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Balance defined - Page 3  

post #61 of 83

Somebody hand me a can opener

Quote:
Originally Posted by BigE View Post
Sorry.

I'm guessing "balance vector" is the problem.

The balance vector is the result of adding together all the forces acting on the skier. The centrifugal force in a turn acts to pull the skier out of the turn. Gravity to pull them down. Snow friction to push the skiis back. Air / wind resistance to push on the body. When you add all of these together, you get a net force, acting on the center of mass (CM), pulling the CM in a particular direction.

You can draw this force as an arrow, with a tail at the CM and head pointing directly in the direction this net force is pulling.

The Base of Support is the entire area between all points touching the snow that support the skier.

If you orient the base of support so that this balance vector is pointing into it you will stay upright. It does not matter where in the base of support the net force is pulling the CM (ie, the balance vector points). It matters only that this balance vector is pointing somewhere into the base of support.

You can look at all the force as vectors, and add them up, by putting the tail of one to the head of another, like a chain.

This might help: -- the money shot --


which is http://www.ronlemaster.com/images/20...ce-width-A.jpg

The green arrow is the resultant of the yellow and blue arrows; it is the balance vector. For simplicity, it ignores snow friction and air resistance. It points into the base of support -- directly to the inside edge of the outside ski.

That shows Herman's weight to be over a very dominant outside ski.

If the green arrow went between the legs, the balance point would be between the feet, and you'd see both skis decambering. In this photo, it looks like weight is just starting to be applied on the inside ski, as it's nearly straight. Perhaps the green arrow is not in exactly the right place, but, close enough.

If the green arrow pointed further to the outside, he'd rise up, the edge angles would diminish and the turn would straighten. That alone could reduce the centrifugal force (represented by the blue arrow) so that the balance vector continued to point into the base of support, and he'd continue skiing.

If it continued to point outside, he'd continue to rise and go right over.....he would not be in balance.

He'd have to re-orient the base of support so that the balance vector points into it again, or fall.
Reality check. Ever since that ninth grader told me that neither centrifugal or centripital forces exist and proceded to lecture me about Newtons law of motion and thermodynamic law I've searched to find a model that explains the physics of skiing without opening that can of worms. I jokingly refer to a concept that more than explains the interaction between, ski behavior, innertial mass, gravity and friction but no one likes it and the bunk meter twitches on the red peg. I diverge... In the picture Herman clearly has every intention of keeping as much weight as he possibly can on his inside ski. In the next instant his inside ski may become just as reversed cambered as the racer previous to him who's inside ski track is clearly visible and shows a pure carve. The dramatic inclination and extension of the outside leg in the fall line tells me he can't possibly be trying to exclusivly weight the outside ski, quite the opposite he is trying to keep the outside leg bones stacked as long as possible and as much weight on the inside ski as he can to keep the outside ski from being over pressured and washing out. Sorry if I don't agree but while the colored arrows are pretty, beyond that they deface and distract from an awesome display of skiing.
post #62 of 83
Quote:
Originally Posted by dogonjon View Post
In the picture Herman clearly has every intention of keeping as much weight as he possibly can on his inside ski.
Uhmmmmm.... oh really? Why on earth do you think he would want to put all this weight on the inside ski?

Quote:
The dramatic inclination and extension of the outside leg in the fall line tells me he can't possibly be trying to exclusivly weight the outside ski, quite the opposite he is trying to keep the outside leg bones stacked as long as possible and as much weight on the inside ski as he can to keep the outside ski from being over pressured and washing out. Sorry if I don't agree but while the colored arrows are pretty, beyond that they deface and distract from an awesome display of skiing.
Either you are joking around or very misguided. Sorry.
post #63 of 83
Quote:
Originally Posted by dogonjon View Post
In the picture Herman clearly has every intention of keeping as much weight as he possibly can on his inside ski. In the next instant his inside ski may become just as reversed cambered as the racer previous to him who's inside ski track is clearly visible and shows a pure carve. The dramatic inclination and extension of the outside leg in the fall line tells me he can't possibly be trying to exclusivly weight the outside ski, quite the opposite he is trying to keep the outside leg bones stacked as long as possible and as much weight on the inside ski as he can to keep the outside ski from being over pressured and washing out. Sorry if I don't agree but while the colored arrows are pretty, beyond that they deface and distract from an awesome display of skiing.
Do you even ski?

This should be entertaining...

:
post #64 of 83
Quote:
Originally Posted by dogonjon View Post
Reality check. Ever since that ninth grader told me that neither centrifugal or centripital forces exist and proceded to lecture me about Newtons law of motion and thermodynamic law I've searched to find a model that explains the physics of skiing without opening that can of worms.
Maybe this LINK will help.

Quote:
Originally Posted by dogonjon View Post
In the picture Herman clearly has every intention of keeping as much weight as he possibly can on his inside ski.
Now this is an interesting take on that picture. Would you mind posting a bit about your skiing experience, instructor training, and perhaps a video clip.
post #65 of 83
Quote:
Originally Posted by Max_501 View Post
Maybe this LINK will help.



Now this is an interesting take on that picture. Would you mind posting a bit about your skiing experience, instructor training, and perhaps a video clip.
Good one!
Centrifugal force: required for Newton's laws to work in a rotating frame of reference (Just one example of an accelerating frame of reference whrere F=ma would not work without it). Been there done that do a search.

Max asking for a video, who'da thunk it?
post #66 of 83
Quote:
Originally Posted by Ghost View Post
Max asking for a video, who'da thunk it?
The main reason I asked for it in this thread is because this statement is much different than I have been taught (both by HH and by racers). I figured seeing some vid of dogonjon carving would lend some insight into his opposite point of view.

Quote:
Originally Posted by dogonjon
In the picture Herman clearly has every intention of keeping as much weight as he possibly can on his inside ski.
In addition, I think all of the people that have been selected for the Ask a Pro forum should be willing to provide video. Looks like nearly half of them have vid up already. Lets see how the other half skis.

And this is another fun LINK on CForce.
post #67 of 83
Jongdog.....

I have to say it, since no one else has... your description of Hermann's skiing has defaced this picture more than the colorful arrows...

Just reading your post #61 has my bunk meter needle way past the redline... In fact, its way over in the Troll Zone!

If this is your true and honest understanding of contemporary skiing, you need to get out and ski with a few of my friends on the Mammoth Ski School. I have no doubt they can help straighten you out a bit...

Back to my cave, and watch the fireworks from this one....
:::::

(this will be a 5 bagger show!)
post #68 of 83
Pg 86 Harold Harb's Essentials of Skiing, figure 3-11 caption "To many observers, it might appear in frames 5-7 that I extend my outside leg to push my body to the inside of the arc. NOTHING COULD BE FURTHER FROM THE TRUTH! Flexing the stance leg at the end of the previous turn (the release, frames 2-3 ) enabled my momentum to send my body into the new arc. EXTENDING THE STANCE LEG IS MERELY TO MAINTAIN CONTACT. Continued flexing of the now-inside leg pulls my body further inside the arc."
In frame 7 of the photo sequence Harold is at the same point in the turn as Herman with similar alignment.

My work here is done, thank you for the can opener. Think the Think!
post #69 of 83
Quote:
Originally Posted by vail snopro View Post
Jongdog.....

If this is your true and honest understanding of contemporary skiing, you need to get out and ski with a few of my friends on the Mammoth Ski School. I have no doubt they can help straighten you out a bit...
Do you mean Klaus, Jan or Viktor? Or is it Mamood? Craig? Mark? Findley? We will have a laugh for you!
post #70 of 83
Quote:
Originally Posted by dogonjon View Post
In frame 7 of the photo sequence Harold is at the same point in the turn as Herman with similar alignment.

My work here is done, thank you for the can opener. Think the Think!
Do you have a point here? HH skies with very little weight on the inside ski.
post #71 of 83
Quote:
Originally Posted by dogonjon View Post
Pg 86 Harold Harb's Essentials of Skiing, figure 3-11 caption "To many observers, it might appear in frames 5-7 that I extend my outside leg to push my body to the inside of the arc. NOTHING COULD BE FURTHER FROM THE TRUTH! Flexing the stance leg at the end of the previous turn (the release, frames 2-3 ) enabled my momentum to send my body into the new arc. EXTENDING THE STANCE LEG IS MERELY TO MAINTAIN CONTACT. Continued flexing of the now-inside leg pulls my body further inside the arc."
In frame 7 of the photo sequence Harold is at the same point in the turn as Herman with similar alignment. !
Ok....so how does that equate to HM is trying to put as much weight as possible on the inside ski? ..I believe HH is talking about getting the necessary inclination to maintain balance from the centripedal force generated by the turn......I think that is where your understanding is perhaps falling apart, as earlier you seemed to indicate you don't believe these centripidal (or is it centrifugal, I always get the 2 confused...one is in, one is out), forces exist.

"Moving inside" does NOT necessarily equal placing more weight on the inside ski.


Quote:
Originally Posted by dogonjon View Post
My work here is done,
Acutally, I think you are just getting started.....:
post #72 of 83
Quote:
Originally Posted by dogonjon View Post
Pg 86 Harold Harb's Essentials of Skiing, figure 3-11 caption "To many observers, it might appear in frames 5-7 that I extend my outside leg to push my body to the inside of the arc. NOTHING COULD BE FURTHER FROM THE TRUTH! Flexing the stance leg at the end of the previous turn (the release, frames 2-3 ) enabled my momentum to send my body into the new arc. EXTENDING THE STANCE LEG IS MERELY TO MAINTAIN CONTACT. Continued flexing of the now-inside leg pulls my body further inside the arc."
In frame 7 of the photo sequence Harold is at the same point in the turn as Herman with similar alignment.

My work here is done, thank you for the can opener. Think the Think!
Dogonjon....uhmmm I don't recognize your name... I don't know if you are new or someone old with a new handle. But you are spewing absolute rubbish. First off, what on earth does that quote from HH's book have to do with the discussion at hand? If you knew anything about that quote, you would know that HH was referring to ILE during transition, which has absolutely nothing to do with the HM photo above.
post #73 of 83
Quote:
Originally Posted by borntoski683 View Post
Dogonjon....uhmmm I don't recognize your name... I don't know if you are new or someone old with a new handle. But you are spewing absolute rubbish. First off, what on earth does that quote from HH's book have to do with the discussion at hand? If you knew anything about that quote, you would know that HH was referring to ILE during transition, which has absolutely nothing to do with the HM photo above.

::: OMG!!!! I am acutally in agreement with Max501 and Borntoski in the same thread...! Does this mean we can finally ski in hell?

Everybody....and a 1, and a 2, and a 3..."Koom by ya....
post #74 of 83
It wasn't hard on this one SkiDude. now maybe someone can explain to me why his name is on the AskAPro list
post #75 of 83
Quote:
Originally Posted by CanuckInstructor View Post
..Think of the CSIA's 4 planes of balance:
Fore/Aft
Lateral
Vertical
Rotational
'Rotational' should explains HH introduce counteracting in his essentials.
But what would affect our Vertical balance? If out of balance what would happen?
Quote:
Originally Posted by BigE View Post
..Pivotting while locked has no positive effect as I cannot twist the skis. In fact, attempting to pivot and edge-locked ski could be highly injurious.
I think this is a very good hint to avoid injury.
Quote:
Originally Posted by BigE View Post
Look at descriptions of ILE, OLR, earlyweight shift for eg.... All these moves manipulate where this balance vector points. Transitions from one turn into another capitalize on the fact that the balance vector is no longer pointing into the base of support.
I think that's why HH said in his esential video the dangerous moment is right at the moment of changeover when both skis are flat. Is it because you have to bet on the ability of shaping up the new balance?
post #76 of 83
Quote:
Originally Posted by dogonjon View Post
Pg 86 Harold Harb's Essentials of Skiing, figure 3-11 caption "To many observers, it might appear in frames 5-7 that I extend my outside leg to push my body to the inside of the arc. NOTHING COULD BE FURTHER FROM THE TRUTH! Flexing the stance leg at the end of the previous turn (the release, frames 2-3 ) enabled my momentum to send my body into the new arc. EXTENDING THE STANCE LEG IS MERELY TO MAINTAIN CONTACT. Continued flexing of the now-inside leg pulls my body further inside the arc."
In frame 7 of the photo sequence Harold is at the same point in the turn as Herman with similar alignment.

My work here is done, thank you for the can opener. Think the Think!
What does the fact that HH teaches a turn that is not created from a push off move have to do with outside ski pressure and balance as it relates to BigE's well thought-out/presented post? If you are relating the two you are quite misguided. I could go into why Harald explained that movement the way he did, but that would be best kept to another thread, and would undoubtedly go way over your head anyway. As far as your work being done here... that isn't likely because you haven't said or done anything of value yet.

Later

GREG

BTW: SkiDude72; Although this isn't the first time we have agreed on a topic, you can add me to your list as well!
post #77 of 83
Wait a second. Someone new comes on the board and tries to introduce another point of view and you guys are so learning disabled you can't even consider it.

Let me put this another way. Your arsenal is so empty of inquiry tools and so loaded with advocacy armaments, I am afraid you are incapable of learning.

Please, remove the beans from your ears, and maybe, maybe, you might hear something interesting. Something that challenges your preconceived ideas. Something that makes you THINK. It might be that what's wrong about it is what you are adding to it. Ask and ye shall approach understanding. Close your mind and you will remain in the same state of ignorance you have enjoyed to this point.

I remember David MacPhail trying to impress upon you folks some ideas that were incomprehensible at the time. I believe ILE was born in his think tank, which we had to install away from here because the MOB was too busy slapping each other on the back for the clever insults hurled David's way.
post #78 of 83
Thread Starter 
OMG.

I can't imagine a world where blatant falsehoods should be considered as acceptable.

Dogonjon is suggesting that HM is about to do "the charleston" and that Ron Lemasters vectors obscure the photograph.

As "proof" he shows a deep misunderstanding of HH's entire treatise -- release by flexing THE OUTSIDE LEG. HOW IN HEAVEN WILL YOU DO THAT IF YOUR WEIGHT IS ON THE INSIDE LEG!

This has gotten beyond stupid. Even VSP has pointed this out! Hell has indeed frozen over, I'm agreeing with VSP.

nolo, OPEN YOUR EYES. Just because it is written down does not make it worthy of consideration.
post #79 of 83
If you succeed in driving him away, and who could blame him if he left, (pretty much what happened with DavidM) we'll never find out where he was going with this. Or don't you care to know?
post #80 of 83
Thread Starter 
This sure ain't DavidM or Greg Gurshman we're talking about here.

I see nothing in his posts other than an agenda to discredit those that disagree with the sacred PSIA scriptures and cover an otherwise decent thread with rubbish.

He's certainly successful on the second count.

Dynamic Counterbary indeed.
post #81 of 83
We should all be so lucky as to know every thing about every thing.
post #82 of 83
Thread Starter 
OK:

Quote:
Originally Posted by dogonjon View Post
??????? Let's talk about something real like Dynamic Counterbary.
post #83 of 83
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