesome thank you thank you. *runs off to geek out*

Spherculism ~:~ The Act of becoming Spherculish.


Analemmaenthusiast
384 posts
Location: West LA


Posted:
Written by:

You're just doing a circle in the x/z plane. Well two really.

Then moving your hand side to side in the Y plane at half the frequency that you're doing circles.



You wish wink

Written by:

is y proportional to tan(theta)???? atan(theta) perhaps???



I would say . . . . probably confused But ask NYC to be shure since my PhD in Mathematics is still on Kao Sarn . . . biggrin

A Figure8 always involves a planechange given by an impulse of the hand. To describe it properly you have to analyse 2 points (Poihead and Hand) - which makes it more difficult. Every Figure8 is an isolation or extension (small but still)!

A different setup which shows how complex this "basic" can get: Change the Poi back and forth between different planes but around the same center of rotation (Tilting planes) - Which mathematics apply, what influence have different Crossover Points, is this still a figure8, what happens if you push the angle between the planes further than 90degree . . . ?
Hmmmmmm . .. . Poilosophy ubblove

andy

To learn - read. To know - write. To master - teach . . .


NYCNYC
9,232 posts
Location: NYC, NY, USA


Posted:
X=cos.5T
Y=sinT

How hard is that? Now get Z to make circles. Or did your PhD not cover 9th grade math? eek wink

Well, shall we go?
Yes, let's go.
[They do not move.]


StoutBRONZE Member
Pooh-Bah
1,872 posts
Location: Canada


Posted:
A little beyond grade nine math I think.

We have a poi head moving in three dimensional space. basically a bent figure 8 with a moving point of rotation. This could get really complicated,,,how mush information were you looking for ? I suggest a visit to the university mathematics department

KaelGotRiceGOLD Member
Basu gasu bakuhatsu - because sometimes buses explode
1,584 posts
Location: Angels Landing, USA


Posted:
Is this all truly necessary? wink

heh

To do: More Firedrums 08 video?

Wildfire/US East coast fire footage

LA/EDC glow/fire footage

Fresno fire


Psycho_lemmingSILVER Member
Running hippy spinning lemming
15 posts
Location: Scotland


Posted:
42

Fear leads to anger; anger leads to hate; hate leads to suffering...


Analemmaenthusiast
384 posts
Location: West LA


Posted:
meditate

weavesmiley

Does spinning really look like this smiley?

biggrin

meditate

andy

To learn - read. To know - write. To master - teach . . .


StoneGOLD Member
Stream Entrant
2,829 posts
Location: Melbourne, Australia


Posted:
Hi Spherculism, I stumbled on that maths site looking for symbols like the Ouroboros (snake biting it’s own tail). Then there are Cassinian Ovals which are way beyond me.



While I’m not a maths person, I love the symmetry of the OO, and my appreciation of the esoteric Pi is growing. So I can really only add some of my thoughts on the basics like - Where is the pull (is there a pull?!?)



OOPS, edit need to revise this bit, will post later smile
EDITED_BY: Stone (1110882196)

If we as members of the human race practice meditation, we can transcend our fear, despair, and forgetfulness. Meditation is not an escape. It is the courage to look at reality with mindfulness and concentration. Thich Nhat Hanh


StoutBRONZE Member
Pooh-Bah
1,872 posts
Location: Canada


Posted:
So no mathematical equation for the figure eight yet????

You can actually spin something like those Cassinian Ovals in a figure traced on the ground way..if you do the reverse weave, there's your figure eight,,,do a hand wrap, and grab the poi then slowly unwind them in the horizontal plane with your arms extended. When the poi are fully unwound from your hands. spin your body around with the poi straight out.......viola,,,Cassinian Ovals,,,from an ant's perspective.

That's one on the challenging aspects of poi, the fact that the toys aren't rigid,,,making plane changes a little more demanding than with a staff. If your planes go a little out of control with a staff it's usually just a matter of a small hand tweak to correct it,,,but with poi sometimes I find I have to abandon what I was just starting to do and bail out into something where I can more easily regain control,,,,,,like a low turn or separated butterfly.

NYCNYC
9,232 posts
Location: NYC, NY, USA


Posted:
Written by: stout


So no mathematical equation for the figure eight yet????





I gave you the formula!

It's right!

Well, shall we go?
Yes, let's go.
[They do not move.]


GlåssDIAMOND Member
The Ministry of Manipulation
2,523 posts
Location: Bristol, United Kingdom


Posted:
Its an approximation wink

Depends on your tolerance/ required accuracy as to whether you consider it "right".

Its simple (like me smile ) which is good, for most situations.

But for some of the ways that I've been looking at things

I don't dig some of the assumptions implicit in that solution.
EDITED_BY: Glåss (1111141754)

Analemmaenthusiast
384 posts
Location: West LA


Posted:
Written by:

It's right!



Then I have never seen someone spin a figure8
Probably we should take a look at the circle first. Which is the physical force equation for a mass circling constantly in a gravity field? The figure8 is more complicated than it seems.

Written by:

But for some of the ways that I've been looking at things
I don't dig some of the assumptions implicit in that solution




This is proper English biggrin (Brits....)

andy

To learn - read. To know - write. To master - teach . . .


NYCNYC
9,232 posts
Location: NYC, NY, USA


Posted:
Wait wait wait wait wait wait wait...

Are you looking for an equation to define the path of the poi going through a figure 8? If so, that's easy.

If you're looking for each FORCE necessary to make the poi spin in a figure 8, that's hard.

I'll try and come up with a proper 3D graph to shut Glass up. wink

Well, shall we go?
Yes, let's go.
[They do not move.]


colemanSILVER Member
big and good and broken
7,330 posts
Location: lunn dunn, yoo kay, United Kingdom


Posted:
i think what andy is saying is, "who spins a perfect circle?".

the answer to which is obviously, "no-one".

so the next question is, "what is the precise equation of the path of a poi, taking into account the necessity of applying a force near to the centre of rotation at some point in the cycle? where and how much does the application of this force (and the others applying to the poi head and your hand) cause the path of the poi to deviate from a circular one?"

the answer to which is...?


cole. x

"i see you at 'dis cafe.
i come to 'dis cafe quite a lot myself.
they do porridge."
- tim westwood


GlåssDIAMOND Member
The Ministry of Manipulation
2,523 posts
Location: Bristol, United Kingdom


Posted:
What Cole and Andy said smile
NYC
Actual Poi Path = f(speed + and many other factors)

NYCNYC
9,232 posts
Location: NYC, NY, USA


Posted:
Well DUH!

I'm talking about a theoretical equation.

Jerks. wink

If you want to get as technical as you guys are:
There is no poi.

So no, I have not resolved all of the string theory dynamics to govern each subatomic particle within the poi.

But the path ROUGHLY follows the equation above.

Next thing you guys will be asking for your money back on the Circles of Light videos because they're not actually perfectly circular due to the gravitational influence of the earth, sun, moon and Coleman's mother.

My equation works if you assume the poi are spun in circles.

Otherwise, I'd better see some Heisenburg uncertainty in the radius of the poi string.

Jerks.

wink

Well, shall we go?
Yes, let's go.
[They do not move.]


ado-pGOLD Member
Pirate Ninja
3,882 posts
Location: Galway/Ireland


Posted:
i agree with jo

Love is the law.


Dr_MollyPooh-Bah
2,354 posts
Location: Away from home


Posted:
Written by: coleman


"who spins a perfect circle?".





madmen
smile

TheWibblerGOLD Member
old hand
920 posts
Location: New Zealand


Posted:
Well if you're gonna get technical about the path of the poi then don't forget to factor in the rotation of the earth, movement around the sun, galaxy rotation and so on ubblol A circle therefore becomes a crazy complicated spiral with lots of unknowns.

You can't spin a circle because perfect circles don't exist in nature, sphercles might tho smile

NYC, i never understand why you give 2D solutions to 3D problems ~ or am i missing something? Still love 'em tho smile

m

Spherculism ~:~ The Act of becoming Spherculish.


colemanSILVER Member
big and good and broken
7,330 posts
Location: lunn dunn, yoo kay, United Kingdom


Posted:
Written by: spherculist


Well if you're gonna get technical about the path of the poi then don't forget to factor in the rotation of the earth, movement around the sun, galaxy rotation and so on ubblol A circle therefore becomes a crazy complicated spiral with lots of unknowns.





ubblol

i think the idea is to get an equation that produces the same trails (paths) as a poi spun by a human would.
the

Written by: spherculist


You can't spin a circle because perfect circles don't exist in nature, sphercles might tho smile





what's the equation of a sphercle? wink

Written by: spherculist


NYC, i never understand why you give 2D solutions to 3D problems ~ or am i missing something? Still love 'em tho smile

m




its because of the circle assumption - the path is set to that of a circle in one axis so assuming that is known, the two equations nyc descirbes apply to the other two axis smile


cole. x

"i see you at 'dis cafe.
i come to 'dis cafe quite a lot myself.
they do porridge."
- tim westwood


StoutBRONZE Member
Pooh-Bah
1,872 posts
Location: Canada


Posted:
Maybe Andy should clarify what he had in mind when he first posted this thread, I was thinking it was an equation to describe the figure 8 pattern one poi makes when spun in a simple back and forth motion across your body.

String theory does not apply here, and we can assume a perfect circle, for the sake of the math. Heisenberg only applies to poi spinning when you're doing a live show,,,think about it.

You can actually make the figure 8 shape we're talking about from a loop of wire.

Factoring gravity and the forces required to counteract it makes the equation a lot more complicated as does factoring on the back and forth motion of your hand ( as opposed to one theoretical point of rotation, like holding your hand rigid straight out in front of you when spinning this pattern)

Start with the basic "framework" then build from there.

Doesn't a drop of water falling from a leaf, into a flat pond create perfect circles of ripples?

colemanSILVER Member
big and good and broken
7,330 posts
Location: lunn dunn, yoo kay, United Kingdom


Posted:
stout - that's what nyc was saying.

the equations nyc gives are for circular poi motion in one axis.

we want equations for real poi motion in that axis.

if you get an equation that factors the hand movement in and resolve the forces you will (as a necessity) have to factor gravity or at the very least friction (air resistance) to balance out those forces.

which as you say, makes it very complicated.

however, the advantage is that with an equation for the motion of the hand, we should then be able to specify the range of trails possible for spinning normally (hand adds force to the poi from the same side of the center of rotation) and for isolated spinning (hand powers poi from opposite side of point of rotation).

i don't even want to try.


cole. x

"i see you at 'dis cafe.
i come to 'dis cafe quite a lot myself.
they do porridge."
- tim westwood


GlåssDIAMOND Member
The Ministry of Manipulation
2,523 posts
Location: Bristol, United Kingdom


Posted:
Stout... good post.

NYC - additionally, I don't agreet with the assuptions you make which define the shape out of plane
(ie when viewed from above.)

I used to view isolation as being like spinning the other solution of a quadratic equation, you know the negative one that you always threw away because it was impossible to have a peice of string with a negative length.

Page:

Similar Topics

Using the keywords [mathematic * figure8] we found the following existing topics.

  1. Forums > The mathematics of a Figure8 [43 replies]

      Show more..

HOP Newsletter

Sign up to get the latest on sales, new releases and more...