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Forums > Beginner Poi Moves > The mathematics of a Figure8

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Analemma


Analemma

enthusiast
Location: West LA

Total posts: 384
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 . . .

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Jo


Jo

member
Location: Sheffield, England

Total posts: 517
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!

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Analemma


Analemma

enthusiast
Location: West LA

Total posts: 384
Posted:You got problems . . . . its 4:24 Afternoon biggrin

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

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Glåss
DIAMOND Member since Nov 2001

Glåss

The Ministry of Manipulation
Location: Bristol

Total posts: 2523
Posted:Yes smile
But not to spend the time to type
and not to post here smile


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NYC


NYC

NYC
Location: NYC, NY, USA

Total posts: 9232
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.
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TheWibbler
GOLD Member since Apr 2003

old hand
Location: New Zealand

Total posts: 920
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.

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Stone
GOLD Member since Jun 2001

Stream Entrant
Location: Melbourne

Total posts: 2830
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

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Elemental666
GOLD Member since Feb 2005

member
Location: Bville, OK

Total posts: 45
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...


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TheWibbler
GOLD Member since Apr 2003

old hand
Location: New Zealand

Total posts: 920
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.

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Analemma


Analemma

enthusiast
Location: West LA

Total posts: 384
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 . . .

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NYC


NYC

NYC
Location: NYC, NY, USA

Total posts: 9232
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?
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Stout
SILVER Member since May 2004

Stout

Pooh-Bah
Location: Canada

Total posts: 1872
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


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KaelGotRice
GOLD Member since Jul 2003

KaelGotRice

Basu gasu bakuhatsu - because sometimes buses explode
Location: Angel's Landing, USA

Total posts: 1584
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

<img src="/ubbthreads/images/graemlins/ubbrollsmile.gif" alt="" />

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Psycho_lemming
SILVER Member since Jul 2004

Psycho_lemming

Running hippy spinning lemming
Location: Scotland

Total posts: 15
Posted:42

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

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Analemma


Analemma

enthusiast
Location: West LA

Total posts: 384
Posted:meditate

weavesmiley

Does spinning really look like this smiley?

biggrin

meditate

andy


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

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Stone
GOLD Member since Jun 2001

Stream Entrant
Location: Melbourne

Total posts: 2830
Posted:Hi Spherculism, I stumbled on that maths site looking for symbols like the Ouroboros (snake biting its own tail). Then there are Cassinian Ovals which are way beyond me.



While Im 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

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Stout
SILVER Member since May 2004

Stout

Pooh-Bah
Location: Canada

Total posts: 1872
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.


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NYC


NYC

NYC
Location: NYC, NY, USA

Total posts: 9232
Posted:Written by: stout

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




I gave you the formula!

It's right!


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Yes, let's go.
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Glåss
DIAMOND Member since Nov 2001

Glåss

The Ministry of Manipulation
Location: Bristol

Total posts: 2523
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: Glss (1111141754)


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Analemma


Analemma

enthusiast
Location: West LA

Total posts: 384
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 . . .

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NYC


NYC

NYC
Location: NYC, NY, USA

Total posts: 9232
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.
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coleman
SILVER Member since Aug 2002

coleman

big and good and broken
Location: lunn dunn, yoo kay

Total posts: 7330
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

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Glåss
DIAMOND Member since Nov 2001

Glåss

The Ministry of Manipulation
Location: Bristol

Total posts: 2523
Posted:What Cole and Andy said smile
NYC
Actual Poi Path = f(speed + and many other factors)


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NYC


NYC

NYC
Location: NYC, NY, USA

Total posts: 9232
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.
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ado-p
GOLD Member since May 2004

ado-p

Pirate Ninja
Location: Galway/Ireland

Total posts: 3882
Posted:i agree with jo

Love is the law.

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Dr_Molly


Dr_Molly

Pooh-Bah
Location: Away from home

Total posts: 2354
Posted:Written by: coleman

"who spins a perfect circle?".




madmen
smile


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TheWibbler
GOLD Member since Apr 2003

old hand
Location: New Zealand

Total posts: 920
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.

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coleman
SILVER Member since Aug 2002

coleman

big and good and broken
Location: lunn dunn, yoo kay

Total posts: 7330
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

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Stout
SILVER Member since May 2004

Stout

Pooh-Bah
Location: Canada

Total posts: 1872
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?


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coleman
SILVER Member since Aug 2002

coleman

big and good and broken
Location: lunn dunn, yoo kay

Total posts: 7330
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

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Glåss
DIAMOND Member since Nov 2001

Glåss

The Ministry of Manipulation
Location: Bristol

Total posts: 2523
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.


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