Welcome, Guest. Please Login
SLINGING.ORG
 
Home Help Search Login


Page Index Toggle Pages: 1
Send Topic Print
I got to thinking: (Read 2526 times)
Funditor406
Descens
***
Offline


Shattered Remains. Wonder
why.

Posts: 224
Turah, Montana
Gender: male
I got to thinking:
Oct 16th, 2019 at 4:44pm
 
Now obviously a whip is very different. I wonder though if our science guys could use a similar approach to better understand sling mechanics?

https://youtu.be/AnaASTBn_K4
Back to top
 
 
IP Logged
 
NooneOfConsequence
Slinging.org Moderator
*****
Offline



Posts: 2983
Texas
Re: I got to thinking:
Reply #1 - Oct 16th, 2019 at 8:08pm
 
Yeah, I’ve watched that video about a dozen times so far, and it still fascinates me. I’m still waiting for the academic paper on this, but I don’t think it translates to slinging. That video is really focused on the transition of a knot on a whip as it breaks the sound barrier. In that respect the mechanics of a sling crack are identical but that’s has little to do with the actual slinging part.
Back to top
 

“My final hour is at hand. We face an enemy more numerous and cunning than the world has yet seen. Remember your training, and do not fear the hordes of Judas. I, without sin, shall cast the first stone. That will be your sign to attack! But you shall not fight this unholy enemy with stones. No! RAZOR GLANDES!  Aim for the eyes! May the Lord have mercy, for we shall show none!“  -Jesus the Noodler
 
IP Logged
 
NooneOfConsequence
Slinging.org Moderator
*****
Offline



Posts: 2983
Texas
Re: I got to thinking:
Reply #2 - Oct 16th, 2019 at 8:15pm
 
I do have some Mocap data from a few slinging motions, but I’m missing the speed of the ball, because it didn’t have a reflective marker.
Back to top
 

“My final hour is at hand. We face an enemy more numerous and cunning than the world has yet seen. Remember your training, and do not fear the hordes of Judas. I, without sin, shall cast the first stone. That will be your sign to attack! But you shall not fight this unholy enemy with stones. No! RAZOR GLANDES!  Aim for the eyes! May the Lord have mercy, for we shall show none!“  -Jesus the Noodler
 
IP Logged
 
Teg
Interfector Viris Spurii
*****
Offline



Posts: 1113
Central Europe
Gender: male
Re: I got to thinking:
Reply #3 - Oct 17th, 2019 at 5:35am
 
NooneOfConsequence wrote on Oct 16th, 2019 at 8:15pm:
I do have some Mocap data from a few slinging motions, but I’m missing the speed of the ball, because it didn’t have a reflective marker.


(With the danger of repeating your thoughts Roll Eyes )
There should be a synchronized, timestamped video recording available for this MOCAP?
Two options:
a) Requirement: video from several known positions.
rewrite the code to do pattern recognition of the video to do triangulation onto the ball.
appropriate color channel separation, edge detection and centroiding should give a decent result for marker position for each camera channel. Then feed it as an additional marker point to the triangulation routine of the software. But I'm not sure if you have that deep access to the software  Roll Eyes.

b) Requirement: video feed from single position with timestamp.
get the release time. approximate ball speed =  pouch speed at release time. This will yield an upper limit for the ball speed.
Back to top
 
 
IP Logged
 
Curious Aardvark
Forum Moderation
*****
Offline


Taller than the average
Dwarf

Posts: 13965
Midlands England
Gender: male
Re: I got to thinking:
Reply #4 - Oct 17th, 2019 at 6:28am
 
Cool byzantine capture Smiley

did you do any other styles ?
Back to top
 

Do All things with Honour and Generosity: Regret Nothing, Envy None, Apologise Seldom and Bow your head to No One  - works for me Smiley
 
IP Logged
 
vetryan15
Slinging.org Moderator
*****
Offline


Slinging Rocks!

Posts: 1913
Northern Maine
Gender: male
Re: I got to thinking:
Reply #5 - Oct 17th, 2019 at 6:55am
 
I am not technology inclined,  but what is Mocap? That is sweet. I vaguely remember seeing something liliklilike this before.
Back to top
 
WWW  
IP Logged
 
Teg
Interfector Viris Spurii
*****
Offline



Posts: 1113
Central Europe
Gender: male
Re: I got to thinking:
Reply #6 - Oct 17th, 2019 at 7:27am
 
vetryan15 wrote on Oct 17th, 2019 at 6:55am:
what is Mocap?


Motion capture. The tracking of movement in space. This allows to create a "digital image" of some real-world action in your computer and then do analysis and further processing on it (e.g. animations in films and computer games).

https://en.wikipedia.org/wiki/Motion_capture
Back to top
 
 
IP Logged
 
NooneOfConsequence
Slinging.org Moderator
*****
Offline



Posts: 2983
Texas
Re: I got to thinking:
Reply #7 - Oct 17th, 2019 at 7:50am
 
Curious Aardvark wrote on Oct 17th, 2019 at 6:28am:
Cool byzantine capture Smiley

did you do any other styles ?


If I could do it again today, I would have better form, but here are the other variations.
I was also confined to an enclosed lab and was only allowed to throw a very lightweight plastic ball.
Back to top
 

“My final hour is at hand. We face an enemy more numerous and cunning than the world has yet seen. Remember your training, and do not fear the hordes of Judas. I, without sin, shall cast the first stone. That will be your sign to attack! But you shall not fight this unholy enemy with stones. No! RAZOR GLANDES!  Aim for the eyes! May the Lord have mercy, for we shall show none!“  -Jesus the Noodler
 
IP Logged
 
NooneOfConsequence
Slinging.org Moderator
*****
Offline



Posts: 2983
Texas
Re: I got to thinking:
Reply #8 - Oct 21st, 2019 at 11:34am
 
Ok CP... I’ve been thinking about this, and I think I wanna was wrong when I said it doesn’t relate to slinging. The whip crack starts as a traveling wave, and heavier whip handles mean there is more momentum and thus it’s easier to get a good crack. There is a similar transfer of momentum from the ammo in the pouch to the pouch and release cord as the pouch is opening. I’ve noticed that heavy ammo tends to crack better... probably for the same reason that heavy whips crack easily.
Back to top
 

“My final hour is at hand. We face an enemy more numerous and cunning than the world has yet seen. Remember your training, and do not fear the hordes of Judas. I, without sin, shall cast the first stone. That will be your sign to attack! But you shall not fight this unholy enemy with stones. No! RAZOR GLANDES!  Aim for the eyes! May the Lord have mercy, for we shall show none!“  -Jesus the Noodler
 
IP Logged
 
Kick
Forum Moderation
*****
Offline



Posts: 4451
Finland
Re: I got to thinking:
Reply #9 - Oct 21st, 2019 at 12:21pm
 
NooneOfConsequence wrote on Oct 21st, 2019 at 11:34am:
Ok CP... I’ve been thinking about this, and I think I wanna was wrong when I said it doesn’t relate to slinging. The whip crack starts as a traveling wave, and heavier whip handles mean there is more momentum and thus it’s easier to get a good crack. There is a similar transfer of momentum from the ammo in the pouch to the pouch and release cord as the pouch is opening. I’ve noticed that heavy ammo tends to crack better... probably for the same reason that heavy whips crack easily.


I've found this too. It still depends a lot on the whip but the extra momentum the larger ammo brings helps with cracking. Whether that really means a faster release/positive effect of the "performance" of the sling, I'm not sure. Cracking a whip and slinging are related but I'm not sure how closely.
Back to top
 

You are a great guy Kick but also slightly scary at times. - Morphy
"Nothing matters, but it’s perhaps more comfortable to keep calm and not interfere with other people." - H.P. Lovecraft, in a letter to Frank Belknap Long, 7 October, 1923
 
IP Logged
 
Funditor406
Descens
***
Offline


Shattered Remains. Wonder
why.

Posts: 224
Turah, Montana
Gender: male
Re: I got to thinking:
Reply #10 - Oct 22nd, 2019 at 5:12pm
 
I figured, I thought it was something like that, but I just didn’t have the scientific vocabulary or the know-how to express it.
Back to top
 
 
IP Logged
 
Page Index Toggle Pages: 1
Send Topic Print
(Moderators: Morphy, vetryan15, Chris, Curious Aardvark, Kick, Rat Man, joe_meadmaker)